Arterial baroreflex function is altered by dynamic exercise, but it is not clear to what extent baroreflex changes are due to altered transduction of pressure into deformation of the barosensory vessel wall. In this study we measured changes in mean common carotid artery diameter and the pulsatile pressure : diameter ratio (PDR) during and after dynamic exercise. Ten young, healthy subjects performed a graded exercise protocol to exhaustion on a bicycle ergometer. Carotid dimensions were measured with an ultrasound wall-tracking system; central arterial pressure was measured with the use of radial tonometry and the generalized transfer function; baroreflex sensitivity (BRS) was assessed in the post-exercise period by spectral analysis and the sequence method. Data are given as means ± S.E.M. Mean carotid artery diameter increased during exercise as compared with control levels, but carotid distension amplitude did not change. PDR was reduced from 27.3 ± 2.7 to 13.7 ± 1.0 mm mmHg _1 . Immediately after stopping exercise, the carotid artery constricted and PDR remained reduced. At 60 min post-exercise, the carotid artery dilated and the PDR increased above control levels (33.9 ± 1.4 mm mmHg _1 ). The post-exercise changes in PDR were closely paralleled by those in BRS (0.74 ≤ r ≤ 0.83, P < 0.05). These changes in mean carotid diameter and PDR suggest that the mean baroreceptor activity level increases during exercise, with reduced dynamic sensitivity; at the end of exercise baroreceptors are suddenly unloaded, then at 1 h post-exercise, baroreceptor activity increases again with increasing dynamic sensitivity. The close correlation between PDR and BRS observed at post-exercise underlies the significance of mechanical factors in arterial baroreflex control.
Background: The role of pre-and post-lung transplant rehabilitation is to maintain or improve exercise tolerance, lung mechanics, peripheral and respiratory muscle function. Our aim was to measure the effectiveness of pre-and post-transplant rehabilitation in terms of the changes of functional and quality of life markers. Methods: Sixty-three patients (40 COPD FEV1: 21±5 %pred, 18 IPF TLC: 42±13 %pred, 4 bronchiectasis FEV1: 28±4 %pred and 1 alveolitis fibrotisans TLC: 31 %pred) participated in a pre-and 14 took part in a post-transplant rehabilitation program (more than 2 months after lung transplantation (LTx), primary diagnoses: 9 COPD, 4 IPF). The rehabilitation program consisted of chest-wall stretching, controlled breathing techniques and personalized exercise of 20-30 minutes by cycling and treadmill 2-3 times per day for 4 weeks. Seven functional and quality of life markers, like lung function, chest wall expansion (CWE), 6-minute walking distance (6MWD), modified Medical Research Council Dyspnea Scale (mMRC), COPD Assessment Test (CAT), breath holding time (BHT) and hand grip strength (HGS) were measured at the onset and the end of the rehabilitation program. The safety profile of the rehabilitation program was followed-up. Results: Pre-transplant pulmonary rehabilitation resulted in significant improvement in CWE (3.24±1.49 vs. 4.48±1.62 cm), CAT IQR {19 [13-25] vs. 15 [11-21]}, 6MWD (315±118 vs. 375±114 m), P<0.05. FEV1, FVC, mMRC, BHT and HGS did not change significantly. Post-transplant rehabilitation resulted in significant improvement in CWE (3.7±2.1 vs. 6.2±1.8 cm), CAT IQR {17 [11-23] vs. 10 [6-14], BHT (22±14 vs. 35±16 s), FEV1 (73±8 vs. 86±9 %pred) and FVC (70±12 vs. 85±14 %pred), P<0.05. The 6MWD, mMRC and HGS did not change significantly. No cardiovascular or other side effects were detected during the rehabilitation program.Conclusions: Our results underline the importance of perioperative pulmonary rehabilitation in the complex treatment of lung transplant patients in Hungary, as well. There was a limitation because no control group was evaluated without rehabilitation.
The choice of inhaler device for bronchodilator reversibility is crucial since suboptimal inhalation technique may influence the result. On the other hand, bronchodilator response also varies from time to time and may depend on patient characteristics. In this study, patients with airway obstruction (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] ratio <70% in chronic obstructive pulmonary disease [COPD]; <80% in asthma) were included (n=121, age: 57.8±17.3 years). Bronchodilator reversibility (American Thoracic Society/European Respiratory Society criteria) was tested in patients with COPD (n=63) and asthma and COPD overlap syndrome (ACOS; n=12). Forty-six asthmatics served as controls. Reversibility was tested with 400 µg salbutamol dry powder inhaler (Buventol Easyhaler, Orion Pharma Ltd, Espoo, Finland). Demographic data and patients’ perceptions of Easyhaler compared with β2-agonist pressurized metered dose inhalers (pMDIs) were analyzed. American Thoracic Society/European Respiratory Society guideline defined reversibility was found in 21 out of 63 COPD patients and in two out of 12 ACOS patients. Airway obstruction was more severe in COPD patients as compared with controls (mean FEV1 and FEV1% predicted both P<0.0001). Average response to salbutamol was significantly lower in COPD patients compared with asthma controls (P<0.0001). Reversibility was equally often found in smokers as in never-smokers (33% vs 34%). Nonreversible COPD patients had higher mean weight, body mass index, and FEV1/FVC compared with reversible COPD patients. Most patients preferred Easyhaler and defined its use as simpler and more effective than use of a pMDI. Never-smokers and patients with asthma experienced Easy-haler somewhat easier to use than smokers and patients with COPD. In conclusion, a substantial part of patients with COPD or ACOS showed reversibility to salbutamol dry powder inhaler. Nonreversible patients with COPD were characterized by higher weight and body mass index, and a higher FEV1/FVC ratio. Most patients preferred Easyhaler compared with a pMDI.
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