NBME Answers : skinnynomore's page

Comments ...

+5 (nbme24#12)

They’re giving a lot of confusing extra information here, maybe to trip us up. They just want volume of distribution, simple as that.

Vd = [drug administered] ÷ [plasma drug concentration]

First convert it all to g/L because this is how the answer will be:

administered: 80 mg = 0.08 g plasma concentration: 4 ug/ml = 0.004 g/L

Thus,

Vd = 0.08 grams ÷ 0.004 g/L = 20 L

Clearance of drug is not a huge factor because the half life is so long that the drug is distributing before significant clearance occurs.

gonyyong I think the distribution half-life and elimination half-life was saying that by the time you checked, it had fully distributed (10 half-lifes) and had not been cleared yet (super long half-life)

soph 1000ug= 1mg and 1g=1000000ug so then 4ug/ml * 1g/ 1000000ug= 0.000004 g/ml 0.000004g/ml * 1000ml/L= 0.004 g/L 80mg*1g/1000mg= 0.08 g vd= 0.08g/ 0.04g/l =20L

Subcomments ...

submitted by aerrow3(-1),

What are we supposed to be seeing on the MRI? Or do you just base it off the patient being an alcoholic with hip problems? I would’ve assumed avascular necrosis would’ve shown something on the X-ray but the x-ray showed no abnormalities so idk if the MRI is showing something?

skinnynomore alcoholic in the hx should point you towards avascular necrosis when there is an “atraumatic” complaint +

batrays http://radsource.us/avn-of-the-hip/ +

submitted by gainsgutsglory(5),

Why is this Intersitial Inflammation? I understand this is a VUR causing hydronephrosis.

skinnynomore this kid has chronic pyelonephritis due to recurrent UTIs (VUR/hydronephrosis is a risk factor). And -itis = inflammation. That was my take on it. +2