The Effect of Operating Room Size on Orthopaedic Surgical Site Infection Rates.

Objective: With many preventable causes of surgical site infections (SSIs) identified, the effect of operating room (OR) size on SSI rates has not been assessed. This study investigated the effect of OR size on incidence of SSIs for orthopaedic procedures.

Background: SSIs remain a common complication within the perioperative realm. Responsible for increasing length of hospitalization and costs, SSIs result in a decreased quality of life for patients.

Methods: A retrospective review of 11,163 patients who underwent orthopaedic surgery-including total knee and hip arthroplasties, laminectomies, and spinal fusions-between January 2018 and January 2020 were reviewed. Total net square footage (NSF) of all ORs was recorded, and incidence of SSIs was calculated. Cases were categorized based on the size of the OR (small: 250 to 399 NSF; medium: 400 to 549 NSF; and large: 550 to 699 NSF). Chi-square analysis compared infection rates between the different OR sizes, and a binary logistic regression model identified other predictors of infection.

Results: Overall, 137 patients (1.2%) developed an SSI. Of these infections, 16 (11.7%) occurred in small ORs, 83 (60.6%) in medium ORs, and 38 (27.7%) in large ORs. The incidence of SSIs was 0.7% in small ORs, 1.3% in medium ORs, and 1.8% in large ORs. Factors found to significantly impact SSI's included medium-sized ORs, younger patients, procedure type (fusions and emergencies/traumas), longer procedures, and higher American Society of Anesthesiologists scores (>3).

Conclusion: Our study shows that OR size in addition to various other perioperative parameters plays a role in the rate of SSIs for orthopaedic procedures.

Level Of Evidence: Retrospective Cohort Study; Level III Evidence.