Hypothermia plus thiopental: prolonged electroencephalographic suppression

Area of Science:

• Anesthesiology
• Neuroscience
• Cardiovascular Surgery

Background:

• Hypothermic cardiopulmonary bypass (CPB) is used in cardiac surgery.
• Anesthetic agents are administered during CPB.
• The effects of thiopental on brain activity during hypothermia require further investigation.

Purpose of the Study:

• To investigate the duration of EEG suppression in patients undergoing hypothermic CPB.
• To evaluate the impact of thiopental administration timing and dosage on EEG suppression.
• To assess the combined effect of thiopental and hypothermia on cerebral electrical activity.

Main Methods:

• Comparison of EEG suppression duration across three patient groups undergoing hypothermic CPB (25-30°C).
• Group I: received thiopental for induction, post-CPB, and post-emergence.
• Group II: received no thiopental.
• Group III: received thiopental during CPB only.

Main Results:

• Group I showed a prolonged EEG suppression of 26.1 min compared to 4.8 min in Group II (no thiopental).
• Group III (single thiopental dose during CPB) exhibited 29.3 min of EEG suppression.
• Thiopental administration was associated with mild to moderate cardiovascular depression.

Conclusions:

• Combining thiopental with hypothermia during CPB leads to profound depression of cerebral electrical activity.
• This combination likely impacts cerebral metabolism.
• Careful consideration of thiopental administration is warranted during hypothermic CPB.