The effect of anaesthetic use on healing in sub cutaneous abscess management: a retrospective before and after cohort study

Introduction There is wide variation in the management of simple subcutaneous abscesses in the UK and no national guidelines describing best practice. During the SARS-CoV-2 pandemic, regional or local anaesthesia (LA) use was recommended instead of general anaesthesia. This study aimed to assess the effect of anaesthetic use on outcomes following incision and drainage (I&D) of simple subcutaneous abscesses. Methods Two cohorts of patients undergoing abscess incision and drainage at St. James’ University Hospital in Leeds were identified retrospectively over a 14-week period before (P1) and after (P2) the introduction of the COVID-19 anaesthetic guidelines. The number of follow-up appointments for repacking and representation to healthcare services 30 days after I&D were used as surrogate endpoints for wound healing. Results A total of 133 patients were included (n=70, P1 and n=63, P2). Significantly more procedures were performed under LA after the intervention (84.1% vs 5.7%; p<0.0001) with a significant reduction in wound packing (68.3% vs 87.1%; p=0.00473). Follow-up analysis found no significant difference in the median number of follow-up appointments (7.46 vs 5.11; p=0.0731) and the number of patients who required ongoing treatment after 30 days (n=14, P1 vs n=14, P2; p=0.921). Conclusions Drainage of simple subcutaneous abscess under 5cm in diameter is safe under LA, with no significant difference in surrogate endpoints of wound healing observed in this patient cohort. Recurrent packing may not be required. Future work should explore patient-reported outcomes, including pain management, cosmesis and the cost and sustainability implications of a change in this common procedure