Thursday 27 March 2014

FCPS part 1 Medicine solved mcqs with explanation Q3



FCPS part 1 Medicine solved mcqs with explanatio


Q3: A patient with acute blood loss, the mechanism triggered immediately would be:
a) Baroreceptor Reflex
b) Renin-angiotensin System
c) Chemoreceptor
d) CNS ischemic response

Correct Answer: a

Explanation:
Most important and quick response in severe hemorrhage such as acute blood loss is the baroreceptor reflex. Baroreceptors are present in the aortic arch (signal transmitted via vagus nerve to medulla) & carotid sinus (signal transmitted via glossopharyngeal nerve to medulla). Barorecptors respond to changes in BP as following:
Hypotension àdecreased arterial pressure à decreased stretch on baroreceptors à decreased afferent baroreceptor firing à increased efferent sympathetic firing & decreased efferent 

No comments:

Post a Comment

Although every comment is appreciated, due to time limitations I might not be able to respond to every one. Comments are moderated and may take some time to appear. All spam comments will be deleted.