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  #1  
Old 11-25-2011
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Question cranial nerves IX and X are accidentally cut bilaterally

Q. 59. During surgical removal of an invasive glioma from the skull base, cranial nerves IX and X are accidentally cut bilaterally. What would be the immediate change in the patient's hemodynamic condition?
A. Bradycardia with hypertension
B. Bradycardia with hypotension
C. Sinus arrhythmia with hypotension
D. Tachycardia with hypertension
E. Tachycardia with hypotension
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Old 11-25-2011
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not sure attempting...D...as hes in surgery n cn cut so no reflex on heart
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  #3  
Old 11-25-2011
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Arrow D

its D

Whats the correct ans?
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Old 11-25-2011
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I will go with D decrease vagal activity result in decrease parasympathetic effect in HR and glossopharyngeal injury part of carotid response will result in deccrease firing hence increase sympathetic activity on blood vessels resulting in HTN
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Old 11-26-2011
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D it's a kaplan q. thanks for posting it.
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Old 11-26-2011
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D is the correct answer and B if you stimulate the IX
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Old 11-27-2011
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he answer is C.

The glossopharyngeal nerve (CN IX) and the vagus nerve (CN X) carry afferent information to the medulla from the carotid sinus and aortic arch baroreceptors, respectively. The firing rate of these neurons increases with increasing blood pressure. Therefore, stimulation of the glossopharyngeal nerve sends the medulla a false signal that the animal has suddenly had an increase in blood pressure. This elicits a baroreceptor reflex resulting in a decrease in sympathetic outflow and an increase in parasympathetic outflow, leading to hypotension and bradycardia.
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Originally Posted by miss patho View Post
he answer is C.

The glossopharyngeal nerve (CN IX) and the vagus nerve (CN X) carry afferent information to the medulla from the carotid sinus and aortic arch baroreceptors, respectively. The firing rate of these neurons increases with increasing blood pressure. Therefore, stimulation of the glossopharyngeal nerve sends the medulla a false signal that the animal has suddenly had an increase in blood pressure. This elicits a baroreceptor reflex resulting in a decrease in sympathetic outflow and an increase in parasympathetic outflow, leading to hypotension and bradycardia.
I think thats not the right answer as when the nerves are cut it will resemble a state of hypotension which will lead to sympathetic firing and increase in HR and BP. Atleast this is what the KPN says.

So i think the ans is still D
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Hey I agree to! Cutting of the nerves would signal a drop in BP, so I think its D.
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Old 07-16-2012
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Correct Answer The correct answer is D

The correct answer is D. The glossopharyngeal nerve (CN IX) and the vagus nerve (CN X) carry afferent information to the medulla from the carotid sinus and aortic arch baroreceptors, respectively. The firing rate of these neurons increases with increasing blood pressure. Therefore, severing these nerves sends the medulla a false signal that the patient has suddenly lost all blood pressure. This elicits a baroreceptor reflex, resulting in an increase in sympathetic outflow and leading to tachycardia and hypertension.
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