Active Warming during Preanesthetic Period Reduces Hypothermia without Delay of Anesthesia in Cardiac Surgery.

Shinn,  Helen Ki; Kwak,  Young Lan; Oh,  Young Jun; Kim,  Seung Ho; Kim,  Ji Young; Lee,  Mi Hyeon

doi:2005.48.6.S5

Clinical Research Article

Korean Journal of Anesthesiology 2005;48(6):S5-S10.
DOI: https://doi.org/10.4097/kjae.2005.48.6.S5

Active Warming during Preanesthetic Period Reduces Hypothermia without Delay of Anesthesia in Cardiac Surgery.

Helen Ki Shinn, Young Lan Kwak, Young Jun Oh, Seung Ho Kim, Ji Young Kim, Mi Hyeon Lee

¹Department of Anesthesiology and Pain Medicine, Inha University College of Medicine, Incheon, Korea.
²Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea. ylkwak@yumc.yonsei. ac.kr
³Department of Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea.

Abstract

BACKGROUND
Intra-operative hypothermia adversely affects hemodynamics and post-operative recovery in cardiac surgery patients. This study evaluated the efficacy of active warming during the preanesthetic period on the prevention of intraoperative hypothermia in cardiac surgery patients.
METHODS
After gaining the approval of Institutional Review Board and informed consent from the patients, sixty patients undergoing cardiac surgery were divided into control and prewarming group. The control group (n = 30) were managed with warm mattresses and cotton blankets, whereas the prewarming group (n = 30) were actively warmed with a forced-air warming device before anesthesia. Hemodynamic variables and temperature were recorded before anesthesia (Tpre) and at 30 min intervals after anesthesia (T30, T60, and T90).
RESULTS
Before anesthesia, skin temperature was significantly higher in the prewarming group than in the control group. At T90, core temperature was significantly higher in the prewarming group than in the control group. Intraoperative hypothermia (core temperature < 35.5oC) developed by T90 in 78% of patients in the control group and 44% of patients in the prewarming group. Moreover, temperatures below 35oC developed in 58% of the conrol group and 17% of the prearming group.
CONCLUSIONS
Active warming just before anesthesia reduced the incidence and degree of hypothermia in patients undergoing cardiac surgery, with no delay of anesthesia.

Key Words: forced-air warming; hypothermia; off-pump coronary artery bypass graft; prewarming; temperature