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Short-Duration Hypothermia Induction in Rats using Models for Studies examining Clinical Relevance and Mechanisms
Published on: March 3, 2021
Phenylephrine attenuates intra-operative hypothermia during spinal anaesthesia
1Department of Anaesthesiology, Boramae Hospital, Seoul National University, Seoul, Republic of Korea.
The Journal of International Medical Research
|February 12, 2010
Summary
Phenylephrine infusion can prevent core hypothermia during spinal anesthesia by inhibiting body heat redistribution. This treatment maintained higher core temperatures without causing hemodynamic complications in patients undergoing surgery.
Area of Science:
- Anesthesiology
- Physiology
- Pharmacology
Background:
- Inadvertent hypothermia is a frequent complication during spinal anesthesia.
- Core-to-peripheral redistribution of body heat is a primary mechanism for this hypothermia.
Purpose of the Study:
- To test the hypothesis that phenylephrine can attenuate core hypothermia during spinal anesthesia.
- To investigate phenylephrine's effect on body heat redistribution.
Main Methods:
- Prospective randomized study with 20 patients undergoing elective orthopedic surgery under spinal anesthesia.
- Patients received either normal saline (control) or continuous phenylephrine infusion (0.5 microg/kg/min).
- Core temperature, heart rate (HR), and mean arterial pressure (MAP) were monitored.
Main Results:
- The phenylephrine group showed significantly higher mean core temperature at the end of surgery (35.9°C vs. 35.0°C).
- Baseline core temperatures were similar between groups (36.3°C).
- No significant differences in mean HR or MAP were observed between the groups.
Conclusions:
- Continuous phenylephrine infusion effectively attenuated core hypothermia during spinal anesthesia.
- Phenylephrine administration did not result in significant hemodynamic complications.
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