Medical Gas Research

RESEARCH ARTICLE
Year
: 2020  |  Volume : 10  |  Issue : 1  |  Page : 27--29

Temperature loss by ventilation in a calorimetric bench model


Holger Herff1, Daniel C Schroeder1, Kevin Bowden2, Peter Paal3, Thomas Mitterlechner4, Volker Wenzel5 
1 Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Cologne, Cologne, Germany
2 O-Two Medical Technologies Inc., Brampton, Canada
3 Department of Anaesthesiology and Intensive Care Medicine, Hospitallers Brothers Hospital, Paracelsus Medical University, Salzburg, Austria
4 Department of Anesthesiology, Privatklinik Hochrum, Sanatorium der Kreuzschwestern, Rum, Austria
5 Department of Anaesthesiology, Intensive Care Medicine, Emergency Medicine and Pain Therapy, Klinikum Friedrichshafen, Friedrichshafen, Germany

Correspondence Address:
Holger Herff
Department of Anaesthesiology and Intensive Care Medicine, University Hospital of Cologne, Cologne
Germany

In intensive care medicine heat moisture exchangers are standard tools to warm and humidify ventilation gases in order to prevent temperature loss of patients or airway epithelia damage. Despite being at risk of hypothermia especially after trauma, intubated emergency medicine patients are often ventilated with dry and in winter probably cold ventilation gases. We tried to assess the amount of temperature-loss due to ventilation with cold, dry medical oxygen in comparison to ventilation with warm and humidified oxygen. We ventilated a 50-kg water-dummy representing the calorimetric capacity of a 60-kg patient over a period of 2 hours (tidal volume 6.6 mL/kg = 400 mL; respiratory rate 13/min). Our formal null-hypothesis was that there would be no differences in temperature loss in a 50 kg water-dummy between ventilation with dry oxygen at 10°C vs. ventilation with humidified oxygen at 43°C. After 2 hours the temperature in the water-dummy using cold and dry oxygen was 29.7 ± 0.1°C compared to 30.4 ± 0.1°C using warm and humidified oxygen. This difference in cooling rates between both ventilation attempts of 0.7 ± 0.1°C after 2 hours represents an increased cooling rate of ~0.35°C per hour. Ventilation with cool, dry oxygen using an automated transport ventilator resulted in a 0.35°C faster cooling rate per hour than ventilation with warm humidified oxygen in a bench model simulating calorimetric features of a 60-kg human body.


How to cite this article:
Herff H, Schroeder DC, Bowden K, Paal P, Mitterlechner T, Wenzel V. Temperature loss by ventilation in a calorimetric bench model.Med Gas Res 2020;10:27-29


How to cite this URL:
Herff H, Schroeder DC, Bowden K, Paal P, Mitterlechner T, Wenzel V. Temperature loss by ventilation in a calorimetric bench model. Med Gas Res [serial online] 2020 [cited 2020 May 28 ];10:27-29
Available from: http://www.medgasres.com/article.asp?issn=2045-9912;year=2020;volume=10;issue=1;spage=27;epage=29;aulast=Herff;type=0