Principles of surgery

PART II
Specific Considerations

CHAPTER 40
Urology

BASIC SCIENCE QUESTIONS

1. The blood supply of the distal ureter is provided by branches of the

A. Aorta

B. Renal arteries

C. Lumbar arteries

D. Iliac arteries

Answer: D

The blood supply of the proximal ureter derives from the aorta and renal artery and comes mainly from the medial direction. However, once it crosses the iliac vessels at the pelvic brim near where the iliac vessels bifurcate, it derives its blood supply laterally from branches from the iliac arteries. The blood supply has implications for managing ureteral injuries. Mobilizing the distal ureter for anastomosis requires releasing its lateral attachments, which results in ischemia, so for this reason, distal ureteral injuries are typically managed by bringing the proximal ureter to the bladder. (See Schwartz 9th ed., p 1460.)

2. Which of the following does NOT supply arterial blood to the testes?

A. Testicular artery

B. Deferential artery

C. Scrotal artery

D. Cremasteric artery

Answer: C

The blood supply enters the testis at the superior pole by way of the spermatic cord. In addition to the vas deferens, the cord carries three separate sources of arterial blood flow—the testicular artery that branches from the aorta below the renal artery, the cremasteric artery, and the deferential artery. Interruption of one of the arteries during vasectomy or inguinal surgery will not result in ischemia to the testis.

The cremasteric artery is a branch of the inferior epigastric artery, and the deferential artery is a branch of the superior vesicular artery. There is no scrotal artery. (See Schwartz 9th ed., p 1461.)

3. Which portion of the bladder is intraperitoneal?

A. Dome only

B. Dome and body

C. Dome, body, and neck

D. None of the above

Answer: D

The urinary bladder is situated in the retropubic space in an extraperitoneal position. A portion of the bladder dome is adjacent to the peritoneum, so ruptures at this point can result in intraperitoneal urine leakage. (See Schwartz 9th ed., p 1460.)

4. Hydroceles form between

A. The external spermatic and cremasteric fascia

B. The cremasteric and internal spermatic fascia

C. The internal spermatic fascia and the parietal layer of the tunica vaginalis

D. The visceral and parietal layers of the tunica vaginalis

Answer: D

Beneath the skin of the scrotum, from superficial to deep, are the dartos, external spermatic, cremasteric, and internal spermatic fascias. These layers are not always distinct. Beneath the internal fascia are the parietal and visceral layers of the tunica vaginalis, between which hydroceles form. The visceral layer of the tunica vaginalis is adherent to the testis. (See Schwartz 9th ed., p 1461.)

5. The left spermatic vein drains into the

A. Left iliac vein

B. Left inferior epigastric vein

C. Left side of the inferior vena cava

D. Left renal vein

Answer: D

The right spermatic vein drains directly into the inferior vena cava. On the left, the spermatic vein drains into the left renal vein. (See Schwartz 9th ed., p 1461.)

CLINICAL QUESTIONS

1. Patients with bladder stones are at increased risk for which of the following bladder cancers?

A. Adenocarcinoma

B. Transitional cell carcinoma

C. Squamous cell carcinoma

D. Choriocarcinoma

Answer: C

The most common form of bladder cancer in the United States is transitional cell carcinoma (TCC). Tobacco use, followed by occupational exposure to various carcinogenic materials such as automobile exhaust or industrial solvents are the most frequent risk factors, though many with the disease have no identifiable risks. Other forms of bladder cancer, such as adenocarcinoma and squamous cell carcinoma, occur in distinct patient populations. Patients with chronic irritation from catheters, bladder stones, or schistosomiasis infection are at risk for the squamous cell variant while those with urachal remnants or bladder exstrophy have an increased risk of adenocarcinoma. (See Schwartz 9th ed., p 1461.)

2. Emphysematous pyelonephritis is most commonly caused by

A. Clostridia perfringens

B. Escherichia coli

C. Group A Streptococcus

D. Bacteroides species

Answer: B

Emphysematous pyelonephritis is a life-threatening infection that results from complicated pyelonephritis by gas-producing organisms. It is an acute necrotizing infection of the kidney that occurs predominantly in diabetic patients. Patients frequently present with sepsis and ketoacidosis. Escherichia coli appears to be the most frequent organism responsible for this infection. Patients require supportive care, IV antibiotics, and relief of any urinary tract obstruction. Emphysematous pyelonephritis can be subdivided based on extent of infection. Those with gas confined to the parenchyma frequently can be managed conservatively with placement of a nephrostomy tube to allow drainage of purulent material. Patients with extensive involvement of the perirenal tissue may not respond to conservative management, and strong consideration should be given to expeditious nephrectomy, particularly if the patient is displaying signs of sepsis. (See Schwartz 9th ed., p 1470.)

3. Expectant management may be considered for men with prostate cancer who

A. Have a Gleason score >10

B. Are 55 years of age

C. Have low volume disease as determined by biopsy

D. Have a PSA level 35

Answer: C

Expectant management may be a useful strategy in men with anticipated survival of 10 years, low Gleason score (≤6), early-stage disease (cT1c), and small volume disease as determined by biopsy. Patients should be watched closely with digital rectal exam, PSA testing, and repeat biopsy at 1 year to assess the possible progression of disease.

Prostate cancer is graded according to the Gleason scoring system. A primary and secondary score are assigned based on the most common and second most common histologic pattern. Grades run from 1 for the most differentiated to 5 for the least. The grades are added to give the Gleason score. In current practice, scores below 6 are almost never assigned. Gleason score, pre-operative PSA level, and digital rectal exam are used to estimate the likelihood of whether the cancer is localized, locally advanced, or metastatic. Prostate cancer with high Gleason scores (8 to 10) or a high PSA level (>20) is much more likely to have spread, often at a micrometastatic level. (See Schwartz 9th ed., p 1465.)

4. A blunt injury to the kidney with a 2-cm, nonexpanding hematoma and a small amount of urinary extravasation is

A. A grade 1 injury

B. A grade 2 injury

C. A grade 3 injury

D. A grade 4 injury

Answer: D

Any injury that involves the collecting system (implied by the urinary leak) is a grade 4 injury. The AAST grading system is shown in Table 40-1. (See Schwartz 9th ed., p 1466.)

TABLE 40-1 American Association for the Surgery of Trauma renal injury scale

Image

5. Injuries to the distal ureter should be treated with

A. Primary repair

B. End-to-end anastomosis after spatulation

C. Uretero-ureterostomy (to the contralateral ureter)

D. Ureteral reimplantation

Answer: D

Surgical repair depends on location and extent of injury. A suture in place briefly may be removed usually without consequence. Partial injuries can be primarily repaired, although all devitalized tissue must be débrided to avoid delayed tissue breakdown and urinoma formation. Ureteral stents should be placed in this situation to facilitate healing without stricture. Lower ureteral injuries (below the iliac vessels) are best treated with ureteral reimplant, as the blood supply can be tenuous, and strictures are more common with a distal uretero-ureterostomy. Midureteral level injuries can be treated with a uretero-ureterostomy if a spatulated, tension-free repair can be achieved. For longer defects, the bladder can be mobilized and brought up to the psoas muscle (psoas hitch). For additional length, a tubularized flap of bladder (Boari flap) can be created and anastomosed to the remaining ureter. Renal mobilization with nephropexy by anchoring to the psoas muscle can provide additional length. Autotransplantation, transureteroureterostomy, and ileal ureter are rarely needed during an acute setting. (See Schwartz 9th ed., p 1466.)

6. Elevated serum levels of alpha fetoprotein in a man with a firm testicular mass make which of the following diagnoses most likely?

A. Seminomatous germ cell tumor

B. Nonseminomatous germ cell tumor

C. Leydig cell tumor

D. Sertoli cell tumor

Answer: B

All solid testicular masses observed on physical examination and documented on ultrasound are malignant until proven otherwise, because the vast majority are cancerous. Initial studies must include tumor markers, including alpha-fetoprotein and beta human chorionic gonadotrophin. Elevated tumor markers are found almost exclusively in nonseminomatous germ cell tumor, though occasionally seminomas will cause a modest rise in beta human chorionic gonadotrophin.

Most testicular neoplasms arise from the germ cells, though nongerm cell tumors arise from Leydig’s or Sertoli’s cells. The nongerm cell tumors are rare and generally follow a more benign course. Germ cell cancers are categorically divided into seminomatous and nonseminomatous forms that follow different treatment algorithms. (See Schwartz 9th ed., p 1462.)

7. Which of the following types of renal calculi will NOT be seen on CT scan?

A. Calcium oxalate

B. Struvite (magnesium ammonium phosphate)

C. Uric acid

D. Crystalline excreted indinavir

Answer: D

Urolithiasis, or urinary calculus disease, may affect up to 10% of the population over the course of a lifetime. Calculi are crystalline aggregates of one or more components, most commonly calcium oxalate. They also may contain calcium phosphate, magnesium ammonium phosphate (struvite), uric acid, or cystine. Calcium and struvite-containing stones often are visible on plain radiographs, but CT scans will demonstrate all calculi except those composed of crystalline-excreted indinavir, an antiretroviral medication. (See Schwartz 9th ed., p 1472.)

8. A patient with renal cell carcinoma with extension into the IVC (tumor thrombus) is best treated with

A. Radiotherapy

B. Chemotherapy

C. Thrombolytic therapy

D. Surgery

Answer: D

Up to 10% of RCC invades the lumen of the renal vein or vena cava. The degree of venous extension directly impacts the surgical approach. Patients with thrombus below the level of the liver can be managed with cross-clamping above and below the thrombus and extraction from a cavotomy at the insertion of the renal vein (Fig. 40-1A). Usually, the thrombus is not adherent to the vessel wall. However, cross-clamping the vena cava above the hepatic veins can drastically reduce cardiac preload, and therefore, bypass techniques often are necessary. For thrombus above the hepatic veins, a multidisciplinary approach with either venovenous or cardiopulmonary bypass is necessary. In cases of invasion of the wall of the vena cava or atrium, deep hypothermic circulatory arrest may be used to give a completely bloodless field. Tumor thrombus embolization to the pulmonary artery is a rare but known complication during these cases and is associated with a high mortality (Fig. 40-1B). For cases of extensive tumor thrombus, intraoperative transesophageal echocardiography should be considered for monitoring and assessment of possible thrombus embolization. If a thrombus embolization occurs, a sternotomy/cardiopulmonary bypass with extraction of the thrombus may be life saving. (See Schwartz 9th ed., p 1464.)

Image

FIG. 40-1. Inferior vena cava thrombus. A. A multidetector computed tomographic image displaying a tumor thrombus extending above the diaphragm (arrow) arising from a right renal mass. B. An en bloc removal of a different right renal mass with a tumor thrombus that extended to the pulmonary artery. This patient is alive 6 years after surgery.

9. The most common noncontinent urinary diversion procedure after cystectomy is

A. Orthotopic neobladder (ileal pouch)

B. Ileal conduit

C. Appendiceal conduit

D. Ureterostomy

Answer: B

Patients have multiple reconstructive options, including continent and noncontinent urinary diversions following cystectomy. The orthotopic neobladder has emerged as a popular urinary diversion for patients without urethral involvement. This diversion type involves the detubularization of a segment of bowel, typically distal ileum, which is then refashioned into a pouch that is anastomosed to the proximal urethral. Detubularization decreases intrapouch filling pressure, which improves urinary storage capacity. The external sphincter is still intact, and voiding is achieved through sphincteric relaxation and a Valsalva’s maneuver. The most common noncontinent diversion is the ileal conduit, whereby a segment of distal ileum is isolated with one end brought out through the abdominal wall as a urostomy. Ileal conduits are preferred for renal insufficiency because urine is not ‘stored’ and therefore has less time in contact with the absorptive surface of the ileal segment. Conduits are also used when the bladder is unresectable, but urinary diversion is necessary due to intractable bleeding or severe voiding pain. Each segment of bowel that is used offers its own advantages and inherent complications. (See Schwartz 9th ed., p 1461.)

10. Initial management of a patient with priapism includes

A. Bed rest, narcotics, and hydration

B. Administration of beta blockers

C. Placement of an 18-g IV catheter into the corpus cavernosum

D. Surgical exploration

Answer: C

The management of priapism is rapid detumescence with the goal of preservation of future erectile function. The ability to achieve normal erections is directly related to length of the episode of priapism. Low-flow priapism can be confirmed with a penile blood gas of the cavernosal bodies demonstrating hypoxic, acidotic blood. Initial management can include oral agents such as pseudoephedrine or baclofen, but more aggressive measures usually are necessary to achieve rapid detumescence. Insertion of a large gauge needle (18 gauge) into the lateral aspect of one corporal body allows thorough aspiration and irrigation of both corporal bodies because of widely communicating channels. Injection of phenylephrine (up to 200 mg in 20 mL normal saline) into the corporal bodies may be required. For those with sickle cell disease, hydration and oxygen administration should be performed first, as that is sometimes successful in this group. (See Schwartz 9th ed., p 1470.)

11. A patient with a complex pelvic fracture is scheduled for open reduction and fixation of the fractures in the operating room. He also has an extraperitoneal bladder injury with a contained area of extravasation. The best treatment for the bladder injury is

A. Leaving a Foley catheter in place for 7-10 days

B. Percutaneous drainage of the extravasation and Foley catheter drainage of the bladder

C. Transurethral repair of the bladder injury

D. Open repair of the bladder injury

Answer: D

Extraperitoneal bladder injuries can typically be managed with catheter drainage for 7 to 10 days. If intraoperative exploration is to occur for other injuries, repair can be performed at that time. For patients with pelvic injuries that require an open operation with placement of metal hardware, repair of the bladder rupture should be performed if possible. Intraperitoneal bladder injuries should be explored immediately and repaired. However, for cases of a missed intraperitoneal injury, patients often do well with catheter drainage only. For large ruptures after repair, a suprapubic tube is recommended, but a large urethral catheter is sufficient for smaller injuries. All injuries, especially those managed nonoperatively, should be followed up by a cystogram to document healing before catheter removal. (See Schwartz 9th ed., p 1467.)

12. Paraphimosis refers to

A. Inability to retract the foreskin

B. Inability to reduce the foreskin after it has been retracted

C. Infection of the foreskin

D. Excessive length of foreskin

Answer: B

Paraphimosis is a common problem that represents a true medical emergency. When foreskin is retracted for prolonged periods, constriction of the glans penis may ensue. This is particularly likely in hospitalized patients who are confined to bed or who have altered mentation. Edema often forms in the genitals of supine patients due to the dependent position of that area. Patients with diminished consciousness will not be aware of the penile pain from paraphimosis, which may delay recognition of the problem until too late. Delay can be catastrophic as penile necrosis may occur due to ischemia. (See Schwartz 9th ed., p 1470.)

13. Which of the following is an absolute indication for surgical exploration of an injured kidney?

A. Grade V injury

B. Large urinoma from a collecting duct injury

C. Contained hematoma >5 cm in diameter

D. Renovascular hypertension

Answer: A

The absolute and relative indications for surgical exploration of an injured kidney are listed in Table 40-2. (See Schwartz 9th ed., p 1465, 66.)

TABLE 40-2 Indications for surgical intervention for renal trauma


Absolute indications

1. Persistent, life-threatening hemorrhage from probable renal injury

2. Renal pedicle avulsion (grade V injury)

3. Expanding, pulsatile, or uncontained retroperitoneal hematoma Relative indications

1. Large laceration of the renal pelvis or avulsion of the ureteropelvic junction

2. Coexisting bowel or pancreatic injuries

3. Persistent urinary leakage, postinjury urinoma, or perinephric abscess with failed percutaneous or endoscopic management

4. Abnormal intraoperative one-shot IV urogram

5. Devitalized parenchymal segment with associated urine leak

6. Complete renal artery thrombosis of both kidneys or of a solitary kidney when renal perfusion appears preserved

7. Renal vascular injuries after failed angiographic management

8. Renovascular hypertension


Source: Adapted with permission from Santucci RA, Wessells H, Bartsch G, et al: Evaluation and management of renal injuries: Consensus statement of the renal trauma subcommittee. BJU Int 93:937, 2004.

14. A patient with a complete anterior urethral injury after a high speed motor vehicle accident is best initially managed by

A. Placement of a Foley catheter for 8-10 days

B. Placement of a Foley catheter for 1 month

C. Placement of a suprapubic catheter

D. Immediate repair

Answer: C

Blunt anterior urethral injury can be managed in multiple ways and only small series are available in the literature to compare methods. Immediate surgical repair is not recommended in the acute setting with the exception of low velocity penetrating injuries. If the patient is stable with minimal hematoma formation, repair should be considered. In this setting of a 1- to 2-cm defect, the urethra can be débrided, spatulated, and anastomosed in an end-to-end, watertight fashion. Large defects should have treatment deferred, as grafts or flaps may be required for repair and the success may diminish with infections. For most cases, catheter drainage is recommended. Many advocate avoiding a placement of a urethral catheter, as it may convert a partial tear to a complete dissection. However, a single gentle passage performed by a urologist is safe. For a complete disruption, the placement of a suprapubic tube is recommended; however, a stricture at the site of injury may ensue. (See Schwartz 9th ed., p 1467.)

15. Following documentation of a firm mass in the testes by ultrasound in a 32-year-old male, tissue should be obtained for diagnosis by

A. Fine-needle aspiration

B. Core-needle biopsy

C. Open biopsy

D. Orchiectomy

Answer: D

There is no role for percutaneous biopsy of testicular masses due to the risk of seeding the scrotal wall and changing the natural retroperitoneal lymphatic drainage of the testicle, because the testes have a remarkably predictable pattern of lymphatic drainage. In cases where metastatic disease to the testicle is suspected, an open testicular biopsy by delivery of the testicle through the inguinal canal is recommended. Lymphoma may involve one or both testes, but evidence of the disease usually is present elsewhere in the body, although relapses may be isolated to the testes. (See Schwartz 9th ed., p 1462.)

16. Following transurethral resection of a superficial (noninvasive) transitional cell carcinoma, which of the following is instilled in the bladder to decrease the risk of recurrence?

A. Cyclophosphamide

B. Cis-platinum

C. Methotrexate

D. BCG (bacille Calmette-Guérin)

Answer: D

Patients with nonmuscle invasive TCC (confined to the bladder mucosa or submucosa) can be managed with transurethral resection alone. However, patients are at risk for recurrence and progression to muscle-invasive disease. Tumor grade is extremely important in assessing the risk of disease progression. Those patients with high-grade disease or recurrent tumors can be treated with intravesical agents such as bacille Calmette-Guérin or mitomycin C. These agents decrease risk of progression and recurrence, by induction of an effective immunologic antitumor response in the case of bacilli Calmette-Guérin and through direct cytotoxicity for mitomycin C. (See Schwartz 9th ed., p 1461.)

Adriamycin is actually used on occasion to prevent recurrences, whereasile cyclophosphamide is never used.

17. Which one of the following syndromes is associated with an increased risk of renal cell carcinoma?

A. Down syndrome

B. Von Hippel-Lindau syndrome

C. Neurofibromatosis type 1

D. Osteogenesis imperfecta

Answer: B

Most cases of RCC are sporadic, but many hereditary forms have been described. These syndromes frequently involve a germline mutation in a tumor-suppressor gene. Von Hippel-Lindau disease is associated with multiple tumors including clear-cell RCC. The involved gene, vhl, also frequently is mutated or hypermethylated in sporadic RCC. Other rare forms include Birt-Hogg-Dubé syndrome, where patients get oncocytomas or chromophobe tumors. Patients with hereditary papillary RCC and hereditary leiomyomatosis develop papillary RCC. (See Schwartz 9th ed., p 1463.)

18. Which of the following classes of medication is the most common initial treatment of men with symptomatic benign prostatic hypertrophy (BPH)?

A. Alpha agonist

B. Alpha blocker

C. Beta agonist

D. Beta blocker

Answer: B

Medical treatment of BPH is usually the first step. Alpha blockers act on alpha receptors in the smooth muscle of the prostate and decrease its tone. 5α-Reductase inhibitors, which block the conversion of testosterone to the more potent dihydrotestosterone, shrink the prostate over several months. (See Schwartz 9th ed., p 1471.)

‘Blockers’ and ‘antagonists’ are the same thing. ‘Agonists’ are is better becausesince they do exist but are not used for BPH.

19. In a patient with extensive Fournier’s gangrene involving the scrotum, the testes

A. Are usually involved and must be resected

B. Are usually involved but can be watched for 24-48 hours before deciding to perform an orchiectomy

C. Are usually not involved but should be removed due to the potential for post-operative pain

D. Are usually not involved and can be transposed to the soft tissue of the thigh

Answer: D

Prompt débridement of nonviable tissue and broad-spectrum antibiotics is necessary to prevent further spread [of infection in patients with Fournier’s gangrene] (Fig. 40-2A and B). If there is damage to the external sphincter, patients may require a colostomy. As the testes have a separate blood supply, they are usually not threatened and do not need to be removed. They may be tucked subcutaneously into the thigh (‘thigh pouch’) to ease postoperative management.

The testes are occasionally left exposed but wrapped in wet-to-dry dressings if there is a plan to do skin grafting in the immediate post-débridement time frame. They may be tucked subcutaneously into the thigh or left exposed wrapped in wet to dry dressings if early skin grafting is possible. (See Schwartz 9th ed., p 1469.)

Image

FIG. 40-2. Fournier’s gangrene. A. Necrotic scrotal skin from Fournier’s gangrene. B. Débridement of gangrenous tissue. Note the extensive débridement, which is commonly required. The right testicle required removal in this case (the left is wrapped in gauze), but typically the testes are not involved with the necrotic process.

20. Which of the following types of renal carcinoma has the worst prognosis?

A. Clear cell

B. Papillary

C. Chromophobe

D. Collecting duct

Answer: D

Various histologic subtypes of renal carcinoma include clear-cell, papillary (types I and II), chromophobe, collecting duct, and unclassified forms. Collecting duct and unclassified forms have dismal prognosis and very little response to systemic therapy. (See Schwartz 9th ed., p 1462.)