DIP Episode 642 - USMLE Free 86 Series 4 (Q31-36, for Step 2/3)

Alright, welcome to episode 642 of the Divine Intervention Podcasts. Today we're going to be continuing the 386 series. This is going to be series 4. Again, if you're studying for step 2 or step 3, do not ignore this series. This is actually sneakily high yield for the exams. Alright, let's go to question 31. A 74 year old white man with dementia is transferred to the ED from a nursing facility because of necrosis of the distal phalanx of the second tooth on his right foot. He denies localizing pain. He has a history of hypertension, coronary artery disease, CHF and malrinolein sufficiency. Vital signs are a temperature of 98.6, pulse of 92, respiration of 16 and blood pressure of 160. On physical examination, his thinnerness in no distress. Chest has bilateral crackles at both long bases. Hardiac and abdominal examination discloses no abnormalities. The extremities are thin and the distal phalanx of the second right toe is black. Maldery thema is present on the adjacent proximal skin but no purulence is noted. Bilateral corroded and femoral artery bruise are noted. Radio pulse is reform. A pulsar tal mass measuring approximately 2 cm is palpable in the right popliteal fossa. Dorsal is P Ds and posterior tibial pulse is a 3 plus bilaterally. Which of the following is the most likely cause of this patient's gangrene? A, arterial embolus. B, hyperquaglophone or thrombophilic state. C, obliterative angiopathy. D, poli-adritis nodosa. E, renal syndrome.

So we see this person, they have gangrene of something on their right foot, right? Second on the right foot. And then we see in this question, the give us the finding of this person basically having a pulsar tal mass in the right popliteal fossa. What do you think that pulsar tal mass is? You have a pulsar tal mass, it's likely some kind of aneurysm. Aneurysms are very, very worrisome for embolus development. Because basically it's almost like a fusing form enlargement of the wall of the vessel. So because you have like this enlargement, you almost have like a place where blood there's like troubling flow of blood. And it's almost like the blood has more time to chill in that region. The fact that you're going through troubling flow doesn't mean that you cannot have blood stasis, right? So those aneurysms, right? Because again, it's almost like you have this straight road and then you have this side rest area. You know, let's just kind of think of traveling on the highways in the US. You're driving on a straight road and then you take a detour to a rest area. You know, that rest area, you're driving there, you'll sit down, you'll park your relax, right? So aneurysm is like that place you're driving to a block and driving to sit down, park and relax, right? You can be having trouble and flow within the vessel, right?

So again, that side part of the vessel, you can begin to form, embolite there because of the blood stasis, think of wrinkles, try it and then you can form an embolite that can flick off and go on or close the vessel, right? So this is actually part of why aneurysms are dangerous, right? Many people think of aneurysms just in terms of rupture risk, but actually another risk with aneurysms is that it can not just rupture, but embolite can form there. That's why having an embolite in the brain, like an aneurysm in the brain is problematic. Because number one, it can pop with number two, you can form an embolite that can then go to a cerebral vessel and cause problems, right? And most times when we treat an aneurysms, we're going to go ahead and coil those aneurysms, right? We're going to go ahead and coil those aneurysms, right? So I'm going to go with option A, right? A serial embolite is the likely cause of this person's problem, right? Option B, hypercoglabel of thromophilic state. Yeah, you know, he does have hypercoglabel risk factors, but again, I feel like option A is like directly mentioned in the question. You can see it talks about obliterative angiopathy. That's something we find in like, burger's disease, right? Thrumbo angiitis obliterance, right? Usually those people are going to be like big time smokers. And as far as I can tell, I don't see like a smoking history in this question. And then D, poliaritis nodosa, right?

It's probably something that was shot quite a bit earlier in life, right? And again, they will have like vascular lesions that have like the string of beets pattern, right? We don't see that here, right? So we're not going to see poliaritis nodosa, right? And most times when poliaritis nodosa, they have like a lot of abdominal pain, right? They will have like, they can have like joint pain, they can have like neuropathy, although remember that pa and spares the lungs, pa and those spares the lungs, right? And then renal syndrome will say like temperature, dependent changes in profusion to a person's extremities, right? We don't see that here. Right? So that's wrong. So the right answer is going to be option A here. All right. Now, question 32 says 76 year old German American man comes to the office because of early a weekning at night. He has no difficulty falling asleep, but routinely wakes up between 2 a.m. and 3 a.m. The patient is a retired post-oh worker and he has always been physically active. He has diabetes mellitus controlled by diet. He is not obese. The patient drinks one cup of coffee in the morning with breakfast and usually walks for exercise in the morning. Before retiring at night, he has one alcoholic drink. He has no history of depression, nightmares or snoring and he takes no over the counter medications. His wife for 45 years is also in good health.

Vital signs are a temperature of 98.8, pulse of 96, that is regular, respiration is 18 per minute and blood pressure is 135 over 90. Physical examination shows a well nourished, well developed man. Examination of the head and neck is normal. There are no bruise or GVD. Most is clear, hurt is normal with S1 and S2. Abdomain is soft and non tender with active bowel sounds and nor organometalline. Rectal examination is normal, which of the following is the most appropriate management of this patient in Somnia. Soption A says, advice the patient to discontinue his bedtime drink of alcohol. B says, advice the patient to read and snack in bed to relax. Option C says, prescriber vigorous pre bedtime exercise regimen. And D says, prescrib set rolling. Option E says, prescrib triazolab. Alright, so let's see what's going on here. So it seems like this guy has in Somnia and again, he is old, as the person gets older, unfortunately in Somnia begins to set in. They can sleep fine but again, they have early morning a week. So that's part of something that happens with the agent. So let's see what answer here makes sense. I don't think I'll be prescribing a benzo for sleep. That doesn't really make any sense because benzoes, they actually don't really give much in terms of durable improvement in sleep quality. I would not prescribe a benzo for sleep on the US Emily exams, certainly would not. And then option D says, set rolling.

Set rolling is for measure depressive disorder is not for sleep. So that's wrong. Measure depressive disorder anxiety or whatever, it doesn't have any of those things. And then option C says, prescrib vigorous pre bedtime exercise regimen. And I certainly would not do that. Don't get me wrong. Exercise is actually very helpful for sleep. Certainly, something I have noticed in my life that when exercise pretty good, I tend to sleep pretty well. But exercising pre bedtime is going to turn up your agronergic system. That will actually worsen your sleep. That may actually make it difficult for you to fall asleep. And then option B says, advise the patient to read and snack in bed to relax. That's not a smart idea, right? You're literally teaching this guy on healthy habits, right? This guy already has diabetes, malitis. It doesn't seem like a particularly great idea to do that, right? And actually, when people read and snack, I mean, when people snack, you know, like, I've actually seen this, you know, after you investigate this some more, so don't quote me on this. But I've actually heard that when people eat, the leader people eat, the worst their sleep is, right? But I don't know whatever mechanism there is behind that. I think that's true. But again, but no, right? This guy has diabetes. You probably don't want to be doing option B, right? And then option A, stop drinking before you sleep. Yeah, that's the right thing to do, right? Many people do not realize this.

You may think that, oh, wow, if I drink up, it's going to help me sleep up. No, you're not going to get better sleep from alcohol. Alcohol actually messes you up in many, many different ways, right? So like number one, think about it, right? This is actually a sleep question, right? Remember that in sleep, we have these, you know, there are all these feces of sleep. There's delta wave sleep. There is REM sleep. There is that, right? So the thing is REM sleep is, you know, one of those feces of sleep that, you know, is very restorative and things like that, right? Alcohol is a REM sleep inhibitor, right? So you're literally sacrificing your REM sleep on the ultra of alcohol, right? So that's one bath in alcohol dose to you, but that's not all, right? Alcohol, remember, it's not like you take alcohol and you're chilled the whole time. No. After that alcohol is metabolizing your body, you're going to start withdrawing from it. That mild withdrawal effect is going to promote weak fullness, right? So you're not going to end up, it's just like, yeah, you're getting like that weak fullness from withdrawal. That's going to disrupt your sleep, right? That is absolutely going to disrupt your sleep, right? So alcohol messes sleep up in many different ways, right? It doesn't, doesn't really help you as much as you think, right? Even I mean, think about this, this guy is 76 years old, right? He's a man, right? Old people tend to have a bunch of urinary problems, right?

Like, you know, maybe BPH. Again, yes, it's not said here that he has BPH, but the thing is alcohol is a diuretic, you know, alcohol is a diuretic. So if you're an old person and you potentially already have urinary problems, do you think it's a good idea to be taking something that's a diuretic that's going to be making you wake up more frequently at night to one peak, right? That can disrupt your sleep, right? BPH can actually be a sleep disruptor, right? So if you're taking a diuretic, that can also be a sleep disruptor, right? So alcohol just causes a bunch of sleep problems that are not ideal, right? So that's why option A is, right? This person should stop drinking at before, before bedtime, all right? And then questions 33 and 34, right? So one month old white boy whom you soared birth is birth to the office for a routine well-child visit. His birth history is unremarkable except for mild jaundice that's subsided within a few days. His birth weight was 6 pounds, right? So 2718 grams, so at the 10th percentile. And length was 50 centimeters, so 19.5 inches at the 30th percentile. His mother stopped breastfeeding when he was 6 days old. At today's visit, the infant is alert and active and he cries until fed. He weighs 3.2 kilograms, that's 7 pounds, that's the 5th percentile. And he's 54.6 centimeters, that's 21.5 inches, 25th percentile, right? So he's 21.5 inches long. His mother tells you that even when caughted, the infant cries continually until fed.

He always eats slowly, falling asleep before he finishes his formula. You find that formula flows adequately from the bottle nipple and you detect no abnormalities on physical examination of the boy to explain his slow feeding. The reneation and stooling patterns are normal. Serum urea nitrogen concentration is 10 and serum thyroxin T4 concentration is 10. Micrograms per deciliter. So the urea nitrogen is 10 milligrams per deciliter. Phyroxin is 10 micrograms per deciliter. So question 33 says which of the following is the most appropriate next step? A says advice his mother to resume breastfeeding. B says hospitalized the infant for parentary hyperalimentation. C says prescribe hypercaloric formula. So 24 calories per ounce. Option D says prescribe liquid multivitamines. Option E says schedule him for placement of a feeding gastroastomy tube. Right? So if you notice here in this question, right, this child seems otherwise fine. It's just that this child seems to be crying a lot. And then this child feels better after they're fed. So you know what? Maybe this child is telling mommy that hey, mom, I'm kind of hungry. Like I kind of need some food here. I kind of need some food here. So this mom should maybe feed this child some more. So the right answer that involves basically feeding the child some more is option C. Multivitamines are not food. So D is wrong. This child is pretty fine. Popein, peen, fine. Why would you want to do a gastroastomy tube? That seems extreme.

Hospitalizing the infant. Again, this infant is fine. He just needs more food. So don't pick B. And then option A, advice is model to resume breast feeding. That's not a patient centered answer because the woman is bottle feeding. Bottle feeding is not a crime. There are some people that struggle with breast feeding or they have like to work or whatever, right? Where bottle feeding is what they can do consistently, right? So option A is wrong, right? Option A is probably an unethical thing to do. Although breast feeding is better, right? Because it does a lot of good for the baby, but that's not the point of this question. This child is just not eating enough, right? So option C makes the most sense, right? Prescribed hypercaloric formula, right? 24 calories per ounce because the thing is number one, the child sucks well, but the child feeds slowly. But the problem is newborns sometimes they just fall asleep on a whim, you know, like, like you can barely keep them awake to eat, right? So it's almost like whatever little feeding window you have for this child, you have to maximize it, right? So giving hypercaloric formula is really good, right? Is really good because it's like the child can feed for a short time, but they get a ton of calories from that meal, right? They get a ton of calories from that meal, right? So even if they fall asleep, at least if eating enough to where they're kind of tanked up, right? So that's why option C is a better answer.

And then question 34 says at a full or visit one week later, which of the following factors would most likely indicate satisfactory progress in the treatment of the infant's problem? A, the infant does not cry before feeding. B, the infant finishes his formula at each feeding. C, the infant no longer falls asleep while feeding. D, the infant's weight increases by at least 0.2 kilograms, that's 0.4 pounds. E, serum, urea nitrogen concentration decreases to six. Again, if you've ever done any pizza rotation or you have kids, there's a reason why the pediatricians check the babies waited every visit, right? Why is just a very good indicator of, oh, is this child eating well enough or not? Right? So option A makes no sense. The infant does not cry before feeding. Infants cry, right? That's how they tell you that they need something. That's wrong. B says infant finishes his formula at each feeding. Yes, finishing your formula at each feeding is good. But what if the amount of formula you're getting is small? So that tells us nothing, right? C says the infant no longer falls asleep while feeding. No, right? Because again, babies, especially newborns, they're growing so fast, they need all the sleep that they can get. A newborn can sleep for almost like 1920 hours in a single day. Right? So that's wrong. Option D says the infant's weight increases. Yeah. Right? Infant's weight increases. That's going to be the right answer. Right?

So if your weight is increasing, that means like the food is getting in. Right? And then option E says serum urea nitrogen concentration decreases to six. If your BUN decreases, yeah, maybe it's indicative of better in all function or whatever, but that doesn't really correlate well with a child's nutritional status. Right? So that's wrong. I'm going to go with option D here. All right. Now a 62 year old woman is brought to the emergency department. And you see from that question that the child, you know, it's kind of dropping percentiles in terms of weight, right? That tells you that this child needs more food. This child needs more more food. All right. So a 62 year old woman is brought to the ED because of optimization. On physical examination, she has hypertension and tachycardia. Our respirations are 24 per minute. She has cherry red maculae on fundoscopic examination results of initial lab studies are shown. Right. So her serum urea nitrogen is 37. Sodium is 139. You know what? I'm not going to read off all these values, right? But let me pick up on the things that are abnormal here. Right. So this person's you should be having this PDF in front of you as you're listening to this podcast. Right. So this person, some things that kind of stick out to me that, these things are not great. Again, I don't know the number of values of every lab, but this person's potassium is not good, right? Potassium of 6.1 is not good, right? Bicarb of 10 is pretty low. It's pretty low.

The potassium is pretty high. Bicarb is pretty low. The osmolality 357 million, small, spore kilogram of water. That's pretty high as well. This person has increased our serum osmolality, osmolality, right? And then we look at the AB Gs, the PO 275. That's low. The PCO2 is 26. That's low. The pH is 7.09. That is extremely low. The bicarb is 9 million equivalent per liter. That's extremely low. All right. And then we look at the urine. It's the urine. What do I see in the urine? Well, nothing crazy major, right? And then he says, which of the following is the most likely explanation for these data, right? So this question has a lot of quirks, twists and turns, right? So option A says alcoholic, you know, as he does, option B says, that very kiddo acid doses, option C says, I so purple alcohol intoxication, right? Option D says methanol intoxication, option E says salicylid intoxication, right? So let's do some teaching here. I think this is going to be one of those podcasts where we don't make it all the way to 40, right? Because I don't want to rush my way through these things. I feel like there's a lot of helpful teaching that I can do here. So I'm going to do the helpful teaching, right? But basically number one, I would not pick any of the options, right? Don't get me wrong. Those things can cause a metabolic acid doses, right? But when those things cause a metabolic acid doses, right? Look at even the names, kiddo acid doses, kiddo.

So alcoholic kiddo acid doses, that beddo kiddo acid doses. First things first, this person has three ski tones in the urine. The person is not ketotic, right? So we can cross off those answers. But also this person in this question, look at the blood glucose. The blood glucose is 121, right? And this person's urine is negative for glucose, right? So that tells us that this person is not in some kind of diabetic emergency. So that's wrong. So a and b are certainly wrong. I saw purple alcohol intoxication. Yeah, that could cause a metabolic acid doses. But again, I just feel like there is more information that goes with option D here than others, right? So I'm going to go to option D and here's why, right? So methanol remember can be converted by alcohol dehydrogenase to form out of height. And then that form out of height can be oxidized further, right? By as a touto high dehydrogenase to carboxylic acid in this case, formic acid, right? From out of height is not very good. We use it to fix biological tissues. I don't think that's something you want hanging around in your body, right? So that's part of why we use for mepazole. Right? For mepazole is an alcohol dehydrogenase inhibitor. So you don't form those toxic metabolites of methanol, right? So so methanol falls from out of height, right? And methanol, it can cause an optic neuropathy, right? It can mess up your optic nerve, right?

In fact, I think I read this back in the day when I was digging oak emin college from like my textbook is like some oak emin textbook, like some green oak emin textbook from back in the day. And I remember reading that, oh, that if you have, if you take us little as I think 15 milliliters, so 15 ml of methanol, that can cause blindness, right? So we see this person having like macular hypercharid macular, right? So the macular is being affected, right? Methanol can affect the macular. You see the ems match methanol for the macular, right? So that can cause blindness, right? So I would not, I would not ignore option D. Option D is the right answer here, right? I remember methanol is one of these organic alcohols, right? So it can certainly cause a presence of a metabolic acidosis for some good option D. Now, I know some people may be like divine. Couldn't this be salicylite intoxication? Well, no, right? No. So how does salicylite intoxication present? Well, first things first, you're going to have two things operating at the same time, right? So salicylite is derived from salicylic acid, right? So the person is going to have a metabolic acidosis, right? So the bicarb is going to be low. Okay. We have that here. But also salicylate can cause hyperventilation, right? So it can cause you to have a respiratory alcoholosis because you're blowing off your CO2. So yeah, the CO2 is low here. So you're like, oh, okay, divine. All right.

This checks off the boxes for salicylite intoxication. But why is this not salicylate intoxication? Right? So salicylate intoxication causes a metabolic acidosis and a respiratory alcoholosis at the same time, right? Now, the thing is when you have that happening, the thing that's going to happen is that it's almost like that alcoholosis and the acidosis balance out. So the person's speech is going to be roughly normal. I'm going to say that again, the person's speech is going to be what roughly normal, right? So I'm not going to pick that because this person's speech is down in the dumps is 7.09. It is nowhere close to normal at all, right? So I'm not saying that when you have salicylate toxicity, your, your pH will for sure be normal. No, it won't be normal. It will be a little bit. Usually it's going to be in the acidotic range, you know, but it's not going to be so low that it's 7.09. So I'm not going to pick that answer. I'm not going to pick that answer. Right? So I'm pretty sure that for this one, I feel pretty confident that the right answer is going to be option D. And also the, the, the eye problems, right? That kind of tells us everything we need to know, right? So I think I'm going to go ahead and stop here because again, the, the questions in this series, you know, I feel like sometimes you see this in these free 120 or whatever series you, you, you meet a question that is like, Oh, pretty, pretty high yield. A lot of teaching you can do.

Um, so I think I'm going to go ahead and stop here for this one. Or you know, let's do 36 real quick. So 15 year old African American girl comes to the ED because she says something has been sticking out of my bottom since I had a bowel movement this morning. She has not had previous episodes, although for more than one year, she has had occasional difficulty passing tools. She is not in pain, but is afraid to move her balls for fear that the problem will worsen. She tells you that she moved away from home more than a year ago and that appearance contributed nothing to her support. She has a six month old child and lives with a 28 year old female cousin. She has never been married and does not work or attend school. She has no other symptoms in order to follow the correct procedure for a trillion of minor, which of the following is the most appropriate step prior to evaluating this patient's rectal problem. Um, option E says accept the girls consent as sufficient be says obtain a corridor permitting evaluation. C says obtain the written consent of at least two licensed physicians. Option D says obtain a written consent. From at least one of her parents option E says obtain a written consent from a 28 year old cousin. I'm going to go to option A here, right, which makes sense, right. This girl is emancipated. If you're living on your own, you're providing for your needs, right? You're not living with your parents, you're providing for your needs.

Um, then you're emancipated when you're emancipated as a minor, um, you don't need parental consent, right? So again, emancipation, you're living on your own, you're providing for your needs or you're in the military as a minor, uh, you are definitely emancipated, right? So, uh, the girls consent is going to be sufficient, right? The girls, you don't need the causing of the parents or two physicians or whatever. Like why do you need to visit two licensed physicians to permit you to examine a child's rectum, right? So that, uh, a minor's rectum, that doesn't really make any sense, right? So the right answer is going to be option A. All right, so I'm going to go ahead and stop here, uh, again, if you like the way I teach, make integrations, you're going to love my classes. You're going to absolutely love my classes. Um, I actually have a 20 hour step two, step three class that is starting this evening, right? So if you're interested, you can still sign up. There is still opportunity to sign up. It's a great class for people studying for a step two, studying for a step three. Or if you ever studying for your shelf exams, especially like a big shelf exam, like your internal medicine shelf or your family medicine shelf, right? You're going to really like the class. It's going to give you like a very solid overview of many high-yield things, right? And again, it's not just me throwing associations at you, right?

It's me teaching you concepts, making integrations, explaining pathophysiology, showing you how to contest these things on exams, right? And remember besides that, I also teach other classes, I have like a 50 hour class for step two, step three. That's only going to be held once this year coming up in the first two weeks of June of this year. And then I have a last minute review also for step two, step three. I have those taking place. I have that in the month of April. And then other classes have in the month of April. I have a bio-stats class for step one to three, social science, ethics and QI class for step one to three, and a test-taking strategy class also for step one to step three. And they're all over Zoom. I'm the one that teaches those classes. And so again, I think many people do find these classes to be very helpful and they do pretty well on their exams. And then also, I hope we're one-on-one tutoring for all the USM Lian complex exams. And I help with ERAS applications. You know, we've pretty much studied another ERAS season. You know, mock interviews, personal statements and things like that. I help with all of those. So shoot me an email if you want any of those. And again, remember these podcasts are on Apple Google on Spotify. And I have a You Tube channel. You can also check out where I post the videos that I make. And then I have another website called divineinterventionlifelessons.com. Divineinterventionlifelessons.com.

You know, many of you know I'm a Christ follower. Every day, every week, sorry, every week, I post like one or two podcasts where from a biblical perspective, I address a life lesson. There's actually almost 400 episodes on there. Divineinterventionlifelessons.com. You can actually find the Apple podcasts associated with it. It's called the Divineintervention Life Lessons podcast. So thank you for listening to me today. I will see you God willing in a episode of 643, I think. Right? And we're going to pick up from where we stopped and keep going and keep learning. All right, so have a wonderful day. God bless you and bye for now. Thank you.

Embolism formation due to blood stasis/turbulent flow within the enlarged vessel wall.

Alcohol is a potent inhibitor of REM (Rapid Eye Movement) sleep, leading to fragmented and non-restorative sleep.

Optic neuropathy or macular changes (cherry red maculae).

The girl's own consent.

Ensuring adequate caloric intake, often achieved by prescribing hypercaloric formula (e.g., 24 kcal/oz).

Methanol intoxication.

Formic acid (formyl formate).

The patient's own consent (emancipated minor).

Consistent weight gain.

Salicylate intoxication (mixed acid-base disorder).

Methanol intoxication.

Formic acid (formyl formate).

The patient's own consent (emancipated minor).

Consistent weight gain.

Salicylate intoxication (mixed acid-base disorder).