cardio 5

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cardio 5

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4 Posts

kris2c
Forum Senior

Topics: 30
Posts: 108

02/18/04 - 12:59 PM

Respiratory rate: 15/min

Blood pressure: 120/80 mm Hg

Cardiac output: 5 L/min

Heart rate: 50/min

A 25-year-old man is participating in a clinical study to determine the cardiovascular response to physical exercise. Basal measurements are shown above. What is his stroke volume during resting conditions (in mL)?
A. 50
B. 75
C. 100
D. 125
E. 150

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Kris2c

dxtxpx
Forum Guru

Topics: 259
Posts: 1,233

02/18/04 - 01:18 PM

choice c)100

auubar
Forum Senior

Topics: 30
Posts: 182

02/19/04 - 01:26 AM

kris2c
Forum Senior

Topics: 30
Posts: 108

02/19/04 - 07:35 AM

Good guys

The correct answer is C.

The cardiac output (CO) is equal to the volume of blood ejected from the heart during each systole (i.e., the stroke volume; SV) multiplied by the number of times the heart beats each minute (heart rate; HR). In other words,

CO = SV x HR.

Therefore, SV = CO/HR,

and since CO = 5000 mL/min, and HR = 50/min, SV = 5000/50 = 100 mL.

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Kris2c

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