Hernodynamics during Superficial Thiopental Anesthesia in the Dog

Abstract

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.

The Effect of Halothane on the Distribution of Cardiac Output and Organ Blood Flows in the Hemorrhagic, Hypotensive Dog

“…Preparation of the animals Five to eight days before the experiment, a polyethylene catheter (Seldinger 160) was inserted in the left atrium as described elsewhere ( AHLGREN et al 1978a). On the day ofthe experiment, the animals were given a small dose of Pentothale (Abbott) to maintain superficial anesthesia (AHLGREN et al 1978a) a t a depth just sufficient to permit endotracheal intubation.…”

“…Determination of CO was made with the dye dilution method (WASSBN 1956). The hematocrit was determined and the blood gases were analyzed according to previously described methods (AHLGREN et al 1978a). The heart rate was measured from the electrocardiogram (Elema-Schonander, Sweden) ; the stroke volume, the left ventricular work, the systemic vascular resistance and individual organ vascular resistance were calculated as previously described (AHLGKEN et al 1978a) from data obtained during the experiment.…”

The Effect of Halothane on the Distribution of Cardiac Output and Organ Blood Flow in the Hypovolemic Dog

“…The hematocrit was determined and the blood gases were analyzed according to previously described methods ( AHLGREN et al 1977a). The heart rate was measured from the electrocardiogram (Elema-Schonander, Sweden) ; the stroke volume, the left ventricular work, the systemic vascular resistance and individual organ vascular resistance were calculated as previously described ( AHLGREN et al 1978a) from data obtained during the experiment.…”

“…pm in diameter, were labeled with different nuclides, ytterbium ( lSgYb), strontium ("Sr) and cerium (I4'Ce), respectively. The handling of the microspheres, measurement of radioactivity and calculation of organ blood flow were done according to methods described previously (Ahlgren et al 1978a).…”

“…None of the studies cited above, however, gives any information on the distribution of cardiac output (CO) and the blood flow to different organs during halothane and hypovolemia. The purpose of the present investigation was, therefore, to assess the effect of halothane on the cardiac output and organ blood flows during hypovolemia using the radioactive microsphere technique, introduced by RUDOLPH & HEYMANN (1967) and described elsewhere (AHLGREN et al 1978a). The effect of blood transfusion on the recovery from a preceding halothane anesthesia during hypovolemia was also studied.…”