Miguel is a 25-year-old jogger with a target heart rate of 125 bpm. His resting pulse is 70 bpm. His blood volume is approximately 6.8 litres. At rest, his cardiac output is 6.3 litres/minute and his EDV is 150 ml. What is his stroke volume at rest?

Question

3979 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-04-07T23:45:15

$0.09 ("Liters")/("beat")" at rest"$

The equation that is going to be helpful for us is the following:

$color(white)(aaaaaaaaaaaaaaa)color(blue)(CO = HR * SV)$

Where:

$"CO=cardiac output: volume of blood the hearts pumps out"$
$color(white)(aaaaaa)"every minute (mL/min)"$

$"HR=heart rate:the number of beats per minute (beats/min)"$

$"SV= stroke volume:volume of blood pumped out by the"$
$color(white)(aaaaaa)"heart in 1 beat (Liters/beat)"$

$---------------------$

Isolate the unknown, plug in and solve.

Given

$"CO" = 6.3 "Liters"/("min")color(white)(---)"HR" = 70 "beats"/("min")$

$color(blue)(CO = HR * SV)$
$color(white)(--)$
$(CO)/(HR) = SV$
$color(white)(--)$
$(6.3 "Liters"/cancel(min))/(70 "beats"/cancelmin) = "SV" = 0.09 ("Liters")/("beat")$

$color(orange)("Answer": "SV"= 0.09 ("Liters")/("beat")" at rest")$