eP295 - Outcomes in Dialysis Patients After Colorectal Resection: An ACS NSQIP Study

Purpose/Background: Postoperative outcomes after colorectal resections are significantly impacted by the comorbid conditions of the patient. Amongst these, dialysis dependence is considered to be associated with a disproportionally higher incidence of postoperative morbidity and mortality. This is in part due to the fact that these patients have a higher burden of other medical comorbidities.Utilizing the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database, we assessed the incidence of patients on dialysis undergoing colorectal resections and compared their outcomes to patients not on dialysis. We further evaluated the factors associated with adverse perioperative outcomes and mortality among patients on dialysis.We hypothesized that dialysis patients would have higher rates of 30-day morbidity and mortality following colorectal surgery.Methods/Interventions: Patients undergoing colectomy or proctectomy were identified from the ACS-NSQIP database from 2015 to 2021 using the appropriate CPT codes. Patient demographics and perioperative outcomes data were collected and analyzed. Multivariable logistic regression was performed to identify risk factors independently associated with mortality in the study population.Results/Outcomes: A cohort of 457,703 patients were identified, of which 4,980 (1%) were on dialysis prior to surgery. In the dialysis group, the median age was 66 years, 55% were males, 89% had ASA class 3 or 4, and 67% underwent emergency surgery. In the non-dialysis group, median age was 63 years, 48% were males, 60% had ASA class 3 or 4, and 27% underwent emergency surgery.Dialysis patients had an increased incidence of postoperative complications compared to non-dialysis patients, including deep incisional infection (1.4% vs 0.8%), organ/space infection (11% vs 6%), wound dehiscence (2% vs 1%), cardiac arrest requiring CPR (6% vs 1%), myocardial infarction (3 % vs 0.8%), bleeding requiring transfusion (39% vs 9%), deep vein thrombosis (3% vs 1%), sepsis (9% vs 0.3%), and septic shock (28% vs 3%) (Table 1).Dialysis patients had a higher mortality compared to non-dialysis for elective (4% vs 0.4%, P < 0.001) and emergent surgery (27% vs 6%, P < 0.001).In the overall cohort, dialysis dependence was independently associated with mortality (P < 0.001). Within the dialysis population, age over 65, history of COPD, history of CHF, ascites, and emergency surgery were independently associated with mortality (all P < 0.001).Conclusion/

Discussion: In our analysis, we observed that patients on dialysis undergoing colorectal resections were at a higher risk of perioperative morbidity and mortality. The risk of an adverse outcome was substantially higher amongst those with advanced age and undergoing emergency surgery. These patients represent a high-risk group that should be targeted for mitigating strategies to improve perioperative outcomes.Table 1.Rates of complications and 30-day mortality after colorectal resection in dialysis and non-dialysis patients from 2015-2021. All differences are significant with P < 0.001.