Failure of Physiologic Parameters as Predictors of Acute Upper Airway Obstruction

Abstract

At the recent spring meeting of the American Broncho-Esophagological Association in San Francisco, Calif, Drs Eisele, Coltrera, Bright, and Weymuller, all from Seattle, Wash, presented a paper on physiologic changes during acute upper airway obstructions. Their goals included (1) to develop an awake animal model of variable upper airway obstruction with the airway intact, (2) to measure airway resistance, and (3) to use the animal model to evaluate acute airway obstruction. Their experimental design called for the use of a goat and the placement of Swan-Ganz catheters into the trachea transcutaneously. With these catheters in place and an airtight mask over the animal's face, a pneumotachometer was used to collect data. Other physiologic parameters that the investigators monitored included blood pressure, heart rate, electrocardiogram, respiratory rate, arterial blood gases, and physical examination changes. Using variable degrees of acute airway obstruction, the investigators found no consistent physiologic parameter changed, except for