Acid-Base Equilibrium During Cyclopropane Anesthesia and Operation in Infants

Abstract

The effect of endotracheal cyclopropane anesthesia and operation on acid-base equilibrium in 30 unsedated infants was determined by preanesthetic and operative arterial blood analyses for pH, PCO2, and CO2. Anesthesia was administered via a nonrebreathing system, respirations spontaneous. The depth of anesthesia was correlated with the clinical signs of light anesthesia, the EEG, and in 10 cases with an arterial concentration of cyclopropane between 7 and 15 mg./100 ml.

Because of hyperventilation, the result of crying, most of the infants had a mild respiratory alkalosis before anesthesia. In addition, infants with pyloric stenosis exhibited a slight metabolic alkalosis preoperatively. There was no evidence of a respiratory acidosis during anesthesia and operation, and there was no change in the metabolic component of the acid-base equilibrium.