Editorial: The diaphragm and breathing.

On the basis of the anatomophysiological assumption that the abdominal oesophagus is kept in its seat by the meso-oesophagus and that the complex functional role of the gastro-oesophageal junction is conditioned essentially by the inferior oesophageal sphincter under the influence of intra-abdominal and endogastric pressure variables, posterior gastro-oesophagophreno-plasty (p.g.p.p.) is proposed to offset the destruction or severe insufficiency of the meso-oesophagus and hence for the treatment of hiatal hernia and of regurgitation. This retro-oesophageal tuberous valve involves simultaneous fixation of the stomach and oesophagus to the pillars of the diaphragm, first on the right and then on the left, and the fixation of the fundus to the left diaphragmatic dome. Anterior gastro-oesophago-phreno-plasty is proposed on the basis of the finding that damage of any kind to the meso-oesophagus can cause the oesophagus to rise in the chest and thus disturb inferior sphincter function and possibly lead to the onset of regurgitation and hernia. The pre-oesophageal tuberous valve employed involves simultaneous fixation of stomach and oesophagus to the pillars of the diaphragm, first left and then right, and the fixation of the fundus to the left diaphragmatic dome. Anterior plasty is almost always confined to patients who have undergone vagotomy of the trunk without complex isolation of the oesophagus.

Diaphragm↗

PubMed1979

The interaction between the diaphragm, intercostal/accessory muscles of inspiration and the rib cage.

During Mueller maneuvers (MM), the volume change of rib cage, delta Vrc, and abdomen, delta Vab, are equal and opposite. Thus delta Vrc = -delta Vab. Substituting delta Prc.Crc for delta Vrc and delta Pab.Cab for delta Vab yields: delta Prc = - delta Pab.Cab/Crc, where delta Prc, delta Pab, Crc and Cab are applied pressures and compliances of rib cage and abdomen respectively. MM performed solely with the diaphragm permits calculations of Prc in terms of observed changes in Pab and pleural pressure, Ppl. Three trained subjects performed MM with no evidence of inspiratory intercostal or abdominal muscle contraction. During the diaphragmatic MM delta Pab was positive and delta Prc negative. The magnitude of delta Prc/delta Pab was 2-6 times greater than that of delta Ppl/delta Pab. We conclude that neither Pab nor Ppl by themselves displace the relaxed rib cage during Mueller maneuvers. A model in which the diaphragm acts both in parallel and in series with the rib cage, and in which Prc is the sum of Pab and a pressure lying between Pab and Ppl explains these results as well as the hypothesis that Pab displaces the relaxed rib cage during quiet breathing.

Diaphragm↗