Jochen Hinkelbein1, Eckard Glaser, Janine Doerrstein, Harald V Genzwuerker. 1. University Clinic for Anesthesiology and Intensive Care Medicine, Faculty for Clinical Medicine Mannheim, Ruprecht-Karls-University of Heidelberg, University Hospital Mannheim, Germany. jochen.hinkelbein@anaes.ma.uni-heidelberg.de
Abstract
OBJECTIVE: Differences in mask design may alter the oxygen flow required to gain similar oxygenation at a particular altitude. The selection of the most efficient mask would be advantageous for general aviation and other applications where oxygen supply is limited. METHODS: We compared a basic mask (BAS) without valves or oxygen reservoir bag to a test mask (TST) with three valves and a reservoir designed to deliver up to 80% oxygen for critically ill patients. Randomly assigned parachutists (n = 31) used the masks during a flight with a gradual climb to 6863 m (22,500 ft). The oxygen flow was individually controlled to produce oxygen saturation (SpO2) of 95-97% as determined by pulse oximetry. Oxygen flow and SpO2 were obtained every 305 m (1000 ft). RESULTS:Baseline age, lung function indices, and SpO2 were comparable for the two groups. Mean in-flight Spo2 values were 95.3 +/- 0.5% for the BAS and 96.2 +/- 1.1 % for the TST, respectively. Above 3965 m (13,000 ft) the TST required significantly less oxygen flow than the BAS to maintain the target SpO2. At 6863 m (22,500 ft), mean oxygen flow was 5.5 +/- 3.5 L x min(-1) for the BAS vs. 3.4 +/- 2.3 L x min(-1) for the TST (p = 0.029). No adverse reactions were reported from either group. CONCLUSION: The TST required significantly less oxygen flow compared with the BAS at high altitudes and may, therefore, reduce total oxygen use, resulting in reduced costs and longer oxygen availability during a flight.
RCT Entities:
OBJECTIVE: Differences in mask design may alter the oxygen flow required to gain similar oxygenation at a particular altitude. The selection of the most efficient mask would be advantageous for general aviation and other applications where oxygen supply is limited. METHODS: We compared a basic mask (BAS) without valves or oxygen reservoir bag to a test mask (TST) with three valves and a reservoir designed to deliver up to 80% oxygen for critically illpatients. Randomly assigned parachutists (n = 31) used the masks during a flight with a gradual climb to 6863 m (22,500 ft). The oxygen flow was individually controlled to produce oxygen saturation (SpO2) of 95-97% as determined by pulse oximetry. Oxygen flow and SpO2 were obtained every 305 m (1000 ft). RESULTS: Baseline age, lung function indices, and SpO2 were comparable for the two groups. Mean in-flight Spo2 values were 95.3 +/- 0.5% for the BAS and 96.2 +/- 1.1 % for the TST, respectively. Above 3965 m (13,000 ft) the TST required significantly less oxygen flow than the BAS to maintain the target SpO2. At 6863 m (22,500 ft), mean oxygen flow was 5.5 +/- 3.5 L x min(-1) for the BAS vs. 3.4 +/- 2.3 L x min(-1) for the TST (p = 0.029). No adverse reactions were reported from either group. CONCLUSION: The TST required significantly less oxygen flow compared with the BAS at high altitudes and may, therefore, reduce total oxygen use, resulting in reduced costs and longer oxygen availability during a flight.
Authors: Jochen Hinkelbein; Lennert Böhm; Stefan Braunecker; Harald V Genzwürker; Steffen Kalina; Fabrizio Cirillo; Matthieu Komorowski; Andreas Hohn; Jörg Siedenburg; Michael Bernhard; Ilse Janicke; Christoph Adler; Stefanie Jansen; Eckard Glaser; Pawel Krawczyk; Mirko Miesen; Janusz Andres; Edoardo De Robertis; Christopher Neuhaus Journal: Intern Emerg Med Date: 2018-05-05 Impact factor: 3.397