SECTION III. Genitourinary System
A Cystectomy
1. Introduction
The bladder is usually removed for cancer but may also be removed for severe hemorrhagic or radiation cystitis. In a radical cystectomy for invasive cancer in women, the uterus, fallopian tubes, ovaries, and a portion of the vaginal wall are removed. In men, the ampulla of the vas deferens, prostate, and seminal vesicles are removed. There is also lymph node dissection, and a urinary diversion is created (through the intestine).
2. Preoperative assessment
a) Cardiac/respiratory/neurologic/endocrine: Assessment is routine.
b) Renal: Gross hematuria may be a symptom. Check renal function tests as well as evidence of a urinary tract infection.
c) Gastrointestinal: Patients are at risk for fluid and electrolyte imbalance because of bowel preparation.
3. Patient preparation
a) Laboratory tests: Complete blood count, electrolytes, blood urea nitrogen, creatinine, glucose, prothrombin time, partial thromboplastin time, type and screen for 2 to 4 units of blood, and urinalysis
b) Diagnostic tests: Electrocardiography and chest radiography for most of this patient population
c) Medication: Sedation as needed
4. Room preparation
a) Monitors: Standard, arterial line, and central venous pressure; urine output not measurable during this procedure; two large-bore, reliable intravenous lines available
b) Additional equipment: Epidural insertion and infusion supplies (if using), and warming devices for the patient and fluids
c) Position: Supine
d) Drugs and fluids: 6 to 10 mL/kg/hr of crystalloid for maintenance; 2 to 4 units of blood readily available
5. Perioperative management
Combined general/epidural or general anesthesia with standard induction is used. The patient may be anemic because of hematuria and hypovolemic because of bowel preparation. Attempt to correct these conditions before induction. Maintenance is routine, with special attention paid to fluid calculations and keeping the patient warm. Plan to extubate immediately postoperatively unless the patient is unstable during the procedure or when prior respiratory complications prevent early extubation.
6. Postoperative considerations
Epidural or patient-controlled analgesia should be planned for preoperative use. Watch the patient for signs of hypovolemia, anemia, or pulmonary edema resulting from fluid shifts intraoperatively.
B Cystoscopy
1. Introduction
Cystoscopy is the use of instrumentation to examine the urinary tract. A cystoscope may be used for diagnostic or therapeutic procedures such as the following: workup of hematuria, stricture, and tumor; removal and manipulation of stones; placement of stents; and follow-up of therapy. Retrograde pyelography and other dye studies may be used. This procedure is usually performed on an outpatient basis.
2. Preoperative assessment and patient preparation
a) History and physical examination: Standard
b) Diagnostic tests: Standard
c) Preoperative medication and intravenous therapy
(1) Prophylactic antibiotics
(2) 18-gauge intravenous catheter with minimal fluid replacement
3. Room preparation
a) Monitoring equipment: Standard
b) Pharmacologic agents: Indigo carmine, methylene blue
c) Position: Lithotomy
4 Anesthetic technique
The technique of choice is regional blockade or general anesthesia.
a) Intravenous sedation: Midazolam (Versed), fentanyl, or propofol in sedation doses
b) Regional blockade: Analgesia to T9 required
c) General anesthesia: Administered by mask or oral endotracheal tube
5. Preoperative management
a) Induction: No specific indications
b) Maintenance
(1) Diagnostic dyes may be administered. Use indigo carmine dye (α-sympathomimetic effects) cautiously in patients with hypertension or cardiac ischemia. Methylene blue dye may cause hypertension. Oxygen saturation readings may be altered by dye administration.
(2) Persistent erection may occur in younger male patients, thus preventing manipulation of the cystoscope. Use deeper anesthesia.
(3) Water or irrigation solution may be used to distend the bladder. See the discussion of transurethral resection of the prostate later in this section.
(4) Quadriplegic or paraplegic patients may undergo repeated cystoscopies. Autonomic hyperreflexia is possible if the injury is above level T5.
c) Emergence: No specific indications
6. Postoperative considerations
Postoperative care is standard.
C Extracorporeal Shock Wave Lithotripsy
1. Introduction
Extracorporeal shock-wave lithotripsy (ESWL) is a technique that uses high-energy shock waves to fragment renal calculi into small particles. A biplanar fluoroscopy unit is used to focus the shock wave on the target stone. The shock wave is repeated several thousand times and causes the stone to disintegrate. The focused, reflected shock wave passes through the water and enters the body through the flank. Immersion in water has significant physiologic effects on cardiovascular and respiratory function and on temperature regulation.
Immersion lithotripsy units require that the entire body except the head and neck be submerged. Changes in the temperature of the water bath affect the patient’s temperature. Both general and epidural anesthesia are associated with vasodilation and loss of shivering. This loss encourages heat transfer between the patient and the water. Both hypothermia and hyperthermia have been reported. The temperature of the water bath should be maintained at 35° to 37° C and should be continuously monitored.
Newer second- and third-generation lithotriptors do not require the patient to be submerged in water. Although they do use water for the production of shock waves, a membrane over the shock-wave generator encapsulates the fluid. Transmission of shock waves to the patient is ensured by the use of coupling gel between the patient and the generator membrane.
2. Preoperative assessment and patient preparation
a) Routine preoperative assessment with laboratory tests based on any abnormalities found in the history and physical examination. Consider cardiac status; many hemodynamic changes are associated with this procedure.
b) Absolute contraindications are pregnancy, abnormal coagulation parameters, an active urinary tract infection, and a urinary tract obstruction distal to the stone that prevents passage of stone fragments.
c) Relative contraindications include aortic aneurysm, spinal tumors, orthopedic implants in the lumbar region, morbid obesity, the presence of an abdominally placed cardiac pacemaker, uncontrolled arrhythmias, and coagulation disorders.
d) Ureteral stent placement before ESWL may be used to move the stone upward in the ureter, where it is amenable to therapy.
e) Adequate intravenous hydration aids in the passage of stone fragments.
f) Prophylactic antibiotics may be given.
g) Electrocardiography, automated cuff measurement of blood pressure, and pulse oximetry are indispensable during lithotripsy.
h) The electrocardiograph must be of good quality because the R wave is used to trigger the shocks. Synchronization of the shock wave to the electrocardiograph has reduced the incidence of cardiac dysrhythmias but has not totally eliminated them. These dysrhythmias are attributed to mechanical stimulation of the heart. Supraventricular premature complexes and premature ventricular complexes are the most common dysrhythmias noted. Atropine or glycopyrrolate may be given to increase the heart rate and thus the shock-wave rate.
3. Anesthetic considerations
a) Patient movement
For lithotripsy to be most effective, the stone must remain at the focal point. Because patient movement and patterns of respiration can change kidney and stone position, movement must be minimized and ventilation carefully controlled. The number and intensity of shock waves can be reduced when stone movement is minimized.
b) Anesthetic techniques
Various anesthetic techniques have been employed for ESWL. General anesthesia is advantageous because of its rapid onset and control of patient movement. Other techniques include spinal or epidural anesthesia, patient-controlled analgesia (PCA), monitored anesthesia care, and topical anesthesia with eutectic local anesthetics. Continuous infusions of propofol, methohexital, ketamine, and alfentanil have been used alone or with midazolam for ESWL anesthesia.
Spinal anesthesia has the advantage of a rapid onset, and a pure opiate spinal using sufentanil is a common technique. Disadvantages include hypotension, spinal headache, and the inability to reinforce the block.
Although epidural anesthesia is associated with a slower onset, hypotension is less, and the block can be reinforced as needed. A dermatomal level of T6 or T4 must be achieved to ensure patient comfort.
c) Side effects associated with ESWL
(1) Hypothermia, hyperthermia
(2) Cardiac dysrhythmias
(3) Hemorrhagic blisters of skin
(4) Renal edema
(5) Renal hematoma
(6) Lung injury
(7) Flank pain
(8) Hypertension, hypotension
(9) Autonomic hyperreflexia
(10) Nausea, vomiting
D Renal Transplant
1. Transplantation procedure
Renal transplantation has been performed for nearly a century and is an accepted means of replacing kidney function in patients with end-stage renal disease who are on maintenance dialysis. In this procedure, the donor kidney is placed extraperitoneally in the recipient’s iliac fossa. The renal artery is anastomosed to the internal iliac artery, the renal vein to either the external or the common iliac vein, and the ureter to the bladder. The anesthesia provider plays a vital role in management of the viability of the transplanted kidney. Three interrelated variables affect surgical outcomes: management of the donor, preservation of the harvested organ, and perioperative care of the transplant recipient. Additionally, improved surgical and immunosuppressive techniques have contributed to better outcomes in terms of graft survival.
2. Harvested organ preservation
Ischemic time, beginning with the clamping of the donor’s renal vessels and ending with the vascular anastomosis in the recipient, is a crucial factor in graft preservation. When renal ischemic time is less than 30 minutes, diuresis begins quickly, but if it is 2 hours or longer, a variable period of oliguria or anuria may occur. The definition of renal ischemic times for warm and cold preservation techniques is noted in the following table.
3. Donor preparation
a) Choice of anesthesia for the living, related donor is not critical.
b) Adequate amounts of balanced salt solution should be administered to ensure a brisk diuresis from the donor kidney and to offset reduced venous return resulting from use of the flank position.
c) The greatest risk to the donor is hemorrhage.
d) Adequate intravenous access and blood must be available in the event that transfusion becomes necessary.
e) If the donor kidney is obtained from a brain-dead patient, preservation of graft function is the highest priority. The loss of sympathetic tone after brain death may produce mild hypotension despite adequate volume replacement. Many patients with irreversible cerebral dysfunction are hypovolemic and require vigorous fluid resuscitation.
f) If pharmacologic support of the cardiovascular system is necessary, a dopamine infusion at a rate of 1 to 3 mcg/kg/min is recommended. Renal vasoconstrictive properties of high-dose vasopressors reduce immediate allograft function and increase the risk of kidney damage. Maintenance of urinary output is paramount and may warrant the use of diuretics and a low-dose dopamine infusion.
4. Recipient preparation
a) Because cadaveric kidneys can be preserved for 36 to 48 hours with cold perfusion, time is sufficient for optimal preparation of the transplant recipient.
b) The recipient should be free of acute illness and infections because of the likelihood of their spread during immunosuppressive therapy.
c) Acute alterations in fluid and electrolyte balance should be corrected with dialysis carried out 24 hours before transplantation. Postdialysis laboratory values should be checked, and the serum potassium (K +) level should be below 5.5 mEq/L. Coagulation studies and acid-base status should be normal. Serum creatinine concentration should be below 10 mg/dL and BUN level below 60 mg/dL after dialysis.
d) Anesthetic considerations are summarized in the following box.
Anesthesia for Renal Transplantation
I. Preoperative assessment and preparation
A. Clinical evaluation
1. Evaluate status of coexisting diseases.
a. Diabetes mellitus
b. Hypertension
c. Cardiac disease
d. Hyperparathyroidism
e. Pericardial tamponade
2. Perform dialysis within 24 hr of transplantation; check weight.
3. Evaluate tolerance to chronic anemia.
B. Laboratory evaluation
1. Complete blood count with platelet count
2. Prothrombin time, partial thromboplastin time, bleeding time
3. Blood urea nitrogen, creatinine, calcium, fluid balance
4. Electrocardiography; chest radiography
C. Type and cross-match 2 U of washed packed red blood cells
D. Determine current drug regimen
E. Premedication
1. Benzodiazepines, narcotics
2. Antacids, histamine-2 antagonists, metoclopramide
II. Monitors
A. Electrocardiography
B. Indirect or direct blood pressure measurement
C. Precordial, esophageal stethoscopy
D. Neuromuscular blockade evaluation
E. Foley catheter
F. Central venous, pulmonary capillary wedge pressure measurement, if required
III. Anesthetic management
A. Regional techniques
1. Continuous spinal or epidural
2. Advantages
a. No need for muscle relaxants
b. Potential respiratory tract infection from intubation is avoided
c. Amount of local anesthetic required is small
d. Patients are awake and comfortable postoperatively
3. Disadvantages
a. Patient anxiety
b. Uncomfortable surgical positions, especially for donor
c. Coagulation abnormalities present
d. Fluid management with sympathetic blockade is a challenge
e. Unprotected airway in patients with delayed gastric emptying
B. General anesthesia
1. Induction with thiopentapropofol or etomidate
2. Maintenance with volatile anesthetic (isoflurane or desflurane) or narcoticbased technique
3. Neuromuscular blockers
a. Succinylcholine
b. Atracurium and cis-atracurium
c. Vecuronium
IV. Miscellaneous drugs
A. Mannitol or furosemide
B. Prednisone or methylprednisolone
C. Azathioprine
D. OKT3
E. Cyclosporine
e) Chronic anemia is common, and transfusion is not required if oxygen delivery is adequate. Because of the danger of volume overload, anemia should be corrected during dialysis with transfusion of packed red blood cells.
f) Abnormal platelet function, as well as ineffective production of factor VIII and von Willebrand factor, accounts for the syndrome of uremic coagulopathy seen in patients with renal failure. Correction of coagulation abnormalities has been accomplished through dialysis and administration of conjugated estrogen and desmopressin.
g) Patients should fast for 6 to 8 hours if possible.
h) Premedication may include narcotics or benzodiazepines in usual to reduced doses, depending on the status of the patient.
i) The use of antacids, H 2 antagonists, and metoclopramide should be considered if gastric emptying is delayed; however, reduced doses should be considered, as these drugs depend on the kidney for excretion, and metoclopramide is partially excreted unchanged in the urine.
5. Monitoring considerations
a) In addition to routine monitors, a Foley catheter is inserted for the assessment of graft function.
b) Central venous pressure lines are not routinely inserted; their use may indirectly improve graft function by improving the assessment of hydration status.
c) A pulmonary artery catheter is useful if cardiac compromise is suspected or if the kidney is expected to have delayed graft function.
d) Protection of vascular access and fistula patency is of prime importance with the use of blood pressure cuffs or if arterial cannulation is necessary.
e) Sterile precautions during insertion of invasive lines are extremely important because transplant patients are immunocompromised.
f) Strict adherence to aseptic technique is mandatory in the management of these lines, catheters, and endotracheal tubes. Commitment to aseptic technique on the part of the entire team may make the difference between safe transplantation and death for the patient.
6. Fluid therapy
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