The Degree of Relaxation Obtained in Different Diameters of the Lung By Pneumoperitoneum and Phrenic Paralysis, When Used Either Singly or in Combination

1. A comparative study of the reduction in apico-basal diameter has been made on 62 patients, first on pneumoperitoneum alone, and later on the same patients when pneumoperitoneum was combined with phrenic crush. 2. In “group A” of 32 patients who received 1000 cc. of air at seven to 10 day intervals, the average reduction in apico-basal diameter was 16 per cent with pneumoperitoneum alone, and 28.5 per cent after addition of phrenic crush; that is, phrenic crush caused a further increase in vertical relaxation by about 78 per cent. 3. In “group B” of 30 patients who received a maximum of 600 cc. of air at weekly intervals, the average reduction in apico-basal diameter was 8.4 per cent with pneumoperitoneum alone, and 23.8 per cent after addition of phrenic crush. 4. When pneumoperitoneum was used as a sole collapse measure, 600 cc. refills at weekly intervals did not give adequate rise of the diaphragm. When phrenic crush was added, it was seen that even 600 cc. refills at weekly intervals gave adequate rise of paralysed dome, and either no rise or insignificant rise of non-paralysed dome. 5. In eleven patients, phrenic paralysis on one side was performed first and pneumoperitoneum was added later. It was noticed that with phrenic paralysis alone on the left side, the average reduction in apico-basal diameter was 11.5 per cent and maximum was 23.3 per cent. Whereas on the right side, the average reduction was 9.3 per cent and maximum was 13.2 per cent. With the addition of pneumoperitoneum the average reduction was 31.3 per cent on left side and 32.5 per cent on the right side. 6. The vertical relaxation induced by pneumoperitoneum or pneumoperitoneum plus phrenic paralysis is distributed between different lobes, in different proportions depending on the site of the major lesions. 7. Pneumoperitoneum combined with phrenic paralysis slightly increases the transverse diameter of the base of the lung due to the shift of a mobile mediastinum and compensatory rib movements. This insignificant increase in transverse basal diameter was only present in those cases where the mediastinum was mobile and it did not materially neutralize or offset the benefits resulting from reduction in apico-basal diameter.