Does laminar flow reduce the risk of early surgical site infection in hip fracture patients?

OBJECTIVE

To determine if there is a difference in the rate of early infection in hip fracture surgery performed under laminar flow and conventional turbulent ventilation.

METHOD

The impact on the rates of early surgical site infection (SSI) in patients who sustained a hip fracture after our trauma theatre was moved from a laminar to a non-laminar flow theatre was assessed. Data was retrospectively collected for six months prior to the merging of the trauma service and six months after. For each operation: age, gender, American Society of Anesthesiologists (ASA) grade, dementia, diabetes, immunosuppressants, anticoagulation, smoking status, duration of surgery, administration of peri-operative antibiotics, surgeon grade, skin closure method, and SSI were extracted from the hospital electronic notes with input from the trust's SSI surveillance team.

RESULTS

259 hip fracture operations were performed during this period. Seven patients were excluded due to incomplete information. There were 95 patients in the laminar flow group and 157 in the non-laminar flow group. There were no SSIs in the laminar flow group and a 3.2% SSI rate (Fishers exact p = 0.16) in the non-laminar flow group. Three were superficial infections and two deep. This difference was not statistically significant. Patient characteristics were included in a Firth logistic regression model which did not show a significant change in the odds ratio.

CONCLUSION

A higher incidence of early SSI was found when hip fracture surgery was performed under non-laminar flow conditions but this difference was not statistically significant. Larger studies may change this outcome.