Effect of Operative Time on Short-Term Adverse Events After Isolated Anterior Cruciate Ligament Reconstruction

Abstract

Background: A longer operative time has been previously recognized as a risk factor for short-term complications after various orthopaedic procedures; however, it has yet to be investigated as an independent risk factor for postoperative complications after anterior cruciate ligament (ACL) reconstruction. Purpose: To identify whether a longer operative time in ACL reconstruction is an independent risk factor for the development of postoperative complications, hospital readmissions, or an extended length of stay within 30 days of the index procedure. Study Design: Descriptive epidemiology study. Methods: Patients undergoing ACL reconstruction between 2005 and 2016 were identified using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Cases with concomitant procedures were excluded from the analysis. We evaluated the association between operative time and preoperative variables such as patient age, sex, body mass index, comorbidities, and procedure. Correlations between adverse events and operative time, while controlling for the above preoperative variables, were calculated using multivariate Poisson regression with robust error variance. Results: A total of 14,159 procedures were included in this investigation. The mean patient age was 32.6 ± 10.8 years, the mean body mass index was 27.7 ± 6.5 kg/m2, and the mean operative time was 89.7 ± 28.6 minutes. Patients who were between the ages of 18 and 30 years (mean operative time, 95.1 ± 27.8 minutes; relative risk [RR], 17.7; P < .001), male (mean operative time, 91.9 ± 28.3 minutes; RR, 4.7; P < .001), and nondiabetic (mean operative time, 89.8 ± 28.6 minutes; RR, 7.1; P = .011) were associated with a longer operative duration. The overall complication rate was 1.1%. After adjusting for demographic characteristics and procedures, 15-minute incremental increases in operative duration were associated with an increased risk of deep vein thrombosis (RR, 1.12; P = .042), surgical site infections (RR, 1.21; P = .001), and sepsis (RR, 1.66; P < .001) as well as increased readmission rates (RR, 1.23; P = .001) and an extended length of stay (RR, 1.18; P = .008). Conclusion: While the overall adverse risk rate after ACL reconstruction remains low, marginal increases in operative time are associated with an increased risk of adverse events such as deep vein thrombosis, surgical site infections, sepsis, an extended length of stay, and readmissions. Thus, the operating physician and surgical staff should make all efforts to coordinate and prepare for each case to maximize surgical efficiency.