Rectus sheath catheter analgesia versus standard care following major abdominal surgery: An observational study of 911 patients.

<bold>Background: </bold>It is unknown whether rectus sheath catheter (RSC) continuous infusion of local anaesthetic is superior to standard post-operative opiate analgesia following major abdominal surgery. Previous audit in our Trust had suggested RSC was very effective and reduced opiate analgesia use. We aimed to see if this was maintained as the technique became more widespread comparing clinical outcomes and post-operative opiate analgesia requirements between patients who had RSCs and those that did not following major abdominal surgery over a 32-month period.<bold>Methods: </bold>A retrospective observational study investigated patients who had major abdominal surgery at a single centre in the UK between January 2018 and August 2020. Placement of RSCs was at the discretion of the surgical team according to their own personal choice. All patients having the procedure in both an elective and non-elective setting have been included in this study, including patients requiring higher level care after emergency surgery. Clinical outcomes and post-operative opiate analgesia requirements (oral and intravenous) were analysed using multivariate logistic regression models adjusting for American Association of Anesthesiologists (ASA) grade and type of surgery (emergency vs elective and open vs laparoscopic).<bold>Results: </bold>There were 911 patients; 276/911 (30.3%) RSC and 635/911 (69.7%) non-RSC. Median age was 64 (52-74) years; 51.6% were male. In the adjusted models, RSC was associated with a reduced likelihood of serious complications (OR 0.49 (95% CI 0.33, 0.72); p < 0.001) and lower length of stay in ICU (OR 0.95 (95% CI 0.91, 0.99); p = 0.029). RSC was not associated with reduced post-operative opiate analgesia use. There were 3/276 (1.1%) adverse events following RSC placement during the period of data collection.<bold>Conclusions: </bold>Clinical outcomes may be superior for patients following major abdominal surgery when RSCs are placed for post-operative analgesia but uncertainty remains. This paper highlights the difficulty with retrospective non-selected data in answering this question. High quality prospective randomised data are required to determine the effects on clinical outcomes and post-operative opiate analgesia requirements. [ABSTRACT FROM AUTHOR]