Validity of the I-FEED score for postoperative gastrointestinal function in patients undergoing colorectal surgery

Abstract

Background: Postoperative ileus (POI) is common after gastrointestinal surgery and is associated with significant morbidity and costs. However, POI is poorly defined. The I-FEED score is a novel outcome measure for POI, developed by expert consensus. It contains five elements (intake, response to nausea treatment, emesis, exam, and duration, each scored with 0, 1, or 3 points) and classifies patients into normal, postoperative gastrointestinal intolerance (POGI), and postoperative gastrointestinal dysfunction (POGD). However, it has not yet been validated in a clinical context. The objective was to provide validity evidence for the I-FEED score to measure the construct of POI in patients undergoing colorectal surgery.

Methods: Data previously collected from a clinical trial investigating the impact of different perioperative fluid management strategies on primary POI in patients undergoing elective laparoscopic colectomy (2013-2015) were analyzed. Patients were managed by a longstanding Enhanced Recovery program (expected length of stay (LOS): 3 days). Daily I-FEED scores were generated (normal 0-2, POGI 3-5, POGD 6+ points) up to hospital discharge or postoperative day 7. Validity was assessed by testing the hypotheses that I-FEED score was higher (1) in patients with longer time to GI3 (tolerating diet + flatus/bowel movement), (2) with longer LOS (> 3 days vs shorter), (3) in patients with complications vs without, (4) in patients with poorer recovery (measured by Quality of Recovery-9 questionnaire).

Results: A total of 128 patients were included for analysis (mean age 61.7 years (SD 15.2), 57% male, 71% malignancy, and 39.1% rectal resection). Median LOS was 4 days [IQR3-5], and 32% experienced postoperative in-hospital morbidity. Overall, 48% of patients were categorized as normal, 22% POGI, and 30% POGD. The data supported all 4 hypotheses.

Conclusions: This study contributes preliminary validity evidence for the I-FEED score as a measure for POI after colorectal surgery.

Keywords: Colorectal surgery; I-FEED; Ileus; Validation.