Postoperative resorptive and excretory capacity of the ileal neobladder

Abstract

OBJECTIVETo assess the extent and mechanism of renal reabsorption and excretion in patients with an ileal neobladder, as mild metabolic acidosis cause by proton reabsorption is common after such surgery, and long-term pharmacological correction is often necessary. PATIENTS AND METHODSThe study comprised 30 patients (29 men and one woman) with ileal neobladders after oncological surgery; before surgery all had normal retention values. Before and after withdrawing the transurethral catheter, serum creatinine and urea were analysed and used to assess the effect of the neobladder on retention values, expressed as the percentage change from baseline ( D creatinine and urea). RESULTSThere was a significant correlation between the D-creatinine and D-urea values ( P < 0.001; r = 0.66); 15 patients (50%) showed resorption of creatinine and urea, eight (27%) excreted creatinine into the neobladder and resorbed urea from it at the same time, and three (10%) showed the reverse response, i.e. creatinine resorption and urea excretion. Interestingly, four patients (13%) excreted both creatinine and urea into the neobladder. CONCLUSIONSWe assume that there was both a resorptive and excretory function. Probably the metabolic state (resorption or secretion) of the neobladder depends on its mucus production and on the internal surface, or on diuresis. Further investigation is required to characterize these different influences.

Eligibility for neoadjuvant/adjuvant cisplatin‐based chemotherapy among radical cystectomy patients

“…Third, we evaluated eligibility for cisplatin based on renal function alone and recognise the possibility that additional patients would have been considered ‘unfit’ for cisplatin based on Grade ≥2 hearing loss, peripheral neuropathy, or performance status. Fourth, the present observation that continent urinary diversion was independently associated with a negative change in GFR is quite possibly secondary to reabsorption properties of a neobladder or cutaneous pouch mimicking a calculated reduction in renal function given that catheter drainage was not routinely performed when evaluating GFR. Thus, for patients who would be candidates for adjuvant cisplatin‐based chemotherapy after a continent urinary diversion, accurate measurement of renal function with proper urinary drainage should be considered.…”

Comparative impact of continent and incontinent urinary diversion on long‐term renal function after radical cystectomy in patients with preoperative chronic kidney disease 2 and chronic kidney disease 3a

“…Indeed, both neobladder secretion and reabsorption of creatinine have been reported, and have been suggested to be dependent on the surface of the neobladder mucosa (i.e. mucus production) and on diuresis . Furthermore, we must acknowledge that, as our definition for recurrent urinary tract infection does include asymptomatic infections, the increased risk of this complication noted in our cohort of patients who received a continent diversion might be an artifact.…”

Impact of renal impairment on eligibility for adjuvant cisplatin‐based chemotherapy in patients with urothelial carcinoma of the bladder

“…32 Furthermore, estimations of renal function based on SCr after RC may be confounded by urinary resorption in patients with a continent urinary diversion. 33 Regardless of the method used for defining ineligibility for cisplatin-based chemotherapy, clearly a large proportion of patients with urothelial carcinoma have impaired renal function. New therapeutic approaches are needed for this subset of patients.…”