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Old 04-27-2006, 10:27 PM   #1
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I found a couple and emailed the authors and the errata contact they give, and none of the emails worked. WTF!?

do you agree?

FA2006, page 218, Cardiac output variables, right column:
Myocardial O2 demand is increased by: 1. Afterload (proportional to diastolic BP)....should read proportional to SYSTOLIC PRESSURE.

FA2006, page 221, pressure-volume relationship, figure...
labels for ESV and EDV were switched around.
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Old 04-27-2006, 10:43 PM   #2
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I think First Aid is right on the first one.

I don't have 2006 edition so I can't comment on the second.
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Old 04-27-2006, 10:59 PM   #3
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I'm pretty sure the 1st one is right.....the pressure from the left ventricle must meet and surpass the resting diastolic pressure in the aorta (aka the afterload).....more of a pump needed to surpass the afterload = more 02 demand
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Old 04-28-2006, 12:03 AM   #4
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Quote:
Originally Posted by Taus
I'm pretty sure the 1st one is right.....the pressure from the left ventricle must meet and surpass the resting diastolic pressure in the aorta (aka the afterload).....more of a pump needed to surpass the afterload = more 02 demand
interesting. okay do you agree with this then...

afterload is proportional to Diastolic BP and TPR, but equal to systolic arterial pressure.

it says also on page 218 that afterload=systolic arterial pressure.

thanks for your input.
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Old 04-28-2006, 12:13 AM   #5
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Quote:
Originally Posted by TY06
interesting. okay do you agree with this then...

afterload is proportional to Diastolic BP and TPR, but equal to systolic arterial pressure.

it says also on page 218 that afterload=systolic arterial pressure.

thanks for your input.
Afterload is definitely not SAP. Afterload is the minimum force needed to overcome for the heart to eject blood, and as such is equivalent to the DBP. SAP>>afterload.
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Old 04-28-2006, 12:17 AM   #6
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Quote:
Originally Posted by Idiopathic
Afterload is definitely not SAP. Afterload is the minimum force needed to overcome for the heart to eject blood, and as such is equivalent to the DBP. SAP>>afterload.
what you guys say 100% makes sense.

so then is there a mistake on the same page where it says

afterload=systolic art pressure??

thanks.
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Old 04-28-2006, 01:48 AM   #7
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at first i thought "afterload = systolic arterial pressure" was wrong too, but now i think it's actually correct as well. in Lilly's Pathophysiology of Heart Disease it says that the afterload is "often approximated by the systolic ventricular (or arterial) pressure."

also, afterload can also be defined as the ventricular wall stress that develops during systolic ejection. in Dorlands Medical Dictionary it says that ventricular wall stress can be estimated by systolic arterial pressure using the LaPlace relation.

so basically what i got from all this is:
systolic arterial pressure = systolic ventricular pressure ~ afterload
*apparently only under normal conditions, i read in PreTest Phys that aortic stenosis causes ventricular pressure to be higher than the arterial pressure.

i still don't see how diastolic BP and systolic arterial pressure can BOTH equal afterload though...
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Old 04-28-2006, 10:11 AM   #8
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Hey All,

the FA guys posted a couple of pages on the website (the inside flap, page 182, & page 319.) I would upload them, but they're over the size limit. (PM me if you know how to get around this.) The douchely thing is, you have to register to get them.

Now if you'll excuse me, I'm going to go post this identical post in the other FA errors thread.

http://books.mcgraw-hill.com/medical...dfortheboards/
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Old 04-28-2006, 10:16 AM   #9
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Quote:
Originally Posted by Sadame
at first i thought "afterload = systolic arterial pressure" was wrong too, but now i think it's actually correct as well. in Lilly's Pathophysiology of Heart Disease it says that the afterload is "often approximated by the systolic ventricular (or arterial) pressure."

also, afterload can also be defined as the ventricular wall stress that develops during systolic ejection. in Dorlands Medical Dictionary it says that ventricular wall stress can be estimated by systolic arterial pressure using the LaPlace relation.

so basically what i got from all this is:
systolic arterial pressure = systolic ventricular pressure ~ afterload
*apparently only under normal conditions, i read in PreTest Phys that aortic stenosis causes ventricular pressure to be higher than the arterial pressure.

i still don't see how diastolic BP and systolic arterial pressure can BOTH equal afterload though...
Just keep it simple. Afterload is the pressure against which the heart must eject blood. If afterload were equivalent to SAP, then how would blood move? Everything would be in equilibrium = no pressure gradient. SAP must be greater than afterload.
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Old 05-11-2006, 05:48 PM   #10
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I just spotted these a moment ago.

Page 345 - I think the directions of eye movement is incorrect. the oblique muscles are incorrectly swapped with the superior and lateral recti.

page 344. Cavernous sinus syndrome should say "maxillary" sensory loss, not mandibular.
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Old 05-11-2006, 06:04 PM   #11
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Quote:
Originally Posted by GED MD
Hey All,

the FA guys posted a couple of pages on the website (the inside flap, page 182, & page 319.) I would upload them, but they're over the size limit. (PM me if you know how to get around this.) The douchely thing is, you have to register to get them.

Now if you'll excuse me, I'm going to go post this identical post in the other FA errors thread.

http://books.mcgraw-hill.com/medical...dfortheboards/
thanks for the link. i flipped to those pages within the 2006 copy and they were nothing like the corrected ones posted online. weird, i guess those pages were omitted from 2006.
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Old 05-11-2006, 07:03 PM   #12
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Quote:
Originally Posted by rager1
I just spotted these a moment ago.

Page 345 - I think the directions of eye movement is incorrect. the oblique muscles are incorrectly swapped with the superior and lateral recti.

page 344. Cavernous sinus syndrome should say "maxillary" sensory loss, not mandibular.
The eye diagram is correct, though you are right in that they are not talking about the movements. If you adduct the eye, the "only" muscle that can lower it is the superior oblique. This differs from the actual movement of superior oblique, which is to abduct and lower. Hence, this diagram has more to do with testing the muscles than the actual movements of the muscles.

Correct me if I'm wrong though.
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Old 05-11-2006, 07:50 PM   #13
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Quote:
Originally Posted by IrishMD08
The eye diagram is correct, though you are right in that they are not talking about the movements. If you adduct the eye, the "only" muscle that can lower it is the superior oblique. This differs from the actual movement of superior oblique, which is to abduct and lower. Hence, this diagram has more to do with testing the muscles than the actual movements of the muscles.

Correct me if I'm wrong though.
the heading of the section with eye movements reads "direction of eye movements by extraocular muscles." going by this the diagram is incorrect.

the obliques abduct, and the superior/inferior recti adduct the eye.
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Old 05-11-2006, 09:16 PM   #14
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Quote:
Originally Posted by TY06
I found a couple and emailed the authors and the errata contact they give, and none of the emails worked. WTF!?

do you agree?

FA2006, page 218, Cardiac output variables, right column:
Myocardial O2 demand is increased by: 1. Afterload (proportional to diastolic BP)....should read proportional to SYSTOLIC PRESSURE.

FA2006, page 221, pressure-volume relationship, figure...
labels for ESV and EDV were switched around.
I was studying Cardiac physiology today and noticed the same error about the EDV and ESV being switched. If you look at BRS Physiology, they are switched to the correct position.
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