Alteration in the distribution of organ perfusion following profound hypothermia and circulatory arrest in the baboon.

The physiologic consequences of profound hypothermic circulatory arrest in infants are incompletely understood. Immature baboons underwent surface cooling, followed by core cooling using cardiopulmonary bypass, circulatory arrest for 30 min, and perfusion rewarming. Blood flow to and within organs was studied using the multiple-radionuclide-label microsphere technique.

Experimental barbiturate intoxication: treatment by partial cardiopulmonary bypass and hemodialysis.

1. The results of a series of experiments in which anesthetized mongrel dogs were instrumented and preparations for closed-chest partial cardiopulmonary bypass with membrane oxygenation and hemodialysis were made, following which "fatal" barbiturate intoxication was produced by the intravenous route has been presented. 2.

Cerebral effects of profound hypothermia (18 degrees C) and circulatory arrest.

Clinical use of profound hypothermia and total circulatory arrest has been accompanied by occasional postoperative neurological abnormalities. In a series of infant baboons, surface cooling to 32 degrees C (brain) followed by perfusion cooling by cardiopulmonary bypass with a membrane oxygenator and heat exchanger to 18 degrees C was carried out, after which the circulation was stopped for 30 minutes. The animal was rewarmed to 35 degrees C.

Hemodynamics and metabolic determinants of distribution of myocardial flow.

A computer simulation of the left coronary outflow response to branch occlusion was carried out, using physiological data derived from canine left coronary artery generated on an IBM 360/44 in order to provide multidimensional analysis of the problem of the distribution of flow within the myocardium. During coronary occlusion in this computer model, distal impedance varied little during the occlusion of one or the other arterial brance. This observation was taken as a boundary condition in the simulation exercise.