The effect of warm and humidified gas insufflation in gynecological laparoscopy on maintenance of body temperature: a prospective randomized controlled multi-arm trial

Abstract

Background: Hypothermia is defined as a decrease in body core temperature to below 36 °C. If intraoperative heat-preserving measures are omitted, a patient's temperature will fall by 1 - 2 °C. Even mild forms of intraoperative hypothermia can lead to a marked increase in morbidity and mortality. Using warm and humidified gas insufflation in laparoscopy may help in the maintenance of intraoperative body temperature.

Methods: In this prospective randomized controlled study, we investigated effects of temperature and humidity of the insufflation gas on intra- and postoperative temperature management. 150 patients undergoing gynecologic laparoscopic surgery were randomly assigned to either insufflation with non-warmed, non-humidified CO2 with forced air warming blanket (AIR), humidified warm gas without forced air warming blanket (HUMI) or humidified warm gas combined with forced air warming blanket (HUMI+). We hypothesized that the use of warmed laparoscopic gas would have benefits in the maintenance of body temperature and reduce the occurrence of hypothermia.

Results: The use of warm and humidified gas insufflation alone led to more hypothermia episodes with longer duration and longer recovery times as well as significantly lower core body temperature compared to the other two groups. In the comparison of the AIR group and HUMI + group, HUMI + patients had a significantly higher body temperature at arrival at the PACU (Post Anaesthesia Care Unit), had the least occurrence of hypothermia and suffered from less shivering.

Conclusion: The use of warm and humidified gas insufflation alone does not sufficiently warm the patients. The optimal temperature management is achieved in the combination of external forced air warming and insufflation of warm and humidified laparoscopy gas.

Trial registration: ClinicalTrials.gov NCT02781194.

Keywords: Body temperature; Hypothermia; Warm humidified CO2; Warm management.

Conflict of interest statement

Julia Wittenborn, Deborah Matthei, Julia van Waesberghe, Felix Zeppernick, Magdalena Zeppernick, Svetlana Tchaikovski, Markus Breuer, Ana Kowark, András Keszei, Elmar Stickeler, Norbert Zoremba, Rolf Rossaint, Christian Brülls, Ivo Meinhold-Heerlein have no conflicts of interest or financial ties to disclose.

© 2022. The Author(s).

Figures

Fig. 1

Consort flow diagram

Fig. 2

Duration of hypothermia: Boxplots of duration of hypothermia in the TePaLa study by intervention groups. Dots represent jittered data points

Fig. 3

Recovery time: Boxplots of time duration from the lowest measured temperature   = 36 °C after hypothermia that was not followed by any subsequent measurement 

Fig. 4

Boxplot of pre-, peri- and postoperative temperature measurements by intervention groups

Fig. 5

Estimated treatment effects on temperature (relative to intervention group AIR). Line ranges are pointwise 95% confidence intervals. Treatment effects are estimated using a linear model with timepoints (1,2,3,4), treatment (1,2,3) and time point interactions (no treatment main effect), stratification (1,2), and blocks (1 to 6) as fixed effects and random intercepts grouped by subjects

Fig. 6

Temperature trends after averaging all temperature data within the different groups. The straight fat line depicts the slope

Fig. 7

Boxplot: Duration of PACU stay (in min) by groups