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  #1  
Old 03-26-2011
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Heart The systolic time in this light headed dizzy patient!

A 60 year old female with a history of chronic lower GI bleeding due to diverticulosis, comes into the ER feeling light-headed and dizzy. Her heart rate is 192 beats per minute and her blood pressure is 60/40. Which of the following is most accurate regarding the cardiac cycle in this patient’s current state?

A - Systolic time is increased and diastolic time is normal length.
B - Systolic time is normal length and diastolic time is increased.
C - Systolic time is decreased and diastolic time is substantially decreased.
D - Systolic time is increased and diastolic time is decreased.
E - Systolic time is decreased and diastolic time is normal length.
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Old 03-26-2011
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Default c

the answer is c
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Old 03-26-2011
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C is the answer
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B - Systolic time is normal length and diastolic time is increased.
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Old 03-26-2011
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C. systolic time is decreased and diastolic is substantially reduced
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C - Systolic time is decreased and diastolic time is substantially decreased.
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C is answer: Diastolic decreased more than systolic, but both decrease.
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Old 03-26-2011
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In this case, hemorrhage will decrease the preload and venous return. It reduces cardiac ouput and blood pressure and via carotid sinus will increase sympathetic stimulation to the heart. There will be increase in heart rate and contractility, however the compensatory mechanism is incomplete.

Increased heart rate will decrease the time for ventricular filling during diastole (decreasing diastolic time), while increase in contractility due to sympathetic stimulation will decrease the systolic interval.

I will vote for C.
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Old 03-26-2011
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the answer : C


Quote:
Originally Posted by earthpole View Post
A 60 year old female with a history of chronic lower GI bleeding due to diverticulosis, comes into the ER feeling light-headed and dizzy. Her heart rate is 192 beats per minute and her blood pressure is 60/40. Which of the following is most accurate regarding the cardiac cycle in this patientís current state?

A - Systolic time is increased and diastolic time is normal length.
B - Systolic time is normal length and diastolic time is increased.
C - Systolic time is decreased and diastolic time is substantially decreased.
D - Systolic time is increased and diastolic time is decreased.
E - Systolic time is decreased and diastolic time is normal length.
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Old 03-26-2011
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Default C is the answer

definitely C
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Default c

the answer is c
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answer is C
1/3 of the cardiac cycle is attributable to systole and 2/3 to diastole. When a personís heart rate increases significantly the time spent in diastole decreases dramatically resulting in less filling time and a very inefficient pumping mechanism. At increased heart rates the time spent in systole decreases slightly.
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  #13  
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great job everyone
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