Simple Predictor of Minute Ventilation: Holliday-Segar Revisited

BACKGROUND: Minute ventilation (MV) and calorific requirement (CR) are both functions of metabolic demand. The Holliday-Segar formula is a weight-based tool for predicting CR. This study was performed to derive an equation, based on the Holliday-Segar formula, for calculating resting MV from body-weight (BW), which is applicable for all age groups. METHODS: MV for BW (obtained from Radford normogram) was plotted against CR for BW (as per Holliday-Segar formula), for BWs ranging from neonates to adults. From the scatter plot thus obtained, best-fit line, with the origin as intercept, was drawn. Linear regression analysis was used to obtain R(2) coefficient and P value. RESULTS: The plot of MV against CR yields a straight line passing through the origin with a slope = 46.87. R(2) value is 0.98886, P < 0.001. CONCLUSION: MV can be easily and reliably estimated for all age groups from the equation: MV (mL/min) = 47 × CR (kcal/h).