RT Journal Article
SR Electronic
T1 Maximum Voluntary Ventilation in a Population Residing at 2,240 Meters Above Sea Level
JF Respiratory Care
FD American Association for Respiratory Care
SP 1588
OP 1593
DO 10.4187/respcare.04939
VO 62
IS 12
A1 Silvia Cid-Juárez
A1 Rogelio Pérez-Padilla
A1 Luis Torre-Bouscoulet
A1 Paul Enright
A1 Laura Gochicoa-Rangel
A1 Daniel Cortés-Medina
A1 Peter Eliud Bapo-López
A1 Marco Vinicio Tafolla-Manzo
A1 Sergio Manuel Grave Díaz
YR 2017
UL http://rc.rcjournal.com/content/62/12/1588.abstract
AB BACKGROUND: Measured maximum voluntary ventilation (MVV) correlates with maximum ventilatory capacity during exercise. As a shortcut, MVV is often estimated by multiplying measured FEV1 times 35 or 40, but this index varies with altitude due to reduced air density. The objective was to describe MVV in healthy individuals residing at 2,240 m above sea level and compare it with the reference values customarily employed.METHODS: We recruited a convenience sample of respiratory-healthy, non-obese volunteers >10 y of age who had resided for >2 y in Mexico City. All participants performed forced spirometry and MVV according to current standards. Multiple regression models were fitted, including age, height, and measured FEV1, separately for males and females to obtain reference values. The impact of lower air density on MVV at this elevation was estimated from the reported increase in peak flow in relation to altitude.RESULTS: We studied 381 individuals (210 females [55.1%]) age 10–80 y with a mean MVV of 145.6 ± 48 L/min. Both FEV1 × 35 and FEV1 × 40 underestimated the MVV observed: in males by approximately 26% and in females by approximately 10%. MVV for our population approached FEV1 × 45 (98 ± 15.6% of real MVV). Multiple regression models including height, weight, and measured FEV1 explained 70% of residual variability once sex was taken into account.CONCLUSIONS: At an altitude of 2,240 m, MVV is about 45 times the measured FEV1, and it can be estimated for other altitudes. The best predicting equations for MVV were calculated separately for females and males and included the following predictors: age, age2, and measured FEV1. The study found that reference values for MVV from studies conducted at sea level are inaccurate at this altitude.