Improvement in exercise endurance in patients with chronic airflow limitation using continuous positive airway pressure.

To cope with the increased ventilatory demands of exercise, patients with severe expiratory flow limitation adopt strategies that ultimately place greater demands on their inspiratory muscles. Increased inspiratory muscle work may contribute to dyspnea causation and exercise limitation in such patients even before their ventilatory ceiling is attained. In this setting, continuous positive airway pressure (CPAP) should, by favorably affecting inspiratory muscle function and respiratory sensation, improve exercise performance. Six patients with chronic airflow limitation (CAL) (FEV1 +/- SD = 35 +/- 12% predicted) undertook constant-load, submaximal, cycle exercise at 50% of their predetermined maximal oxygen consumption: CPAP of 4 to 5 cm H2O was delivered during one exercise session and bracketed by one or two unassisted control sessions. In four patients, CPAP-assisted (4 to 5 cm H2O) exercise was bracketed by two unassisted control exercise sessions; two remaining patients undertook CPAP-assisted exercise and one unassisted control session. CPAP resulted in a significant increase in exercise endurance time (TLIM) (by 48%: CPAP TLIM (mean +/- SE) = 8.82 +/- 1.90 min; averaged control TLIM = 5.98 +/- 1.23 min (p less than 0.01). CPAP effectively ameliorated exertional dyspnea in the majority of patients; selected dyspnea ratings (Borg scale) during control (final minute) and CPAP at isotime, at comparable levels of ventilation, were (mean +/- SD) 7.83 +/- 2.25 and 5.5 +/- 2.2, respectively (p less than 0.025). Breathing frequency fell significantly during CPAP application (at isotime) by 17% (p less than 0.02); other steady-state ventilatory variables and end-expiratory lung volumes were not significantly different during CPAP and control.(ABSTRACT TRUNCATED AT 250 WORDS)

[1]  M. Younes,et al.  Effect of continuous positive airway pressure on respiratory sensation in patients with chronic obstructive pulmonary disease during submaximal exercise. , 1988, The American review of respiratory disease.

[2]  N. Anthonisen,et al.  Effect of dynamic airway compression on breathing pattern and respiratory sensation in severe chronic obstructive pulmonary disease. , 2015, The American review of respiratory disease.

[3]  N. Anthonisen,et al.  Expiratory resistive loading in patients with severe chronic air-flow limitation. An evaluation of ventilatory mechanics and compensatory responses. , 1987, The American review of respiratory disease.

[4]  M. Younes,et al.  An apparatus for altering the mechanical load of the respiratory system. , 1987, Journal of applied physiology.

[5]  M. Altose,et al.  Mechanisms of dyspnea. , 1987, Clinics in chest medicine.

[6]  N. Jones,et al.  Breathlessness and exercise in patients with cardiorespiratory disease. , 2015, The American review of respiratory disease.

[7]  N. Jones,et al.  Breathlessness during exercise with and without resistive loading. , 1986, Journal of applied physiology.

[8]  L. A. Engel,et al.  Chest wall mechanics during exercise in patients with severe chronic air-flow obstruction. , 1984, The American review of respiratory disease.

[9]  P. Macklem,et al.  The effects of inspiratory muscle training on exercise performance in chronic airflow limitation. , 2015, The American review of respiratory disease.

[10]  A H Morris,et al.  Standardized single breath normal values for carbon monoxide diffusing capacity. , 2015, The American review of respiratory disease.

[11]  M. Belman,et al.  Ventilatory muscle training improves exercise capacity in chronic obstructive pulmonary disease patients. , 2015, The American review of respiratory disease.

[12]  N. Jones,et al.  Pulmonary mechanics during exercise in subjects with chronic airflow obstruction. , 1980, Journal of applied physiology: respiratory, environmental and exercise physiology.

[13]  S. Spiro.  Exercise testing in clinical medicine. , 1977, British journal of diseases of the chest.

[14]  R. Cherniack,et al.  Normal standards for ventilatory function using an automated wedge spirometer. , 1972, The American review of respiratory disease.

[15]  R. Hyatt,et al.  Ventilatory mechanics and expiratory flow limitation during exercise in patients with obstructive lung disease. , 1971, The Journal of clinical investigation.

[16]  H. Levison,et al.  Ventilatory cost of exercise in chronic obstructive pulmonary disease. , 1968, Journal of applied physiology.

[17]  J. Sharp,et al.  The Thorax in Chronic Obstructive Lung Disease , 1968 .

[18]  Goldman Hi,et al.  Respiratory function tests; normal values at median altitudes and the prediction of normal results. , 1959 .