Effect of Maximal Oxygen Pulse on Patients with Chronic Obstructive Pulmonary Disease

This study evaluated the effect of maximal oxygen pulse (O ₂P _max) on patients with chronic obstructive pulmonary disease (COPD) and confirmed the predictive effect on acute exacerbations of COPD (AECOPD).

This retrospective study included 91 participants who underwent cardiopulmonary exercise testing (CPET), lung function testing, a dyspnea scale assessment, and a 3-year follow-up. The participants were divided into two groups according to the O ₂P _max value. Exercise capacity, ventilatory conditions, gas exchange efficiency, and dyspnea symptoms were compared, and the correlations between O ₂P _max and these indices were evaluated. The ability of O ₂P _max to predict AECOPD was examined.

Exercise capacity, ventilatory conditions, and gas exchange efficiency were lower, and dyspnea symptom scores were higher in the impaired O ₂P _max group ( P < 0.05). O ₂P _max was positively correlated with forced vital capacity (FVC)%, forced expiratory volume in 1 sec (FEV ₁)%, FEV ₁/FVC%, anaerobic threshold (AT), work rate (WR)%, aximal oxygen uptake (V̇O _2max)%, V̇O ₂/kg _max, V̇O ₂/kg _max%, WR _AT, WR _max, V̇O _2AT, V̇O _2max, and V̇ _Emax, and was negatively correlated with EqCO _2AT, and EqCO _2max ( P < 0.05). Most importantly, O ₂P _max could be used to predict AECOPD, and the best cut-off value was 89.5% (area under the curve, 0.739; 95% CI, 0.609-0.869).

O ₂P _max reflected exercise capacity, ventilation capacity, gas exchange capacity, and dyspnea symptoms in patients with COPD and may be an independent predictor of AECOPD.