(C-049) Epidemiology of intraoperative and postoperative complications in patients undergoing left-sided colorectal surgery for benign or malignant colorectal disease in England

Background: Estimates of complication rates following colorectal surgery range widely and are sourced from studies with limited sample size. Comprehensive colorectal surgery complication estimates from a larger, real-world cohort could improve patient safety by informing clinical care.

Objectives: To calculate the cumulative incidence of complications and readmission within 30-days following left-sided colorectal surgery and to characterize post-procedural length of stay.

Methods: This retrospective cohort study identified adult patients undergoing left-sided colorectal surgery in the Hospital Episode Statistics Admitted Patient Care (HES-APC) database between 2014-2018. Patient records were linked to the Clinical Practice Research Datalink GOLD or Aurum database. The index procedure date was defined by the first identified colorectal surgery. The composite complication included: anastomotic leakage, anastomotic bleeding, cardiac arrest, coma, deep vein thrombosis, myocardial infarction, postoperative ileus and intestinal obstruction, pneumonia, postprocedural gastrointestinal bleeding, pulmonary embolism, sepsis, stenosis and/or stricture, stroke, surgical site infection, wound disruption and/or burst abdomen, and death. Complications were identified in HES-APC using ICD-10 diagnosis codes and in GOLD or Aurum using Read and SNOMED codes within 30 days following the index procedure. Death was identified either by discharge status in HES-APC or death recorded in GOLD or Aurum within 30 days following the index procedure date. Readmission was defined as a non-elective hospitalization in HES-APC within 30 days following the index procedure hospitalization discharge. Length of stay was calculated as the number of days from index procedure date to discharge date in HES-APC.

Results: Of 200,279 patients identified in HES-APC who underwent a colorectal procedure, 20,362 were included in the study. The cohort mean (standard deviation) age was 66 (13) years and 53% of patients were male. The most common surgical indication was malignant neoplasm (55%), and the most common primary procedure was Hartmann’s reversal procedure (45%). The cumulative incidence (95% confidence interval (CI)) of any complication was 50.6% (49.9% - 51.3%), with an event rate of 88.3%. The cumulative incidence (95% CI) of 30-day readmission was 15.1% (14.6% - 15.6%) and the median (interquartile range) length of stay was 8 [5-14] days.

Conclusions: Half of patients experienced one or more intraoperative or postoperative complications within 30 days following left-sided colorectal surgery. These findings suggest that improving healthcare delivery will result in impactful gains in patient care and outcomes.