Regional and Total Lung Function Studies in Patients with Hemidiaphragmatic Paralysis

Abstract

Global and regional lung function were studied in 17 subjects with hemidiaphragmatic paralysis. Global lung function (VC, MVV, and FEV1) in the sitting position was reduced by an average of about 25 %. Regional lung function data in the same position showed a considerable decrease in perfusion (19%), ventilation (20%), and lung volume (7%) of the diseased side as compared to reference values obtained in healthy volunteers. Compared to the partition of function in the supine, the perfusion of the affected lung increased when it was lowermost in the lateral decubitus position, while regional FRC decreased and ventilation changed little. When uppermost, perfusion and ventilation of the affected lung decreased while FRC_r·increased somewhat. The arterial oxygen tension was significantly below normal in the supine position but in the normal range in the sitting position. It increased further during exercise. Bronchography showed compression of the basal lung segments on the affected side in the erect, and kinking and obliteration of lower lobe bronchi in the supine position and still more when the lung was lowermost in the lateral decubitus position.

Effect of posture on lung volume: airway closure and gas exchange in hemidiaphragmatic paralysis.

“…Arborelius et al (1975) showed the reduction to be least prominent supine and greatest sitting. However, the reduction in perfusion (19%) and ventilation (20%) in the sitting posture tended to be better matched than in the supine posture when perfusion was reduced by 9% and ventilation by 14%.…”

“…Orthopnoea is a prominent symptom in many patients with diaphragmatic paralysis (McCredie et al, 1962) and hypoxia has also been observed in these patients when recumbent (Arborelius et al, 1975). We have examined airway closure in relation to this hypoxia and also studied the positional changes in overall lung function in hemidiaphragmatic paralysis unassociated with intrathoracic disease.…”

Regional lung function in unilateral diaphragmatic paralysis.

“…These patients were free of symptoms. Arborelius et al (1975) studied 17 patients with a paralysed hemidiaphragm and found a mean vital capacity in the sitting position of 74-6% predicted and total lung capacity of 86-1 % predicted; however, in more than half these patients the paralysis had followed thoracotomy.…”

“…The distribution in the opposite lung did not differ significantly from that found in normal subjects although the proportion of inhaled xenon reaching the lung base was rather less than in the normal group. The washout of injected xenon was norinal except for slight impairment at the lung base on the paralysed side in one patient and at both bases in another.So far as we are aware, the only previous account of regional lung function in diaphragmatic paralysis is the recent report by Arborelius, Lilja, and Senyk (1975). These authors studied 17 patients in various postures.…”

“…So far as we are aware, the only previous account of regional lung function in diaphragmatic paralysis is the recent report by Arborelius, Lilja, and Senyk (1975). These authors studied 17 patients in various postures.…”