Quantifying postoperative recovery using wearable activity monitors following abdominal wall surgery: The AbTech trial

PURPOSE This work aimed to investigate the validity of Wearable Activity Monitors (WAMs) as an objective tool to measure the return towards normal functional mobility following abdominal wall surgery. This was achieved by quantifying and comparing pre- and postoperative physical activity (PA). METHODS A multi-centre, prospective, observational cohort study was designed. Patients undergoing abdominal wall surgery were assessed for eligibility and consented for study participation. Participants were asked to wear a WAM on the wrist of their dominant hand (AX3, Axivity) at least 48 hours pre-operatively, for up to 2 weeks post-op, and then again after 6 months postop for 48 hours. RESULTS A cohort of 20 patients were recruited in this validation study with a mean age of 47.3 ± 13.0 years. Post operation, the percentage median PA (±IQR) dropped to 32.6% (20.1), while on day 14, PA had reached 64.6% (22.7) of the preoperative value providing construct validity. Activity levels at > 6 months postop increased by 16.4% on average when compared to baseline preoperative physical activity, p=0.046. CONCLUSION This study demonstrates that WAMs are valid markers of postoperative recovery following abdominal wall surgery. This was achieved by quantifying the reduction in PA post-operation, which has not been previously shown. In addition, this study suggests that abdominal wall surgery improves patient quality of life via increased functional mobility at 6 months postop. In the future, this technology could be used to identify the patient and surgical factors that are predictors of outcome following abdominal wall surgery.