Aerobic exercise training improves autonomic nervous control in patients with COPD.

Objectives: Autonomic modulation is adversely impacted in patients with chronic obstructive pulmonary disease (COPD). The purpose of the present investigation is to assess the effects of a 6-week aerobic exercise training program on autonomic modulation of heart rate in patients with COPD.

Methods: Forty patients of both sexes with moderate-to-severe COPD were randomly allocated to aerobic exercise training (PT, n=20) or to usual care (Control, n=20).

Non-invasive ventilation improves peripheral oxygen saturation and reduces fatigability of quadriceps in patients with COPD.

Background And Objective: Non-invasive ventilation (NIV) might improve peripheral muscle function and exercise capacity in severely disabled patients. This study evaluated the physiological impact of NIV on isokinetic concentric strength and endurance of lower limb muscles in patients with severe COPD.

Methods: This clinical trial tested COPD patients (n = 24) and healthy subjects (n = 18).

Noninvasive ventilation acutely modifies heart rate variability in chronic obstructive pulmonary disease patients.

Objective: The purpose of present study was to evaluate the acute effects of bi-level positive airway pressure (BiPAP) on heart rate variability (HRV) of stable chronic obstructive pulmonary disease patients (COPD).

Methods: Nineteen males with COPD (69+/-8 years and with forced expiratory volume in 1s <50% of predicted) and eight healthy sedentary age-matched (69 years) males in the control group (CG) were evaluated during two conditions of controlled respiratory rate: spontaneous breathing (SB) and BiPAP (inspiratory and expiratory levels between 12-14 cmH(2)O and 4-6 cmH(2)O, respectively). Peripheral oxygen saturation (SpO(2)), end-tidal of carbon dioxide (ETCO(2)), systolic blood pressure (SBP) and R-R interval were obtained.

Effects of respiratory muscle unloading on leg muscle oxygenation and blood volume during high-intensity exercise in chronic heart failure.

Blood flow requirements of the respiratory muscles (RM) increase markedly during exercise in chronic heart failure (CHF). We reasoned that if the RM could subtract a fraction of the limited cardiac output (QT) from the peripheral muscles, RM unloading would improve locomotor muscle perfusion. Nine patients with CHF (left ventricle ejection fraction = 26 +/- 7%) undertook constant-work rate tests (70-80% peak) receiving proportional assisted ventilation (PAV) or sham ventilation.

Kinetics of muscle deoxygenation are accelerated at the onset of heavy-intensity exercise in patients with COPD: relationship to central cardiovascular dynamics.

Patients with chronic obstructive pulmonary disease (COPD) have slowed pulmonary O(2) uptake (Vo(2)(p)) kinetics during exercise, which may stem from inadequate muscle O(2) delivery. However, it is currently unknown how COPD impacts the dynamic relationship between systemic and microvascular O(2) delivery to uptake during exercise. We tested the hypothesis that, along with slowed Vo(2)(p) kinetics, COPD patients have faster dynamics of muscle deoxygenation, but slower kinetics of cardiac output (Qt) following the onset of heavy-intensity exercise.

Heart rate and arterial pressure variability in the experimental renovascular hypertension model in rats.

This study was conducted in one kidney, one clip (1K1C) Goldblatt hypertensive rats to evaluate vascular and cardiac autonomic control using different approaches: 1) evaluation of the autonomic modulation of heart rate (HR) and systolic arterial pressure (SAP) by means of autoregressive power spectral analysis 2) assessment of the cardiac baroreflex sensitivity; and 3) double blockade with methylatropine and propranolol. The 1K1C group developed hypertension and tachycardia. The 1K1C group also presented reduction in variance as well as in LF (0.

The impact of noninvasive ventilation during the physical training in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD).

Objective: To evaluate the influence of physical training with or without noninvasive ventilation at 2 levels of pressure in the airways (BiPAP) in patients with chronic obstructive pulmonary disease.

Methods: Eighteen patients with FEV(1) = 34 +/- 8% of predicted values, mean age of 68 +/- 9 years were randomly distributed into 2 groups, one group performing physical training on a treadmill and the other group performing physical training associated with BiPAP (physical training+B), for 30 minutes, 3 times a week for 12 weeks. The training velocity was based on a test of cardiopulmonary force performed pre- and postintervention, which registered the values for heart rate, systolic blood pressure, diastolic blood pressure, peripheral oxygen saturation, blood lactate, sensation of dyspnea, respiratory muscle strength, and analysis of gases expired such as oxygen consumption and the production of carbon dioxide.

The influences of positive end expiratory pressure (PEEP) associated with physiotherapy intervention in phase I cardiac rehabilitation.

Purpose: To evaluate the effects of positive end expiratory pressure and physiotherapy intervention during Phase I of cardiac rehabilitation on the behavior of pulmonary function and inspiratory muscle strength in postoperative cardiac surgery.

Methods: A prospective randomized study, in which 24 patients were divided in 2 groups: a group that performed respiratory exercises with positive airway expiratory pressure associated with physiotherapy intervention (GEP, n = 8) and a group that received only the physiotherapy intervention (GPI, n = 16). Pulmonary function was evaluated by spirometry on the preoperative and on the fifth postoperative days; inspiratory muscle strength was measured by maximal inspiratory pressure on the same days.