Editorial Comment to Impact of early postoperative creatinine increase on mid‐term renal function after cystectomy

Abstract

Renal function decline often occurs after radical cystectomy (RC), both in the acute and chronic phases, although the bilateral kidneys are not manipulated in the majority of cases.Preservation of renal function in RC has clinical relevance; in that, patients may become candidates for adjuvant platinum-based chemotherapy, as recommended by the current guidelines. 1 Furthermore, as the chance of distant metastasis after RC cannot be ignored, preserved renal function would also determine eligibility for "platinum fitness" in this setting. One possible mechanism of long-term renal function decline after RC is thought to be related to hydronephrosis resulting from ureteral-enteral anastomosis in the ileal conduit or orthostatic neobladder; another may be perioperative acute kidney injury (AKI), which is beginning to be accepted as an independent risk factor for chronic kidney disease. 2 To date, evidence on the impact of perioperative AKI after RC on long-term renal function is limited. In the present study by Beilstein et al., AKI, defined by plasma creatinine change within 24 h, was shown to independently compromise chronic renal function. 3 Although the authors hesitated to conclude that the observed findings have strong clinical relevance, difference of 6.3 mL/min of glomerular filtration rate can be considered to have an impact on platinum eligibility, especially given the trend of bladder cancer patients becoming older. Determining AKI by a single-time blood test, as in the study, also has merit as it is easily applicable in daily practice. Unfortunately, as options for effective intervention for AKI, once occurred, are limited, maximum prevention is of utmost importance.How can we protect patients from postoperative AKI after RC? Justification of hemodynamic status during surgery, as the authors argued, is one of the answers and relies on anesthesiologist management. Surgery itself also requires continuous refinement. In addition to avoiding unnecessary manipulation of the ureters and minimizing operation length, minimization of ureteral clamping may contribute to better renal function preservation. 4 In contrast, the introduction of an enhanced recovery after surgery protocol, now widely utilized, may require extra caution to reduce the risk of AKI. 5 However, more data on intra-and pre/post-operative risk factors for renal function loss are needed, and such investigations are highly warranted.