ABSTRACT
Breathing pattern, respiratory activity and respiratory muscle function were studied in 25 patients with schistosomal cor pulmonale, with mean pulmonary artery pressure [MPAP] of 47.4 +/- 21.2 mmHg, cardiac index 3.2 +/- 0.5 L/min/m2 and pulmonary vascular resistance [PVR] 7.4 +/- 4.4 units. The pattern of breathing showed near normal tidal volume, increased respiratory frequency, minute ventilation, mean inspiratory flow and decreased inspiratory duty cycle. Respiratory center activity, as measured by the mouth occlusion pressure P 0.1, was increased and demonstrated significant positive correlation with the mean pulmonary artery pressure. Data of the present study also revealed that schistosomal cor pulmonale patients have respiratory muscle weakness as evidenced by a reduction in the maximal inspiratory and expiratory pressure, while diaphragmatic function was found to be preserved. The respiratory muscle strength [PI max and PE max] revealed strong negative correlation with MPAP and PVR. Inclusion schistosomal cor pulmonary patients exhibit disturbed breathing pattern and respiratory muscle performance. The study of these parameters should be included in evaluating ventilatory function in such patients, since it reflects changes in pulmonary hemodynamics