RT Journal Article SR Electronic T1 Factors predicting exercise-induced oxygen desaturation in stable COPD JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP P839 VO 40 IS Suppl 56 A1 Khaled Hussein A1 Atef Farouk Alkarn A1 Samiaa Hamdi A1 Raafat El-Sokkary A1 Hamdy Shams YR 2012 UL http://erj.ersjournals.com/content/40/Suppl_56/P839.abstract AB Background and objective:-Some resting pulmonary function and blood gas parameters might predict exercise-induced oxygen desaturation in patients with stable COPD. We aimed at studying these factors.Patients and methods:-We tested 55 patients with stable COPD (FEV1/FVC%: 54.31).Resting pulmonary function, arterial blood gases, echocardiography, and incremental cardiopulmonary exercise testing were done for all patients. We diagnosed exercise-induced oxygen desaturation if O2 saturation decreased ≥ 4% with exercise. We compared desaturated (DS) with non-desaturated (NDS) patients.Results:-Exercise induced oxygen desaturation (DS) occurred in 28 subjects while 27 were non-desaturated (NDS). FEV1% of predicted was significantly lower in DS (33.75±9.28) than NDS patients (49.49±19.86, P<0.001). Diffusing capacity DLCO % predicted was significantly lower in DS (47.54±20.25) than NDS (67.35±19.62, P<0.001). Resting O2 saturation SaO2 % was significantly lower in DS (91.9±2.88) than NDS patients (95.94±2.9, P<0.001). Resting PaCO2 mmHg was significantly higher in DS (63.46±11.58) than NDS patients (38.97±6.38, P<0.001). Pulmonary artery systolic pressure mmHg was significantly higher in DS (42.21±11.90) than NDS (34.15±12.14, P< 0.01). Medical Research Council MRC dyspnea score was significantly higher in DS (3.54±0.69) than NDS patients (2.44±0.97, P<0.001). On the other hand, there were no statistically significant differences in FEV1/FVC%, total lung capacity, residual volume, and resting heart rate between the DS and NDS patients.Conclusion:-FEV1%, DLCO, resting SaO2, resting PaCO2, pulmonary artery systolic pressure and MRC dyspnea score can predict exercise-induced desaturation in stable COPD.