New Advanced Mass Casualty Breathing System for Oxygen Therapy: Phase 1

This report describes the first phase of a project to develop an efficient mass casualty oxygen O2 breathing system for O2 therapy in remote areas. In this first phase, DRDC Toronto was tasked to investigate the performance of the Pulmanex Hi-Ox mask Hi-Ox at O2 flow rates from 4 litres per minute L min-1 down to 0.5 L min-1. Performance was evaluated with eighteen male and female volunteers between the ages of 21 and 56 years. Subjects were at rest in a seated position. The data showed that it is possible to use the Hi-Ox for O2 treatment with low flow rates. The peak concentration of inhaled oxygen was 31.7 5.6 at 0.5 L min-1 and 80.3 7.8 at 4 L min-1. To achieve a given level of O2 concentration, the Hi-Ox required significantly less O2 than the commonly used simple facemask. This will allow the use of portable O2 concentrators to supply oxygen to the Hi-Ox, increasing the efficiency and minimizing risks.