Impact of Using Blood Warmer During Continuous Kidney Replacement Therapy in Patients With Acute Kidney Injury

Abstract

Purpose We investigated the impact of blood warmer use on hypotensive episodes in patients with acute kidney injury (AKI) receiving continuous kidney replacement therapy (CKRT). Materials and Methods We included patients with AKI undergoing CKRT between January 1, 2012, and January 1, 2021, at a tertiary academic hospital. Hypotensive episodes were defined as mean arterial pressure (MAP) <60 mm Hg or a decrease in MAP by ≥10 mm Hg, systolic blood pressure (SBP) < 90 mm Hg or a decrease in SBP by ≥20 mm Hg, or increased vasopressor requirement. These were analyzed by Poisson regression with repeated-measures analysis of variance using generalized estimation equation. Results There were 669 patients with AKI that required CKRT. Use of blood warmer on first day of CKRT was in 324 (48%) patients. Incidence rate ratio of hypotensive episodes during the first 24-h of CKRT in patients where a blood warmer was used was 1.06 (95% confidence interval [CI]: 0.98-1.13) compared to those where blood warmer was not used. This did not change in adjusted model. Overall, the within-subject effect of temperature on hypotensive episodes showed that higher temperature was associated with fewer episodes (0.94, 95% CI: 0.9-0.99 per 10 degrees increase, P = .007). Conclusion Blood rewarming was not associated with hypotensive episodes during CKRT.