PREOPERATIVE RISK STRATIFICATION
Key Clinical Questions
How and when should postoperative urinary retention be further worked up?
When does hyponatremia associated with TUR syndrome need intervention?
How should postoperative hematuria be managed?
What is the approach to managing postoperative urine leak after prostatectomy or partial nephrectomy?
How should the postoperative management for adrenalectomy differ based on the type of adrenal tumor removed (pheochromocytoma, aldosteronoma, glucocorticoid-producing tumor)?
Any patient undergoing urology surgery should have a preoperative risk assessment. Obesity significantly contributes to the increased incidence and progression of urologic condition requiring surgery (eg, neoplasms, BPH, stress incontinence, erectile dysfunction, infertility, and urolithiasis); obese patients are also at increased risk for general postoperative complications. Increased peripheral androgen conversion to estrogen and secretion of prothrombin activator inhibitor-1 adipocytes contributes to a hypercoagulable state. Poor wound healing is more common in obese patients because of the proinflammatory state of the body, decreased peripheral perfusion, decreased local angiogenesis, and inhibited cell tissue response. The body habitus of obese patients also predisposes them to complications such as urethral-vesical anastomotic leak (UVAL) due to inadequate surgical exposure.
On the other end of the spectrum, poor preoperative nutritional status has also been well established as a risk factor for developing postoperative complications. Patients with one of four abnormalities in preoperative nutritional parameters have significantly higher-postoperative complication rates as well as longer hospital stays (low body mass index <24, preoperative weight loss >5%, arm muscle circumference <5th percentile, and low-serum albumin [below reference range]).
Risk factors that predispose patients to developing complicated UTIs include older age, external instrumentation, ureteral stent or other foreign body placement, metabolic dysfunction (obesity, diabetes mellitus, poor nutritional status), urinary tract obstruction (anatomic or functional), immunosuppression, and recent antibiotic use.
Patients with ureteral stents, indwelling catheters, and urinary ostomies have urine that is chronically colonized with bacteria. These patients should only be treated for a urinary tract infection if they have concomitant symptoms of a urinary tract infection.
Reflexive antibiotic administration in these patients leads to the development of resistant organisms.
Under normal physiologic conditions, the urgency to void is sensed when the bladder reaches a threshold of approximately 250 to 300 mL. Maximum bladder capacity for the average adult is 400 to 600 mL. Afferent pelvic sensory nerves are stimulated to transmit a signal to the parasympathetic ganglia in the spinal cord. Parasympathetic efferent fibers then fire a signal to the detrusor muscle of the bladder to initiate micturition when socially appropriate. Conversely, if micturition is not desired, afferent fibers will cause activation of the sympathetic nervous system and inhibit contraction of the detrusor muscle and cause contraction of the internal urethral sphincter (visceral efferent) and external sphincter (somatic efferent).
The incidence of postoperative urinary retention (POUR) ranges from 4% to 29%. Factors that contribute to POUR include prior history of ...