Biomedical subjects

F J Walters

Publications and source records attributed to F J Walters.

20 records · Page 2Linked to original sources

PubMedDate not supplied

Effect of hypotension induced by ATP and adenosine on brain surface oxygen tensions in the sheep.

A multitipped oxygen electrode has been used to measure cortical surface oxygen tensions in the sheep. A histogram of the pattern of supply of oxygen to cortical tissue within the microcirculation during normal conditions is presented. Systemic arterial pressure was reduced to a mean of 30 mmHg with either Adenosine or ATP, and further oxygen tension measurements undertaken. The oxygen histogram was shifted to the left in these circumstances, and there was an increase in the frequency of occurrence of very low tissue oxygen tensions. This suggests that the use of these agents to induce profound hypotension may be associated with significant ischaemia within the microcirculation.

Adenosine↗

PubMedDate not supplied

Effect of carotid artery ligation and infusion of fluosol FC-43 emulsion on brain surface oxygen tensions.

In eight rabbits, the common carotid artery was ligated and multiple estimations of brain surface oxygen tension performed using a seven barrelled mini-electrode. In five rabbits ligation of the carotid artery resulted in impairment of cortical oxygenation. The remaining three rabbits showed no impairment in the supply of oxygen to the cerebral cortex after carotid occlusion. In the five rabbits who displayed a reduction in oxygen supply after carotid ligation, ventilation with 33% oxygen after the infusion of 15 ml/kg of Fluosol FC-43 produced an improvement in cortical oxygenation in only three of the five rabbits. When these animals were ventilated with 100% oxygen after carotid ligation and Fluosol infusion, oxygen supply in all five was commensurate with or greater than that during control conditions.

Animals↗