MOCA FRC question? Same FRC newborn vs adults?

[aneftp]

Trying to do some practice questions for the ABA MOCA. I heard the ACE exams were good for test questions.

Anyways, some of the questions are kinda of bogus and their reasoning is flawed a few times.

Had this question about FRC/Lung volumes Peds vs Adults.

When expressed as a function of weight, which of the following is Most likely to be greater in a healthy adult than in a healthy newborn?

The ACE choices were
tidal volume,
total lung capacity,
FRC
oxygen consumption.

I chose FRC which I have always thought was always higher in adults vs newborn. But I guess FRC is now considered the same in adults vs infants?

The answer was Total lung capacity is higher in adults vs infants.
The ACE exam said FRC was 30ml/kg in both adults and infants. But it also said TLC was 63 ml/kg in neonate vs. 82/ml/kg. I read several textbooks that stated TLC was the same as a per kg basis for both infants and adults previousl

I know the reason infants desat faster (higher MV/FRC). That's not what's bothering me. What's bothering me is I always thought adult FRC was greater than infants. Kinda of feel silly asking these questions but its bothering me a lot.

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[Idiopathic]

frc is the same, this has been tested for a while. oxygen consumption is higher in infants than adults, which is why they desaturate quicker. TLC is greater in adults, I think because of greater residual volume

 

[aneftp]

frc is the same, this has been tested for a while. oxygen consumption is higher in infants than adults, which is why they desaturate quicker. TLC is greater in adults, I think because of greater residual volume

Well I took the writtens 9 years ago.

At that time FRC in many text books was 25ml/kg for newborns and 35ml/kg for adults.

And TLC capacity mg/kg was the same for both groups.

Did they tweak the FRC teachings the past 8 years?

Spoke to my cousin who is attending at academic center and she says the peds guys have altered their teaching the last decade on FRC. She texted me this, "Per peds guy, kids have same Frc as adults while awake and less when sedated"

I feel like idiot or those questions are nick picking.

 

[nap$ter]

frc is the same, this has been tested for a while. oxygen consumption is higher in infants than adults, which is why they desaturate quicker. TLC is greater in adults, I think because of greater residual volume

this is correct. frc is the same per kilo. it is a change from historic teaching.

 

[Precedex]

Frc drops precipitously in the paralyzed/anesthetized infant because their chest wall compliance is much higher than an adult's. the awake infant maintains their frc dynamically at the same per kg volume but this is not the frc where recoil of lung = recoil of chest wall as it is in adults.

 

[aneftp]

Thanks guys. Good to get updated on some important information.

I know things in medicine can change rapidly and even being out for 9 years, you still need to keep up with changes from historical teachings. Like intralipid therapy wasn't a big topic when I was in residency but its common knowledge now.

Guess I got some touching up to do for the Moca cognitive exam in a couple of months. I just want to get the exam over with and not procrastinate until end of 2015 when my certificate expires.