783 Do We Need Laminar Flow in Trauma?

Abstract Aim Laminar flow in theatres has become standard of care in orthopaedic implant surgery. Most of the evidence for laminar flow use is based on arthroplasty surgery, with early studies showing 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 laminar and non-laminar flow theatres. Method Due to COVID restrictions our trauma care provision was restructured. This resulted in trauma surgery being performed in non-laminar flow theatres. We identified consecutive patients who had trauma surgery pre and post pandemic from February 2019 to June 2021 to avoid selection bias. There were 1010 in laminar theatre group and 1000 in non-laminar theatre group. SSI rates within the first 90 days. The two groups were statistically similar in terms of age and gender of the patients. Results 28 patients developed surgical site infections in non-laminar flow theatres and 29 patients in laminar flow theatres. There was no significant difference between the SSI rate in laminar flow theatres (2.87%), as compared to non-laminar flow theatres (2.80%) (p = 0.92034). There was no link between infections and duration of surgery. 2 patients in the laminar flow group were MRSA positive and were excluded. Conclusions In our study, 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.