Control of body temperature during abdominal aortic surgery

Area of Science:

• Anesthesiology
• Critical Care Medicine
• Physiology

Background:

• Maintaining normothermia during anesthesia is crucial for preventing perioperative cardiocirculatory complications.
• While warming inspired gases is common, the impact of low flow anesthesia and heat and moisture exchangers on body temperature patterns remains unclear.

Purpose of the Study:

• To evaluate the effect of low fresh gas flow rates versus high fresh gas flow rates in a circle anesthesia system on mean body temperature.
• To assess the combined influence of low flow anesthesia and heat and moisture exchangers on body temperature maintenance.

Main Methods:

• A clinical trial involving 40 patients undergoing anesthesia.
• Patients were divided into two groups: one ventilated with a non-rebreathing circuit and the other with a circle system using low fresh gas flow rates.
• All patients utilized a hydrophobic heat and moisture exchanger; mean body temperature was monitored at five points.

Main Results:

• A significantly lower decrease in mean body temperature was observed 40 minutes after initiating mechanical ventilation in the low flow anesthesia group (P < 0.01).
• The use of low fresh gas flow rates in conjunction with a heat and moisture exchanger demonstrated a superior ability to mitigate the decline in mean body temperature.

Conclusions:

• Anesthesia utilizing low fresh gas flow rates and a heat and moisture exchanger effectively reduces the fall in mean body temperature compared to high fresh gas flow rates.
• This finding suggests that optimizing fresh gas flow is a viable strategy for intraoperative temperature management.