How does the Reevue measure metabolic rate?

The human body consumes a fixed amount of oxygen per calorie burned. The Reevue  measures the amount of oxygen the patient's body is consuming. Based on the measured oxygen consumption rate, the Reevue then calculates the Resting Energy Expenditure (REE). Or, in other words, exact amount of calories that person is burning.

What are the steps of a Reevue test?

The Reevue automatically calibrates itself, so there is no need to configure the unit prior to each test. First, ask the patient to relax in a seated or reclining position. The patient then breathes into a mask or mouthpiece for about 10 minutes. When the test is complete, the Reevue prints a detailed report of the results. Perhaps the simplest indirect calorimeter ever built!

What is the difference between BMR and resting metabolic rate (RMR)?

BMR stands for Basal Metabolic Rate. BMR is a Resting Energy Expenditure test with a strict protocol to prepare the patient for the test. Therefore, the results from the Reevue can be interpreted as BMR if the protocol is followed. The protocol has requirements regarding sleep, exercise, and fasting prior to the test, and temperature and lighting during the test.

What is the difference between REE and RMR?

These terms are essentially the same. REE stands for Resting Energy Expenditure. RMR stands for Resting Metabolic Rate. Both indicate the amount of energy a person burns at rest, and can be used interchangeably.

What kind of patient connection does Reevue require?

Reevue can be used with a disposable mouthpiece or a disposable mask. It uses standard respiratory fittings to accommodate a variety of hoses and reusable masks.

Indirect Calorimetry

There are various methods of measuring and estimating caloric burn rate energy expenditure. Estimating energy expenditure is usually done using equations such as the Harris-Benedict equation. Other estimation techniques may make use of directly measured percent body fat, heart rate, etc. The only methods of directly measuring energy expenditure are doubly labeled water (DLW) and indirect calorimetry (IC). The doubly labeled water technique is primarily a laboratory-based research method in which energy expenditure is calculated from carbon dioxide production measured over a multiple day period.

Indirect calorimetry is the only accurate and clinically feasible method of measuring energy expenditure. It is called “indirect” because the caloric burn rate is calculated from a measurement of oxygen uptake. Direct calorimetry implies a measurement of heat released by the body, which is technically difficult and clinically impractical.

Indirect calorimetry relies on the fact that burning 1 calorie (Kilocalorie) requires 208.06 milliliters of oxygen. Because of this very direct relationship between caloric burn and oxygen consumed, measurements of oxygen uptake (VO2) and caloric burn rate are virtually interchangeable. Oxygen uptake requires a precise measurement of the volume of expired air and of the concentration of oxygen in the expired air.