Altered Perfusion, Ventilation, Anesthesia and Lung-surface Forces in Dogs

Abstract

The combination of hyperventilation, lowered pulmonary blood flow and pentobarbital-O2 anesthesia led to a progressive increase in retractive forces of the lung accompanied by a gradual reduction in inflatable volume in dogs studied for eight hours. After four hours of ventilation, significant changes began to appear at the higher transpulmonary pressures. Results after four hours of ventilation were similar in other dogs treated identically except for the addition of 1.2 per cent halothane to the inspired gas. Hyperventilation and the absence of pulmonary arterial blood flow led to significant (P