Can Psychological Factors and Colonic Motility Predict Postoperative Complications? An Observational Pilot Study

Abstract

Prolonged postoperative ileus (PPOI) describes delayed bowel function recovery and oral intake intolerance following surgery. PPOI affects up to 30% of colorectal patients, causes discomfort, complication risk, lengthen hospital stays and increases costs. Recent evidence suggests heightened preoperative anxiety may contribute to PPOI by dysregulating gastrointestinal motility patterns. This study aimed to evaluate the feasibility of a large observational study investigating the role of psychological factors on gut function and recovery following major surgery. An observational pilot study was conducted at Auckland City and North Shore Hospitals. Nine colonic and nine non-colonic surgical patients (undergoing major non-spinal orthopaedic, breast or non-bowel-abdominal) were recruited. Surgical anxiety, optimism, depression, stress, and expectations were assessed at baseline. Baseline, preoperative and postoperative colonic electrophysiology and electrodermal activity were measured using Body Surface Mapping Electrocolonography (BSM EColG) and Empatica E4 wristband. Primary outcomes were protocol and device feasibility. Secondary outcomes included preliminary effect sizes between psychological predictors and postoperative bowel function recovery. A factor analysis was completed to create two overall psychological constructs named ‘general negative affect’ and ‘surgical mindset’. Eligibility rates, recruitment rates and sample retention were acceptable in both patient groups. Self-reported measures were appropriate and performed well except the repeated state anxiety measure. Both devices were acceptable, appropriate, uncomplicated to place and worn for the full study duration in most patients. Empatica E4 data quality was moderate due to some missing HRV data and low levels of EDA artefact. EColG demonstrated acceptable connectivity. PPOI was only diagnosed in 33% of the colonic sample. Preliminary analyses were non-significant but suggest increased PPOI risk with negative surgical mindset. General negative affect and negative surgical mindset had mixed non-significant effects on time until overall and individual bowel function recovery was achieved. Exploratory analyses indicate a difference in sympathetic output (p = .002) but not state anxiety between baseline and preoperative timepoints. Eligibility and recruitment processes were feasible and appropriate for this patient population. Patients were accepting of and agreeable to wear the both the BSM EColG and Empatica E4 devices. These devices demonstrated adequate data quality. Current methods and devices are suitable for a large observational study. Preliminary results suggest psychological factors may have deleterious effects on postoperative bowel function recovery.