Diaphragmatic fatigue in man

摘要: The time required (tlim) to produce fatigue of the diaphragm was determined in three normal seated subjects, breathing through a variety high alinear, inspiratory resistances. During each breath all experimental runs subject generated transdiaphragmatic pressure (Pdi) which predetermined fraction his maximum Pdi (Pdimax) at functional residual capacity. test performed until unable generate this Pdi. relationship between Pdi/Pdimax and tlim curvilinear so that when small increased markedly for little changes Pdi/Pdimax. value could be indefinitely (Pdicrit) around 0.4. Hypoxia appeared have no influence on Pdicrit, but probably led reduction greater than Pdicrit equal rates energy consumption. Insofar as behavior reflects other respiratory muscles it appears quite loads can tolerated indefinitely. However, consumption exceeds critical level, should develop. This may mechanism failure lung diseases.