Anaesthetic agents might modify these responses, and thus result in greater damage to the animal or human during hypoxia. This study aims to examine the effects of one anaesthetic agent (sevoflurane) on this response to hypoxia. Sevoflurane is a widely used modern anaesthetic agent. The effects of sevoflurane on integrated protective reflexes to hypoxia are not well defined. Controversy remains regarding the possible site(s) of action within the arterial chemoreceptor reflex arc where sevoflurane and other anaesthetics exert their depressant effects. These effects are mediated by both peripheral and central nervous mechanisms. The proposed study will allow the investigation of sevoflurane in an integrated whole animal model. Severe arterial hypoxia is known to activate peripheral chemoreflex mechanisms in the rabbit. By analysing both the behavioural and cardio-respiratory changes that occur to these reflex mechanisms before and during sevoflurane administration, it will be possible to assess not only the mechanisms of action of this drug, but further
the role of chemoreflexes during surgical procedures requiring anaesthesia.
1. To characterise the effect of increasing doses of sevoflurane on the ventilatory response to hypoxia
2. To characterise the effects of increasing doses of sevoflurane on the cardiovascular responses to hypoxia"
Professor Anthony Quail