G: Increased oxygen pulse after lung volume reduction surgery is associated with reduced dynamic hyperinflation

ABSTRACT: Stroke volume augmentation during exercise is limited in chronic obstructive pulmonary disease patients because of decreased preload from dynamic hyperinflation (DH). We hypothesised that oxygen pulse and pulse pressure (PP) improve following lung volume reduction surgery (LVRS), and the magnitude of improvement correlates with reduction in DH. We compared 16 emphysema patients undergoing LVRS with six emphysema patients not undergoing LVRS. Oxygen pulse and PP were calculated from maximal cardiopulmonary exercise tests at baseline and 6 months. End-expiratory lung volume (EELV)/total lung capacity (TLC) represented DH. Comparisons were made between baseline and 6 months at metabolic isotimes (per cent maximal carbon dioxide production (V9CO 2 ,max)). At baseline, the LVRS group was older with higher forced expiratory volume in 1 s, but had similar hyperinflation to the non-LVRS group. At 6 months, oxygen pulse (50%, 75%, and 100% V9CO 2 ,max) and PP (50% and 75% V9CO 2 ,max) increased in the LVRS, but not in the non-LVRS group. Baseline functional residual capacity/TLC inversely correlated with resting oxygen pulse (r5 -0.449, p50.04). Decreased EELV/TLC correlated with increased oxygen pulse at 75% (r5 -0.487, p50.02) and 100% V9CO 2 ,max (r5 -0.548, p50.008). LVRS led to increased oxygen pulse and PP during exercise at metabolic isotimes 6 months following surgery. Reductions in DH correlated with increases in oxygen pulse during exercise. Reducing lung volume may improve stroke volume response to exercise by decreasing DH. KEYWORDS: Cardiopulmonary interactions, chronic obstructive pulmonary disease, exercise, physiology C hronic obstructive pulmonary disease (COPD) patients have impaired exercise tolerance, which limits their quality of life. While ventilatory limitations, including dynamic hyperinflation (DH), are the main cause of exercise intolerance in this population [1], causes for this impairment are probably multifactorial Along with its beneficial effects on mortality To investigate the effect of DH and LVRS on cardiac performance during exercise, we retrospectively analysed data from emphysema patients who had cardiopulmonary exercise tests (CPETs) before and after LVRS, and compared their changes with those who did not undergo LVRS. We hypothesised that LVRS would lead to an increase in non-invasive markers of stroke volume (oxygen puls

Determinants of CPAP Adherence in Hispanics with Obstructive Sleep Apnea

Purpose. We hypothesized that socioeconomic factors and a language barrier would impact adherence with continuous positive airway pressure (CPAP) among Hispanics with obstructive sleep apnea (OSA). Methods. Patients with OSA who were prescribed CPAP for at least 1 year and completed a questionnaire evaluating demographic data, socioeconomic status, and CPAP knowledge and adherence participated in the study. Results. Seventy-nine patients (26 males; 53±11 yrs; body mass index (BMI)=45±9 kg/m2) with apnea-hypopnea index (AHI) 33±30 events/hr completed the study. Included were 25 Hispanics, 39 African Americans, and 15 Caucasians, with no difference in age, AHI, CPAP use, or BMI between the groups. While there was a difference in educational level (P=0.006), income level (P<0.001), and employment status (P=0.03) between the groups, these did not influence CPAP adherence. Instead, overall improvement in quality of life and health status and perceived benefit from CPAP influenced adherence, both for the group as a whole (P=0.03, P=0.004, and P=0.001, resp.), as well as in Hispanics (P=0.02, P=0.02, P=0.03, resp.). Conclusion. In Hispanic patients with OSA, perceived benefit with therapy, rather than socioeconomic status or a language barrier, appears to be the most important factor in determining CPAP adherence

Supplemental material for Changes in hemodynamic classification over time are common in systemic sclerosis-associated pulmonary hypertension: insights from the PHAROS cohort

<p>Supplemental material, for Changes in hemodynamic classification over time are common in systemic sclerosis-associated pulmonary hypertension: insights from the PHAROS cohort by Matthew R. Lammi, Lesley Ann Saketkoo, Jessica K. Gordon and Virginia D. Steen in Pulmonary Circulation</p

Air Current Applied to the Face Improves Exercise Performance in Patients with COPD

Purpose: Improving dyspnea and exercise performance are goals of COPD therapy. We tested the hypothesis that air current applied to the face would lessen dyspnea and improve exercise performance in moderate-severe COPD patients.Methods: We recruited 10 COPD patients (5 men, age 62 ± 6 years, FEV1 0.93 ± 0.11 L (34 ± 3 % predicted), TLC 107 ± 6 %, RV 172 ± 18 %) naïve to the study hypothesis. Each patient was randomized in a crossover fashion to lower extremity ergometry at constant submaximal workload with a 12-diameter fan directed at the patients face or exposed leg. Each patients\u27 studies were separated by at least 1 week. Inspiratory capacity and Borg dyspnea score were measured every 2 min and at maximal exercise.Results: Total exercise time was longer when the fan was directed to the face (14.3 ± 12 vs. 9.4 ± 7.6 min, face vs. leg, respectively, p = 0.03). Inspiratory capacity tended to be greater with the fan directed to the face (1.4 (0.6-3.25) vs. 1.26 (0.56-2.89) L, p = 0.06). There was a reduction in dynamic hyperinflation, as reflected by higher IRV area in the fan on face group (553 ± 562 a.u. vs. 328 ± 319 a.u., p = 0.047). There was a significant improvement in the Borg dyspnea score at maximal exercise (5.0 (0-10) vs. 6.5 (0-10), p = 0.03), despite exercising for 34 % longer with the fan directed to the face.Conclusions: Air current applied to the face improves exercise performance in COPD. Possible mechanisms include an alteration in breathing pattern that diminishes development of dynamic hyperinflation or to a change in perception of breathlessness

Macitentan in Pulmonary Arterial Hypertension Associated with Connective Tissue Disease (CTD-PAH): Real-World Evidence from the Combined OPUS/OrPHeUS Dataset

The above graphical abstract represents the opinions of the authors. For a full list of declarations, including funding and author disclosure statements, and copyright information, please see the full text online. (see “read the peer-reviewed publication” opposite). </p