Sukhijinder Dhother
Patient Position: Supine, with the extremity to be blocked supported on a side table extension.
Indications: Surgery of the arm below the level of the cuff, usually at or below the elbow. Duration is not to exceed 90 minutes.
Needle Size: 20-gauge, 150-mm intravenous cannula in dorsum of hand and away from surgical site.
Volume: 1 mL/kg up to 60 mL 0.5% lidocaine.
Anatomic Landmarks: A convenient distal vein away from the surgical site; distal vein of the hand.
Approach and Technique: Insert and secure an intravenous cannula (Fig. 21-1). Next, wrap the upper arm with a 10-cm Webril (Kendall Co., Boston, MA) padding band, and then apply an appropriate-sized pneumatic double cuff to the upper arm. The lower end of the distal cuff is secured with foam tape (10 cm) to prevent migration. Next, check the integrity of both cuffs by sequential inflation and deflation. The arm is elevated, and the patient is asked to close the hand firmly on a padding bandage. A 10-cm latex bandage is wrapped from distal to proximal to provide exsanguination of the limb (Fig. 21-2). The proximal (upper) tourniquet is inflated to 100 mm Hg above systolic pressure, or at least 250 mm Hg, and then the latex bandage is removed. Absence of brachial and distal pulses indicates correct function. Fifty milliliters of 0.5% lidocaine is injected slowly. The cannula is removed and the arm prepared for surgery. Adequate sensory anesthesia should be achieved in approximately 10 to 15 minutes.
Tips
1. To prevent local anesthetic toxicity reactions, the tourniquet should remain in place for at least 45 minutes.
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Figure 21-1. Insert and secure an intravenous cannula. |
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Figure 21-2. A 10-cm latex bandage is wrapped from distal to proximal to provide exsanguination of the limb. |
2. The patient should be asked to firmly close the hand around a 5-cm roll of tape. This allows better exsanguination of the hand.
3. It is best to provide a tourniquet effect proximal to the patient's wrist by wrapping the operator's hand around it.
4. Inject half the anesthetic solution and observe the distension and backward filling of the veins. The remaining volume is then injected after releasing the wrist to allow a proximal spread up to the level of the proximal cuff.
5. When the patient begins experiencing tourniquet pain, it is time to inflate the distal cuff and deflate the proximal cuff, up to an additional 30 minutes. Do not deflate the cuffs until at least 20 minutes after injection. Be vigilant for signs of systemic absorption during tourniquet release.
6. 0.2% ropivacaine or 0.125% levobupivacaine has been suggested as an alternative to 0.5% lidocaine. Their use prolongs the duration of the block.
7. The same technique can be used for lower extremity surgery below the knee.
Suggested Readings
Atanassoff PG, Aouad R, Hartmannsgruber MW, et al. Levobupivacaine 0.125% and lidocaine 0.5% for intravenous regional anesthesia in volunteers. Anesthesiology 2002;97:325–328.
Brown DL. Atlas of regional anesthesia. Philadelphia: WB Saunders, 1992.
Holmes CM. Intravenous regional anesthesia: a useful method of producing analgesia of the limbs. Lancet 1963;1:245.
Mulroy MF. Regional anesthesia: an illustrated procedural guide, 3rd ed. Philadelphia: Lippincott Williams & Wilkins, 2002.
