BILATERAL CERVICAL VAGOTOMY: A LONG-TERM STUDY ON THE UNANESTHETIZED DOG.

Abstract

Bilateral cervical vagotomy was followed by prolonged changes in heart rate, blood pressure, and respiration, and a progressive deterioration of cardiac function. This study was based on recordings from 18 unanesthetized, unrestrained, reclining dogs prior to and after gastroenterostomy, arterial catheterization, and bilateral cervical vagotomy. During the first 7 days after denervation, the heart rate was almost doubled and the pulse pressure was decreased. The diastolic pressure was increased only on the first day, whereas on the second day after denervation the systolic pressure became significantly lower. The markedly elevated heart rate was maintained for 3 weeks. There was a complete loss of inspiratory tachycardia for 20 weeks, a prolonged inspiratory period for 2 weeks, and a high incidence of retching and vomiting for over 43 weeks. Although the animals refused to exercise strenuously, they were fully ambulatory and showed normal interest in their surroundings. Death in 13 cases occurred by the second week postvagotomy and was associated with lung congestion or consolidation, and in two cases the liver had a nutmeg appearance.