A prediction model for estimating pulmonary oxygen uptake during the 6-minute walk test in organ transplant recipients.

We developed a multivariate prediction equation for estimating the highest obtainable pulmonary oxygen uptake (VO2p) during the 6-minute walk test (6-MWT) in 54 organ transplant recipients: heart/heart-double-lung (n=14), kidney/kidney-pancreas (n=16), liver (n=14), double lung (n=8), bone marrow (n=2). They were of age, 48+/-12 years. Participants performed a 6-MWT during which expired gases were collected and analyzed with a portable metabolic system interfaced with a wireless heart rate monitor. The following variables significantly contributed to the model for predicting the highest obtainable 6-MWT VO2p: 6-MWT distance (m), age (years), gender (male=0, female=1), resting heart rate, peak heart rate, weight (kg), and transplant type (kidney/kidney-pancreas=1, other=0), where: VO2p=1.253+0.022 (6-MWT distance)+0.112 (age) -3.192 (gender) -0.104 (resting heart rate)+0.127 (peak 6-MWT heart rate)-0.084 (weight)+2.116 (transplant type). The explanatory variables in our final model accounted for 78% of the variance in 6-MWT VO2p. In conclusion, the addition of an easily estimated 6-MWT VO2p will provide added clinical information of functional capacity following an exercise rehabilitation intervention or during routine follow-up for organ transplant recipients.