Do Handheld Calorimeters Have a Role in Assessment of Nutrition Needs in Hospitalized Patients?

Abstract

Indirect calorimetry is a noninvasive and reliable means of determining resting metabolic rate in humans. Barriers to obtaining an accurate measure of resting metabolic rate (RMR) in hospitalized patients include the expense and the requirement of technical expertise for maintenance. A literature search on handheld calorimeters was conducted using PubMed and OVID. The search resulted in a total of 54 published articles; 23 of these specifically are about handheld calorimeter devices. Results from a handheld calorimeter were similar to those obtained from metabolic cart studies. The Douglas bag method compared with the MedGem indicated a significant agreement (P = .286). The handheld device was compared with metabolic carts in 9 studies with mixed results. The predictive equations (Harris-Benedict, Mifflin-St Jeor, and FAO/WHO equations) over- and underestimated RMR compared with the MedGem. The Harris-Benedict equation overestimated the RMR by 3%-11%, the Mifflin-St Jeor equation overestimated the RMR by 1%, and the FAO/WHO equation overestimated RMR by 12%. The present study examines the validity and reliability of handheld calorimeters for measuring resting energy expenditure based on published literature. Handheld calorimeters are more accurate than predictive equations based on gender, age, and ethnicity for determining resting metabolic rate and are therefore a viable alternative for clinical evaluation of the hospitalized patient.