Abnormal Exercise Responses in Survivors of Acute Lung Injury During Cardiopulmonary Exercise Testing: AN OBSERVATIONAL STUDY.

ABSTRACT

PURPOSE: This study compared exercise responses in individuals who had recently survived an admission to the intensive care unit for acute lung injury (ALI) with healthy controls. METHODS: Ten patients with ALI were recruited at 2 Australian hospitals. Six weeks after hospital discharge, participants completed lung function measures and a laboratory-based cardiopulmonary exercise test. Identical measures were collected in 21 healthy participants of similar age and gender distribution. RESULTS: Compared with the healthy participants, the ALI participants were similar in age (51 ± 14 vs 50 ± 16 yr), with a lower peak oxygen uptake ((Equation is included in full-text article.)O2) (median [interquartile range], 31.80 [26.60-41.73] vs 17.80 [14.85-20.85] mL/kg/min; P < .01) and higher ventilatory equivalent for carbon dioxide ((Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2) at anaerobic threshold (mean ± SD, 25.7 ± 2.5 vs 35.2 ± 4.1; P < .01). Analysis of individual ALI participant responses showed that 8 participants had a decreased peak (Equation is included in full-text article.)O2 and anaerobic threshold. All ALI participants were limited by leg fatigue. Abnormalities of pulmonary gas exchange were present in 7 participants. Evidence of cardiac ischemia was present in 2 participants. CONCLUSIONS: Compared with healthy controls, ALI participants had reduced exercise capacity, mainly due to profound deconditioning. Exercise training to optimize aerobic capacity would appear to be a rehabilitation priority in this population.