We demonstrated that continent diversion does not increase complication risk after radical cystectomy for bladder cancer. Given the higher preponderance of comorbid conditions among ileal conduit subjects, the finding of increased medical complications among these subjects on unadjusted analyses is not surprising. Accounting for case-mix differences with propensity scores techniques, these differences persisted, albeit with a smaller effect size.
Despite increased technical complexity and incorporation of a larger bowel segment into continent urinary tract reconstructions, the rate of surgical complications was not higher among these subjects. The lower risk of medical and surgical complications likely produced the differential disposition outcomes seen for continent diversion subjects. Those reconstructed with a continent diversion had an 8% lower risk of discharge to a subacute facility. At least 1 postoperative complication was shown to increase admission charges by $15,000 and length of stay by 4 additional days.11
Complications may increase the likelihood of postoperative disability requiring nursing care and thus, alternate disposition.
Retrospective series from high-volume academic centers corroborate our results.12–14
Compared with these series from high-volume tertiary referral centers, our analysis attempts to minimize selection bias and examines complications outcomes broadly through inclusion of small practices that may perform few cystectomies. Tertiary referral centers likely have dedicated surgeons, nursing care, and ancillary support to facilitate efficient delivery of care for recipients of orthotopic or cutaneous neobladders. Our results offer more generalizable estimates of complications after cystectomy and urinary diversion.
Among covariates, age and comorbidity were associated with postoperative medical and surgical complications. Older patients had a higher risk of cardiovascular events and any medical complication, as well as increased odds of discharge to a subacute facility. Age confers a stepwise increase in postoperative cardiovascular events regardless of the surgery performed.15
Age also correlates with functional status, known to correlate with occurrence of any postoperative complication and a risk factor for postoperative disability.16
Yet age alone should not affect the consideration of radical cystectomy, as elderly patients derive a survival benefit from extirpative treatment compared with those managed conservatively.17
Rather, advanced age mandates more diligent attention to preoperative medical optimization.
Similarly, certain comorbid conditions were associated with dramatically increased odds of postoperative medical and surgical complications. A medical history of congestive heart failure immediately attunes a surgical provider to the increased risk of perioperative adverse events; however, beyond intuitive promotion of cardiovascular and respiratory events, heart failure patients suffer worse bowel and urinary outcomes and have higher odds of any surgical complication. Preoperative weight loss likewise impacts medical and surgical complications. Impaired wound healing imposed by poor nutrition likely mediates the increased surgical risk. Among cystectomy patients, preoperative serum albumin inversely correlates with risk of 1 or more postoperative complications.16
Among a cohort of veterans, preoperative serum albumin was a more powerful correlate of postoperative events than age or comorbidity.18
Attention to nutritional interventions among those with preoperative weight loss may improve postoperative outcomes.
Our results may decrease provider reluctance to consider continent urinary diversion when counseling patients about reconstructive options after radical cystectomy for invasive bladder cancer. Patient-related concerns regarding consideration of continent reconstruction often relate to the aggressiveness of the cancer, the presence of comorbid chronic kidney disease, their functional status and ability to perform self-catheterization, if needed, and the overall health status of the patient and ability to withstand longer anesthetics. Provider-specific concerns relate to the increased operative time because of the technical complexity of continent diversions, the possibility of increased morbidity and mortality, and the increased nursing care in the convalescent period. Demonstration of the safety of continent urinary diversion may mitigate these surgical concerns.
Regionalization of care for complex surgical procedures has been proposed as a solution to operations with defined volume-outcome relations. For these operations, high-volume providers have lower mortality rates than low-volume providers. Cancer operations with significant mortality rate differentials include pancreatectomy and esophagectomy.19
A similar volume-outcome relation was not identified for radical cystectomy.20
However, the benefits of regionalization extend beyond survival benefits; patients treated by high-volume cystectomy providers are more likely to undergo continent diversions.1
These high-volume surgeons may have a level of expertise with continent diversions such that they can offer this reconstruction solely on the basis of patient clinical characteristics. At the same time, patients may be unwilling to travel long distances to high-volume surgeons and may face longer wait times for surgery if they do. Delays in definitive extirpation >3 months have been associated with decreased bladder cancer-specific survival.21
More feasibly, we must disseminate those processes affiliated with utilization of continent urinary diversion. Although volume and academic affiliation correlate with use of continent reconstruction,1
mean cystectomy volume at hospitals in which >40% of diversions were continent was 0.8 cystectomies annually in a nationally representative cohort.22
Beyond academic centers, in which 35% to 52 % of cystectomies are followed by continent reconstructions,23–25
some low-volume providers prioritize continent reconstruction. The differences between these and providers who eschew consideration of continent techniques must be better understood to increase rates of continent reconstruction from the low rate of 16.5% documented in this study.
The current study is confounded by several limitations. First, we were unable to account for cancer-specific characteristics and patient surgical history in our complications outcomes. The inability to stratify utilization of differing reconstruction types by stage or grade or to examine complications outcomes by those same pathologic parameters may have affected our analyses. More aggressive cancers require more extensive dissection that can predispose patients to adverse postoperative events. These patients more commonly undergo ileal conduit diversion. Failure to account for cancer characteristics may bias the ileal conduit group toward worse complications outcomes. Similarly, those undergoing neoadjuvant chemotherapy may have different tendencies toward certain diversions and, possibly, varying complications outcomes. Those with an extensive history of prior abdominal surgery are predisposed to adverse surgical events. The increased difficulty of the surgery likely predisposes these patients to ileal conduit diversion as well, further biasing these subjects to worse outcomes.
We were also restricted to assessing complication outcomes that occurred during the index admission. Adverse postoperative events that postdated the index admission and that are common after radical cystectomy and urinary diversion may include readmissions for infections, bowel obstructions and other gastrointestinal complications, stoma complications, stones, and metabolic consequences of bowel reconstructions.26
These may increase the burden of care on recipients of continent diversions if they are predisposed to higher rates of these adverse events. Future work should examine long-term sequelae of urinary diversion after radical cystectomy.
In using propensity score methods, we assume that the patient- and hospital-level covariates are balanced between subjects with similar propensity scores. If unobserved characteristics determined diversion type, our results would be confounded by persistent selection bias. For this analysis, several unmeasured variables may have influenced the type of reconstruction performed, including patient preferences and self-efficacy, body habitus, performance status, social support, and cancer severity. Unmeasured variables may likewise affect our complications outcomes, such as the use of clinical care pathways, surgeon training, and hospital nursing magnet status. Hospital characteristics associated with use of continent urinary diversion are likely associated with many of these unmeasured variables, such as use of clinical care pathways, which may be associated with reduced complication rates among continent diversion patients. We assume, however, that the observed characteristics of our sample—patient sociodemographics, patient comorbidity, hospital type—are associated with those unobserved characteristics such that balance is maintained between continent diversion subjects and those diverted with an ileal conduit. Lastly, we assessed morbidity in the immediate postoperative period. Given the data source, we were unable to compare morbidity incurred beyond the index admission, and thus were unable to represent long-term outcomes including readmissions and reoperations.
Despite these limitations, we demonstrated that the type of urinary diversion after radical cystectomy for bladder cancer is not associated with the risk of immediate postoperative complications. These results may decrease provider reluctance to consider a more complex diversion when counseling patients with invasive bladder cancer about reconstruction options after radical cystectomy.