Outline the various cardiac reflexes and the mechanisms by which they maintain physiological homeostasis.
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
Syllabus: C1e, C1c,2g, C1g
References: Millers Anaesthesia Chp 16
In this answer, the college examiners again confused the connection between the question they asked and the answer they wanted. For example, there is no way one could possibly describe the oculocardiac reflex as something that "maintains physiological homeostasis", as it is a reflex which can drop you into asystole for 28 seconds. In short, many of the phenomena mentioned by the examiners are reflexes, but only the baroreceptor reflex and Bainbridge reflexes are concerned with the maintenance of homeostasis. Clearly, the real SAQ asked "Describe the various rapidly acting cardiac reflexes that influence cardiac function and the mechanisms by which they act". Or at least, that is what the college asked in the very similar Question 2 from the second paper of 2013, after they had three years to reconsider the stem phrasing. It did not help: in 2013, the pass rate was actually lower (22%).
Zucker, Irving H., and Joseph P. Gilmore. Reflex control of the circulation. CRC Press, 2020.
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Mancia, G., et al. "Reflex cardiovascular regulation in humans." Journal of cardiovascular pharmacology 7 (1985): S152-S159.