Anesthesiologist's Manual of Surgical Procedures, 4th ed.

Appendices

P.A-2

Appendix A: Preoperative Considerations

Preoperative Laboratory Testing and Diagnostic Studies

Stephen P. Fischer

The value and utility of preop diagnostic studies have become central issues in evaluating cost-effective health care in the surgical patient. It is estimated that up to $3 billion is spent in the United States annually on preop laboratory and diagnostic studies. Unnecessary testing is inefficient and expensive, and it requires additional technical resources. Inappropriate studies may lead to evaluation of ‘borderline’ or false-positive laboratory abnormalities. This may result in unnecessary OR delays, cancellations, and potential patient risk through additional testing and follow-up.

Surgical patients require preop lab and diagnostic studies that are consistent with their medical histories, the proposed operative procedures, and the potential for blood loss. Preop lab and diagnostic testing should be ordered for specific clinical indications rather than simply because the patient is about to undergo a certain surgical procedure.

The following preop diagnostic guidelines provide basic recommendations. They are not intended as absolute or standard requirements. Practice guidelines should be modified based on clinical needs and individual practice, to ensure the highest quality of anesthesia and surgical patient care.

Summary of Preop Studies

Chest x-ray (CXR)

Overview: A preop CXR should be used to assess the presence of acute, progressive, or chronic changes in cardiac/pulmonary disease. The decision to obtain a preop CXR should be individualized and based on clinical indications (seeTable A-1). CXRs should not be part of a routine preop screening protocol.
Clinical indications: Pneumonia; pulmonary edema; atelectasis; aortic aneurysm; mediastinal or pulmonary masses; tracheal deviation; pulmonary HTN; cardiomegaly; advanced COPD and blebs; dextrocardia; pulmonary embolism.

Electrocardiogram (ECG)

Overview: ECGs evaluate cardiac rhythm/conduction disturbances, ischemia, myocardial infarction, hypertrophy, and metabolic and electrolyte disorders.
Clinical indications: Patients with suspected or known Hx of CAD; patient age > 50; HTN; hx of dysrhythmias, chest pain; CHF; diabetes; OSA, cerebral vascular disease and PVD; syncope or presyncope; dizziness; SOB; DOE; PND; palpitations; leg/ankle edema; abnormal valvular murmurs.

Liver function test (LFT)

Overview: LFTs establish the absence or presence of hepatic injury and the degree of hepatic reserve in disease states. LFTs consist of: AST(SGOT), ALT(SGPT), GGTP, alkaline phosphatase, serum albumin, and bilirubin.
Clinical indications: Patients with suspected or known Hx of hepatitis (viral, alcohol, drugs); infiltration (tumor, immunologic); cirrhosis; portal HTN; gallbladder or biliary tract disease; jaundice; intravascular hemolysis.

Renal function testing

Overview: Renal function testing measures glomerular filtration and the magnitude of renal tubular dysfunction. These tests include: serum creatinine and BUN.
Clinical indications: Renal function testing is indicated for patients with HTN; increased fluid overload (CHF/peripheral edema/ascites) associated with cardiac, hepatic, or renal impairment; dehydration; diabetes; nausea, emesis, or anorexia; polyuria; nocturia; oliguria; anuria; high-risk surgery in patients with low CO syndrome; hematuria; costovertebral angle pain: renal transplant Hx; renal disease; dialysis.

Hemoglobin (Hb), Hematocrit (Hct), CBC

Overview: The decision to obtain a preop Hgb, Hct, or CBC should be individualized and based on clinical indications, medical Hx, and the proposed surgical procedure. Hgb/Hct or CBC should not be part of a routine preop screening protocol.
Clinical indications: Hematological disorder; bleeding/coagulopathy Hx; malignancy; chemotherapy; radiation therapy (CBC); renal disease; anticoagulant and steroid therapy; surgical procedures with high blood loss (> 1500 mL); highly invasive or trauma surgery; malabsorption/poor nutrition status; CNS disease.

Pregnancy testing

Overview: The decision to obtain a preop pregnancy test should be based on clinical Hx and examination. Several assays are available (serum hCG, urine hCG); β-hCG detectable in maternal urine and blood 8–9 d postconception.
Clinical indications: Sexually active; time of last menstrual period; presence or absence of birth control method; patient intuition

Coagulation testing

Overview: Coagulation testing, or clotting function studies, should be obtained in patients with known or suspected coagulopathies as indicated from H&P and drug therapies. Tests include: prothrombin time (PT), partial prothrombin time (PTT). INR, platelet (Plt) count.
Clinical indications: Bleeding disorder Hx; anticoagulants or other drugs affecting coagulation; critical-risk surgeries with significant blood loss expected; hepatic disease: malabsorption/poor nutrition

Urine analysis

Overview: Assessment of renal function, infection, intravascular volume status, metabolic disorders
Clinical indications: There are no routine anesthesia preop requirements for a urine analysis.

P.A-3

Table A-1. Diagnosis-Based Preop Testing

Preop Diagnosis

ECG

CXR

Hct/Hb

CBC

Lytes

Renal

Glucose

Coag

LFTs

Drug levels

Ca+

Cardiac disease:

 

 

 

 

 

 

 

 

 

 

 

Chronic atrial fib

X

 

 

 

 

 

 

 

 

X2

 

CHF

X

±

 

 

 

±

 

 

 

 

 

HTN

X

±

 

 

X1

X

 

 

 

 

 

MI history

X

 

 

 

±

 

 

 

 

 

 

PVD

X

 

 

 

 

 

 

 

 

 

 

Stable angina

X

 

 

 

±

 

 

 

 

 

 

Valvular heart disease

X

±

 

 

 

 

 

 

 

 

 

CNS disorders:

 

 

 

 

 

 

 

 

 

 

 

Seizures

X

 

 

X

X

 

X

 

 

X

 

Stroke

X

 

 

X

X

 

X

 

 

X

 

Tumor

X

 

 

X

 

 

 

 

 

 

 

Vascular/aneurysms

X

 

X

 

 

 

 

 

 

 

 

Coagulopathies

 

 

 

X

 

 

 

X

 

 

 

Endocrine disease:

 

 

 

 

 

 

 

 

 

 

 

Addison's disease

 

 

 

X

X

 

X

 

 

 

 

Cushing's disease

 

 

 

X

X

 

X

 

 

 

 

Diabetes

X

 

 

 

±

X

X

 

 

 

 

Hyperparathyroidism

X

 

X

 

X

 

 

 

 

 

X

Hyperthyroidism

X

 

X

 

X

 

 

 

 

 

X

Hypoparathyroidism

X

 

 

 

X

 

 

 

 

 

X

Hypothyroidism

X

 

X

 

X

 

 

 

 

 

 

Hematological disorders

 

 

 

X

 

 

 

 

 

 

 

Hepatic disease:

 

 

 

 

 

 

 

 

 

 

 

Alcohol/drug-induced

 

 

 

 

 

 

 

X

X

 

 

Infectious hepatitis

 

 

 

 

 

 

 

X

X

 

 

Tumor infiltration

 

 

 

 

 

 

 

X

X

 

 

Malabsorption/poor nutrition

X

 

 

X

X

X

X

±

 

 

 

Malignancy

 

 

 

X

 

 

 

 

 

 

 

Morbid obesity

X

±

 

 

 

 

X

 

 

 

 

Pulmonary disease:

 

 

 

 

 

 

 

 

 

 

 

Asthma

(PFT only if symptomatic; otherwise no tests required)

Chronic bronchitis

X

±

 

X

 

 

 

 

 

 

 

Emphysema

X

±

 

 

 

 

 

 

 

X3

 

Renal disease

 

 

X

 

X

X

 

 

 

 

 

Select drug therapies:

 

 

 

 

 

 

 

 

 

 

 

Anticoagulants

 

 

X

 

 

 

 

X

 

 

 

Aspirin/NSAID

no tests

Chemotherapy

 

 

 

X

 

 

 

 

 

 

 

Digoxin (digitalis)

X

 

 

 

±

 

 

 

 

X

 

Dilantin

 

 

 

 

 

 

 

 

 

X

 

Diuretics

 

 

 

 

X

X

 

 

 

 

 

Phenobarbital

 

 

 

 

 

 

 

 

 

X

 

Steroids

 

 

 

X

 

 

X

 

 

 

 

Theophylline

 

 

 

 

 

 

 

 

 

X

 

X = OBTAIN ± = CONSIDER
1 Patients on diuretics
2 Patients on digoxin
3 Patients on theophylline

P.A-4

Suggested Readings

  1. Roizen MF, Cohn S: Preoperative evaluation for elective surgery—what laboratory tests are needed? In Advances in Anesthesia, Vol 10. Stoelting RK, ed. Mosby-Year Book, St. Louis: 1993, 25–47.
  2. Schiff RL, Emanuele MA: The surgical patient with diabetes mellitus: guidelines for management. J Gen Intern Med1995; 10(3):154–61.
  3. Bapoje SR, Whitaker JF, Schulz T, et al: Preoperative evaluation of the patient with pulmonary disease. Chest2007; 132(5):1637–45.
  4. Cohn SL, Auerbach AD: Preoperative cardiac risk stratification 2007: evolving evidence, evolving strategies. J Hosp Med2007; 2(3):174–80.

Perioperative Beta-Blocker Therapy

Cliff Schmiesing

There are new developments in the area of Perioperative Beta-Blocker (PBB) therapy, tempering the initial enthusiasm for the practice. Several recent clinical trials, retrospective reviews, and meta-analyses have not demonstrated the clinical benefit of the initial studies published nearly a decade ago, and have even demonstrated harm. The PBB issue has also taken on increased prominence and importance as it is frequently used as a measure of health care quality and benchmarking by various national organizations. Many research questions and practical considerations still remain unanswered. Identifying an individual patient likely to benefit for PBB can be difficult, especially when the risks appear intermediate or low. Choosing which β blocker, and the time frame to initiate treatment and how long to continue it remain unclear; as is the mechanism(s) underlying the therapeutic benefit of PBB. Lastly, development and evaluation of optimal care-delivery mechanisms for implementing PBB therapy are lacking.

Despite these limitations, the clinical evidence continues to favor the benefit of PBB in selected patient groups. The American Heart Association/American College of Cardiology (AHA/ACC) recently released updated recommendations for PBB in their 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery. The guidelines continue to recommend PBB across a wide spectrum of patients. Recommendations are divided into Class I, and Class IIa and IIb according to the strength of the supporting evidence, derived from randomized and nonrandomized clinical trials, case studies, expert opinion and the standard-of-care. A Class I recommendation is given for conditions where there is evidence and/or general agreement that PBB is beneficial, useful, and effective. Class IIa conditions are those where there is conflicting evidence and/or divergence of opinion about efficacy of PBB, but the weight of evidence favors it. A Class IIb recommendation is given when efficacy is less well established. Recommendations are stratified according to surgery type: vascular, high or intermediate risk (nonvascular), and low risk surgery, and also by the likelihood and severity of coronary heart disease (CHD). CHD is classified as low, intermediate, and high risk as determined by test results, and the presence of clinical risk factors including: known CHD, compensated or prior heart failure, diabetes mellitus, renal insufficiency, and cerebrovascular disease.

The AHA/ACC report gives a Class I recommendation for two conditions: (1) PBB should be continued in patients undergoing surgery who are already receiving β blockers to treat cardiovascular disease; and (2) β blockers should be given to patients undergoing vascular surgery who also have evidence of ischemia on preoperative testing. Class IIa (PBB probablyrecommended) indications include: (1) vascular surgery patients where preop assessment identifies

P.A-5

CAD; (2) vascular surgery patients with multiple risk factors for CAD; and (3) patients undergoing intermediate- and high-risk surgical procedures who also have CAD or who have multiple risk factors for it. The Class IIb (consider PBB) recommendation is given for two groups: (1) patients undergoing intermediate or high-risk surgery, including vascular surgery, who also have a single risk factor; and (2) patients undergoing vascular surgery at low cardiac risk. The AHA/ACC recommendations are summarized in Table A-2. These recommendations have not been updated since the publication of the POISE trial in 2008, which cast doubt on the benefit of PBB and showed an increased risk of death and stroke related to hypotension that effectively cancelled out the cardiovascular benefits of PBB, but of note, it excluded patients already taking β blocker medications. It is possible future recommendations will change, especially for lower risk patients in light of the POISE trial results. PBB therapy, when utilized, should be probably be started at least several days before surgery and titrated to heart rate decreasing effect—‘Start low and go slow’. This is not always possible or practical.

Table A-2. Recommendations for Perioperative Beta-Blocker Therapy (Adapted from the AHA/ACC Recommendations for Perioperative Beta-Blocker Therapy Based on Published Randomized Clinical Trials (1))

Surgery Type

No Risk Factors

≥1 Risk Factor

CHD or High Cardiac Risk (≥3 Risk Factors)

Taking b-blocker

Vascular

Consider β-blocker

Probably give β-blocker

+ Cardiac ischemia on preop testing→give β-blocker
No ischemia or no prior test→probably give β-blocker

Continue β-blocker

Intermediate Risk

Inadequate data

Consider β-blocker

Probably give β-blocker

Continue β-blocker

Low Risk

Inadequate data

Inadequate data

Inadequate data

Continue β-blocker

In summary, PBB therapy is not beneficial for all patients, even for most patients. β blockers should be continued perioperatively for those patients taking one (unless new contraindications develop) and should be considered in the select group of vascular surgery patients with cardiac ischemia on stress testing, unless contraindicated. The need to consider a patient's risk profile and in some cases to start and manage PBB therapy underscores the importance of a timely and thorough preoperative assessment by the anesthesiologist or other physician with an understanding of this important perioperative intervention.

Suggested Readings

  1. Fleisher Lee A., et al: ACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery) Circulation; 116(17):1971–1996.
  2. POISE Study Group. Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomized controlled trial. Lancet2008; 371:1839–47.
  3. Fleisher, Lee A., et al: ACC/AHA 2006 Guideline Update on Perioperative Cardiovascular Evaluation for Noncardiac Surgery: Focused Update on Perioperative Beta-Blocker Therapy – A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2002 Guidelines on Perioperative Cardiovascular Evaluation for Noncardiac Surgery). Anesth Analg2007; 104:15–26.
  4. Lindenauer PK, Pekow P, Wang K, et al. Perioperative ß-blocker therapy and mortality after major noncardiac surgery. N Engl J Med2005; 353:349-61.
  5. Fleisher, Lee A., Perioperative ß-Blockade: How Best to Translate Evidence into Practice. Anesth Analg2007; 104:1–3.

P.A-6

P.B-1

Appendix B: Standard Adult Anesthetic Protocols

Richard A. Jaffe

  1. Philip Larson Jr.

Cliff Schmiesing

Steve Shafer

Standard Monitors (Noninvasive)

Blood pressure (BP)

Usually noninvasive (oscillometric) technique. Match cuff width to arm size to avoid inaccurate BP.

Capnometry/capnography

Measurement of ETCO2/display of wave form

Gas analyzer (e.g., IR, mass spectometry)

Measurement of respired gases and anesthetics

Electrocardiogram (ECG)

5-lead preferred. Usual display: lead II and V4 or 5

Esophageal or precordial stethoscope

Breath and heart sounds monitored; dysrhythmias and DBP may be detected. Seldom used today, because sound competes with more useful pulse oximetry sound

Nerve stimulator

Monitor status of neuromuscular blockade

Oxygen analyzer

Measurement of FiO2

Pulse oximetry

Measurement of O2 saturation of hemoglobin; also gives a pulse sound that indicates heart rate, rhythm, and change in saturation

Temperature

Nasal, esophageal, bladder, rectal, tympanic, or skin

Visual observation of patient

Skin color, pupils, temperature, edema, sweating, movement

Ventilator function monitors

PIP, TV, disconnect alarm, pressure-volume/flow-volume loops, etc.

Standard Anesthetic Management (Adult ASA 1 & 2)

*NB: The following sections are guidelines only (for an otherwise healthy 70 kg adult). Specific drugs and drug dosages should be individualized, based on the physiological and pharmacological status of the patient, including factors such as age, weight, concurrent medication, and comorbidities.

Premedication

Light

 

Midazolam 1–2 mg iv
Lorazepam 1–2 mg
Hydroxyzine 25–100 mg

po 1 h preop
po 1 h preop

Moderate

 

Midazolam 2–3 mg iv
± Fentanyl 25–100 mcg iv

Prior to induction (in patient holding area or OR)
Monitor for respiratory depression or apnea.

Heavy

 

Diazepam 10 mg
+ Morphine 0.1 mg/kg
with Scopolamine 0.2–0.4 mg

po 1–2 h preop
im 30–60 min preop

P.B-2

Induction Techniques

Preinduction

 

1.     [check mark] anesthesia machine, suction, airway equipment, drugs.

2.     Attach monitors and verify function.

3.     Administer 100% O2 by mask × 1–3 min.

4.     Administer supplemental sedation/analgesia (as appropriate).

 

 

e.g.: fentanyl
± midazolam

1–3 mcg/kg iv
0.03–0.1 mg/kg iv

Induction agents

 

Propofol

1.5–2.5 mg/kg iv (in increments) NB: Pain on injection may be lessened by prior administration of lidocaine 1% 5–10 mL.

 

Thiopental

3–5 mg/kg iv

 

Etomidate

0.2–0.4 mg/kg iv NB: Pain on injection; myoclonus

Muscle relaxants for intubation

 

Drugs

Doses

Onset

Duration

Vecuronium

Rocuronium
Pancuronium
Mivacurium
Cisatracurium
Succinylcholine:
   If given after defasciculating dose of NMR
Infusion

0.1 mg/kg
0.2 mg/kg (rapid onset)
0.6–1.2 mg/kg
0.1 mg/kg
0.1–0.2 mg/kg
0.2 mg/kg
1.0 mg/kg
1.5 mg/kg


1 g/250–500 NS (titrated to effect)

2–3 min
< 2 min
45–90 sec
3–4 min
1–2 min
2 min
30–60 sec
30–60 sec


+60 sec

24–30 min
45–90 min
30–120 min
40–65 min
6–10 min
40–80 min
4–8 min
4–8 min


While infusing (phase II block possible)

Maintenance Techniques

Inhalational anesthesia

 

30–100% O2
+ 0–70% N2O
+ Isoflurane (MAC in 100% O2 = 1.17%) or Sevoflurane (MAC = 1.8%) titrated to effect
Alternatively for short procedures, consider desflurane (MAC = 6.6%)

Balanced anesthesia

 

30–100% O2
+ 0–70% N2O
+ Meperidine 0.5–1.5 mg/kg/3–4 h (intermittent bolus)
or morphine 0.05–0.15 mg/kg/3–4 h (intermittent bolus)
or fentanyl 1–10 mcg/kg prn response to surgical stimulation
or remifentanil 0.05–2 mcg/kg/min prn response to surgical stimulation (no residual analgesia)
+ Isoflurane or sevoflurane titrated to effect
or propofol 50–200 mcg/kg/min (titrated to effect)
Alternatively, for short procedures consider desflurane (MAC = 6.6%).

Total intravenous anesthesia (TIVA)1

 

Oxygen 30% in N2O (continue 70% N2O until end of procedure)

+ Remifentanil infusion*
(infusion off 2–5 min before end of surgery)
+ Propofol bolus + infusion
(infusion off 2–5 min before end of surgery)

Induction infusion
Maintenance infusion
Induction bolus
Maintenance infusion

@ 0.5–1 mcg/kg/min × 1–2 min
@ 0.05–0.2 mcg/kg/min
1–1.5 mg/kg
@ 40–80 mcg/kg/min

   

 

Oxygen 100%; Can add air 50%, but it seldom offers any advantage

+ Remifentanil infusion*

Induction infusion

@ 0.5–1 mcg/kg/min × 1–2 min

   

 

(infusion off 5 min before end of surgery)

Maintenance 10 min before end surgery

@ 0.1–0.35 mcg/kg/min
@ 0.05–0.1 mcg/kg/min

   

 

+ Propofol bolus + infusion

Induction bolus

1–1.5 mg/kg

   

 

(infusion off 2–3 min before end of surgery)

Maintenance 10 min before end surgery

@ 60–90 mcg/kg/min
@ 20–40 mcg/kg/min

   

 

 

*No residual analgesia: postop pain management depends on type of surgery, and analgesic requirements may be substantial. Recommend having fentanyl or meperidine for quick pain relief followed by morphine or dihydromorphone for prolonged pain relief.
1Steven Shafer, MD
Source:

P.B-3

If continued muscle relaxation is required during the above maintenance techniques, several options are available. Always use a nerve stimulator to assess block before re-dosing.

Short-acting

 

Mivacurium

0.1 mg/kg/10–20 min or 1–15 mcg/kg/min

Intermediate

 

Vecuronium
Rocuronium
Cisatracurium

0.025 mg/kg/30 min
0.6 mg/kg/30 min
0.2 mg/kg/40 min

Long-acting

 

Pancuronium

0.02 mg/kg/60–90 min

Emergence

1. Reversal of muscle relaxant

 

As surgical conditions permit, reverse residual muscle relaxant (when at least 1 twitch is present in train-of-four) with one of the following:
   Neostigmine 0.05–0.07 (maximum dose) mg/kg iv + glycopyrrolate 0.01 mg/kg iv, or Edrophonium 0.5–1.0 (maximum dose) mg/kg iv + atropine 0.015 mg/kg iv.

2. Analgesia

 

If remifentanil was used during surgery, supplemental analgesics will be necessary and should be given promptly after emergence.

3. Nausea prophylaxis

 

Ondansetron (4 mg iv) (or dolasetron (12.5 mg iv), or granisetron (100 mcg iv). Also, consider adding dexamethasone 4–8 mg and/or metoclopramide (10–20 mg iv). The use of droperidol (0.625 mg iv) is unfortunately controversial because of effects on cardiac conduction at higher doses. Consider OG tube placement and suction to empty stomach. See Prevention of PONV (below).

4. O2

 

D/C N2O/volatile agents and administer 100% O2.

5. Suction

 

Suction oropharynx thoroughly.

6. Extubation

 

Extubate after protective airway reflexes have returned, the patient is breathing spontaneously, and is able to follow commands.

Monitored Anesthesia Care (MAC)

  1. Standard monitoring with regular verbal contact.
  2. Nasal O2(qualitative measurement of respiratory rate, volume of ventilation, and ETCO2 can be obtained by attaching a sampling catheter to the nasal cannula.)

P.B-4

  1. Light-to-moderate levels of sedation (± analgesia) can be maintained using a propofol infusion (25–100 mcg/kg/min), or with intermittent bolus injections of midazolam (0.25–1 mg) ± fentanyl (10–25 mcg) or with a remifentanil infusion (0.025–0.07 mcg/kg/min), titrated to effect. Monitor closely for respiratory depression.
  2. Alternatively, dexmedetomidine (an α–2 agonist) can produce excellent sedation and analgesia without respiratory depression. The loading dose is typically 1 mcg/kg iv over ~ 15 min (↓ BP may occur) followed by an infusion of 0.2–0.7 mcg/kg/h.
  3. If the initial local anesthetic injection will be painful (e.g., retrobulbar block), then a brief period of analgesia, sedation, and amnesia can be induced with:

 

 

Advantages:

Disadvantages:

A.

Midazolam (0.5–2 mg) ± Ketamine (10–20 mg) ± alfentanil 3–7 mcg/kg
or

Profound amnesia and analgesia.
Usually no apnea and airway reflexes maintained.

Patient not “asleep.”
Timing is important.
Possible ↑BP and HR

 

remifentanil 0.5 mcg/kg all injected 2–3 min before pain:
or

Patient usually able to cooperate.

 

B.

STP (1–2 mg/kg) or propofol (0.5–1 mg/kg)

Patient “asleep” ± fentanyl (25–50 mcg/kg)

Possible apnea with loss of airway
↓ BP
Patient unresponsive.

Rapid-Sequence Induction of Anesthesia (Full-Stomach Precautions)1

1. gastric volume/acidity

 

Ranitidine 50 mg iv at least 30–60 min before induction
Metoclopramide 10 mg iv 30–60 min before induction
0.3 M sodium citrate 30 mL po immediately before induction

2. Induction

 

Preoxygenation = 3 min. Suction must be readily available. Stylet ETT.
± Defasciculate: e.g., vecuronium 1 mg iv 3–5 min before using succinylcholine.
Cricoid pressure (Sellick maneuver) by assistant (8–10 lb pressure; beware of force transfer to C6 vertebra). Effective cricoid pressure makes laryngoscopy, mask ventilation, and LMA insertion difficult. Consider Trendelenburg position with graded release of cricoid pressure during laryngoscopy.
Choice of induction agent depends on patient condition including hemodynamic stability. Options include:
Etomidate 0.1–0.4 mg/kg
Or

Ketamine 1 mg/kg
or for patients better able to tolerate ↓ BP:
STP 2–5 mg/kg
Or
Propofol 1–2.5 mg/kg
+ Succinylcholine 1.5 mg/kg or rocuronium 1.2 mg/kg (slightly slower onset) for intubation
Lungs may be ventilated while waiting for NMB—avoid airway pressure > 20 cm H2O

3. Intubation

 

Intubate only when the patient is fully relaxed.
Watch chest movement and auscultate for equal BBS.
[check mark] expired CO2 on monitor.
Listen over stomach.
Secure ETT and release cricoid pressure.
Pass NG/OG tube and suction stomach contents.

4. Failed intubation protocol

 

[See Anesthetic Considerations for Cesarean Section, Obstetric Surgery, 823.]

5. Maintenance

 

As indicated by patient's condition and type of surgery.

6. Extubation

 

Repeat NG/OG suction is often useful before emergence and extubation. Extubate when patient is awake and has active laryngeal protective reflexes. Remember, some may require postop ICU care until safe extubation can be assured.

P.B-5

Special Pediatric Considerations

  1. The same principles apply in children requiring surgery, and in those who may have full stomachs. Consider emptying the stomach with an OG tube prior to induction in patients with pyloric stenosis or with high-grade intestinal obstruction following po barium. If iv is placed, continue as indicated previously. If iv access is difficult, O2/sevoflurane induction with cricoid pressure, succinylcholine (2–4 mg/kg im) will permit intubation and minimize risks of gastric aspiration.
  2. Awake intubation in neonates and sick infants may be the safest method.

Fiberoptic Intubation Protocol; Awake and Asleep2–4

  1. Philip Larson Jr.

Premedication

 

If not contraindicated, patients should receive mild-to-moderate sedation with meperidine 0.5 mg/kg or fentanyl 0.3–0.5 mcg/kg and midazolam 2–4 mg iv.

Topical anesthesia

 

When premedication has been established, for awake FOI the oropharynx is sprayed vigorously ~ 6 times over a span of 10 min with lidocaine 4% solution using a disposable EZ spray unit powered with oxygen. Initially, the spray is directed at the front of the tongue; gradually, it is directed further back in the throat, until the entire oropharynx is numb. Having the patient inhale deeply while spraying enhances the topical effect. In reality, the lateral recesses of the oropharynx need not be anesthetized topically because both fiberoptic laryngoscope (FOL) and ETT are confined to the midline of the mouth.

Tracheal anesthesia

 

With patient breathing oxygen from anesthesia circuit or transport mask, transtracheal injection of cocaine or lidocaine 4% (4 mL) is made through the cricothyroid membrane, using a 5-mL syringe and a 23-ga, 3/4-inch needle. So that this injection can be made as rapidly as possible, it is important to use a small syringe, making certain that the connection between syringe and needle is tight. It is important that the operator's hand be fixed firmly against the patient's upper chest to assure that needle movement is minimized should the patient start to cough, and that the full injection is made into the trachea. When the injection is complete, the patient is urged to cough vigorously.

Laryngoscopy

 

After the mouth and trachea are anesthetized with local anesthetic, an oral airway with a central orifice (e.g., Tudor-Williams, Patel, Ovassapian airway) is placed in the midline of the mouth. A 7-mm orotracheal tube, without connector attached, is placed over a FOL. With the operator at the patient's side near the waist, the FOL is introduced through the hole in the airway and advanced to end of airway. At this point, the epiglottis should be visible. The tip of the fiber optic scope is flexed toward the operator about 15–20°, which should bring arytenoid cartilages and laryngeal opening into view. The scope is advanced into the larynx so that tracheal rings can be visualized. Often, the carina also can be visualized. The laryngoscopist also can place the scope in the airway by darkening the room and using the scope as a light wand, directing the light externally to the sternal notch and advancing it down the trachea. If a wire-reinforced tube is desired, use a Patel or Ovassapian airway instead of the Tudor-Williams airway for guidance, because these airways can be removed with the tube connector in place.

Intubation

 

The scope is placed on the patient's chest and, holding it so that it not advanced further, the orotracheal tube is advanced gently into the trachea. To facilitate passage of the orotracheal tube past the arytenoid cartilages and into the larynx, it is necessary to rotate the tube counterclockwise 90°—or even as much as 180°—several times as it is being advanced.
Using this rotational movement, the operator should never need to push hard on the tube to position it in the larynx. After the tube is in place, the FOL and oral airway are removed, and the 15-mm connector is reattached to the tube. ETCO2 confirms proper placement. The orotracheal tube is then firmly taped in place at one side of the mouth.
If manual ventilation of the lungs is possible, it is often beneficial for both patient and anesthesiologist to perform FOI with the patient anesthetized. This is particularly true for patients with cervical spine injuries where manipulation of the head during direct laryngoscopy or coughing during topicalization of the airway or insertion of the tube during awake FOI may aggravate the spinal cord injury. Asleep FOI involves inducing GA, inserting an LMA, and placing the patient on controlled ventilation. Then proceed with Plan C (see ref 4). In brief, a 6.0 uncuffed tube is mounted on the FOI, the FOI is inserted into the trachea using the LMA as a guide, and the 6.0 tube is lubricated and inserted into the laryngeal opening. The FOI is removed and the lungs ventilated via the 6.0 tube. A medium sized airway exchange catheter (AEC) is lubricated on one end and inserted into the trachea via the 6.0 tube. The AEC usually meets resistance at the distal end of the 6.0 tube. If this occurs, rotate the 6.0 tube while pushing on the AEC. Once the AEC is a few cm beyond the tip of the 6.0 tube, the tube and LMA are removed en-block leaving the AEC in the airway. With the AEC in the far right corner of the mouth, thread the final endotracheal tube on the AEC and gently advance it through the mouth into the larynx, rotating it counterclockwise to avoid obstruction from the right arytenoid cartilage. Then remove the AEC and connect the ETT to the anesthetic circuit.

P.B-6

Suggested Readings

  1. Larson CP, Steadman RH: Management of the full stomach: a reevaluation. Curr Rev Clin Anesth2005; 25:253–64.
  2. Larson CP: Fiberoptic intubation of the trachea, Part I. Curr Rev Clin Anesth2000; 21:117–28.
  3. Larson CP: Fiberoptic intubation of the trachea, Part II. Curr Rev Clin Anesth2001; 21:129–36.
  4. Larson CP: A safe, effective, reliable modification of the ASA difficult airway algorithm for adult patients. Curr Rev Clin Anesth2002; 23:1–12.
  5. Weiss M, Gerber AC: Rapid sequence induction in children—it's not a matter of time! PediatricAnesth 2008; 18(2):97–9.

Prevention of Ponv (Adapted from Gan, et al, 2007.)

Clifford Schmiesing

PONV risk factors

Patient-related

Female gender
Nonsmoking status
H/o PONV/motion sickness

Simple Risk Score for PONV in Adults: assign 1 point for each of the following risk factors: female gender, nonsmoker, hx of PONV, postop opioids. Risk of PONV: point sum 0 = 10%; 1 = 20%; 2 = 40%; 3 =6 0%, and 4 = 80%.

Anesthetic-related

Volatile anesthetics
Nitrous oxide
Intra/postop opioids
High dose neostigmine

Surgical-related

Duration of surgery
Type of surgery

Each 30 min → in duration → PONV risk by 60%
Laparoscopy, laparotomy, breast, strabismus, plastic, maxillofacial, gynecologic, abdominal, neurologic, ophthalmologic, urologic

Antiemetics

Pharmacologic Agents

Timing of administration

 

Serotonin blockers

End of surgery

Ondansetron 4 mg iv, Granisetron 0.35–1.5 mg iv, Dolasetron 12.5 mg iv

Dexamethasone 4–8 mg iv

At induction

Adverse effects not seen with single bolus dose.

Droperidol 0.625–1.25 mg iv

30 min before end of surgery

Consider risk of Q-T prolongation and cardiac dysrhythmias especially at higher doses. Risk low at dose range of 0.625–1.25 mg iv.

Promethazine 6.25–25 mg iv

30 min before end of surgery

Sedating and may cause local tissue damage if iv catheter infiltration occurs.

Metoclopramide 10–20 mg iv

30 min before end of surgery

Can cause anxiety, confusion, or visual changes.

Prochlorperazine 5–10 mg iv

30 min before end of surgery

Scopolamine transdermal patch

2–4 h before surgery

May cause sedation, dry mouth, visual changes, and confusion, especially in the elderly

Ephedrine 0.5 mg/kg IM

End of surgery or as rescue rx in PACU

Nonpharmacologic

Acupuncture, acupressure

Before or after surgery

 

PONV prevention strategies

↓ anesthesia-related RF's

Consider regional anesthesia where appropriate
Propofol for induction/maintenance where appropriate
Avoid/minimize N20 and volatile agents
Avoid/minimize postop opioids
Avoid high-dose neostigmine
Adequate hydration

 

PONV risk stratification and management

Low risk

No prophylaxis→treat PONV when it occurs.

 

Intermediate risk

Choose 1–2 interventions

 

High risk

Choose 2 interventions

 

P.B-7

Suggested Reading

  1. Gan TJ, Meyer TA, Apfel CC, et al: Society for ambulatory anesthesia guidelines for management of postoperative nausea and vomiting. Anesth Analg2007; 104:1082–89.

Venous Thromboembolism (VTE) Prophylaxis (Adapted from Geerts et al, 2004)

Clifford Schmiesing

VTE Risk Factors and Prevention Strategies

Weak

Moderate

Strong

Varicose veins

Cancer or myeloproliferative disorders

Surgery (e.g., hip/leg fx)

Immobility

Central venous catheterization

Major trauma

↑Age

Hypercoagulable state

Spinal cord injury

Acute medical illness

Pregnancy postpartum

 

Smoking

Estrogen therapy

 

Inflammatory bowel disease

Heart or respiratory failure

 

Obesity

Oral contraceptives

 

Pregnancy

Previous VTE

 

 

Malignancy

 

Level of risk

Successful prevention strategies

Risk profiles/examples

Low risk

No specific prophylaxis, early and “aggressive” mobilization

Minor surgery in patients < 40 yr with no additional risk factors.

Moderate risk

LDUH (q 12 h), LMWH (= 3400 U daily), GCS, or IPC

Minor surgery in patients with additional RFs or surgery in patients 40–60 yr with no additional RFs.

High risk

LDUH (q 8 h), LMWH (> 3400 U daily), or IPC

Surgery in patients > 60 yr or age 40–60 with additional RFs (prior VTE, cancer, hypercoagulable, etc.)

Highest risk

LMWH (> 3400 U daily), fondaparinux, oral VKAs (INR, 2–3), or IPC/GCS + LDUH/LMWH

Surgery in patients with multiple RFs (age > 40 yr, cancer, prior VTE), or hip or knee arthroplasty, HFS major trauma; SCI

P.B-8

Abbreviations: DVT: deep-vein thrombosis; GCS: graduated compression stockings; HFS: hip fracture surgery; INR: international normalized ratio; IPC: intermittent pneumatic compression; LMWH: low-molecular-weight heparin; LDUH: low-dose unfractionated heparin (aka “minidose heparin”); SCI: spinal cord injury; VKA: vitamin K antagonist.

Suggested Reading

  1. Geerts, WH, Pineo, GF, Heit, JA. et al: Prevention of venous thromboembolism: the seventh ACCP conference on antithrombotic and thrombolytic therapy. Chest2004; 126:S338–S400.

P.C-1

Appendix C: Standard Perioperative Pain Management

Sean Mackey

Ian Carroll

Raymond R. Gaeta

Introduction

Pain during the periop period has recently become an area of significant focus. Of the > 25 million surgical procedures performed in this country each year, > 75% of patients experience pain, and > 80% of those experience moderate-to-extreme pain.5 These observations have led, in part, to the adoption of the new Joint Commission Pain Standards recognizing the rights of patients to appropriate assessment and management of their own medical needs.

The primary goals of periop pain management include the reduction of pain and suffering with consequent improvement in function. Poor pain control leads to problems, such as a decreased ability to ambulate, which increases the risk of thromboembolic phenomenon and fatal PE. Inadequate pain control after abdominal and thoracic surgeries leads to splinting, atelectasis, and risk of pneumonia. Furthermore, activation of the neuroendocrine stress response to surgical pain stimulates the anterior pituitary gland, releasing a cavalcade of stress hormones and catecholamines, which have been shown to have deleterious effects on postop outcomes. These effects include weight loss, fatigue, immunosuppression, thromboembolism and hypercoagulability, dysrhythmias, urinary retention, and impaired pulmonary function.2 As an additional consequence, the continuous afferent barrage of nociceptive signals induces changes in the spinal cord and brain, leading to a phenomenon of central hypersensitization or “wind-up,” which is thought to play a role in the perpetuation of pain after surgery and even the transformation of acute pain states into chronic ones.6 As we understand more of the effects of pain on organ function and the CNS during the periop period, we realize that, through optimal pain control, not only can we impact pain and suffering, but also improve the overall morbidity and mortality of our surgical patients.

Multimodality Analgesia

Acute pain specialists have not been particularly successful in eliminating a patient's postop pain using a single analgesic agent or technique. Instead, we have found that we can enhance patient satisfaction by using small amounts of multiple agents, each working to reduce nociception at different points along the pain processing pathways—a concept called“multimodality analgesia.” By utilizing small amounts of opiates, COX-2Is, and neural blockade together, side effects have been reduced and pain control and patient satisfaction improved. This concept is most effective when integrated with a periop rehab approach to surgery, which involves teams of surgeons, anesthesiologists, rehabilitation specialists, nurses, pharmacists, and other health care providers, all working together. It requires that the patient be given appropriate preop education, excellent periop nociceptive blockade and attenuation of the neuroendocrine stress response, postop exercise, and early enteral nutrition.1

Preemptive Analgesia

An important component of multimodality analgesia is the notion of preemptive analgesia. This concept has been well known to the basic science researchers, but has caused much confusion, and often disappointment, in clinical practice. Part of the problem lies in how the term has been used in the past—often applied only to the administration of an analgesic agent preop or preincision. In fact, while the term does imply an intervention before surgery, it has much more stringent requirements. Specifically, it implies providing antinociceptive measures preop and postop to prevent the establishment of central sensitization caused by incisional and inflammatory injuries. Preincisional, long-acting neural blockade and administration of NSAIDs or COX-2Is have been shown to significantly reduce postop pain and opiate requirements, as compared with initiating therapy after surgery. Clinical researchers also have demonstrated improvements in postop rehab of patients by using preemptive analgesia, particularly in lower-extremity orthopedic surgery. Preemptive analgesia also may reduce the development of chronic pain syndromes following surgery, due to reduction in central hypersensitization.4

The New Analgesic Paradigm

This concept utilizes preemptive and multimodal administration of COX-2Is, neural blockade, and sustained-release opiates to replace the current overreliance on potent, short-duration opiates for postop pain management. The combination of COX-2Is, which reduce nociceptive sensitization both peripherally and centrally with a high degree of safety, and neural conduction blockade can significantly reduce pain scores, parenteral opiate dose requirements,

P.C-2

and dose-dependent adverse events. When used in conjunction with a structured postop rehab program, these techniques can lead to decreased patient morbidity and mortality, increased patient satisfaction, decreased recovery time, and shorter hospitalization.1.3

Suggested Readings

  1. Kehlet H: Acute pain control and accelerated postoperative surgical recovery. Surg Clin North Am1999; 79(2): 431–43.
  2. Kehlet H: Manipulation of the metabolic response in clinical practice. World J Surg2000; 24:690–5.
  3. Kirsh E. Worwag E. Sinner M. Chodak G: Using outcome data and patient satisfaction surveys to develop policies regarding minimum length of hospitalization alter radical prostatectomy. Urology2000; 56(1):101–7.
  4. Kissin I: Preemptive analgesia. Anesthesiology2000; 93(4):1138–43.
  5. Warfield CA. Kahn CH: Acute pain management. Programs in U.S. hospitals and experiences and attitudes among U.S. adults. Anesthesiology1995; 83(5):1090–4.
  6. Woolf CJ, Salter MW: Neuronal plasticity: increasing the gain in pain. Science2000; 288(5472):1765–9.
  7. Leykin Y, Pellis T, Ambrosio C: Highlights in postoperative pain management. Expert Rev Neurother 2007; 7(5):533–45.

Standard Adult Postop Analgesics

Analgesics

Morphine
Meperidine
Hydromorphone
Fentanyl
Ketorolacsee note 2 below

2 mg/10 min, up to 10 mg iv
10 mg/10 min, up to 150 mg iv; not to exceed (NTE) 600 mg/d
0.5–1 mg/10–20 min, up to 6 mg
12.5–35 µg/5 min, up to 200 mcg iv
30 mg iv slowly; then 15 mg q 6 h × 3 d max

Epidural Analgesia

 

Lumbar Epidural

Thoracic Epidural

Loading dose

Morphine

Hydromorphone

Morphine

Hydromorphone

Lower extremities

2–3 mg

0.4–0.6 mg

Pelvis

3–4 mg

0.5–0.8 mg

1–3 mg

0.15–0.4 mg

Abdomen

5–7 mg

0.5–1 mg

2–3.5 mg

0.2–0.6 mg

Thorax

7–8 mg

0.5–1 mg

2–3.5 mg

0.4–0.8 mg

Infusion

Morphine

Hydromorphone

Morphine

Hydromorphone

Lower extremities

0.3–0.5 mg/h

0.1–0.2 mg/h

Pelvis

0.3–0.5 mg/h

0.1–0.2 mg/h

0.1–0.3 mg/h

0.1–0.15 mg/h

Abdomen

0.4–0.7 mg/h

0.2–0.3 mg/h

0.2–0.5 mg/h

0.1–0.2 mg/h

Thorax

0.5–1.0 mg/h

0.2–0.3 mg/h

0.2–0.6 mg/h

0.15–0.2 mg/h

Special considerations

  1. Concentrations of opioids used for epidural infusions (in preservative-free solution):
  • Morphine, 0.15 mg/mL
  • Hydromorphone, 0.05 mg/mL
  1. Ketorolac may impair hemostasis. Consult with the surgical team.

Epidural Anesthesia/Postop Analgesia

Surgical Site

Epidural Catheter Location

Initial Bolus of 0.5% Bupivacaine

Infusion Rate of 0.125% Bupivacaine

Thoracic or upper abdomen

T6-T8

4–6 mL

5–10 mL/h

Lower abdomen

T10

10 mL

15 mL/h

Hip or knee

L2-3

8 mL

10 mL/h

P.C-3

Special considerations

  1. Give initial bolus dose before incision. Then, if patient hemodynamically stable, give 1/2 bolus dose 30 min before end of surgery.
  2. In recovery room, [check mark]sensory level. If no sensory block. [check mark]whether catheter is functioning with 8 mL 2% lidocaine bolus. ([check mark] vital signs.) If thoracic epidural starts with 2 mL, redose with 2 mL q 5–10 min, up to 8 mL.
  3. Start infusions: If catheter is functional, as evidenced by loss of sensation, start: local anesthetic + opioid infusions (see table, above).
  4. Best results: Local anesthetics and opioids are mixed in line using two separate infusion pumps. Thus, if either causes side effects, one can be stopped without the other.

Patient-Controlled Analgesia (PCA) for Intravenous Administration

Loading dose

Morphine
Hydromorphone
Fentanyl

Titrate to comfort
Titrate to comfort
Titrate to comfort

Basal rate

Morphine
Hydromorphone
Fentanyl

0.5–1 mg/h
0.1–0.2 mg/h
5–10 mcg/h

PCA lock-out dose and time

Morphine
Hydromorphone
Fentanyl

1–2 mg q 10–15 min
0.1–0.2 mg q 10–15 min
5–10 mcg q 10–15 min

Typical orders

  1. Call anesthesiologist with any questions about PCA.
  2. Check respiratory rate q 1 h while PCA in use.
  3. Call anesthesiologist if respiratory rate < 10/min. If rate < 6/min, treat with naloxone 0.1–0.2 mg iv (may repeat, to 0.6 mg), push and assist ventilation while waiting for anesthesiologist.
  4. Encourage patient to ambulate 4–6 h after surgery (unless contraindicated).
  5. After PCA D/C'd, start po pain medications (per surgeon).
  6. If patient required a large loading dose, the PCA lockout dose may need to be increased. Expect patient to need about 1/3 loading dose q h. Change PCA dose or lockout time to permit this dosing.

Patient-Controlled Epidural Analgesia (PCEA)

Loading dose

Morphine
Hydromorphone
Fentanyl

2–3 mg
0.5–1.0 mg
50–75 mcg

Basal rate

Morphine
Hydromorphone
Fentanyl

0.2–0.5 mg/h
0.08–0.12 mg/h
5–10 mcg/h

PCA lock-out dose and time

Morphine
Hydromorphone
Fentanyl

0.1–0.2 mg q 10–15 min
0.02–0.06 mg q 10–15 min
5–10 mcg q 10–15 min

Special considerations:

  1. For thoracic epidural, decrease all doses by one-third; if high thoracic, decrease by one-half.
  2. Concentrations of opioids for epidural infusion (in preservative-free solution).

o    Morphine

0.15 mg/mL

o    Hydromorphone

0.05 mg/mL

o    Fentanyl

10 µg/mL

  1. Bupivacaine (0.125% @ 5–8 mL/h) may be added to the previously mentioned regimen for supplemental analgesia. Typically, the bupivacaine infusion is stopped on POD 1 to facilitate early ambulation. Thoracic epidural local anesthetic may be continued if it does not interfere with ambulation.

P.C-4

 

P.D-1

Appendix D: Standard Pediatric Anesthetic Management

STANDARD PEDIATRIC MONITORS (NONINVASIVE)

Blood pressure (BP)

 

 

Capnometry/capnography

Measurement of ETCO2 display of wave form

 

Gas analyzer (e.g., Raman, IR, or mass spectroscopy)

Measurement of respired gases and anesthetics

 

Electrocardiogram (ECG)

5-lead preferred

 

Esophageal or precordial stethoscope

Breath and heart sounds monitored; dysrhythmias and ↓BP detected

 

Nerve stimulator

Monitor status of neuromuscular blockade

 

Oxygen analyzer

Measurement of FiO2

 

Pulse oximetry

Measurement of O2 saturation; 2 pulse oximeters in neonates–1 preductal; 1 postductal

 

Temperature

Nasal, esophageal, rectal, or skin

 

Visual observation of patient

Skin color, pupils, temperature, edema, sweating, movement

 

Ventilator function monitors

PIP, TV, disconnect alarm, etc.

 

STANDARD PREOP FASTING (NPO) GUIDELINES

·         All solid foods and nonclear liquids (e.g., milk, infant formula, orange juice) should be withheld after midnight before scheduled surgery.

·         All clear liquids (and breast milk) should be given up to 3 h before scheduled surgery. Because breast milk has a relatively short transit time through the stomach, and to simplify—therefore, to increase compliance with—these guidelines, breast milk is considered a clear liquid.

·         In practice, nonemergency cases may proceed 6 h after solids and nonclear liquids and 2 h after clear liquids and breast milk have been ingested.

*NB: The following sections are guidelines only. Specific drugs and drug dosages should be individualized, based on the physiological and pharmacological status of the patient, including factors such as age, weight, medication, and concurrent diseases.

Premedication

  • In general, patients < 9 mo of age do not need sedative premedication. Infants < 1 mo and premature infants may require atropine 0.01–0.02 mg/kg iv or 0.02 mg/kg im before intubation. Minimum iv atropine dose = 100 mcg.
  • Older children (9 mo–10 yr) can be premedicated successfully by using po midazolam (0.5–0.75 mg) in syrup, grape Kool-Aid, or cherry-flavored acetaminophen elixir (10–15 mg/kg po) 20–30 min before surgery.
  • For patients > 35–40 kg, po lorazepam (0.03–0.05 mg/kg) or diazepam (0.1–0.15 mg/kg) may be given 60 min before surgery with a sip of water if needed.

Induction Techniques

Preinduction

 

1.     [check mark] anesthesia machine, suction, airway equipment, drugs.

2.     Attach monitors and verify function.

3.     Premedication: < 6–9 mo—consider atropine 0.01–0.02 mg/kg iv before laryngoscopy to prevent vagally mediated bradycardia.

Induction

 

Routes of administration:

1.     im: ketamine hydrochloride 3–5 mg/kg (with atropine 0.02 mg/kg)

2.     iv: Propofol      2–3 mg/kg
   STP      4–7 mg/kg

3.     Inhalational: sevoflurane (MAC = 3.3% for neonates and younger infants, 2.5% for older infants and children) and halothane (MAC = 0.87% for neonates, 1–2% for infants), in N2O (up to 70%)/O2. Increase inspired concentration of sevoflurane incrementally every 3 breaths (up to 8%) and halothane (up to 4%). Monitor BP and HR closely, especially if using halothane.

Muscle relaxation

 

1.     Rocuronium: 0.6–1 mg/kg iv; 1 mg/kg recommended for rapid sequence induction. If airway concerns exist, consider awake intubation, use of succinylcholine.

2.     Succinylcholine: 1–2 mg/kg iv or 2–4 mg/kg im (controversial*). May be useful for rapid-sequence intubations, especially if airway concerns exist.

3.     Vecuronium or pancuronium: 0.1 mg/kg iv

4.     Cisatracurium 0.1 mg/kg iv

5.     Deep sevoflurane or halothane anesthesia

Laryngoscope

 

Blade

Age

Miller 0

Neonate

Miller 1

6–9 mo

Wis-Hipple 1.5

9 mo–3 yr

Macintosh 2

1–4 yr

Macintosh 3 or Miller 2

> 4 yr

*Succinylcholine may trigger MH in susceptible patients or cause cardiac arrest in myopathic patients; therefore, many pediatric anesthesiologists avoid the use of succinylcholine.

P.D-2

Typical ETT Size at Different Ages

Age

Wt

Uncuffed ETT size

Cuffed ETT size

Premature
Newborn

1–3 kg
3–4 kg

2.5 or 3.0
3.5

n/a
3.0

≥ 6–8 mo

6–8 kg

3.5 or 4.0

3.0 or 3.5

≥ 8–16 mo

10–12 kg

4.0 or 4.5

3.5 or 4.0

2–3 yr

13–15 kg

4.5

4.0 or 4.5

6 yr

20

Formula (uncuffed tubes): 4+ (age/4) = ETT size (to allow for a slight leak when positive pressure is applied). For cuffed tubes, use 0.5 size smaller and inflate as necessary to attain leak of 20–30 cm H2O.

9 yr

30 kg

 

 

12 yr

40 kg

 

 

*NB: These ETT sizes are guidance only; prepare an ETT one size larger and one size smaller than the ETT size selected. [check mark] ET placement of tube by auscultation of breath sounds bilaterally. [check mark] depth of carina by auscultation over left axilla as ETT is slowly advanced. Withdraw and secure ETT 2 cm from position where diminution of breath sounds was first noted. Positive pressure leak between 20 and 30 cm H2O is desirable. Leaks < 20 cm may result in volume loss and difficulty in providing appropriate ventilation during critical phases intraop or postop. Conversely, leaks > 30 cmH2O may carry a higher risk of subglottic edema and/or stenosis. Cuffed ETTs may be used, provided that leak is maintained 20–30 cmH2O. Some flexibility is required here. Consider length of case, difficulty of placing ETT, and adequacy of ventilation. A throat pack may assist in decreasing the leak if tube exchange is not desired.

P.D-3

Maintenance Techniques

Inhalational anesthesia only

 

30–100% O2
+ 0–70% N2O. In preemies and for cases where N2O is contraindicated, air may be used to lower FiO2.
+ Isoflurane, sevoflurane or halothane, titrated to effect.
Consider warming and humidifying all gases for long cases. Warm room to 75–80°F for infants; 70–75°F for children.

Balanced anesthesia

 

30–100% O2
+ 0–70% N2O
+ ~0.5% isoflurane
or propofol (50–200 mcg/kg/min)
TIVA - propofol 100–200 mcg/kg/min, + remifentanil 0.1–0.2 mcg/kg/min +/- N2O if procedure allows. Consider including amnestic agents: midazolam, low-dose inhalational agents (e.g., sevoflurane, isoflurane).
   + morphine (0.05 mg/kg/h) or fentanyl (1–3 mcg/kg/h) + Dilaudid 2 mcg/kg/h
   + consider acetaminophen pr 30–40 mg/kg for pain control.
Temperature monitoring; forced air warming; fluid warming if volume/blood/resuscitation expected.
Fluid requirements LR/NS at maintenance:
   0–10 kg = 4 mL/kg/h
   +11–20 kg = 2 mL/kg/h
   +>20 kg = 1 mL/kg/h (e.g., 25 kg = 65 mL/h)
If continued muscle relaxation is required during the above maintenance techniques, several options are available. Always use a nerve stimulator to assess block before redosing.

Short-acting

 

Mivacurium         0.1 mg/kg → 6–10 min

Intermediate

 

Vecuronium         0.1 mg/kg → 25–30 min
Rocuronium         0.6 mg/kg → 30 min
Cisatracurium         0.1 mg/kg → 30 min

Long-acting

 

Pancuronium         0.1 mg/kg → 40–65 min

Emergence

1. Reverse muscle relaxant

 

As surgical conditions permit, reverse residual muscle relaxant (when at least 1 twitch is present in train-of-four) with one of the following:

·         Neostigmine 0.05–0.07 (maximum dose) mg/kg iv + glycopyrrolate 0.01 mg/kg iv, or

·         Edrophonium 0.5–1.0 (maximum dose) mg/kg iv + atropine 0.01 mg/kg iv.

Enlon Plus - 0.05–0.1 mL/kg is equal to edrophonium 0.5–1 mg/kg (max: 10 mg), atropine 0.007–0.014 mg/kg (max: 4 mg).

2. Nausea prophylaxis

 

Ondansetron 0.1 mg/kg iv or Metoclopramide 0.1 mg/kg iv (~1 h before emergence).
Dexamethasone 0.1 mg/kg can be considered (avoid in oncology patients due to special protocols).

3. O2

 

D/C N2O/volatile agents and administer 100% O2.

4. Suction

 

Suction oropharynx thoroughly.

5. Extubation

 

Laryngeal spasm is common in children; therefore, it is usual to extubate them when they are awake, moving all limbs, and breathing adequately. Infants and children with full stomachs or difficult airways must be extubated when they are fully awake. The pharynx and stomach should be suctioned thoroughly prior to extubation. If laryngeal spasm occurs, Rx with 100% O2 and CPAP or PPV. If spasm fails to resolve and hypoxemia occurs, give succinylcholine 0.1–0.5 mg/kg and administer PPV. Consider reintubation if hypoxemia fails to resolve quickly. Consider atropine 0.01–0.02 mg/kg iv before succinylcholine, to preempt bradycardia.

P.D-4

Pediatric Epidural Anesthesia

Epidural anesthesia may be combined with GA for infants and children undergoing surgery involving the lower extremities, abdomen, chest, or spine. Single-dose (“single-shot”) techniques may be used, or epidural catheters may be placed for longer procedures and to facilitate postop epidural analgesia (see below). Bupivacaine 0.25% ± epinephrine 1:200K is most commonly used intraop. For patients admitted following surgery, opioids (e.g., hydromorphone [Dilaudid]) are generally added, together with bupivacaine 0.1% (see p. E-6). Use saline-filled syringe for loss-of-resistance to minimize chances of VAE.

Techniques and Dosages

  1. Caudal
  • Single-shot: 22-ga iv catheter (< 5 yr), 20-ga iv catheter (> 5 yr), or 21–23-ga iv catheter may be inserted via sacrococcygeal membrane.
  • A test dose with 0.1 mL/kg (max 3 mL) lidocaine or bupivacaine + epinephrine 1:100K or 1:200K is given.
  • If epidural catheter is used, add 0.8 mL to test dose volume due to dead space volume of catheter.
  • Initial dose: 0.5 mL/kg for lower extremity/perineal/genital procedures; 1.0 mL/kg for abdominal procedures (max 10 mL)
  • Catheter technique: in patients < 10 kg, first dilate the epidural space with 5–10 U NS; then, a 20-ga epidural catheter may be inserted through 18-ga Critikon iv catheter and advanced so that tip is located near level of incision (e.g., ~17 cm from skin to T4 in infant). If resistance is met, it may be necessary to pull the catheter back slightly, together with the needle (to avoid shearing catheter), or repeat procedure.
  • Initial dose: 0.5 mL/kg, max 10 mL.
  1. Lumbar
  • 17- or 18-ga epidural needle inserted via L3-4 or L4-5 interspace for single-shot injection or placement of 20-ga epidural catheter.
  • Use loss-of-resistance technique with fluid-filled syringe (air may cause VAE).
  • Good estimate of depth to epidural space is 1 mm/kg, up to ~30 kg.
  • Catheter should be threaded ~4 cm (maximum) beyond tip of needle.
  • A test dose with 0.1–0.2 mL/kg lidocaine or bupivacaine + epinephrine 1:100K or 1:200K is given.
  • Initial dose: 0.5 mL/kg for lower abdominal procedures; 1.0 mL/kg for upper abdominal and thoracic procedures
  1. Thoracic
  • The technique described for lumbar epidural catheter placement may be used between T6 and T12 in children.
  • A test dose with 0.1–0.2 mL/kg lidocaine or bupivacaine + epinephrine 1:100K or 1:200K is given.
  • Initial dose: 0.5 mL/kg, max 5–7 mL.
  • Local anesthetic-dosing guidelines same as above (note that volume will be ~1/3 less than with caudal approach.

For indwelling catheter techniques, hourly maintenance doses of half the initial dose may be given. For continuous infusion, maximum rate for bupivacaine is 0.5 mg/kg/h (0.3 mg/kg/h for neonates).

Pediatric Spinal Anesthesia and Analgesia

Spinal anesthesia is used primarily for procedures such as inguinal herniorrhaphy in former preterm infants at risk for postop apnea following GA. By avoiding GA, the incidence of postop apnea is reduced, but not eliminated. In most patients arriving in the OR without iv access, an iv may be inserted in a lower extremity immediately following placement of the spinal anesthetic, as little change in BP or HR occurs in infants < 6 mo of age.

After standard monitors are applied, the infant is placed in a supine or lateral decubitus position. Care is taken to avoid neck flexion, which may cause airway obstruction. The skin is infiltrated with 1% lidocaine using a 27- or 30-ga needle. Lumbar puncture is performed with a 22-ga 1.5” spinal needle to an average depth of 1.5 cm from skin. The most commonly used local anesthetic for spinal anesthesia in infants is tetracaine 1.0%, mixed with an equal volume

P.D-5

of 10% dextrose in a dose of 0.8–1.0 mg/kg. Epinephrine 1:1000 0.01 mL/kg is added. This dose usually provides adequate anesthesia for 90–120 min for inguinal herniorrhaphy.

Complications include high spinal anesthesia requiring tracheal intubation. PDPH is very uncommon in children < 12 yr of age, and probably rare in infants.

Suggested Readings

  1. Alifimoff JK, Cote CJ: Regional anesthesia. In A Practice of Anesthesia for Infants and Children. Cote CJ, Ryan JF, Todres ID, et al., eds. WB Saunders, Philadelphia: 1993, 429–49.
  2. Sethna NF, Berde CB: Pediatric regional anesthesia. In Pediatric Anesthesia, 4th edition. Gregory GA, ed. Churchill Livingstone, New York: 2002, 267–316.
  3. Yaster M, Krane E, Kaplan R, et al: The Pediatric Pain and Sedation Handbook. Mosby-Year Book, St. Louis: 1997.
  4. Motoyama EK, Davis PJ: Smith's Anesthesia for Infants and Children, 7th edition. Elsevier, Philadelphia: 2006, 255–396.

P.E-1

Appendix E: Standard Pediatric Postoperative Pain Management

Katie Larkin

Julie Good

Brenda Golianu

Traditionally, children have been undermedicated for their pain because of difficulty with assessment, concerns for safety, and lack of understanding of the physiologic consequences of untreated pain. There is now strong evidence that it is not only safe, but also beneficial to treat children's procedural pain. For example, infants have adverse behavioral cardiorespiratory and neuroendocrine responses to pain, which improve when appropriate analgesia is administered.

Pain assessment

 

Unlike most adults, infants and children < 7 yr have difficulty understanding and using a Visual Analog Scale (VAS). A frequently used tool for assessing pain in children 3–7 yr old is the Wong-Baker Faces Scale (Fig. E-1). For infants and nonverbal children, observational scales that rely on behavioral and/or physiologic parameters are often used (e.g., the FLACC Pain Scale, Fig. E-2, PIPP, NIPS, CHEOPS, CRIES as well as appropriate translations). The “gold-standard” of pain measurement is to solicit a direct subjective report from the child whenever possible.

Oral medications

 

For simple outpatient procedures, such as tonsillectomy, hernia repair, circumcision, or closed reduction of a fracture, a weak oral opiate, in combination with acetaminophen, is appropriate (see chart for dosing examples, p. E-4).

Intravenous medications

 

Patient Controlled Analgesia (PCA) can be considered in patients > 5 yr who are expected to remain hospitalized overnight, especially in those who are unlikely to tolerate oral intake in the initial hours after surgery (see initial dosing chart, p. E-4). For younger children, a Nurse Controlled Analgesia (NCA) can be employed. When the patient begins oral medications, D/C the basal rate but continue to provide the lockout dose for several more hours to be sure that the child is tolerating the oral medication. For opioid-related side effects such as nausea and vomiting, ondansetron can be added (0.1 mg/kg q 6 h to maximum of 4 mg q 6 h), and for pruritus, diphenhydramine (0.5 mg/kg q 6 h max 50 mg), or nalbuphine (0.05 mg/kg q 6 h max 20 mg), especially effective for epidural opioid-related pruritus. For respiratory depression, naloxone can be carefully titrated beginning at 0.001 mg/kg q 1–2 min as needed to restore adequate respiratory effort and wakefulness. Care must be taken, as the naloxone will have a short half-life (10–15 minutes), and respiratory depression may recur. Reversal of analgesia may also occur if naloxone is administered for treatment of pruritus or respiratory depression.

Adjuvant medications

 

In addition to opiates, several adjuvant medications are useful in the periop period. Lorazepam (Ativan) 0.025 mg/kg iv q 6 h is useful in preventing spasms and lessening fear in an unfamiliar environment. It is important to remember that lorazepam has a half-life of up to 16 h and doses can be additive.
Another useful adjuvant is ketorolac (Toradol) 0.5 mg/kg, up to a maximum of 30 mg loading dose, followed by 15 mg iv q 6 h, up to 72 h. Ketorolac is not recommended in patients with poor renal function or following surgeries where there is a large bleeding surface or complex bone repair. Ketorolac has been shown to cause delay in bony fusion in animal models, but conflicting information has been presented in humans. It also has been reported to cause acute renal failure with prolonged use, and is not recommended for use in bariatric patients due to its potential adverse impact on renal function. Given these concerns, it is helpful to observe hydration status, Plt count, and Cr, and discuss the use of this medication with the surgical team.
Other adjuvants to consider include acetaminophen po (10–15 mg/kg/dose q 6 h) or pr (20 mg/kg/dose q 6). An initial loading dose of 30–40 mg/kg pr administration for post-op pain may be helpful. Ibuprofen 10 mg/kg po dose also may be used. Medications to manage side effects, such as pruritus, N/V, constipation, and respiratory depression are presented in detail on the PCA order form, p. E-5.

P.E-2

 

Figure E-1. Wong-Baker Faces Scale used in pain assessment in children (and other patients developmentally from 3–7 years-old). The higher the score, the greater the child's pain. (After Wong DL, Bakr CM: Pain in children: comparison of assessment scales. Pediatr Nurs 1988; 14:9.)

Epidural pain management

 

In children, it is generally considered safer to place epidurals after induction of GA to avoid movement during placement. For children 0–12 mo, a caudal technique can be used. The patient is placed in the lateral decubitus position, the caudal anatomy is identified, and an 18-ga iv catheter is used to enter the caudal space. The catheter is advanced and aspirated. The space is then dilated with 5–8 ml of preservative-free NS. A 20-ga epidural catheter is then advanced to the desired location, or until obstruction is felt (~10–15 cm). The catheter tip may be visualized using ultrasound or nerve stimulation, if available. The catheter is taped secured with a moisture-resistant dressing, as it can easily become dislodged with regular activity. A test dose is given (lidocaine 1.5% with 1:200,000 epinephrine 0.1 ml/kg + 0.8 ml for the dead space of the catheter). Lumbar and thoracic epidurals can be placed in children > 10–12 mo. or earlier in experienced hands. Contraindications for epidural catheters include infection at the local site, coagulopathy, low Plt, sepsis, progressive neurologic deficit, and refusal of patient or parent.
Epidural placement should be checked by syringe aspiration before starting the infusion. Return of any bloody fluid or > 0.5 ml clear aspirant necessitates further evaluation before use of the catheter for pain control. Patients with indwelling epidural catheters may receive postop analgesia with either continuous infusion alone of continuous infusion with intermittent bolus dosing (patient-controlled epidural analgesia [PCEA]). Similar to PCA, PCEA can be used in ages ≥ 5–7 yr. Typical starting infusions are discussed in the table below. Medication dosage will depend on patient's age, location of surgical pain, catheter insertion level, and catheter tip location.
A bolus dose equivalent to the hourly volume of infusion may be given when a patient is uncomfortable. Increase the infusion by 10% to maintain the new level of analgesia. Infusion should not exceed 0.3 ml/kg/h in children ≥ 6 mo or 0.5 ml/kg/h in older patients. If inadequate analgesia persists after two dosing increases, it may be appropriate to abandon this form of treatment in favor of systemic analgesia. Do not leave a patient in pain for an extended period of time trying to “fix” an epidural catheter. If in doubt, check catheter placement then bolus catheter with 2% lidocaine w/ 1:200,000 epi 0.1 ml/kg to determine if a level is able to be obtained.

Peripheral Nerve Catheters

 

Increasingly, peripheral nerve catheters are being employed for peri-operative pain control. Local anesthetic infusions (bupivacaine 0.1% or ropivacaine 0.2%) are continued for 3–5 days postop.

         

P.E-3

 

Figure E-2. FLACC Pain Scale for pain assessment in non-verbal patients. By Merkel S, Voepel-Lewis T, Shayevitz JR, Malviya S. et al. Am J Nursing 2002; 102:55–8.

Suggested Readings

  1. Anand KJ, Carr DB: The neuroanatomy, neurophysiology, and neurochemistry of pain, stress, and analgesia in newborns and children. Ped Clin North Am1989; 36(4):795–822.
  2. Williams DG, Patel A, Howard RF: Pharmacogenetics of codeine metabolism in an urban population of children and its implications for analgesic reliability. Br J Anaesth2002; 89(6):839–45.
  3. Mello SS, Saraira RA, Marques RS, et al: Posterior lumbar plexus block in children: a new anatomical landmark. Reg Anesth Pain Med2007; 32(6):522–7.
  4. Ecoffey C: Pediatric Regional Anesthesia–update. Curr Opin Anaesthesiol2007; 20(3):232–5.
  5. Giaufre E, Dalens B, Gombert A: Epidemiology and morbidity of regional anesthesia in children: a one-year prospective survey of the French-Language Society of Pediatric Anesthesiologists. Anesth Analg1996; 83(5):904–12.
  6. Ilfeld BM, Morey TE, Wang RD, et al: Continuous popliteal sciatic nerve block for post-operative pain control at home: a randomized, double-blinded, placebo controlled study.Anesthesiology2002; 97(4):959–65.

P.E-4

Standard Pediatric Postop Analgesics and Antiemetics

 

Patient-Controlled IV Analgesia (PCA)

In a setting with trained nursing supervision, PCA can be used safely by children ≥ 5 yr old (about the age they are able to play video games). The lockout time usually is set at 10 min, but can be as short as 5 min for fentanyl. Common PCA medications and recommended starting doses in opiate-naive patients are listed below, followed by typical order for iv PCA.

Common PCA Medications

Medication

Loading dose

Basal Rate

Patient-controlled bolus

Morphine (1 or 5 mg/ml)

0.03 mg/kg

0.01 mg/kg/h

0.02–0.03 mg/kg

Hydromorphone (100 mcg/ml)

5 mcg/kg

1 mcg/kg/h

2 mcg/kg

Fentanyl (50 mcg/ml)

0.3 mcg/kg

0.1 mcg/kg/h

0.2–0.3 mcg/kg

Continuous iv infusion: When PCA is not practical (e.g., in children unable to understand PCA), continuous iv infusion of opiates may be used. Morphine infusion of 10–30 mcg/kg/h results in serum concentrations of 10–22 ng/ml and provides adequate analgesia. A common technique is to initiate iv morphine infusion with 1 mg/kg of morphine in 100 ml of D5W at 1 ml/h (the effective infusion rate is 10 mcg/kg/h). The infusion rate is slowly increased to provide adequate pain relief.

P.E-5

 

P.E-6

Postoperative Epidural Analgesia

Patients with indwelling epidural catheters may receive postop analgesia with either continuous infusion alone or continuous infusion with intermittent bolus-dosing (patient-controlled epidural analgesia [PCEA]). The infusate may be either local anesthetic with an opioid, local anesthetic alone, or opioid alone. At Stanford, the most commonly used epidural infusate for continuous infusion is bupivacaine 0.1% with hydromorphone 3 mcg/ml. In patients receiving PCEA, bupivacaine 0.1% with hydromorphone 25 mcg/ml is often used (see Typical Orders for Continuous Epidural Analgesia and Epidural PCA, pp. E-7, E-8).

At Stanford, patients receiving epidural analgesia are managed by the Pediatric Pain Service.

Hydromorphone (Dilaudid): May bolus dose 5–10 mcg/kg or just add to continuous infusion. Reduced dose for thoracic catheters.

When opioid epidural analgesia is indicated, hydromorphone is most commonly used because:

  1. It causes less itching and nausea, compared with morphine.
  2. It is more water soluble than fentanyl (decreased systemic absorption, spread over more dermatomes).
  3. It is less water soluble than morphine (thereby minimizing late respiratory depression).

Starting Doses for Epidural Infusion

Age

Starting dose

0–6 mo

hydromorphone 3 mcg/ml + 0.1% bupivacaine @ 0.1–0.15 ml/kg/h (max bupiv 0.3 mg/kg/h); for neonates, consider 0.1% bupivacaine infusion only

6 mo–3 yr

hydromorphone 3 mcg/ml + 0.1% bupivacaine @ 0.1–0.15 ml/kg/h (max bupiv 0.5 mg/kg/h)

3–7 yr

hydromorphone 3–5 mcg/ml + 0.1% bupivacaine @ 0.1–0.15 ml/kg/h (max bupiv 0.5 mg/kg/h)

≥ 7 yr

hydromorphone 5–10 mcg/ml + 0.1% bupivacaine @ 0.1–0.15 ml/kg/h + 0.05 ml/kg/h PCEA dose q 30 min lockout (max bupiv 0.5 mg/kg/h)

Notes:
In general, use a lower concentration of opiate infusion for neonates. When spread is desired (for surgeries with incisions that cross multiple dermatomes or when catheter placement is below the level of anticipated pain), a lower concentration and higher volume infusion may be desired.

Suggested Readings

  1. Alifimoff JK, Cote CJ: Pediatric regional anesthesia. In A Practice of Anesthesia for Infants and Children. Cote CJ, Ryan JF, Todres ID, et al., eds. WB Saunders, Philadelphia: 1993, 429–49.
  2. Yaster M, Krane E, Kaplan R, et al: The Pediatric Pain and Sedation Handbook. Mosby-Year Book, St. Louis: 1997.
  3. Ivani G, Mosetti V: Regional anesthesia for post-operative pain control in children: focus on continuous central and perineural infusions. Paediatr Drugs2008; 10(2):107–14.

P.E-7

 

P.E-8

 

P.F-1

Appendix F: Table of Drug Interactions

Sandra Leigh Bardas

This table is intended only as an advisory overview of potential interactions between various drug classes that patients may be taking preop and the drugs used in anesthetic practice. It is not intended to be a comprehensive list. Drug interactions are dynamic and manifest via a variety of circumstances including dosage, duration of administration as well as the patient's genetics and current physiologic state. An excellent source for the predictive values of drug interactions due to altered metabolism can also be found in references for inhibitors, inducers, and substrates of the Cytochrome P450 Enzymes. In view of the constant flow of new drug information, the reader is strongly urged to check the primary literature of each drug or online resources, such as DRUG-REAX, Lexi-Interact and Facts and Comparisons for drug interactions and then tailor drug usage to the patient specific clinical situation.

Preop Drug or Drug Class

Anesthetic Drug or Drug Class

Interaction

Clinical Management

Adrenergic agonists (Sympathomimetics)

Inhalation anesthetics

↑ risk of dysrhythmia

Monitor rhythm.

Alteplase

Nitroglycerin

Impaired thrombolytic effect

Avoid combination.

Alfentanil

Propofol

Opisthotonus, seizure

Avoid combination.

Aminoglycosides

Fluorinated inhalation agents

↑ potential for nephrotoxicity 2° to fluoride

Monitor renal function postop.

NMR (nondepolarizing muscle relaxants)

↑ blockade, possible prolonged respiratory depression

Support respiration.

Succinylcholine

↑ depolarizing blockade

Delay administration of aminoglycoside for as long as possible after recovery. Support respiration.

Amiodarone

Inhalation anesthetics

Enhanced myocardial depression and conduction defects

Monitor HR and rhythm.

Phenylpiperidone derivative opiate agonists (alfentanil, fentanyl, sufentanil)

↓ HR, ↓ BP, sinus arrest

Monitor hemodynamic function. Administer inotropic, chronotropic, and pressor agents as indicated. Large doses of vasopressors may be required. Bradycardia usually not responsive to atropine.

Amphetamines

Opiate agonists

↑ analgesia

Titrate dose of opiate.

Antacids

Oral medications

Delayed drug absorption 2° to delayed gastric emptying

Avoid administration within 2 h of each other.

Anthracyclines including doxorubicin, daunorubicin, idarubicin, epirubicin

Isoflurane

Prolonged QT interval

Monitor HR & rhythm.

Antibiotics, polypeptide (bacitracin, capreomycin, colistimethate, polymyxin B)

NMR, Succinylcholine

↑ blockade, possible prolonged respiratory depression Colistimethate and polymyxin B may have independent NMB activity.

Support respiration. Consider calcium gluconate to reverse blockade prolonged by colistimethate.

Anticholinergics, including drugs with an anticholinergic adverse effect profile

Opiate agonists

Potential for central or peripheral anticholinergic syndrome

Monitor for effects.

Anticholinesterase inhibitors, including donepezil, galantamine, rivastigmine, tacrine + opthalmics

Succinylcholine
Mivacurium

Blockade may be prolonged or antagonized.

Titrate to therapeutic effect. Monitor and support respiration.

 

NMR

↓ blockade

Titrate to therapeutic effect

Antifungal agents, azole systemic (fluconazole, itraconazole, ketoconazole, voriconazole)

Alfentanil

Inhibition of alfentanil metabolism

Monitor for respiratory depression. Consider lower dosage.

Midazolam

Prolonged CNS depression

Titrate midazolam to effect. Consider lower dosage

Aprotinin

NMR

Prolonged or recurring apnea

Monitor respiratory status.

Aprepitant

Phenylpiperidone derivative opiate agonists

↑ opiate effect

A lower dose may provide appropriate analgesia.

Aprepitant

Midazolam

↑ midazolam effect

A lower dosage may provide appropriate sedation.

Arsenic Trioxide

Inhalation Anesthetics

Prelong QT Interval

Monitor HR & Rhythm

Atorvastatin

Midazolam

↑ midazolam effect

A lower dosage may provide appropriate sedation.

Barbiturates

Inhalation anesthetics

↑ respiratory depression

Monitor and support respiration.

 

Ketamine

↑ respiratory depression

Monitor and support respiration.

Meperidine

Possible increase in normeperidine formation

↓ analgesic duration ↑ potential for seizure

Midazolam

Synergy

Monitor for CNS depression.

Opiate agonists

↑ respiratory depression

Monitor and support respiration.

Benzodiazepines

Barbiturates

Synergy

Titrate doses.

Bupivacaine

Sz threshold raised masking signs of toxicity

Monitor for symptoms of bupivacaine toxicity.

NMR

May prolong or antagonize blockade

Monitor and support respiration.

Opiate agonists

May decrease respiration and BP

Monitor and support respiration and BP.

Beta Blockers

NMR

May potentiate, delay or antagonize blockade

Titrate to effect. Monitor and support respiration.

Bosentan

Propofol

Propofol is a CYP3A4 strong inhibitor

Monitor ↓ BP

Botulinum toxins

NMR

↑ blockade

Titrate NMR to therapeutic effect.

Bupivacaine

Chloroprocaine

Enhanced bupivacaine toxicity

Avoid combination!

Calcium channel blockers

NMR

↑ blockade

Titrate NMR to therapeutic effect.

Propofol

↓ BP

Monitor BP

Calcium channel blockers-nondihydropyridine (diltiazem, verapamil)

Phenylpiperidone derivative opiate agonists

Enhanced bradycardia and ↓ BP

Monitor HR & BP

Midazolam

Enhanced midazolam effect

Consider dose reduction of midazolam

Carbamazepine

Diltiazem, Verapamil

Potential for CNS toxicity

Monitor for symptoms of CNS toxicity.

Midazolam

↓ effect of midazolam due to enzyme induction

Titrate midazolam to effect.

NMR

↓ blockade

Titrate NMR to therapeutic effect.

Cimetidine

Opiate

↑ CNS depression due to possible CYP 3A4 interaction

Titrate opiate to effect. If needed use naloxone.

Clindamycin

NMR

↑ blockade

Avoid combination if possible. Monitor and support respiration. Anticholinesterases or Ca++ may be beneficial.

Clonidine

Esmolol

Attenuation or reversal of antihypertensive effect

Monitor BP.

Clonidine, epidural

Local anesthetics

Prolonged sensory and motor blockade

Titrate dose of local anesthetics.

Conivaptan

Midazolam

Enhanced midazolam effect due to conivaptan strong CYP3A4 inhibition

Titrate to effect

Phenylpiperidone derivative opiate agonists

Enhanced opiate effect due to conivaptan strong CYP3A4 inhibition

Titrate to effect

Propofol

Enhanced propofol effect due to conivaptan strong CYP3A4 inhibition

Titrate to effect

Corticosteroids

Anticholinesterases

Possible antagonism of reversal agents

Monitor and support respiration.

NMR

Altered effectiveness of blockade

Titrate NMR to therapeutic effect.

Cyclophosphamide

Succinylcholine, Mivacurium

↑ blockade, even if patient received cyclophosphamide in past few weeks

Titrate to therapeutic effect. Monitor and support respiration.

Cyclosporine

NMR

↑ blockade

Titrate to therapeutic effect. Monitor and support respiration.

Dantrolene

Propofol

↑ muscle weakness due to inhibition of dantrolene metabolism

Monitor for hypotension.

Delavirdine

Phenylpiperidone derivative opiate agonists

↑ opiate effect

Consider dose reduction. Titrate to therapeutic effect.

Digoxin

Esmolol

↑ digoxin toxicity

Monitor for symptoms of toxicity.

NMR

Precipitate new dysrhythmias or potentiate existing dysrhythmias

Monitor rhythm.

Succinylcholine

Precipitate new dysrhythmias or potentiate existing dysrhythmias

Monitor rhythm.

Disulfiram

Inhalation anesthetics

Reduction in gas metabolism

Monitor for increased effect of inhalation agent.

Dobutamine

Inhalation anesthetics

Ventricular arrhythmias

Monitor HR and rhythm.

Dofetilide

Sevoflurane

Prolonged QT intervals

Monitor HR & rhythm

Echothiophate iodide (ophthalmic)

Succinylcholine

Prolonged blockade

Consider dose reduction or alternative NMB

Erythromycin (also see macrolide)

Midazolam

↑ CNS depression

Titrate dose of midazolam.

Esmolol

Alpha/Beta adrenergic agonists

↑ pressor effects

Infiltrating larger volumes of local anesthetics may have clinical relevance.

Estrogens

Succinylcholine

↑ blockade

Titrate NMR to therapeutic effect.

Ethanol

Barbiturates

Acute ingestion →CNS depression; chronic ingestion → tolerance

Avoid combination as tolerance is unpredictable.

Benzodiazepines

Acute ingestion →CNS depression; chronic ingestion →tolerance

Titrate dose of benzodiazepines.

Phenylpiperidone derivative opiate agonists

Chronic alcohol consumption→ pharmacodynamic tolerance

Titrate dose of opiate.

Fluvoxamine

Ropivacaine

Inhibition of CYP1A2 metabolism

Monitor for ropivacaine toxicity.

Furazolidone

Adrenergic agonists

↑ pressor sensitivity due to MAOI activity of furazolidone

Avoid combination! In hypertensive crisis, consider phentolamine.

Meperidine

Risk of MAOI/meperidine interaction

Avoid combination!

Gabapentin

General anesthetic agents

Case report of myotonia & dystonia

Monitor for potential adverse reactions.

Imatinib (tyrosine kinase inhibitor)

Midazolam

↑ midazolam effect

Consider dose reduction. Titrate to effect.

Propofol

↑ effect of propofol

Consider dose reduction. Titrate to effect.

Inhalation anesthetics, halogenated

Epinephrine

Increased cardiac irritability

Limit or reduce dosage of epinephrine with local anesthetics.

NMR

↑ blockade

Titrate dose of both agents.

Isoniazid (INH)

Enflurane

Fast acetylators of INH facilitate defluorination of enflurane →high output renal failure

Monitor renal function postop.

Halothane

↑ hepatotoxicity

Avoid giving rifampin-INH after halothane anesthesia.

Phenylpiperidone derivative opiate agonists

↑ opiate effect

Monitor for respiratory depression.

Ketamine

Halothane

↓ BP, ↓ CO

Monitor BP.

NMR

↑ blockade

Monitor and support respiration.

Labetalol

Beta-2 agonists

↓ bronchodilatation

Monitor for bronchospasm.

Inhalation anesthetics, halogenated

↓ BP

Monitor BP. Titrate anesthetic to effect.

Lidocaine

Cocaine

Possible ↓ in metabolic clearance of lidocaine

Monitor for lidocaine toxicity.

 

Meperidine

Risk of MAOI/ meperidine interaction

Avoid combination!

Linezolid

Adrenergic agonists

↑ pressor sensitivity due to MAOI activity of linezolid

Avoid combination! In hypertensive crisis, consider phentolamine.

Lithium

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Local anesthetics (large doses)

NMR

↑ blockade

Titrate NMR to effect. Monitor and support respiration.

Loop diuretics (including bumetanide, ethacrynic acid, furosemide, torsemide)

NMR

Blockade may be prolonged or antagonized; possibly dose-dependent, ↓ K+ → ↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Macrolide antibiotics including azithromycin, clarithromycin, erythromycin

Alfentanil

↑ effect of alfentanil

Titrate dose of alfentanil. Monitor and support respiration.

Macrolide antibiotics, including erythromycin, clarithromycin. But NOT azithromycin

Midazolam

↑ effect of midazolam

Titrate dose of midazolam. Monitor and support respiration.

NMR

Case reports of potentiation of blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Magnesium, parenteral

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Mercaptopurine

NMR

May ↓ or reverse blockade

Titrate NMR to therapeutic effect.

Methotrexate

Nitrous oxide

Potentiation of cytotoxic effects

Avoid before or during methotrexate treatment

Methyldopa

Ephedrine

↓ ephedrine effect

Consider alternative pressor agent.

Naloxone

Naloxone may precipitate a mild ↑ BP

Monitor BP.

Metoclopramide

Succinylcholine, NMR

↑ blockade

Titrate succinylcholine to therapeutic effect. Monitor and support respiration.

Monoamine oxidase inhibitor (MAOI); selective MAO Type B may have a lower risk.
Antidepressants MAOI: Isocarboxazid, phenelzine, tranylcypromine.
Anti-Parkinson agents MAO
Type B: rasagiline, selegiline

Meperidine

Agitation, Sz, diaphoresis, hyperpyrexia, coma, apnea

Avoid combination! Although other opiate agonists may not have these associated problems, monitoring is prudent.

Succinylcholine, mivacurium

↑ blockade

Titrate succinylcholine to therapeutic effect. Monitor and support respiration.

Sympathomimetics (including local anesthetic/epinephrine combinations, and cocaine)

Indirect- or mixed-acting sympathomimetic may cause severe HA, hyperpyrexia, or hypertensive crisis. (Direct-acting sympathomimetics appear to interact minimally.)

Avoid combination! Treat ↑ BP with phentolamine.

Muscle relaxants, skeletal

Anticholinesterase inhibitors

Possible severe muscle weakness

Monitor neuromuscular blockade. Titrate dose of anticholinesterase.

Nefazodone

Midazolam

↑ effect of midazolam due to strong inhibition of CYP3A4

Monitor and titrate to effect.

Phenylpiperidone derivative opiate agonists

↑ effect of opiate due to strong inhibition of CYP3A4

Monitor and titrate to effect.

 

Propofol

↑ effect of propofol due to strong inhibition of CYP3A4

Monitor and titrate to effect.

Nicardipine

Midazolam

↑ effect of midazolam due to strong inhibition of CYP3A4

Monitor and titrate to effect.

Phenylpiperidone derivative opiate agonists

↑ effect of opiate due to strong inhibition of CYP3A4

Monitor and titrate to effect.

Propofol

↑ effect of propofol due to strong inhibition of CYP3A4

Monitor and titrate to effect.

Nitrates, including NTG

Pancuronium

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Omeprazole

Midazolam

Possible enhanced ataxia or sedation due to ↓ clearance of midazolam

Monitor for prolonged effect of midazolam.

Opiate agonists

NMBs

↑ potential for opiate toxicity

Titrate dose of opiate.

Propofol

↓ BP

Titrate dose of each agent.

Succinylcholine

↓ HR

Monitor HR, heart block

Oxytocic drugs (including oxytocin, ergotamine, methylergonovine)

Adrenergic agonists

↑ BP 2° to synergistic vasoconstrictive effects

Titrate dosage. Monitor BP.

Pegvisomant

Opioids

Influences therapeutic efficacy of pegvisomant

May need dosage adjustment of pegvisomant.

Phenothiazines

Alpha/Beta adrenergic agonists

↓ alpha-adrenergic effects

Potential for dysrhythmias.

Barbiturate anesthetics

↑ neuromuscular excitation ↓ BP

Monitor BP.

 

Opiate agonists

↓ analgesic effect

Titrate opiate to effect.

Phenoxybenzamine

Local anesthetics

↑ absorption of local anesthetic

Titrate dose; possibly add epinephrine to local anesthetic.

Phenytoin (including fosphenytoin)

Midazolam

Enzyme induction

Titrate midazolam to effect. May need to ↑ dosage.

NMR

Reduced duration of blockade

Consider cisatracurium. Titrate NMR to therapeutic effect.

Phosphodiesterase 5 inhibitors (sildenafil, tadalafil, vardenafil)

Nitroglycerin

Enhanced vasodilation

Separate dose by at least 24 h (timing depends on specific agent) Half life may be prolonged by drug interactions, renal, hepatic impairment.

Piperacillin (including piperacillin/ tazobactam sodium)

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Probenecid

Thiopental

↑ CNS depression

Titrate dose of thiopental.

Procaine, procainamide

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Succinylcholine

↑ blockade 2° to competition for pseudocholinesterases

Titrate NMR to therapeutic effect. Monitor and support respiration.

Propofol

Alfentanil

Alfentanil may enhance the adverse effects of propofol

Monitor for opisthotonos and/or Sz.

Atracurium

Bronchospasm

Anaphylactoid-type reaction

Succinylcholine

↓ HR

Monitor HR. Consider atropine premed when propofol precedes succinylcholine.

Vecuronium

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Protease inhibitors except tipranavir

Phenylpiperidine derivative opiate agonists

↑ fentanyl levels due to CYP3A4 enzyme inhibition

Monitor respiration.

Midazolam

↑ midazolam levels

Titrate midazolam to effect. Contraindicated with amprenavir and ritonavir.

QTc Prolonging Agents
Public website for listing:
http://www.qtdrugs.org, International Registry Drug-Induced Arrhythmias; University of Arizona Health Sciences Center, Tucson, AR

Inhalation anesthetics

Effects can be additive with enhanced/advertise/toxic profile

Conduct a risk assessment Monitor rate and rhythm

Quinine, quinidine

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Succinylcholine

↑ blockade

Use this combination with caution.

Ranitidine

NMR

Possible resistance to NMR

Titrate dosage. Consider another NMR.

Rasagiline

Meperidine

Risk of MAOI/meperidine interaction

Avoid combination!

Reserpine

Sympathomimetics

↑ direct-acting agents; ↓ indirect-acting agents

Monitor BP.

Rifamycin derivatives including rifampin, rifabutin, rifapentine

Alfentanil

↑ clearance of alfentanil

Titrate alfentanil to effect. Increased dosage may be needed.

Halothane

↑ risk of hepatotoxicity

Avoid administration of rifampin-INH after halothane anesthesia.

Midazolam

Enzyme induction

Titrate midazolam to effect. May need to ↑ dosage.

Selective serotonin reuptake inhibitors (SSRIs)

Opiate agonists

Unknown mechanism

Monitor for serotonin syndrome.

Adrenergic agonist agents

Potential for serotonin syndrome

Monitor for serotonin syndrome.

Selegiline

Meperidine

Risk of MAOI/meperidine interaction

Avoid combination!

Sevoflurane

Drugs that prolong the QT interval

Synergy

Monitor heart rate and rhythm.

Sibutramine

Phenylpiperidine derivative opiate agonists

Package insert caution

Monitor for serotonin syndrome.

Sotalol

Sevoflurane

Prolonged QT intervals

Monitor rhythm.

Succinylcholine

Anticholinesterase inhibitors

↑ blockade

Use combination with caution. Titrate NMR to therapeutic effect. Monitor and support respiration.

Succinylcholine

Opioids

↓ HR

Monitor for bradycardia/heart block.

Tetracycline

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Theophylline

Halothane

↑ catecholamine-induced dysrhythmias

Use alternative inhalation agent.

Ketamine

Sz

Use combination with caution.

NMR

Resistance to blockade

Titrate NMR to effect.

Midazolam

↓ midazolam effectiveness

Titrate midazolam to effect.

Propofol

Possibly antagonized sedation

Titrate propofol to effect.

Thiazide diuretics

NMR

↑ blockade may be 2° to hypokalemia

Correct hypokalemia. Titrate NMR to effect.

Thiopental

Succinylcholine

Possible disseminated intravascular coagulation

Use large veins. Flush tubing with saline. Wait 2–3 min between administration.

Thiotepa

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Tricyclic antidepressants

Adrenergic agonist agents

↑ direct-acting agents;↓ indirect-acting agents

Monitor BP and rhythm. Effect unlikely in dose administered as infiltration with local anesthetics.

Fentanyl

Potentiation of fentanyl

Titrate opiate agonist to effect.

Trimethaphan

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Succinylcholine

↑ blockade

Avoid combination! Use nitroprusside instead.

Vancomycin

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

Succinylcholine

↑ blockade

Avoid administering vancomycin in the postanesthesia period.

Verapamil

Etomidate

↑ respiratory depression, apnea

Monitor and support respiration.

Midazolam

Deep and prolonged sedation

Monitor CNS and respiratory status.

NMR

↑ blockade

Titrate NMR to therapeutic effect. Monitor and support respiration.

P.F-2

P.F-3

P.F-4

P.F-5

P.F-6

P.F-7

P.F-8

P.F-9

P.F-10

Herbal Agents

It may be difficult to accurately predict the potential for drug interactions, because the majority of people neglect to inform health care providers of their consumption of herbal agents, natural remedies, alternative or complimentary medicines, nutritional supplements, and illicit substances. The significance of the potential interaction is also difficult to assess due to variations of botanical species, the different parts of plants that are used, assay of active ingredient(s), and product formulation. Herbs that alter hemostasis should be D/C'd 14 d before surgical, dental, or invasive procedures.

Plant

Precautions for Anesthesia and Surgery

Aloe vera

May impair hemostasis.

Bilberry (Vaccinium myrtillus)

May impair hemostasis.

Black cohosh (Cimicifuga racemosa)

Potential for hypotension.

Bladderwrack (Fucus vesiculosus)

May impair hemostasis.

Cat's Claw (Uncaria tomentosa)

May impair hemostasis.

Cayenne (Capsicum annum)

Has biological effect of ↑ catecholamine secretion.

Chamomile. German (Matricaria chamomilla)

May enhance CNS depression.

Coleus (Coleus forskohlii)

May impair hemostasis. Has potential for hypotension.

Devil's claw (Harpagophytum procumbens)

May have chronotropic and inotropic effects. May impair hemostasis.

Dong quai (Angelica sinensis)

May impair hemostasis. May cause vasodilation.

Echinacea

May increase the sedative effect of midazolam.

Ephedra ma huang (Ephedra sinica)

Potent sympathomimetic may cause cardiac arrhythmias.

Evening primrose (Oenothera biennis)

May impair hemostasis.

Fenugreek (Trigonella foenum-graecum)

May impair hemostasis. Contains coumarin.

Feverfew (Tanacetum parthenium)

May impair hemostasis.

Fish oils

May impair hemostasis.

Garlic (Allium sativum)

May inhibit Plt aggregation; potential for enhanced ↓ BP.

Ginger (Zingiber officinale)

May → prolonged bleeding time; possible ↑ catecholamine secretion; cardioactive in large and prolonged doses.

Ginkgo (Ginkgo biloba)

Selective antagonist of Plt aggregation; may cause vasodilation.

Ginseng, American (Panax quinquefolius)

May impair hemostasis.

Ginseng, Panax (Panax ginseng) root

Dose-dependent effects on BP. May cause tachycardia. May impair hemostasis.

Ginseng, Siberian (Eleutherococcus senticosus)

May impair hemostasis. Use barbiturates with caution. May affect BP.

Golden Seal (Hydrastis Canadensis)

May impair hemostasis. Potential for hypotension and bradycardia. May alter liver enzymes.

Grapefruit

Cytochrome P450 (CYP3A4) inhibition. Onset of midazolam may be delayed and action increased.

Grape seed (Vitis vinifera)

May impair hemostasis.

Green tea (camellia sinensis)

May impair hemostasis.

Guggul (Commiphora mukul)

May impair hemostasis.

Hawthorn (Crataegus oxyacantha)

High doses may cause hypotension + CNS depression.

Horse chestnut (Aesculus hippocastanum)

May impair hemostasis. Has cholinergic properties.

Kava kava (Piper methysticum)

Synergy with midazolam.

Licorice (Glycyrrhiza glabra)

May impair hemostasis. Mineralocorticoid effect

Melatonin

May enhance CNS depressants.

Passion flower (Passiflora spp)

Synergy with CNS depressants.

Red clover (Trifolium pratense)

May impair hemostasis. Contains coumarins.

Reishi (Ganoderma lucidum)

May impair hemostasis.

Schisandra (Schizandra chinensis)

Inducer of Cytochrome P450 enzyme system.

St. John's wort (Hypericum perforatum)

May have some MAOI activity. May reduce midazolam levels due to enzyme induction. Delayed emergence from anesthesia with propofol.

Tumeric (Curcuma longa)

May impair hemostasis.

Valerian (Valeriana officinalis)

Potentially synergistic with opiates & CNS depressants, including thiopental.

White willow (Salix alba)

Salicylate, may impair hemostasis.

Yohimbe (Corynanthe yohimbe) (Pausinystalia yohimbe)

May cause CNS stimulation. May have cardiovascular effects.

P.F-11

P.F-12

P.G-1

Appendix G: Special Considerations For Latex Allergy

Naiyi Sun

Brenda Golianu

Cathy Lammers

Alvin Hackel

Latex is the second most common cause of anaphylactic reactions under anesthesia (16.6% of cases).9 Latex gloves are the major source of latex proteins and are implicated in most cases of latex-mediated reactions.1 Latex exposure may occur through skin contact, mucous membrane exposure, inhalation, ingestion, or parenteral injection. Latex sensitization can lead to immune-mediated reactions, the most serious being type I IgE-mediated hypersensitivity reaction leading to life-threatening anaphylaxis.

Populations at Risk:

  • Patients with history of multiple surgical procedures including those with myelomeningocele, spina bifida, and congenital genitourinary tract anomalies.
  • Patients with a history of myelomeningocele and spina bifida should be treated with a “Latex precautions” regimen from birth, regardless of prior history of exposure or latex reactivity.
  • Health care personnel with occupational exposure.
  • Other individuals with occupational exposure such as rubber industry workers and hairdressers.
  • Patients with history of atopy, hay fever, asthma, or eczema.
  • Patients with history of food allergy to tropical fruits (such as avocado, kiwi, banana, mango) and chestnuts which contain cross-reacting proteins with latex.

It is currently estimated that as many as 17% of health care workers have been sensitized to latex.11 Occupational exposure can be minimized by avoiding powdered latex gloves and limiting the use of latex-containing gloves. Applying lotion to hands before using latex gloves facilitates the transfer of latex proteins to hands and should be avoided.

In high-risk patients, latex-avoidance protocols are recommended as this may decrease the incidence of subsequent intraoperative allergic reactions. Hospitals and ORs have decreased the use of products that contain latex to the extent that some are essentially latex-free. Anesthesia carts can be assembled with latex-free products, reducing the risk of latex-sensitization for all patients and negating the need for a special “latex-free cart.” The latex content of commonly used materials can be identified from external labeling, package inserts, or directly from the manufacturers. Even minimal latex exposure (e.g., an injection through a latex port of iv tubing or opening a package of powdered latex gloves) has resulted in anaphylaxis.

Diagnosis of latex allergy is based on a focused history and physical examination with positive in vivo or in vitro test. In vitro serum tests for latex-specific IgE such as RAST are highly specific but have a high false-negative rate, up to 30%.1 Skin testing identifies patients with a high titer of IgE to latex, but must be performed with appropriate safeguards because it may induce systemic anaphylaxis.

Pharmacological prophylaxis in the acute setting is controversial for patients with documented latex allergy. Prophylaxis medications, such as diphenhydramine, ranitidine, and hydrocortisone, are not universally successful in preventing latex anaphylaxis.12 Some authors have argued that pretreatment may mask the early immune responses leaving anaphylaxis as the first evidence of an allergic reaction.8

To prepare a latex-safe environment:

  • Notify OR nurses, anesthesia technicians, and surgical staff of the need for a latex-free room.
  • Place a sign on the door stating: “LATEX-FREE ROOM.”
  • Schedule the latex-allergic patient as the first case of the day to minimize the presence of airborne latex particles.
  • Set up the room with latex-free materials (e.g., bag, bellows, ECG electrodes, pulse oximeter clip, iv tubing without latex ports, vinyl gloves, vinyl BP cuffs, clear micropore tape).
  • Avoid bouffant surgical hair caps and shoe covers that contain latex bands.
  • Wrap latex tubing on stethoscope. BP cuff, or tourniquet with Webril or cotton gauze if they contain latex derivatives.
  • Removal of rubber stoppers from drug vials (instead of withdrawing through the stopper) is controversial.

P.G-2

Diagnosis of anaphylaxis or latex allergy:

  • Skin: urticaria at site of contact with latex product or generalized urticaria, and flushing.
  • Respiratory: bronchospasm, wheezing, → PIP, ↓ O2sat, upsloping of ETCO2 tracing.
  • Cardiac: ↓ BP, → HR, cardiac arrest.

Treatment of anaphylaxis:

  • 100% O2and manually ventilate if needed.
  • Discontinue all anesthetic agents.
  • Epinephrine 0.1–1 mcg/kg iv initially, with rapid escalation as needed to support BP, may require an epinephrine infusion (0.05 – 0.1 mcg/kg/min).
  • Administer iv fluid to → preload and support BP.
  • Stop administration of any suspected medications and remove latex products. (Instruct surgical staff to change to nonlatex gloves and remove any latex products from surgical field).
  • Administer steroids (hydrocortisone 100 mg or methylprednisolone 0.5 mg/kg), antihistamine (diphenhydramine 50 mg or 0.5 mg/kg iv), H-2 blockers (ranitidine 150 mg iv).
  • Administer bronchodilators (albuterol) via nebulizer for bronchospasm.
  • Continue steroids and diphenhydramine for 24–48 h or until symptoms resolve.
  • Consider drawing blood within 2 h of reaction to send for tryptase level (peaks at 30 min, t 1/2 is 2h) which is a mediator released from mast cells during degranulation.
  • Refer patient to allergist to follow up. Skin prick test or RAST can be performed (4–6 weeks after the acute reaction resolves) to specifically test for latex allergy.
  • Patients with a history of latex anaphylaxis should be advised to wear a Medic Alert bracelet.

Suggested Readings

  1. ASA Committee for Occupational Health of Operating Room Personnel: Natural Rubber Latex Allergy: Considerations for Anesthesiologists. 2005. Available at:http://www.asahg.org/PublicationsAndServices/latexallergy.html.
  2. Blum RH, Rockoff MA, Holzman RS, et al: Overreaction to latex allergy? Anesth Analg1997; 84:467–8.
  3. Hirshman CA: Latex anaphylaxis. Anesthesiology1992; 77:223–4.
  4. Holtzman RS: Clinical management of latex-allergic children. Anesth Analg1997; 85(3):529–33.
  5. Michael T, Niggemann B, Moers A, et al: Risk factors for latex allergy in patients with spina bifida. Clin Exp Allergy1996; 26(8):934–9.
  6. Rao AM, Davies MW: Syringes and latex allergy. Anaesthesia1997; 52(5):506.
  7. Vassallo SA, et al: Allergic reaction to latex from stopper of a medication vial. Anesth Analg1995; 80(5):1057–8.
  8. Hepner DL, Castells MC: Latex allergy: an update. Anesth Analg2003; 96:1219–29.
  9. Laxenaire MD, Mertes PM, et al: Anaphylaxis during anaesthesia. Results of a two-year survey in France. Br J Anaesth2001; 87(4):549–58.
  10. Zucker-Pinchoff B, Stadtmauer GJ: Latex allergy. M Sinai J Med2002; 69:88–95.
  11. Yassin MS, Lierl MB, Fischer TJ, et al: Latex allergy in hospital employees. Ann Allergy1994; 72:245–9.
  12. Setlock MA, Cotter TP, Rosner D: Latex allergy: failure of prophylaxis to prevent severe reaction. Anesth Analg1993; 76:650–2.

P.H-1

Appendix H: Perioperative Acupuncture

Jeannie Seybold

Emily Ratner

Brenda Golianu

Introduction

Acupuncture is a treatment modality that has been practiced in China for over 3 millennia. Initially transmitted as an oral tradition, it was first described in written form in the Huang Di Nei Jing or the Yellow Emperor's Inner Cannon, the seminal text of ancient Chinese medicine dating back to the 3rd century BC.4 Acupuncture involves placing very thin needles in the skin to stimulate the flow of qi in a complex network of meridians in the body. There are 12 principal and 8 curious acupuncture meridians that correspond to physiologic and anatomical organ functions.4 Qi is a dynamic form of physical and spiritual energy that flows within the universe and in all organisms. One of the basic tenets of Chinese medicine is that illness and pain are caused by the stagnation or blockage of qi flow and/or the invasion of pathological influences- traditionally known as wind, heat, cold, dampness, dryness, or fire that result in imbalances of yin and yang. When a point is needled, a heavy sensation known as “deqi,” or a mild paresthesia may be experienced by the patient. The practitioner may sense a gentle contraction of the connective tissue surrounding the needle, or may observe a flare developing around the needle. Needling, electrical and laser stimulation, acupressure or even herbal therapies (moxibustion or capsicum plaster) over specific points have all been documented to alleviate pain and pathological states.11 In addition to body acupuncture, which developed in China, Japan, and Korea, many different traditions have been developed that focus on needling specific body parts, that is, the ear, scalp, or hand, as microsystems representing the entire body. Acupuncture has been used to provide analgesia during surgery since the 1950s in China. However, it was little more than a curiosity in the United States before 1971, when reporter James Reston went to China to report on the diplomatic efforts of Henry Kissinger and President Richard Nixon. While in Beijing, Reston required an emergency appendectomy and received acupuncture for postoperative ileus and pain control. The popularity of acupuncture in the United States exploded after he published his experiences in the New York Times. In 1997, the NIH released a consensus statement supporting the use of acupuncture for adult postoperative and chemotherapy-induced nausea and vomiting and postoperative dental pain. It also stated that acupuncture may be a useful adjunctive treatment in addiction, stroke rehabilitation, headache, menstrual cramps, tennis elbow, fibromyalgia, myofascial pain, osteoarthritis, low back pain, carpal tunnel syndrome, and asthma. During the last 10 years, acupuncture has been increasingly studied and used to treat acute postoperative pain as well as in chronic pain clinics throughout the United States.28,29

Mechanisms

Several mechanisms for acupuncture analgesia have been proposed. The gate control theory by Melzack and Wall in 1965 postulated that stimulation of a-beta fibers inhibits a-delta and c fiber transmission of pain signals.15 This may be a local mechanism of action. Other studies have shown that electroacupuncture at low (2–4 Hz) and high frequencies (100 Hz and greater) selectively induces endorphin and enkephalin release, respectively.8 Conflicting evidence exists regarding the ability of naloxone to antagonize the analgesic effects of acupuncture. Some studies show that naloxone reverses acupuncture-induced analgesia, while others dispute this.3,18 This suggests the analgesic mechanisms of acupuncture are more complex than the release of endorphins. Additional evidence suggests that the frequency and intensity of stimulation determine the degree of naloxone-reversibility.9 A review of functional MRI and positron-emission tomography studies has shown that electroacupuncture exerts effects over the hypothalamus, somatosensory motor cortex, and rostral anterior cingulate cortex, with nonspecific modulation of the limbic system and hypothalamus.16 A recent study by Tsuchiya showed that acupuncture enhanced the local generation of plasma nitric oxide, increasing regional blood flow.24 Acupuncture may also have anti-inflammatory properties.33

Perioperative Use

Acupuncture is effective for reducing PONV.4,29 P6 (Neiguan), the most thoroughly studied acupoint, is located three fingerbreadths proximal to the wrist crease, between the flexor carpi ulnaris and palmaris longus tendons and directly over the median nerve. A Cochrane review of 26 randomized trials noted significant reduction in nausea and the need for rescue antiemetics with the use of P6 acupoint stimulation.14 Direct electrical stimulation of this point was shown to be as efficacious as a standard dose of ondansetron for PONV in adults and resulted in a 37% reduction in nausea in children after tonsillectomy.21 There is evidence that transcutaneous electrical acupoint stimulation

P.H-2

is also effective in reducing PONV.10 Stimulation of P6 by twitch monitoring using a standard nerve stimulator (at 1 Hz, 0.2 ms, 50 mA) during general anesthesia for laparoscopic surgery significantly reduced PONV for 24 hours with an efficacy similar to that of commonly used antiemetic drugs.1,22 A trained medical acupuncture practitioner would likely integrate P6 with a combination of body and ear acupuncture points to minimize PONV. Acupuncture has not been shown to eliminate the need for anesthetic medications during surgery, but it may be a useful adjuvant for perioperative analgesia and anxiolysis. In a randomized controlled trial of perioperative acupuncture for abdominal surgery, Kotani, et al. showed 50% reduction in postoperative morphine use, 20–30% reduction in postop nausea, and 30–50% reduction in plasma cortisol and epinephrine levels.12 A reduction in postoperative pain and analgesic requirements was also seen in studies of acupuncture in patients having gynecologic, abdominal, thoracic, and orthopedic surgeries.6,23,25,27Acupuncture is known to produce deep relaxation and sedation, and may be useful for preoperative anxiolysis or for postoperative weaning of narcotic medications in opioid tolerant patients.7,30 The risks of acupuncture are rare. The most common are minor bruising, limited capillary bleeding, pain or local infection at the needling site. Anesthesiologists can be trained to provide acupuncture treatment for PONV and anxiolysis. More comprehensive perioperative treatment should be performed by or under the supervision of a trained medical acupuncturist.

 

Figure H-1. P6 Acupoint. P6 is located three fingerbreadths proximal to the wrist crease directly over the median nerve and between the tendons of palmaris longus and flexor carpi radialis. For PONV prophylaxis, the two nerve stimulator electrodes can be placed over the median nerve at (1) a point proximal to the wrist crease (marked with an x) 2 cm proximal to P6, and (2) on P6 or 1 cm distal to the P6 point. Stimulus parameters: 1Hz, 0.2ms, 50 mA during anesthesia.

Suggested Readings

  1. Arnberger M, Stadelmann K, Alischer P, et al: Monitoring of neuromuscular blockade at the P6 acupuncture point reduces the incidence of postoperative nausea and vomiting.Anesthesiology2007; 107(6):903–8.
  2. Berman BM, Lao L, Langenberg P: Effectiveness of acupuncture as adjunctive therapy in osteoarthritis of the knee: a randomized, controlled trial. Ann Intern Med2004; 141(12):901–10.
  3. Chapman CR, Benedetti C, Colpitts YH, et al: Naloxone fails to reverse pain thresholds elevated by acupuncture: acupuncture analgesia reconsidered. Pain1983; 16:13–31.
  4. Chernyak GV, Sessler DI: Perioperative acupuncture and related techniques. Anesth Analg2005; 102(5):1031–78.
  5. Gan TJ, Jiao KR, Zenn M, et al: A randomized controlled comparison of electro-point stimulation or ondansetron versus placebo for the prevention of postoperative nausea and vomiting. Anesth Analg2004; 99(4):1070–5.
  6. Gilbertson B, Werner K, Russell LC, et al: Acupuncture and arthroscopic acromioplasty. J Orthop Res2003; 21(4):752–8.
  7. Golianu B, Krane E, Seybold J, et al: Non-pharmacological techniques for pain management in neonates. Sem Perinatology2007; 31(5):318–22.

P.H-3

  1. Han JS: Acupuncture and endorphins. Neurosci Lett2004; 361:258–61.
  2. Huang C, Wang Y, Han JS, et al: Characteristics of electroacupuncture-induced analgesia in mice: variation with strain, frequency, intensity and opioid involvement. Brain Res2002; 945:20–5.
  3. Kabalak AA, Akcay M, Akcay F, et al: Transcutaneous electrical acupoint stimulation versus ondansetron in the prevention of postoperative vomiting following pediatric tonsillectomy. J Alt Comp Med2005; 11(3):407–13.
  4. Kim KS, Nam YM: The analgesic effects of capsicum plaster at the Zusamli point after abdominal hysterectomy. Anesth Analg2006; 103(3):709–13.
  5. Kotani NK, Hashimoto H, Sato Y, et al: Preoperative intradermal acupuncture reduces postoperative pain, nausea and vomiting, analgesic requirement, and sympathoadrenal responses. Anesthesiology2001; 95(2):349–56.
  6. Kundu A, Berman BM: Acupuncture for pediatric pain and symptom management. Pediatr Clin North Am2007; 54:885–9.
  7. Lee A, Done ML: Stimulation of the wrist acupuncture point P6 for presenting postoperative nausea and vomiting. Cochrane Database Syst Rev2004; 3:CD003281. DOI:10.1002/14651858.CD003281.pub2.
  8. Lewith G, Kenyon JN. Physiological and psychological explanations for the mechanism of acupuncture as a treatment for chronic pain. Soc Sci Med1984; 19:1367–78.
  9. Lewith GT, White PJ, Pariente J: Investigating acupuncture using brain imaging techniques: the current state of play. eCAM2005; 2(3):315–9.
  10. Lin YC: Perioperative usage of acupuncture. Pediatr Anesthesia2006; 16:231–5.
  11. Mayer DJ, Price DD, Rafii A, et al: Antagonism of acupuncture analgesia in man by the narcotic antagonist naloxone. Brain Res1977; 121:368–72.
  12. NIH Consensus Statement Online: Acupuncture.1997 Nov 3–5; 15(5):1–34.
  13. Reston J: Now let me tell you about my appendectomy in Peking. New York TimesJuly 26,1971.
  14. Rusy LM, Hoffman GM, Weisman SJ: Electro-acupuncture prophylaxis of postoperative nausea and vomiting following pediatric tonsillectomy with or without adenoidectomy.Anesthesiology2002; 96:300–5.
  15. Scuderi PE: P6 Stimulation, a new approach to an ancient technique. Anesthesiology2007; 107(6):870–2.
  16. Sim CK, Xu PC, Pua HL, et al: Effects of electro-acupuncture on intra-operative and post-operative analgesic requirement. Acupunct Med2002; 20(2–3):56–65.
  17. Tsuchiya M, Sato EF, Inoue M, et al: Acupuncture enhances generation of nitric oxide and increases local circulation. Anesth Analg2007; 104:301–7.
  18. Vickers AJ, Rusch VW, Malhotra VT, et al: Acupuncture is a feasible treatment for post-thoracotomy pain: results of a prospective pilot trial. BMC Anesthesiology2006; 6:5.
  19. Ulett GA, Han SP, Hang JS: Electroacupuncture: mechanisms and clinical application. Biol Psychiatry1998; 44:129–38.
  20. Usichenko TI, Dinse M, Hermsen M, et al: Auricular acupuncture for pain relief after total hip arthroplasty: a randomized controlled study. Pain2005; 114:320–7.
  21. Wang SM, Kain ZN, White P: Acupuncture analgesia I: the scientific basis. Anesth Analg2008; 106:602–10.
  22. Wang SM, Kain ZN, White PF: Acupuncture analgesia II: clinical considerations. Anesth Analg2008; 106:602–10.
  23. Wang SM, Peloquin C, Kain Z: The use of auricular acupuncture to reduce preoperative anxiety. Anesth Analg2001; 93:1178–80.
  24. White P: Use of alternative medical therapies in the perioperative period: is it time to get on board. Anesth Analg2007; 104:251–4.
  25. Zhang RX, Li A, Liu B, et al: Electro-acupuncture attenuates bone cancer pain and inhibits spinal interleukin-1 beta expression in a rat model. Anesth Analg2007; 105:1482–8.
  26. Zhang RX, Lao LX, Wang XY, et al: Electroacupuncture attenuates inflammation in a rat model. J Alt Comp Med2005; 11(1):135–42.