Prevalence and outcome of renal impairment at prostatectomy

Chronic kidney disease and perioperative outcomes in urological oncological surgery

OBJECTIVES

To evaluate baseline renal dysfunction among patients undergoing urological oncological surgery and its impact on early postoperative outcomes.

METHODS

Between 2005 and 2011, patients who underwent minimally-invasive or open radical prostatectomy, partial nephrectomy and radical nephrectomy, or open radical cystectomy, respectively, were identified in the National Surgical Quality Improvement Program dataset. Preoperative kidney function was assessed using estimated glomerular filtration rate and staged according to National Kidney Foundation definitions. Multivariable logistic regression was used to model the association between preoperative renal function and the risk of 30-day mortality and major complications. Furthermore the impact of chronic kidney disease on operation time and length of hospital stay was assessed.

RESULTS

Overall, 13,168 patients underwent radical prostatectomy (65.4%), partial nephrectomy (10.7%) and radical nephrectomy (16.1%) and radical cystectomy (7.8%), respectively; 50.1% of evaluable patients had reduced kidney function (chronic kidney disease II), and a further 12.6, 0.7 and 0.9% were respectively classified into chronic kidney disease stages III, IV, and V. Chronic kidney disease was an independent predictor of 30-day major postoperative complications (chronic kidney disease III: odds ratio 1.61, P < 0.001; chronic kidney disease IV: odds ratio 2.24, P = 0.01), of transfusions (chronic kidney disease III: odds ratio 2.14, P < 0001), of prolonged length of stay (chronic kidney disease III: odds ratio 2.61, P < 0.001; chronic kidney disease IV: odds ratio 3.37, P < 0.001; and chronic kidney disease V: odds ratio 1.68; P = 0.03) and of 30-day mortality (chronic kidney disease III: odds ratio 4.15, P = 0.01; chronic kidney disease IV: odds ratio 10.10, P = 0.003; and chronic kidney disease V: odds ratio 17.07, P < 0.001) compared with patients with no kidney disease.

CONCLUSIONS

Renal dysfunction might be underrecognized in patients undergoing urological cancer surgery. Chronic kidney disease stages III, IV and V are independent predictors for poor 30-day postoperative outcomes.

Natural History of Postobstructive Nephropathy: A Single-Center Retrospective Study

BACKGROUND

There is extensive published material on the effects of experimental ureteric obstruction. In contrast, there is very little literature on the natural history of postobstructive renal disease in patients.

METHODS

Patients presenting with obstructive nephropathy and renal impairment in a tertiary renal unit, and whose obstruction was successfully relieved, were identified, and the Modification of Diet in Renal Disease equation was used to calculate the glomerular filtration rate (GFR) at presentation and after relief of obstruction.

RESULTS

104 patients were identified (79 male). There were 9 deaths at 12 months and a further 4 deaths by 3 years; losses to follow-up were 7 and 20 at the same time points. The mean GFR was 9.2 +/- (SEM) 0.9 ml/min at presentation (n = 104), 27.8 +/- 1.7 ml/min at 3 months (n = 98), 29.0 +/- 1.8 ml/min at 12 months (n = 79), and 30.0 +/- 2.2 ml/min at 3 years (n = 61). Of 28 patients initially requiring dialysis, 6 were dialysis dependent at 3 months; 3 further patients, all with GFR <10 ml/min after relief of obstruction, required dialysis by 12 months and 1 further patient by 3 years.

CONCLUSIONS

Progressive deterioration in renal function is unusual after relief of obstruction in the majority of patients over a 3-year period. This relative stability in human postobstructive nephropathy contrasts with the course of remnant nephropathy in animal models.

The association between benign prostatic hyperplasia and chronic kidney disease in community-dwelling men

BACKGROUND

Benign prostatic hyperplasia (BPH) and chronic kidney disease are important public health problems in older men. Previous referral-based studies disagree on whether BPH is associated with chronic kidney disease. The objective of this study was to determine the community-based association between clinical measures of BPH and chronic kidney disease.

METHODS

A community-based sample of 2115 white men (ages 40-79 years) was randomly selected from the Olmsted County, Minnesota population (55% participation rate) in 1990. A random subsample (N= 476) had a detailed clinical evaluation. This evaluation included a questionnaire with similar queries to the International Prostate Symptom Score (IPSS), peak urinary flow rates (uroflowmeter), postvoid residual urine volume (ultrasound), prostate volume (ultrasound), serum prostate specific antigen (PSA), and serum creatinine.

RESULTS

After adjustment for age, hypertension, diabetes, leukocyte esterase positive (possible urinary tract infection), and smoking, chronic kidney disease [serum creatinine > or =133 micromol/L (1.5 mg/dL)] was associated with diminished peak urinary flow rate (<15 mL/sec) by an odds ratio (OR) = 2.96 (95% CI 1.30-7.01), moderate-severe lower urinary tract symptoms (IPSS >7) by an OR = 2.91 (95% CI 1.32-6.62), and chronic urinary retention (postvoid residual >100 mL) by an OR = 2.28 (95% CI 0.66-6.68). There was no association with a prostate volume >30 mL by an OR = 0.56 (95% CI 0.22-1.37) or PSA >1.4 ng/mL by an OR = 1.17 (95% CI 0.47-2.81).

CONCLUSION

There was a cross-sectional association between signs and symptoms of bladder outlet obstruction and chronic kidney disease in community-dwelling men. Prostatic enlargement was not associated with chronic kidney disease.

Is benign prostatic hyperplasia a risk factor for chronic renal failure?

PURPOSE

Benign prostatic hyperplasia (BPH) and chronic renal failure (CRF) are common medical conditions in older men. Based on the low prevalence of CRF in clinical trials recent American Urological Association guidelines have not recommended routine serum creatinine screening in men presenting with lower urinary tract symptoms. However, chronic renal failure is a well described complication of obstructive BPH.

MATERIALS AND METHODS

A structured MEDLINE review of the literature on the association between BPH and CRF from 1966 to 2003 was performed.

RESULTS

Most studies were referral based and did not represent the full spectrum of BPH in men. The definition of renal failure varied from a serum creatinine cutoff of 1.5 to 3.0 mg/dl. Differentiating acute and chronic renal failure, and acute and chronic urinary retention was often not done. Various combinations of chronic retention with large residual urine volumes (greater than 300 ml), detrusor instability and decreased bladder compliance were associated with chronic renal failure. Ureterovesicular junction obstruction from bladder remodeling in chronic urinary retention was the most commonly proposed mechanism for CRF. However, episodic acute urinary retention, urinary tract infections and secondary hypertension may also have a role. Studies showed significant improvement in renal function after prostate surgery but the acuity of renal failure was generally not known.

CONCLUSIONS

The extent of the association between BPH and CRF is unknown and more community based, observational studies are needed. However, an association exists and it should be considered in men presenting with obstructive BPH or CRF.