Independent testing of the Fisher & Paykel Healthcare MR860 Laparoscopic Humidification System

Abstract

In laparoscopic surgery CO₂ is commonly insufflated at room temperature, with a relative humidity approaching 0%. There has been an increase in utilization of devices to warm and humidify the insufflated gas to avoid potential detrimental effects caused by desiccation. Available data on the performance of these devices are limited. We aimed to conduct independent testing of the Fisher & Paykel MR860 Laparoscopic Humidification System at variable flow rates. A 2.5l insulated chamber was constructed and a digital thermo-hygrometer placed inside it. The humidifier water vessel was weighed and exactly 30.0g of water poured in. 50.0L of CO₂ was insufflated into the chamber via the humidifier at 2.0L/min, 4.0l/min, 6.0l/min, 8.0l/min, and 10l/min using a laparoscopic insufflator. Measurements of temperature and humidity in the chamber were taken at 30 second intervals. After 50.0l of gas was insufflated the water left in the humidifier was weighed, and this was used to calculate the mean absolute humidity of the insufflated gas by the gravimetric method. At every flow rate, > 98.0% relative humidity was achieved in the chamber after less than 30 seconds of insufflation. Using the gravimetric estimate, the humidifier was able to saturate 50.0l of CO₂ to close to saturation humidity at every flow rate tested. The Fisher & Paykel MR860 Laparoscopic Humidification System effectively humidifies insufflated CO₂ at a range of flow rates commonly used in the surgical setting.

Key words::

• CO₂
• insufflation
• humidification system
• peritoneum

Sources of funding: Dr Tarik Sammour is supported by a Surgeon Scientist Scholarship administered by the Royal Australasian College of Surgeons. Dr Arman Kahokehr is supported by the Ruth Spencer Fellowship administered by the Auckland Medical Research Foundation.

Conflict of interest: The humidifier and equipment were supplied on loan from Fisher & Paykel Healthcare, Auckland, New Zealand. Fisher & Paykel Healthcare were not otherwise involved in data collection, analysis, or writeup. There is no conflict of interest pertaining to this publication from the point of view of the authors or their affiliated institution.

Notes