Continuous intraoperative temperature measurement and surgical site infection risk: analysis of anesthesia information system data in 1008 colorectal procedures

Abstract

Objectives: To investigate the association between intraoperative temperature and surgical site infection (SSI) in colorectal surgery with anesthesia information system data.

Methods: Continuously measured intraoperative anesthesia information system temperature data for adult abdominal colorectal surgery procedures at a large tertiary center for 1 year were linked to 30-day American College of Surgeons National Surgical Quality Improvement Program SSI outcomes. Univariable and multivariable analyses of SSI to descriptive temperature statistics, absolute and relative temperature threshold times, and other clinically relevant variables were performed.

Results: Overall, 1008 patients (48% female, median age: 53 years) underwent major colorectal procedures (7% emergent, 72% open, 173 ± 95 minutes mean procedure time) with median intraoperative temperature 36.0°C, using active rewarming in 92% and 1-hour presurgical antibiotic administration in 91%. Thirty-day overall and organ/space infection rates were 17.4% (175) and 8.5% (86). Maximum, minimum, ending, and median temperatures were similar for those with or without SSI (36.6°C vs 36.5°C, 34.9°C vs 35.0°C, 36.4°C vs 36.2°C, and 36.1°C vs 36.0°C, P = not significant) and percent minutes using incremental cutoffs failed to correlate SSI with temperature. Absolute minutes for higher temperature cutoffs correlated with SSI because of longer procedure times. On multivariable analysis, factors associated with SSI were preoperative diabetes [odds ratio: 1.81 (1.07-3.07), P = 0.022] and blood loss of more than 500 mL [odds ratio: 1.61 (1.01-2.58), P = 0.047].

Conclusions: Although active rewarming remains an accepted and valid process measure, highly granular anesthesia information system temperature data did not demonstrate a correlation between temperature measures and SSI. SSI prevention efforts should focus on more efficacious interventions as opposed to currently mandated publicly reported normothermia measures.