Chapter 32: Anesthesia for Genitourinary Surgery

Urological procedures range in impact from simple outpatient cystoscopy to surgical procedures with increased risk of perioperative complications, such as radical cystectomy and nephrectomy for renal cell carcinoma with vena caval thrombosis. Patients undergoing genitourinary procedures may be of any age, but many are elderly with coexisting medical illnesses, including kidney dysfunction. The impact of anesthesia on kidney function is discussed in Chapter 31. This chapter reviews the anesthetic management of common urological procedures. Use of lithotomy and steep head-down (Trendelenburg) positions complicates many of these procedures. Moreover, advances in preoperative patient optimization, perioperative management, and postoperative rehabilitation allow more patients with coexisting disease to be considered acceptable candidates for kidney transplantation, extensive tumor debulking operations, and reconstructive genitourinary procedures.

Preoperative Considerations

Cystoscopy is a very commonly performed urological procedure, and indications for this investigative or therapeutic operation include hematuria, recurrent urinary infections, renal calculi, and urinary obstruction. Bladder biopsies, retrograde pyelograms, transurethral resection of bladder tumors, extraction or laser lithotripsy of kidney stones, and placement or manipulation of ureteral catheters (stents) are also commonly performed through the cystoscope.

Anesthetic management varies with the age and gender of the patient and the purpose of the procedure. General anesthesia is usually necessary for children. Viscous lidocaine topical anesthesia with or without sedation provides satisfactory anesthesia for diagnostic cystoscopy in most women because of the short urethra. Men generally require regional or general anesthesia for diagnostic cystoscopy. Operative cystoscopies involving biopsies, cauterization, or manipulation of ureteral catheters require regional or general anesthesia, regardless of patient gender.

Intraoperative Considerations

A. Lithotomy Position

Next to the supine position, the lithotomy position is the most commonly used position for patients undergoing urological and gynecological procedures. Failure to properly position and pad the patient can result in pressure sores, nerve injuries, or compartment syndromes. Ideally, two people will move the patient’s legs simultaneously up into, or down from, the lithotomy position. Straps around the ankles or special holders support the legs in lithotomy position (Figure 32–1). The leg supports should be padded wherever there is leg or foot contact, and straps must not impede circulation. When the patient’s arms are tucked to the side, caution must be exercised to prevent the fingers from being caught between the mid and lower sections of the operating room table when the lower section is lowered and raised. Many clinicians will completely enclose the patient’s hands and fingers with protective padding to minimize this risk. Injury to the tibial (common peroneal) nerve, resulting in loss of dorsiflexion of the foot, may result if the lateral knee rests against the strap support. If the legs are allowed to rest on medially placed strap supports, compression of the saphenous nerve can result in numbness along the medial calf. Excessive flexion of the thigh against the groin can injure the obturator and, less commonly, the femoral nerves. Extreme flexion at the thigh can also stretch the sciatic nerve. The most common nerve injuries directly associated with the lithotomy position involve the lumbosacral plexus. Brachial plexus injuries can likewise occur if the upper extremities are inappropriately positioned (eg, hyperextension at the axilla). Compartment syndrome of the lower extremities with rhabdomyolysis has been reported with prolonged time in the lithotomy position, after which lower extremity nerve damage is also more likely.

The lithotomy position is associated with major physiological alterations. Functional residual capacity decreases, predisposing patients to atelectasis and hypoxia. This effect is amplified by steep Trendelenburg positioning (30–45°), which is commonly utilized in combination with the lithotomy position. Elevation of the legs drains blood into the central circulation acutely. Mean blood pressure and cardiac output may increase. Conversely, rapid lowering of the legs from the lithotomy or Trendelenburg position acutely decreases venous return and cardiac output and can result in hypotension. Vasodilation from either general or regional anesthesia potentiates the hypotension in this situation, and for this reason, blood pressure measurement should be taken immediately after the legs are lowered.

B. Choice of Anesthesia

1. General anesthesia

Any anesthetic technique suitable for outpatients may be utilized. Because of the short duration (15–20 min) and outpatient setting of most cystoscopies, general anesthesia is often chosen, commonly employing a laryngeal mask airway. Oxygen saturation should be closely monitored when obese or elderly patients, or those with marginal pulmonary reserve, are placed in the lithotomy or Trendelenburg position.

2. Regional anesthesia

Both epidural and spinal blockade provide satisfactory anesthesia for cystoscopy. However, when neuraxial regional anesthesia is chosen most anesthesiologists prefer spinal anesthesia because onset of satisfactory sensory blockade may require 15 to 20 min for epidural anesthesia compared with 5 min or less for spinal anesthesia. Studies fail to demonstrate that immediate elevation of the legs into lithotomy position following administration of hyperbaric spinal anesthesia either increases the dermatomal extent of anesthesia to a clinically significant degree or increases the likelihood of severe hypotension. A T10 sensory level block provides excellent anesthesia for all cystoscopic procedures.

Preoperative Considerations

Benign prostatic hyperplasia (BPH) frequently leads to bladder outlet obstruction in men older than 60 years. Although most patients are treated medically, some require surgical intervention. Transurethral resection of the prostate (TURP) may be performed for bladder outlet obstruction due to BPH. Indications for TURP include obstructive uropathy, bladder calculi, and recurrent episodes of urinary retention, urinary tract infections, and hematuria. Patients with prostate cancer who are not candidates for radical prostatectomy may also benefit from TURP to relieve urinary obstruction.

TURP requires regional or general anesthesia. Despite advanced age and prevalence of significant comorbidity, perioperative mortality and medical morbidity (most frequently myocardial infarction, pulmonary edema, and kidney failure) for this procedure are both less than 1%.

The most common surgical complications of TURP are clot retention, failure to void, uncontrolled hematuria requiring surgical revision, urinary tract infection, and chronic hematuria, although other complications may include TURP syndrome, bladder perforation, sepsis, hypothermia, and disseminated intravascular coagulation (DIC). A blood type and screen (see Chapter 51) is adequate for most patients, although crossmatched blood should be available for anemic patients and for patients with a large prostate in which extensive resection is contemplated. Prostatic bleeding can be difficult to control through the cystoscope.

Intraoperative Considerations

TURP is conventionally performed by passing a monopolar electrical loop through a special cystoscope (resectoscope). Using continuous irrigation and direct visualization, prostatic tissue is resected by applying a cutting current to the loop. Because of the characteristics of the prostate and the large amounts of irrigation fluid often used, TURP can be associated with serious complications (Table 32–1).

A. TURP Syndrome

Transurethral prostatic resection, now a relatively uncommon procedure, often opens the extensive network of venous sinuses in the prostate, potentially allowing systemic absorption of the irrigating fluid. The absorption of large amounts of fluid (2 L or more) results in a constellation of symptoms and signs commonly referred to as TURP syndrome (Table 32–2). The manifestations are primarily those of circulatory fluid overload, water intoxication, and, occasionally, toxicity from the solute in the irrigating fluid. The incidence of TURP syndrome is less than 1%. This syndrome presents intraoperatively or postoperatively as headache, restlessness, confusion, cyanosis, dyspnea, arrhythmias, hypotension, seizures, or a combination of these, and it can be rapidly fatal. TURP syndrome is most commonly associated with large-volume prostate resection and use of large volumes of irrigation fluid, and has also been much less commonly reported with cystoscopy, arthroscopy, transurethral resection of bladder tumors, and transcervical resection of the endometrium.

Electrolyte solutions cannot be used for irrigation during monopolar TURP because they disperse the electrocautery current. Water provides excellent visibility because its hypotonicity lyses red blood cells, but significant water absorption can readily result in acute water intoxication. Water irrigation is generally restricted to transurethral resection of bladder tumors only. For monopolar TURP, slightly hypotonic nonelectrolyte irrigating solutions such as glycine 1.5% (230 mOsm/L) or a mixture of sorbitol 2.7% and mannitol 0.54% (195 mOsm/L) are most commonly used. Less commonly used solutions include sorbitol 3.3%, mannitol 3%, dextrose 2.5% to 4%, and urea 1%. Because all these fluids are still hypotonic, significant absorption of water can occur. Fluid absorption rate is also influenced by irrigation fluid pressure, and high pressures (high bottle or bag height) increases the rate of fluid absorption.

Absorption of TURP irrigation fluid is dependent on the duration of the resection and the pressure of the irrigation fluid. Pulmonary edema can readily result from the absorption of large amounts of irrigation fluid, particularly in patients with limited cardiac reserve. The hypotonicity of these fluids also results in acute hyponatremia and hypoosmolality, which can lead to serious neurological manifestations. Symptoms of hyponatremia usually do not develop until the serum sodium concentration decreases below 120 mEq/L. Marked hypotonicity in plasma ([Na⁺] <100 mEq/L) may also result in acute intravascular hemolysis.

Toxicity may also arise from absorption of the solutes in these fluids. Marked hyperglycinemia has been reported with glycine solutions and may contribute to circulatory depression and central nervous system toxicity. Glycine has been implicated in rare instances of transient blindness following TURP. Hyperammonemia, presumably from the degradation of glycine, has also been documented in a few patients with marked central nervous system toxicity following TURP.

Treatment of TURP syndrome depends on early recognition and should be based on the severity of the symptoms. The absorbed water must be eliminated, and hypoxemia and hypoperfusion treated. Most patients can be managed with fluid restriction and intravenous administration of furosemide. Symptomatic hyponatremia resulting in seizures or coma should be treated with hypertonic saline (see Chapter 49). Seizure activity can be terminated with small doses of midazolam (2–4 mg). Endotracheal intubation may be considered to prevent aspiration until the patient’s mental status normalizes. The amount and rate of hypertonic saline solution (3% or 5%) needed to correct the hyponatremia to a safe level should be based on the patient’s serum sodium concentration (see Chapter 49).

Recently, additional procedural methods for treatment of BPH have included bipolar TURP, laser and radiofrequency ablation, photodynamic and thermal therapy, and cryotherapy. Low-voltage bipolar TURP allows use of isotonic saline irrigation fluid, thus avoiding TURP syndrome with the exception of the persisting risk of fluid overload, and because the procedure simultaneously cauterizes as it resects, it decreases the risk of clot retention.

B. Hypothermia

Large volumes of irrigating fluids at room temperature can be a major source of heat loss in patients. Irrigating solutions should be warmed to body temperature prior to use to prevent hypothermia. Postoperative shivering associated with hypothermia may dislodge clots and promote postoperative bleeding.

C. Bladder Perforation

The incidence of bladder perforation during TURP is less than 1% and may result from either the resectoscope going through the bladder wall or from overdistention of the bladder with irrigation fluid. Most bladder perforations are extraperitoneal and are signaled by poor return of the irrigating fluid. Awake patients will typically complain of nausea, diaphoresis, and retropubic or lower abdominal pain. Large extraperitoneal, and most intraperitoneal, perforations are usually even more obvious, presenting as sudden unexplained hypotension or hypertension, and with generalized abdominal pain in awake patients. Regardless of the anesthetic technique employed, perforation should be suspected in settings of sudden hypotension or hypertension, particularly with acute, vagal-mediated bradycardia.

D. Coagulopathy

DIC following TURP may result from the release of thromboplastins from prostate tissue during the procedure. Rarely, patients with metastatic carcinoma of the prostate develop a coagulopathy from primary fibrinolysis due to secretion of a fibrinolytic enzyme. Coagulopathy may be suspected from diffuse, uncontrollable bleeding, but must be defined with laboratory tests. Primary fibrinolysis should be treated with ε-aminocaproic acid (Amicar) or tranexamic acid. Treatment of DIC in this setting may require heparin in addition to replacement of clotting factors and platelets, and consultation with a hematologist should be considered.

E. Septicemia

The prostate is often colonized with bacteria and may harbor chronic infection. Extensive surgical resection with the opening of venous sinuses can allow entry of organisms into the bloodstream. Bacteremia following transurethral surgery is common. Prophylactic antibiotic therapy (most commonly gentamicin, levofloxacin, or cefazolin) prior to TURP is often administered.

F. Choice of Anesthesia

Either spinal or epidural anesthesia with a T10 sensory level, or general anesthesia, provides excellent anesthesia and good operating conditions for TURP. When compared with general anesthesia, regional anesthesia may reduce the incidence of postoperative venous thrombosis. It is also less likely to mask symptoms and signs of TURP syndrome or bladder perforation. Clinical studies have failed to show any differences in blood loss, postoperative cognitive function, and mortality between regional and general anesthesia. Acute hyponatremia from TURP syndrome may delay or prevent emergence from general anesthesia.

G. Monitoring

Evaluation of mental status in the awake or moderately sedated patient is the best monitor for detection of early signs of TURP syndrome and bladder perforation. Blood loss is particularly difficult to assess during TURP because of the use of irrigating solutions, so it is necessary to rely on clinical signs of hypovolemia (see Chapter 51). Blood loss averages approximately 3 to 5 mL/min of resection (usually 200–300 mL total) but is rarely life-threatening. Transient, postoperative decreases in hematocrit may simply reflect hemodilution from absorption of irrigation fluid. Very few patients will require intraoperative blood transfusion.

The treatment of kidney stones has evolved from primarily open surgical procedures to less invasive or entirely noninvasive techniques. Cystoscopic procedures, including flexible ureteroscopy with stone extraction, stent placement, and intracorporeal lithotripsy (laser or electrohydraulic), along with medical expulsive therapy (MET), have become first-line therapy. Extracorporeal shock wave lithotripsy (ESWL) is also utilized, primarily for 4-mm to 2-cm intrarenal stones, and percutaneous and laparoscopic nephrolithotomy for larger or impacted stones. MET has become the treatment of choice among many clinicians for acute episodes of urolithiasis: for stones up to 10 mm in diameter, administration of the α-blockers tamsulosin (Flomax), doxazosin (Cardura), or terazosin (Hytrin) or the calcium channel blocker nifedipine (Procardia, Adalat) increases the likelihood of stone expulsion.

During ESWL, repetitive high-energy shocks (sound waves) are generated and focused on the stone, causing it to fragment. Water or (more commonly) a conducting gel couples the generator to the patient. The change in acoustic impedance at the tissue–stone interface creates shear and tear forces on the stone, fragmenting it sufficiently to allow its passage in small pieces down the urinary tract. Ureteral stents are often placed prior to the procedure. Contraindications to the procedure include the inability to position the patient so that lung and intestine are away from the sound wave focus, urinary obstruction below the stone, untreated infection, a bleeding diathesis, and pregnancy. The presence of a nearby aortic aneurysm or an orthopedic prosthetic device is a relative contraindication.

Electrohydraulic, electromagnetic, or piezoelectric shock wave generators may be used for ESWL. With older electrohydraulic units, the patient is placed in a hydraulic chair and immersed in a heated water bath, which conducts the shock waves to the patient. Modern lithotriptors generate shock waves either electromagnetically or from piezoelectric crystals. The generator is enclosed in a water-filled casing and comes in contact with the patient via a conducting gel on a plastic membrane (Figure 32–2). In the case of electromagnetic machines, the vibration of a metallic plate in front of an electromagnet produces the shock waves. With piezoelectric models, the waves are the result of changes in the external dimensions of ceramic crystals when electric current is applied.

Preoperative Considerations

Patients with a history of cardiac arrhythmias and those with a pacemaker or implantable cardioverter defibrillator (ICD) may be at greater risk for arrhythmias during ESWL. Synchronization of the shock waves with the electrocardiogram (ECG) R wave decreases the incidence of arrhythmias during ESWL. The shock waves are usually timed to be 20 ms after the R wave to correspond with the ventricular refractory period, although studies suggest that asynchronous delivery of shocks may be safe in patients without heart disease. Shock waves can damage the internal components of implanted cardiac devices. The manufacturer should be contacted as to the best method for managing the device (eg, reprogramming or applying a magnet).

Intraoperative Considerations

Anesthetic considerations for ureteroscopy, stone manipulation, and laser lithotripsy are similar to those for cystoscopic procedures. ESWL requires special considerations, particularly when older lithotriptors requiring the patient to be immersed in water are used.

A. Effects of Immersion During ESWL

Immersion into a heated water bath (36–37°C) initially results in vasodilation that can transiently lead to hypotension. Arterial blood pressure, however, subsequently rises as venous blood is redistributed centrally due to the hydrostatic pressure of water on the legs and abdomen. Systemic vascular resistance (SVR) rises and cardiac output may decrease. Moreover, the increase in intrathoracic blood volume reduces functional residual capacity and may predispose some patients to hypoxemia.

B. Choice of Anesthesia

Pain during lithotripsy is from dissipation of a small amount of energy as shock waves enter the body through the skin. The pain is therefore localized to the skin and is proportionate to the shock wave intensity. Older water bath lithotripsy units require 1000 to 2400 relatively high-intensity shock waves, which most patients cannot tolerate without either regional or general anesthesia. In contrast, newer lithotripsy units that are coupled directly to the skin utilize 2000 to 3000 lower-intensity shock waves that usually require only light sedation.

C. Regional Anesthesia

Continuous epidural anesthesia is commonly employed when ESWL utilizes older water bath lithotriptors. A T6 sensory level ensures adequate anesthesia, as renal innervation is derived from T10 to L2. When using the loss of resistance technique for placement of the epidural catheter, saline should be used instead of air during epidural catheter insertion as air in the epidural space can dissipate shock waves and may promote injury to neural tissue. Foam tape should not be used to secure the epidural catheter as this type of tape has been shown to dissipate the energy of the shock waves when it is in their path. Spinal anesthesia can also be used satisfactorily but offers less control over the sensory level and an uncertain duration of surgery; for this reason, epidural anesthesia is usually preferred.

Disadvantages of regional anesthesia or sedation include the inability to control diaphragmatic movement (excessive diaphragmatic excursion can move the stone out of the wave focus and may prolong the procedure) and bradycardia (this will prolong the procedure when shock waves are coupled to the ECG). Glycopyrrolate may be administered to accelerate the ESWL procedure.

D. General Anesthesia

General endotracheal anesthesia allows control of diaphragmatic excursion during lithotripsy using older water bath lithotriptors. The procedure is complicated by the inherent risks associated with placing a supine anesthetized patient in a chair, elevating and then lowering the chair into a water bath to shoulder depth, and then reversing the sequence at the end. A light general anesthetic technique in conjunction with a muscle relaxant is preferable. The muscle relaxant ensures patient immobility and control of diaphragmatic movement.

E. Monitored Anesthesia Care

Monitored anesthesia care with intravenous midazolam and fentanyl is usually adequate for modern low-energy lithotripsy. Deeper sedation may also be used.

F. Monitoring

Standard anesthesia monitoring must be used for conscious or deep sedation, or for general anesthesia. Supraventricular arrhythmias may occur even with R wave synchronized shocks. With immersion lithotripsy, ECG pads should be attached securely with waterproof dressing. The temperature of the bath and the patient should be monitored to prevent hypothermia or hyperthermia.

G. Fluid Management

Intravenous fluid therapy is typically generous. Following an initial intravenous crystalloid fluid bolus, an additional 1000 to 2000 mL is often given with a small dose of furosemide to maintain brisk urinary flow and flush stone debris and blood clots. Patients with impaired cardiac reserve require more conservative fluid therapy.

Laparoscopic urological procedures, including partial and total nephrectomy, live donor nephrectomy, nephrolithectomy, and pyeloplasty are increasingly utilized because of advantages that include less perioperative pain, shorter hospital length of stay, and relatively rapid convalescence and return to function. Both transperitoneal and retroperitoneal approaches have been developed. A hand-assisted technique employs an additional larger incision that allows the surgeon to insert one hand for tactile sensation and facilitation of dissection. Anesthetic management is similar to that for any laparoscopic procedure.

Open procedures for kidney stones in the upper ureter and renal pelvis, and nephrectomies for nonmalignant disease, are often carried out in the “kidney rest” or lateral flexed position. With the patient in a full lateral position, the dependent leg is flexed and the other leg is extended. An axillary roll is placed beneath the dependent upper chest to minimize the risk of brachial plexus injury. The operating table is then extended to achieve maximal separation between the iliac crest and the costal margin on the operative side, and the kidney rest (a bar in the groove where the table bends) is elevated to raise the nondependent iliac crest higher and improve surgical exposure.

The lateral flexed position is associated with adverse respiratory and circulatory effects. Functional residual capacity is reduced in the dependent lung but may increase in the nondependent lung. In the anesthetized patient receiving controlled ventilation, ventilation/perfusion mismatching occurs because the dependent lung receives greater blood flow than the nondependent lung, whereas the nondependent lung receives greater ventilation, predisposing the patient to atelectasis in the dependent lung and to shunt-induced hypoxemia. The arterial to end-tidal gradient for carbon dioxide progressively increases during general anesthesia in this position, indicating that dead space ventilation also increases in the nondependent lung. Moreover, elevation of the kidney rest can significantly decrease cardiac output in some patients by compressing the inferior vena cava. Venous pooling in the legs potentiates anesthesia-induced vasodilation.

Because of the potential for large blood loss and limited access to major vascular structures in the lateral flexed position, initial placement of at least one large-bore intravenous catheter is advisable. Arterial catheters are often utilized. Endotracheal tube placement may be altered during positioning; thus proper endotracheal tube placement must again be verified following final patient positioning prior to skin preparation and surgical draping. Intraoperative pneumothorax may occur as a result of surgical entry into the pleural space.

Improved survival rates for patients with urological cancer following radical surgical resections have resulted in an increase in the number of procedures performed for prostatic, bladder, testicular, and renal cancer. The desire for accelerated, less-complicated recovery with smaller, less painful incisions has prompted development of laparoscopic pelvic and abdominal operations, including radical prostatectomy, cystectomy, pelvic lymph node dissection, nephrectomy, and adrenalectomy. Robotic-assisted technology has increasingly been applied to these procedures over the past decade.

Many urological procedures are carried out with the patient in a hyperextended supine position to facilitate exposure of the pelvis during pelvic lymph node dissection, retropubic prostatectomy, or cystectomy (Figure 32–3). The patient is positioned supine with the iliac crest over the break in the operating table, and the table is extended such that the distance between the iliac crest and the costal margin increases maximally. Care must be taken to avoid putting excessive strain on the patient’s back. The operating room table is also tilted head-down to make the operative field horizontal. In the frog-leg position, a variation of the hyperextended supine position, the knees are also flexed and the hips are abducted and externally rotated.

1. Prostate Cancer

Preoperative Considerations

Adenocarcinoma of the prostate is the most common nonskin cancer in men and is second only to lung cancer as the most common cause of cancer deaths in men older than 55 years. Approximately one in six men will be diagnosed with prostate cancer in their lifetime. Management varies from surveillance to radical surgery. Important variables include the grade and stage of the malignancy, the patient’s age, the concentration of prostate-specific antigen (PSA), and the presence of medical comorbidity. Transrectal ultrasound is used to guide transrectal biopsies. Clinical staging is based on the Gleason score of the biopsy specimens, magnetic resonance imaging (MRI) to determine whether there is tumor migration to regional lymph nodes, and bone scan.

Intraoperative Considerations

Patients with prostate cancer may present to the operating room for open radical retropubic prostatectomy with lymph node dissection, robot-assisted laparoscopic prostatectomy with pelvic lymph node dissection, salvage prostatectomy (following failure of radiation therapy), cryoablation, or bilateral orchiectomy for hormonal therapy.

A. Radical Retropubic Prostatectomy

Radical retropubic prostatectomy is usually performed with pelvic lymph node dissection through a lower midline abdominal incision. It may be curative for localized prostate cancer or occasionally used as a salvage procedure after failure of radiation. The prostate is removed en bloc with the seminal vesicles, ejaculatory ducts, and part of the bladder neck. A “nerve-sparing” technique may be used to help preserve sexual function. Following prostatectomy, the remaining bladder neck is anastomosed directly to the urethra over an indwelling urinary catheter. The surgeon may ask for intravenous administration of indigo carmine for visualization of the ureters, and this dye can be associated with hypertension or hypotension.

Radical retropubic (open) prostatectomy may be accompanied by significant operative blood loss. Most centers use direct arterial blood pressure monitoring, and central venous pressure monitoring may also be employed. Other centers routinely utilize noninvasive cardiac output monitoring (eg, LiDCOrapid or FloTrac/Vigileo). Operative blood loss varies considerably from center to center, with mean values less than 500 mL common. Factors influencing blood loss include prostate size, duration of operation, and the skill and experience of the surgeon. Blood loss and operative morbidity and mortality are similar in patients receiving general anesthesia and those receiving regional anesthesia. Neuraxial anesthesia requires a T6 sensory level, but these patients typically do not tolerate regional anesthesia without deep sedation because of the hyperextended supine position. The combination of a prolonged Trendelenburg position together with administration of large amounts of intravenous fluids may rarely produce edema of the upper airway. The risk of hypothermia should be minimized by utilizing a forced-air warming blanket and an intravenous fluid warmer.

Postoperative complications include hemorrhage, deep venous thrombosis (perhaps with pulmonary embolus), injuries to the obturator nerve, ureter, and rectum, and urinary incontinence and impotence. Extensive surgical dissection around the pelvic veins increases the risk of intraoperative venous air embolism and postoperative thromboembolic complications. An enhanced recovery approach to perioperative care should be standard. Although epidural anesthesia may reduce the incidence of postoperative deep venous thrombosis following open prostatectomy, this beneficial effect may be negated by the routine use of warfarin or fractionated heparin prophylaxis postoperatively, and in the era of enhanced recovery is less often used. Ketorolac and acetaminophen can be used as analgesic adjuvants and have been reported to decrease opioid requirements, improve analgesia, and promote earlier return of bowel function.

B. Robot-Assisted Laparoscopic Radical Prostatectomy

Robot-assisted laparoscopic radical prostatectomy with pelvic lymph node dissection differs from most other laparoscopic procedures by the frequent use of steep (>30°) Trendelenburg position for surgical exposure. Patient positioning, duration of procedure, need for abdominal distention, and desirability of increasing minute ventilation require use of general endotracheal anesthesia. Nitrous oxide is usually avoided to prevent bowel distention. Most laparoscopic prostatectomies are performed with robotic assistance, and the majority of radical prostatectomies in the United States are now performed via robot-assisted laparoscopy. When compared with open retropubic prostatectomy, laparoscopic robot-assisted prostatectomy is associated with a longer procedure time but with less blood loss and fewer blood transfusions, lower postoperative pain scores and lower opioid requirements, less postoperative nausea and vomiting, and shorter hospital length of stay. The steep Trendelenburg position can lead to head and neck tissue edema and to increased intraocular pressure. Complications reported to be associated with such positioning include upper airway edema and postextubation respiratory distress, postoperative visual loss involving ischemic optic neuropathy or retinal detachment, and brachial plexus injury. The surgeon should be routinely advised as to the length of time during which steep Trendelenburg positioning is maintained, and some centers have abandoned the routine use of this positioning entirely.

Most clinicians use a single large-bore intravenous catheter. The risk of hypothermia should be minimized by utilizing a forced-air warming blanket and an intravenous fluid warmer. Adequate postoperative analgesia is provided by ketorolac or acetaminophen, or both, and supplemented as needed with opioids. Postoperative epidural analgesia is not warranted because of relatively low postoperative pain scores and because patients may be discharged 24 h after surgery.

C. Bilateral Orchiectomy

Bilateral orchiectomy may be performed for hormonal control of metastatic prostate cancer. The procedure is relatively short (20–45 min) and is performed through a single midline scrotal incision. Although bilateral orchiectomy can be performed with local or regional anesthesia, most patients and many clinicians prefer general anesthesia, usually administered via a laryngeal mask airway, or spinal anesthesia.

2. Bladder Cancer

Preoperative Considerations

Bladder cancer occurs at an average patient age of 65 years with a 3:1 male to female ratio. Transitional cell carcinoma of the bladder is second to prostate adenocarcinoma as the most common malignancy of the male genitourinary tract. The association of cigarette smoking with bladder carcinoma results in coexistent coronary artery and chronic obstructive pulmonary disease in many of these patients. Underlying kidney impairment, when present, may be age related or secondary to urinary tract obstruction. Staging includes cystoscopy and computed tomography (CT) or MRI scans. Intravesical chemotherapy is used for superficial tumors, and transurethral resection of bladder tumors (TURBT) is carried out via cystoscopy for low-grade, noninvasive bladder tumors. Some patients may receive preoperative radiation to shrink the tumor before radical cystectomy. Urinary diversion is usually performed immediately following cystectomy.

Intraoperative Considerations

A. Transurethral Bladder Resection

Bladder tumors may occur at various sites within the bladder, and laterally located tumors may lie in proximity to the obturator nerve. In such cases, if spinal anesthesia is administered or if general anesthesia is administered without use of a muscle relaxant, use of the cautery resectoscope may result in stimulation of the obturator nerve and adduction of the legs. Urologists rarely derive amusement from having their ear struck by the patient’s knee; thus, in contrast to TURP, TURBT procedures are more commonly performed with general anesthesia and neuromuscular blockade. TURBT, unlike TURP, is rarely associated with absorption of significant amounts of irrigating solution.

B. Radical Cystectomy

With radical cystectomy, all anterior pelvic organs—including the bladder, prostate, and seminal vesicles—are removed in men; the bladder, uterus, cervix, ovaries, and part of the anterior vaginal vault may be removed in women. Pelvic node dissection and urinary diversion are also carried out. Radical cystectomy is associated with the greatest risk of perioperative morbidity and mortality of all major urological procedures, especially in the elderly patient population. However, continuous improvements in neoadjuvant chemotherapy and enhanced recovery after surgery programs have been associated with progressively lower rates of perioperative morbidity and mortality as well as higher rates of 1- and 5-year survival. When compared with open radical cystectomy, robot-assisted radical cystectomy is associated with reduced perioperative complications, less blood loss and transfusion, and shorter hospital length of stay.

Duration of radical cystectomy is typically 4 to 6 h and blood transfusion is frequently utilized. General endotracheal anesthesia with a muscle relaxant provides optimal operating conditions. Controlled hypotensive anesthesia may reduce intraoperative blood loss and transfusion requirements in open cystectomy, and some surgeons also believe it improves surgical visualization. However, maintenance of mean arterial pressure below 55 to 65 mm Hg may be associated with increased risk of acute kidney injury and stroke. Continuous epidural anesthesia can facilitate the induced hypotension, decrease general anesthetic requirements, and facilitate postoperative analgesia. Optimized intraoperative fluid administration (using noninvasive cardiac output monitoring) may decrease blood transfusion requirements, postoperative complications, and hospital length-of-stay. Continuous epidural infusion or transversus abdominis plane (TAP) block is frequently used for postoperative analgesia.

Many clinicians will place an arterial catheter along with two large-bore intravenous lines. Urinary output is correlated with the progress of the operation, as the urinary collection path is interrupted at an early point during most of these procedures. As with all lengthy operative procedures, the risk of hypothermia is minimized by use of a forced-air warming blanket and intravenous fluid warming.

C. Urinary Diversion

Urinary diversion (ie, implanting the ureters into a segment of bowel) is usually performed immediately following radical cystectomy. The selected bowel segment is either left in situ, such as in ureterosigmoidostomy, or divided with its mesenteric blood supply intact and attached to a cutaneous stoma or urethra. Moreover, the isolated bowel can either function as a conduit (eg, ileal conduit) or be reconstructed to form a continent reservoir (neobladder). Conduits may be formed from ileum, jejunum, or colon.

Major anesthetic goals for urinary diversion procedures include keeping the patient well hydrated and maintaining a brisk urinary output once the ureters are opened. Neuraxial anesthesia often produces unopposed parasympathetic activity due to sympathetic blockade, which results in a contracted, hyperactive bowel that makes construction of a continent ileal reservoir technically difficult. Papaverine (100–150 mg as a slow intravenous infusion over 2–3 h), glycopyrrolate (1 mg), or glucagon (1 mg) may alleviate this problem.

Prolonged contact of urine with bowel mucosa (slow urine flow) may produce significant metabolic disturbances. Hyponatremia, hypochloremia, hyperkalemia, and metabolic acidosis can occur following construction of jejunal conduits. In contrast, colonic and ileal conduits may be associated with hyperchloremic metabolic acidosis. The use of temporary ureteral stents and maintenance of high urinary flow help alleviate this problem in the early postoperative period.

3. Testicular Cancer

Preoperative Considerations

Testicular tumors are classified as either seminomas or nonseminomas. The initial treatment for all tumors is radical (inguinal) orchiectomy, and subsequent management depends on tumor histology. Retroperitoneal lymph node dissection (RPLND) plays a major role in the staging and management of patients with nonseminomatous germ cell tumors. Low-stage disease is managed with RPLND or in some instances by surveillance. High-stage disease is usually treated with chemotherapy followed by RPLND.

In contrast to other tissue types, seminomas are very radiosensitive tumors that are primarily treated with retroperitoneal radiotherapy. Chemotherapy is used for patients who relapse after radiation. Patients with large bulky seminomas or those with increased α-fetoprotein levels (usually associated with nonseminomas) are treated primarily with chemotherapy. Chemotherapeutic agents commonly include cisplatin, vincristine, vinblastine, cyclophosphamide, dactinomycin, bleomycin, and etoposide. RPLND is usually undertaken for patients with residual tumor after chemotherapy.

Patients undergoing RPLND for testicular cancer are typically young (15–35 years old) but are at increased risk for morbidity from the residual effects of preoperative chemotherapy and radiation therapy. In addition to bone marrow suppression, specific organ toxicity may be encountered, such as impaired kidney function following cisplatin, pulmonary fibrosis following bleomycin, and neuropathy following vincristine.

Intraoperative Considerations

A. Radical Orchiectomy

Inguinal orchiectomy can be carried out with regional or general anesthesia. Anesthetic management may be complicated by reflex bradycardia from traction on the spermatic cord.

B. Retroperitoneal Lymph Node Dissection

The retroperitoneum is usually accessed through a midline incision, but regardless of the surgical approach, all lymphatic tissue between the ureters from the renal vessels to the iliac bifurcation is removed. With the standard RPLND, all sympathetic fibers are disrupted, resulting in loss of normal ejaculation and infertility. A modified technique that may help preserve fertility limits the dissection below the inferior mesenteric artery to include lymphatic tissue only on the ipsilateral side of the testicular tumor.

Patients receiving bleomycin preoperatively may be particularly at risk for oxygen toxicity and fluid overload. Excessive intravenous fluid administration may promote pulmonary insufficiency or acute respiratory distress syndrome postoperatively and should be avoided. Anesthetic management should include use of the lowest inspired concentration of oxygen compatible with oxygen saturation above 90%. Positive end-expiratory pressure (5–10 cm H₂O) may help optimize oxygenation.

Evaporative and redistributive fluid losses with open RPLND can be considerable as a result of the large wound and the extensive surgical dissection. Retraction of the inferior vena cava during surgery often results in transient arterial hypotension.

Postoperative pain associated with open RPLND incisions is severe, and continuous epidural analgesia, intrathecal morphine or hydromorphone, or TAP block should be considered. Because ligation of intercostal arteries during left-sided dissections has rarely resulted in paraplegia, it may be prudent to document normal motor function postoperatively prior to institution of epidural analgesia. The arteria radicularis magna (artery of Adamkiewicz), which is supplied by these vessels and is responsible for most of the arterial blood to the lower half of the spinal cord, arises on the left side in most individuals. It should be noted that unilateral sympathectomy following modified RPLND usually results in the ipsilateral leg being warmer than the contralateral one. Patients who have undergone RPLND frequently complain of severe bladder spasm pain in the postanesthesia care unit.

4. Kidney Cancer

Preoperative Considerations

Renal cell carcinoma is the cause of approximately 3% of all adult cancers and 95% of all kidney cancers. It has a peak incidence between the fifth and sixth decades of life, with 2:1 male to female ratio. It is commonly discovered as an incidental finding in the course of evaluating a supposedly unrelated medical problem, such as in an MRI performed for evaluation of low back pain. The classic triad of hematuria, flank pain, and palpable mass occurs in only 10% of patients, and the tumor often causes symptoms only after it has grown considerably in size. Renal cell carcinoma is frequently associated with paraneoplastic syndromes, such as erythrocytosis, hypercalcemia, hypertension, and nonmetastatic hepatic dysfunction. Tumors confined to the kidney may be treated by open or laparoscopic partial or total nephrectomy, or by percutaneous cryoablation or radiofrequency ablation. Palliative surgical treatment may involve more extensive tumor debulking. In approximately 5% to 10% of patients, the tumor extends into the renal vein and inferior vena cava as a thrombus (Figure 32–4), and in some cases approaches or enters the right atrium. Staging includes CT or MRI scans and an arteriogram. Preoperative arterial embolization may shrink the tumor mass and reduce operative blood loss.

Preoperative evaluation of the patient with renal carcinoma should focus on tumor staging, kidney function, the presence of coexisting systemic diseases, and anesthetic management needs dictated by the scope of anticipated surgical resection. Preexisting kidney function impairment depends upon tumor size in the affected kidney as well as coexisting systemic disorders such as hypertension, diabetes, and coronary artery disease. Smoking is a well-established risk factor for renal cell carcinoma, and these patients have a high incidence of underlying coronary artery and chronic obstructive lung disease. Although some patients present with erythrocytosis, the majority are anemic.

Intraoperative Considerations

A. Percutaneous Cryoablation or Radiofrequency Ablation

Relatively small kidney tumors without metastasis are commonly ablated by interventional radiologists using percutaneous cryoprobes or radiofrequency probes with ultrasonography or CT guidance. This may be performed on an outpatient or 23-h stay basis. Routine American Society of Anesthesiologists (ASA) monitors are used, and general endotracheal anesthesia with muscle relaxation is usually employed to minimize the risk of patient movement during the procedure. An indwelling urinary catheter is typically used if the procedure duration is anticipated to be more than approximately 2 to 3 h. Precautions must be taken for patients with pacemakers or ICDs who are undergoing radiofrequency ablation (see Chapter 21). The patient is typically placed in the lateral decubitus or prone position. The patient may experience significant postoperative pain of limited duration requiring intravenous analgesia.

B. Radical Nephrectomy

The operation may be carried out via an anterior subcostal, flank, or (rarely) midline incision. Hand-assisted laparoscopic technique is often utilized for partial or total nephrectomy associated with a smaller tumor mass. Many centers prefer a thoracoabdominal approach for large tumors, particularly when a tumor thrombus is present. The kidney, adrenal gland, and perinephric fat are removed en bloc with the surrounding (Gerota) fascia. General endotracheal anesthesia is used, often in combination with epidural anesthesia.

This operation has the potential for extensive blood loss because these tumors are very vascular and often very large. Two large-bore intravenous lines with an indwelling peripheral arterial catheter are typically used. Transesophageal echocardiography (TEE), esophageal Doppler, or peripheral pulse wave analysis (Lidco or Vigileo) are often used for hemodynamic monitoring. TEE should be used for all patients with vena cava thrombus. Retraction of the inferior vena cava may be associated with transient arterial hypotension. Only brief periods of controlled hypotension should be used to reduce blood loss because of the potential for acute kidney injury in the contralateral kidney. Reflex vasoconstriction in the unaffected kidney can also result in postoperative kidney dysfunction.

If combined general–epidural anesthesia is employed, administration of epidural local anesthetic may be postponed until the risk of significant operative blood loss has passed. As with all lengthy operative procedures, the risk of hypothermia should be minimized by utilizing core temperature monitoring, a forced-air warming blanket and intravenous fluid warming. The postoperative course of subcostal, flank, or midline incision for open nephrectomy is extremely painful, and epidural analgesia is very useful in minimizing discomfort and accelerating convalescence.

C. Radical Nephrectomy with Excision of Tumor Thrombus

Because of the degree of physiological trespass and potential for major blood loss associated with this operation, the anesthetic management can be challenging. A thoracoabdominal approach allows the use of cardiopulmonary bypass when necessary.

Surgery can significantly prolong and improve quality of life, and in some patients, metastases may regress after resection of the primary tumor. A preoperative ventilation-perfusion scan may detect preexisting pulmonary embolization of the thrombus. Intraoperative TEE is helpful in determining whether the uppermost margin of the tumor thrombus extends to the diaphragm, above the diaphragm, into the right atrium, or even across the tricuspid valve. TEE can also be used to confirm the absence of tumor in the vena cava, right atrium, and right ventricle after successful surgery.

The presence of a large thrombus (level II, III, or IV) complicates anesthetic management. Problems associated with massive blood transfusion should be anticipated (see Chapter 51). Central venous catheterization should be performed cautiously to prevent dislodgement and embolization of tumor thrombus extending into the right atrium. An increased central venous pressure is typical with significant caval thrombus and reflects the degree of venous obstruction. Pulmonary artery catheters risk dislodgement of right atrial tumor thrombus, and provide no useful information that cannot be obtained from TEE.

Complete obstruction of the inferior vena cava markedly increases operative blood loss because of dilated venous collaterals. Patients are also at significant risk for potentially catastrophic intraoperative pulmonary embolization of the tumor. Tumor embolization may be heralded by sudden supraventricular arrhythmias, arterial desaturation, and profound systemic hypotension. TEE is critical in this situation. Cardiopulmonary bypass may be used when the tumor cannot be pulled back from the right atrium into the cava. Heparinization and hypothermia greatly increase surgical blood loss.

The success of renal transplantation, which is largely due to advances in immunosuppressive therapy, has greatly improved the quality of life for patients with end-stage kidney disease. With modern immunosuppressive regimens, cadaveric transplants have achieved almost the same 80% to 90% 3-year graft survival rate as living-related donor grafts.

Preoperative Considerations

Current organ preservation techniques allow ample time (24–48 h) for preoperative dialysis of cadaveric kidney recipients. Living-related transplants are performed electively with simultaneous donor and recipient operations. The recipient’s serum potassium concentration should be below 5.5 mEq/L, and existing coagulopathies should be corrected.

Intraoperative Considerations

Kidney transplantation is carried out by placing the donor kidney retroperitoneally in the iliac fossa and anastomosing the renal vessels to the iliac vessels and the ureter to the bladder. Heparin is administered prior to temporary clamping of the iliac vessels. Intravenous mannitol administered to the recipient helps establish an osmotic diuresis following reperfusion. Immunosuppression is initiated on the day of surgery with a combination of medications that may include corticosteroids, cyclosporine or tacrolimus, azathioprine or mycophenolate mofetil, antithymocyte globulin, monoclonal antibodies directed against specific subsets of T lymphocytes (OKT3), and interleukin-2 receptor antibodies (daclizumab or basiliximab). The anesthesia provider should discuss in advance with the surgery team the timing and dosage of any immunosuppressive agents that will need to be given perioperatively. Recipient nephrectomy for a failed transplant may be performed for intractable hypertension or chronic infection.

A. Choice of Anesthesia

Most kidney transplants are performed with general anesthesia, although spinal and epidural anesthesia are also utilized. All general anesthetic agents have been employed without any apparent detrimental effect on graft function. Cisatracurium may be the muscle relaxant of choice, as it is not dependent upon renal excretion for elimination. With careful neuromuscular monitoring other relaxants can be used safely.

B. Monitoring

A urinary catheter is placed preoperatively in addition to routine monitors, and brisk urine flow following the arterial anastomosis generally indicates good graft function. If the graft ischemic time was prolonged, an oliguric phase may precede the diuretic phase, in which case intravenous fluid therapy must be appropriately adjusted. Administration of furosemide or additional mannitol may be indicated in such cases. Hyperkalemia has been reported after release of the vascular clamp following completion of the arterial anastomosis, particularly in pediatric and other small patients, and release of potassium contained in the preservative solution has been implicated as the cause of this phenomenon. Donor kidney washout of the preservative solution with ice-cold lactated Ringer’s solution just prior to the vascular anastomosis may help avoid this problem. Serum electrolyte concentrations (particularly potassium) should be monitored closely after completion of the anastomosis. Hyperkalemia may be suspected from peaking of the T wave on the ECG.