Postural relief of dyspnoea in severe chronic airflow limitation: relationship to respiratory muscle strength.

Maximal static inspiratory and expiratory pressures (Pimax and Pemax) were measured in six different positions in 40 patients with advanced chronic airflow limitation and in 140 normal subjects to determine whether posture influences respiratory muscle strength. Patients with chronic airflow limitation were studied on days 1 and 5 of an acute exacerbation. There was no postural effect on maximal static pressures in the normal subjects. We divided our patients with chronic airflow limitation into "moderate" and "severe" groups on the basis of a Pimax in the standing position greater or less than 35 cm H2O. The seated leaning-forward position was the preferred posture in 22 of the 23 "severe" patients and 13 of the 17 "moderate" patients. Pimax was greater in the seated leaning-forward position than in the other positions studied (p less than 0.001) on days 1 and 5 in the "severe" patients and (p less than 0.05) on day 5 in the "moderate" patients. Posture had no influence on Pemax in patients with chronic airflow limitation. There was a significant improvement in both Pimax (p less than 0.01 for the "severe" group and p less than 0.05 for the "moderate" group) and Pemax (p less than 0.01 for both groups) between days 1 and 5. The seated leaning-forward position was the optimum posture for the patients to generate maximum inspiratory pressures and to obtain greatest subjective relief of dyspnoea.

[1]  D. F. Rochester,et al.  Respiratory muscle strength and maximal voluntary ventilation in undernourished patients. , 2015, The American review of respiratory disease.

[2]  F. Mastaglia,et al.  Respiratory muscle function and ventilatory control. I in patients with motor neurone disease. II in patients with myotonic dystrophy. , 1982, The Quarterly journal of medicine.

[3]  R M Gardner,et al.  Reference spirometric values using techniques and equipment that meet ATS recommendations. , 2015, The American review of respiratory disease.

[4]  J. Sharp,et al.  Postural relief of dyspnea in severe chronic obstructive pulmonary disease. , 2015, The American review of respiratory disease.

[5]  R. Greenspan.  PRINCIPLES OF CHEST X-RAY DIAGNOSIS (4th ed) , 1979 .

[6]  D. F. Rochester,et al.  Respiratory muscle strength in chronic obstructive pulmonary disease. , 1979, The American review of respiratory disease.

[7]  Barach Al.  Chronic obstructive lung disease: postural relief of dyspnea. , 1974, Archives of Physical Medicine and Rehabilitation.

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

[9]  R. Edwards,et al.  Clinical and physiological associations of some physical signs observed in patients with chronic airways obstruction , 1970, Thorax.

[10]  L. F. Black,et al.  Maximal respiratory pressures: normal values and relationship to age and sex. , 2015 .

[11]  E J Campbell,et al.  Physical signs of diffuse airways obstruction and lung distension , 1969, Thorax.

[12]  T. Ringqvist.  The ventilatory capacity in healthy subjects. An analysis of causal factors with special reference to the respiratory forces. , 1966, Scandinavian journal of clinical and laboratory investigation. Supplementum.

[13]  P. Armitage,et al.  OBSERVER DISAGREEMENT IN PHYSICAL SIGNS OF THE RESPIRATORY SYSTEM. , 1965, Lancet.

[14]  NEW height-weight tables. Importance of new criteria. , 1960, JAMA.

[15]  M. Daves.  Principles of Chest X-ray Diagnosis , 1957 .

[16]  J. H. Comroe,et al.  A rapid plethysmographic method for measuring thoracic gas volume: a comparison with a nitrogen washout method for measuring functional residual capacity in normal subjects. , 1956, The Journal of clinical investigation.

[17]  A. Barach,et al.  The ventilatory effects of the head-down position in pulmonary emphysema. , 1954, The American journal of medicine.