Development of a Portable Respiratory Gas Analyzer for Measuring Indirect Resting Energy Expenditure (REE)

Figure 1

Functional diagram of the respiratory gas analyzer. The flow velocity of the exhaled gas is measured on the mask, and some of it (5%∼10%) is collected using a DC motor. Since the vapor in the collected exhaled gas affects the measurement, the partial pressure of oxygen and carbon dioxide is measured after water is removed using a water trap.