Hemodynamics during superficial thiopental anesthesia in the dog.

Radioactive microspheres, labeled withe ytterbium (169Yb), strontium (85Sr) and cerium (141Ce) were used in an investigation of the cardiovascular response to superficial thiopental anesthesia. The course was followed for 90 min and measurements were carried out 30, 60 and 90 min, respectively. Between 30 and 60 min of anesthesia there was a slight decrease in cardiac output and left ventricular work. The blood flow was reduced to the lungs, kidneys and the liver. Between 60 and 90 min there were, except for the coeliac artery and total liver, no further changes, which indicated a circulatory steady state.