Carbon dioxide gas heating inside laparoscopic insufflators has no effect

Area of Science:

• Minimally invasive surgery
• Surgical technology
• Patient safety

Background:

• Laparoscopic surgery increasingly uses high-flow insufflators, increasing the risk of hypothermia.
• Carbon dioxide (CO2) gas used for insufflation can lead to a drop in patient body temperature.
• The effectiveness of internal gas heating in laparoscopic insufflators for preventing hypothermia is debated.

Purpose of the Study:

• To evaluate the efficacy of internal gas heating in laparoscopic insufflators for preventing hypothermia.
• To compare CO2 gas temperature at various points in the insufflation system for different insufflator models.
• To determine if internal gas heating provides a clinically significant benefit in maintaining CO2 gas temperature at the patient site.

Main Methods:

• A computer-based data acquisition model was used for comparison.
• Five standard insufflators were tested: one with internal gas heating (Snowden Pencer) and four without (Storz Endoflator, Storz Laparoflator, Richard Wolf, BEI Medical).
• CO2 gas temperature was measured at the insufflator exit and the end of a 3-meter insufflation hose.

Main Results:

• The Snowden Pencer insufflator showed increased gas temperature at the exit (max 35.4°C), dependent on flow rate.
• For all tested insufflators, CO2 gas temperature returned to room temperature (-0.22 to +1.10°C) at the end of the 3-meter insufflation hose.
• Even at high flow rates (up to 20 L/min), CO2 gas reached room temperature by the time it reached the patient.

Conclusions:

• Internal gas heating in laparoscopic insufflators does not significantly raise CO2 gas temperature by the time it reaches the patient.
• The distance between the insufflator and the patient negates any warming effect from internal gas heating.
• Marketing of internal gas heating as a hypothermia prevention method in laparoscopy is misleading due to a lack of measurable patient benefit.