Comparing Sequential vs Simultaneous Tourniquet Inflation in Bilateral Total Knee Arthroplasty

Abstract

Background: There is little evidence on outcomes of tourniquet use during bilateral total knee arthroplasty (BTKA). Tourniquet use in BTKA effects postoperative outcomes and efficiency inside the operating room. This study evaluates the safety and efficacy of simultaneous tourniquet inflation in BTKA. Materials and Methods: A retrospective review was performed on BTKA patients between March 2013 and May 2018. A total of 285 patients were divided into 2 cohorts. Patients in the simultaneous cohort had concomitant elevation of both tourniquets, but the sequential cohort did not. Perioperative variables were collected, and postoperative complications were tracked for a minimum of 90 days. Patients followed a uniform postoperative protocol. Complications were grouped by category to increase statistical power and compared using a noninferiority test. "Clinically noninferior" was defined as a margin 5%. Results: The simultaneous cohort had significantly (P < .05) higher American Society of Anesthesiologists class and smokers. Tourniquet time, delta hemoglobin, and surgical time were significantly lower. For the complication categories of "Any Thrombotic Event", "Respiratory", and "Soft Tissue/Wound", the difference in occurrence rates was no more than 2.8%, 2.8%, and 5.2% between cohorts, respectively. The "Cardiovascular (non-MI)" group was no more than 9.3% different, that is, authors are 95% confident that 3 of 4 complication categories meet the clinically noninferior threshold. Conclusion: The study demonstrates the noninferiority of simultaneous as compared to sequential tourniquet inflation in BTKA. Patients with cardiac history may need sequential inflation or staged TKA. The information presented in the study assists surgeons in safely and efficiently performing BTKA.