Standardized exercise oximetry predicts postpneumonectomy outcome

Abstract

We have developed a safe, simple, and easily performed standardized exercise oximetry outpatient test to assess patients undergoing lung resections. We studied its ability to predict outcome after pneumonectomy in 46 consecutive patients over a 5-year period. Room air oximetry is initially performed at rest. The patient then begins to exercise on a stair-stepper apparatus (Stamina Stepper), which provides uniform resistance to stepping. Oxygen saturation values are noted at 10, 20, and 30 steps, equivalent to climbing three flights of stairs. Group 1 consisted of the patients who either had a resting saturation less than 90%, or desaturation greater than or equal to 4% during exercise. Group 2 consisted of all patients who had a preoperative forced expiratory volume in 1 second of 60% or less. Group 3 consisted of all patients who had a predicted postoperative forced expiratory volume in 1 second of 40% or less. Group 4 consisted of patients who had a predicted postoperative diffusing capacity of 40% or less. There were four deaths (8.6%), 12 patients (26%) remained in the intensive care unit 4 or more days, and 11 patients (23%) suffered major morbidity. Desaturation during exercise (group 1) significantly predicted longer intensive care unit stay (p = 0.0002) and incidence of major morbidity (p < 0.0001). Groups 2, 3, and 4 were not significantly predictive of either longer intensive care unit stay or major morbidity. Standardized exercise oximetry performed in the outpatient facility is highly predictive of major morbidity and prolonged intensive care unit stay after pneumonectomy.