Outline the various cardiac reflexes and the mechanisms by which they maintain physiological homeostasis.

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College Answer

This question required candidates to provide an answer that integrates their knowledge of various
aspects of cardiovascular physiology. Cardiac reflexes are fast-acting reflex loops between the
heart and central nervous system that contribute to regulation of cardiac function and maintenance
of physiologic homeostasis. This was often overlooked by many candidates. For a good answer it
was expected that at least the chemo and baroreceptor, Bainbridge (elicited by stretch receptors
located in the right atrial wall and the cavoatrial junction), Cushing (result of cerebral medullary
vasomotor centre ischemia), oculocardic (provoked by pressure applied to the globe of the eye or
traction on the surrounding structures), Bezold-Jarisch (responds to noxious ventricular stimuli
sensed by chemoreceptors and mechanoreceptors within the LV wall) reflexes be mentioned and
described.
Syllabus: C1e, C1c,2g, C1g
References: Millers Anaesthesia Chp 16