Introduction:

While radical cystectomy (RC) remains the gold standard in the management of muscle-invasive bladder cancer, it is associated with high rates of post-operative complications and significant risk of morbidity and mortality perioperatively. Malnutrition is an under-recognized modifiable risk factor for post-operative complications. It remains unclear if pre-operative immunonutrition could improve post-operative outcomes.

Methods:

A retrospective review of 205 patients who underwent RC or pelvic exenteration (PE) for bladder cancer by three surgeons at a single institution between January 2015-April 2019 was performed. Patients who received pre-operative immunonutrition supplementation (PrINS) in the form of an L-arginine based drink (IMPACT®; Nestlé HealthCare Nutrition, Florham Park, NJ, USA) were compared to those who did not. Demographic, comorbidity, preoperative features along with post-operative complications and readmissions were collected. The primary post-operative outcome was development of high grade (Clavien-Dindo III-V) complications. Secondary outcomes included readmission within 30 days, ileus requiring nasogastric tube (NGT) decompression, total parenteral nutrition (TPN) requirement, post-operative infection, time to return of bowel function (ROBF), and length of stay (LOS). Categorical and continuous outcomes were compared between the two groups using Fisher’s exact test and Welch T-test, respectively. Multivariable logistic regression analyses were used to identify predictive factors for primary and secondary post-operative outcomes.

Results:

The characteristics of our cohort are summarized in Table 1. PrINS was received by 51.2% of patients. There was no significant difference in rates of high-grade complications (p=1) between patients who received PrINS and those who did not. However, patients who received PrINS had significantly lower odds of requiring post-operative TPN (p-value = 0.022, OR = 0.45), and of post-operative infection (p = 0.003; OR = 0.39). There was no significant difference in the odds of readmission, ileus requiring NGT decompression, time to ROBF, or LOS. On multivariable regression analysis, when adjusting for age, gender, BMI, Charlson Comorbidity Index, and  operative features (RC vs APE, robotic-assisted versus open approach, type of surgical diversion, any concomitant surgery), PrINS was a significant predictor of post-operative infection (p = 0.008; OR = 0.234), but not for high grade complications, readmission, ileus requiring NGT decompression, needing TPN, time to ROBF, or LOS (Table 2).

Conclusion:

In this large retrospective patient series, we found that pre-operative immunonutrition with an L-arginine-based oral supplement, for 5 days prior to radical cystectomy was an independent predictor of reduced risk for post-operative infections, one of this procedure’s most common complications. Immunonutrition did not significantly affect the odds of high grade complications, readmission, ileus requiring NGT, needing TPN, time to ROBF, or LOS.

Funding: N/A