Evaluation of Surgical Site Infection Rates in Traumatic Surgical Fixation and Arthroplasty Performed in Laminar Flow Versus Non-laminar Flow Theatres During the COVID Pandemic

Introduction Laminar flow (LF) in theatres has become the standard of care in orthopaedic implant surgery. Most of the evidence for laminar flow use is based on arthroplasty surgery, with early studies showing a significant reduction in infections. We conducted a retrospective comparative study to assess surgical site infection (SSI) rates in consecutive patients undergoing surgery for trauma in LF and non-laminar flow (NLF) theatres. Methods Due to COVID-19 safety restrictions, trauma surgery was performed in non-laminar flow theatres during the pandemic. We identified consecutive patients who had trauma surgery pre- and post-pandemic from February 2019 to June 2021 to avoid selection bias. A total of 1809 patients were identified for the study, and the relevant patient details were collected through the hospital operating theatre software (Bluespier) and patient records (Welsh Clinical Portal). There were 917 in the laminar theatre group and 892 in the non-laminar theatre group. For the purpose of this study, we recorded SSI rates within the first 90 days. The two groups were statistically similar in terms of age and gender of the patients. Results Nineteen patients developed surgical site infections in non-laminar flow theatres and 25 patients in laminar flow theatres. There was no significant difference between the SSI rate in laminar flow theatres (2.72%) as compared to non-laminar flow theatres (2.13%) (p=0.399). There was no link between infections and the duration of surgery. Two patients in the laminar flow group were MRSA-positive and were excluded. Conclusion In our study, the laminar flow theatres did not show a statistically significant reduction in surgical site infections. We conclude in the practical environment of trauma theatres the theoretical advantage of laminar flow does not translate to an observable reduction of infections.