Visceral protection in total arch replacement for aortic dissection: Effect of lower body hypothermia

Optimal hypothermia strategy for total arch replacement in acute type A aortic dissection (ATAAD) is unclear. A higher temperature during circulatory arrest might reduce tolerance to ischemia for visceral organs. We sought to investigate the effect of hypothermia on visceral protection.

From January 2010 to December 2019, 1138 consecutive patients underwent total arch replacement combined with frozen elephant trunk for acute type A aortic dissection. The data were retrospectively collected and analyzed. Visceral organ injury and visceral-related adverse outcomes were defined as acute renal failure or spinal cord injury or both. Multivariate logistic regression analysis and multivariate linear regression model were used.

The mean age of patient was 46.9 ± 10.0 years, with a male preponderance (79.6%). Operative mortality was 6.1% (69 patients). Spinal cord injury occurred in 55 (4.8%) patients and 133 (11.7%) patients had acute renal failure. In the multivariate logistic regression model, neither bladder temperature (odds ratio [OR] 0.971, 95% confidence interval [CI] 0.922-1.024, p = .278) nor circulatory arrest duration (OR 1.017, 95% CI 0.987-1.047, p = .267) significantly associated with visceral-related adverse outcomes. Female, lower limb malperfusion, age, cardiopulmonary bypass (CPB) duration and preoperative serum creatinine level were independent risk factors of visceral-related outcomes. There was a significant negative correlation between bladder temperature and CPB duration in multiple linear regression model (β = -3.67, p < .0001).

Bladder temperature had no effect on outcomes related to visceral protection under the premise of short circulatory arrest duration, but female gender, lower limb malperfusion, age, CPB duration, and preoperative serum creatinine level were independent risk factors. Bladder temperature negatively correlated to CPB duration.