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USMLE War Jounral: 23 Days After Test Day

First of all, it is ridiculous how long they make you wait for Step 1 scores, not to mention how hard it is to find out when your release date will be.

That being said, I cannot believe it took 23 days to find out.  For 23 days, I have held my breath.  The test left me feeling really crappy and I imagined some below-predicted performance.  Last week at 16 days post-test, all results for tests up until June 22 were released.  Some of my friends found out they had passed and I was happy for them.  I also gave up on being apprehensive.  My time off was only winding down and I was not going to let anxiety get in the way of enjoying my time off.  I went out more frequently with friends, got through more of the book I am currently reading (Genius on the Edge by Dr. Gerald Imber on the life of Dr. William Stewart Halsted, the father of modern surgery).  Still, it felt awkward trying to do things toward my career and I even shied away from writing more on the subject.

I found out that my score would come Wednesday, July 18.  This morning, I rolled out of my futon to my computer.  My school was going to have my results posted before the NMBE posted my score report.  I clicked through the menus to the appropriate screen to find the three-digit number that would matter more to me than any other three-digit number in my life. 

238

I had passed.  And comfortably, too.  For those who do not know, the cutoff is 188 and the average usually hovers around 220 year to year.  The standard deviation usually hovers around 20.  I was satisfied.  I knew this score would be fine for my intended field (internal medicine).

I spent the rest of the day in unremarkable celebration.  I went to the comic book shop, treated myself to a beer with dinner, and watched the second part of Che which I had started the night before.  I texted all my friends from high school who had been supportive throughout the last couple weeks and called my family and medical school friends.  For now, its too early for complete reflection on all my methods and the advice I recieved.  There likely be another post on that in the future.

Elsewhere in the world, things were getting crazy.  The hottest summer in a long time was having what was likely to be a low point at 85.  On the radio, the crisis in Syria was escalating.  Later I read an article on how Rush Limbaugh tried to argue that the new Batman movie was an anti-Romney film because of the similarity in sounds of the name Bain and Bane.  Little did he know, Bane was created in the 90s, well before anyone really gave a damn about R-Money. 

USMLE War Jounral: 1 Day Until Test Day

Last week I tried to make a video post since it was my last week at home.  Obviously, that didn't work so I am back to the tried and true written word. 

Saturday I came up to my parents house since my test is in Strongsville.  I did not get much done (as anticipated) but I get all of today to myself to casually just review stuff.  It has not started great, however.  See, for the past couple years, I actually do not sleep in my old room at my parents because I seem to get a real bad sinus allergy.  The pillows are different than the other ones in the house and I think that I am allergic to something in them.  True enough, I woke up real early today to sneeze.  I could not use the guest room last night because my brother's girlfriend and her siblings came over on their way back home (they live quite far from where my parents' home).  I have never been woken up by allergies before and I hope I can get the basement to myself tonight.

Because tomorrow is the big one.  Various movie quotes from before epic battles have been running through my head.  I cannot wait to be done.  My plan afterwards is to walk over to the sports bar next to the testing center and eat hearty.  And drink beer, too.  After that, July will be mine. 

USMLE War Journal: 15 Days Until Test Day

At this point, my fellow medical students and I have been out of classes for about 19 days (which seems unbelievable).  This week I noticed a lot of my colleagues starting to wear down but many seemed to have anticipated this and cope in their own ways. 

Here are two more sketches from the past couple weeks.

This first one is my version of my school's old logo.  Since my school has changed its name and logo I really do not think (and hope) that there are any problems with me posting this.  At the very least, I have only good things to say.  I was a really big fan of the old logo from a graphic design standpoint.  Symbolically, it told you every thing you needed to know about my school.  Like any good logo it had seen some slight changes throughout its use but it was still recognizeable.  Mine does the same in making some slightly different design choices.

This second one is a sketch of the superhero Dr. Mid-nite after the famous painting The Doctor by Luke Fildes, which I have wrote about before.

Step 1 Art: My Tribute to the Original Orignal Green Lantern and his Children

This is the first of many just-for-fun sketches I've done in my spare time to do something creative during Step 1 studying.  There's quite a bit into why I decided to draw the characters I did.  A couple days ago, DC Comics announced that in his new incarnation, Alan Scott, the original Green Lantern, would be gay.  As a big fan of Alan Scott and the JSA in general, this has been one of the most bothersome of the changes at DC Comics. 

It's not that I have anything against gay people.  In fact, I have many gay friends and I am a fan of many gay fictional characters.  As a matter of fact, Todd Rice aka Obsidian, Alan Scott's son (the blue guy on the left) is an openly gay character from the old DC.   

What bothers me is DC's discarding of Alan Scott's rich, albeit more obscure, 70-year-history as a DC character and the work of the writers and artists that helped make that happen all for what is nothing more than a publicity stunt.  In the preceding weeks before the announcement, DC teased that they were making an "iconic" character gay and there was much speculation on who this might be with names like Tim Drake (one of Batman's Robins) and Wonder Woman thrown around.  But when it was annouced that Alan Scott was the character that was coming out many including myself have felt it is the king of all cop outs.  Sure he is a Green Lantern but he's only really known in comic circles these days so most people are probably just as confused when it was announced that Miles Morales, a Afro-Hispanic-American, would be the new Ultimate Spider-Man. 

While I do appreciate DC trying to be progressive, it feels that the LGBT movement has been undermined to generate more publicity for itself (a common theme lately).  I doubt sales this week will be that much more increased or gay readers will be more drawn to DC titles.  So the victims of this little marketing ploy?  Just the original Alan Scott and, until some comic book universe tweaking occurs, his kids Obsidian and Jade.  If you knew the old Alan Scott, you probably enjoyed that everything about him was old.  I mean, his costume for most of his history has been a red shirt tucked into green pants with a cape!  However, the other DC characters respected him as a veteran.  He represented that Golden Age morality that is impossibly forthright and good and survived for 70 years despite the changing of the times.  And maybe it's appropriate that such a character is retired now but I really would rather he was still around. 

USMLE War Journal: 22 Days Until Test Day

Well this last week started off great and by great I mean I had a low-grade fever for three days.  Next time I am going straight to acetaminophen.  NSAIDs just wouldn't keep the temperature down long enough.  It was not really a preference thing - I was just hoping to treat myself with whatever I had laying around the house.  On day three, I gave in and went to go buy some acetaminophen. 

This is exactly the sort of unexpected thing I anticipated when I built in leeway in my schedule.  There were times where I couldn't power through anymore and had to lay down.  It seemed the more I tried to do board studying, the higher my temperature got.  What made it worse was I had terrible sleep those nights.  I got up every two hours it seemed.  Unable to exercise due to illness, I found myself a little depressed from not having some kind of non-academic outlet.  Watching TV is a little too passive for me and sometimes I am not in the mood to read (although I did read a ton of comics while sick).  The past couple days, I started drawing again, mostly superheroes.  I am not a a particularly amazing artist or anythign like that.  My own honest assessment of my own work is that it is a slightly above average amateurish style.  But it did give me something to do.  When I finish my first one I might upload it.  My second one is my own take of a classic medical painting.         

USMLE War Journal: 29 Days Until Test Day

So I have been studying for my board exam for just under a week and I have set up Sundays to be kind of a free-for-all day.  I can catch up on stuff if I am behind on my schedule, hit harder on stuff that has been giving me trouble, do chores, etc.  I must confess this was not an original idea of mine but I like building in flexibility when I make schedules. 

I've also scheduled in time for myself at the end of every week day.  I study pretty much from 8 am to 6 pm everyday and then give myself most the rest of the night for dinner, a workout, even reading and tv.  Before bed, I like to go through cases or quiz myself on stuff I need work on.

For my question bank, I use USMLE World, probably the best bank out there.  After two years of medical school, I have (amazingly) a good working knowledge of the medical science out there but what the question bank is good at is helping me hunt down all the little details I may have overlooked and need to pick up on.  First Aid is good but even it does not have all the answers sometimes (although I do have the 2010 edition).  This week alone I already ran into a few USMLE World questions that had no/inadequate information on certain topics like JAK/STAT pathways and direct factor Xa inhibitors (a relatively new class with rivaroxaban as the only FDA approved one currently; older drugs such as fondaparinux have also had Xa inhibitory action).         

In First Aid's defense, there is a ton of information out there and the majority of it has been miraculously summarized into one volume.  Medical information alone is always changing as well.  I cannot even remember all the times I was tested on a current guideline for screening just to hear it get changed next month.  I have begun to wonder how much the USMLE itself has changed since its creation.  Perhaps I will investigate this after I take my own test.

UPDATE: As soon as I finished writing this I got an update on my phone about the US Preventative Services Task Force recommending against using PSA screening for prostate cancer.  They suggest physicians discuss the reliability of PSA with their pateints.  They also admitted we don't have any good tests at the moment for prostate cancer.

The Killer Croc Differential

So today was the first day of dermatology lectures at my school.  I've never been that enthralled with the subject.  So I decided to do a little independent reading on dermatopathology and thought of (as usual) a comic book connection.  Perhaps one of the most famous comic book characters who has a skin condition is Waylon Jones aka Killer Croc. 

Okay, purported to have a skin condition.  But that's what I like about the Killer Croc character, his exact origin is still shrouded and unclear which fits with his status as an urban legend come to life.  Hopefully, it stays this way (I hated when Wolverine's origin was finally established - it was always more interesting when it was left to speculation).  In the couple decades he has been around, there have been numerous depictions of Killer Croc as well as explanations of his condition:

Killer Croc designed by Bruce Timm for Batman: The Animated Series

1. Atavism - a sort of evolutionary reversion.  In real life, this is seen as people with supernumary nipples, large canine teeth, or vestigial tails.  Depending on which depiction you follow, Croc is a mild to very dramatic example of atavism. 

Killer Croc as depicted by Lee Bermejo in Joker

2. Epidermolytic hyperkeratosis - a rare skin condition where the skin blisters and scales.  I am not quite sure where this first showed up in Croc stories but it was definitely featured in Batman: Gotham Knight, the animated tie-in to Christopher Nolan's Batman universe.  Again, Croc would be a pretty dramatic example but I like the possibility that Croc can be medically explained.

Killer Croc in Batman: Arkham Asylum
Designed by the folks at Wildstorm with obvious reference to
Jim Lee's design from Batman: Hush

3. Just a mutation - the comic book fall back explanation for anything real messed up.  Mutants are not featured as much in DC Comics as compared to the Marvel universe (Stan Lee always wanted semi-scientific explanations for his characters and stories) but Croc could just have mutated to be reptilian-like.

My Favorite Board Question

I've been studying almost all week during my spring break and it made me think of this question which is pretty well known among medical students.

Why Studying for Boards is Going to be so Much Better Than Studying for Classes

These are the changes I am welcoming in about a month (yikes!)

1.  I can stay home.  My spending on gas is going to be at least half of what it is now. 

2.  I can keep things interesting.  Usually I am mentally checked out after about the second or third hour of lecture unless a really good lecturer is going to talk.  I definitely plan to go through multiple subjects daily so that I don't get tired of the same subject all day.

3. My leather chair at home is a million times more comfortable than anything I ever sit on at school.  'Nuff said.

4. Dr. Edward F. Goljan.  Do I really need to explain this one?

5. My one job everyday is going to be studying for boards.  All other demands on my time are going to be suspended and my purpose is going to be singular... sexy. 

Sail Through Acid-Base Disorders with Your ARMADA.

A third year friend shared this approach to acid-base disorders with me so I thought I'd share it since they can be problematic at times.  It centers around the mnemonic ARMADA which stands for:

A = Acidosis or Alkalosis?

R = Respiratory acidosis/alkalosis?

M = Metabolic acidosis/alkalosis?

A = Anion gap

D = Delta gap

A = Assess for appropriate compensation

Okay so let's work through an example to show you how this can work.  Here are some numbers:

PCO2 = 35 mmHg
[HCO3-] = 18 mmol/L

Now you are often given the pH on labs but in the event you do need to calculate it the Henderson equation (Henderson with out the "hassel") is quite useful:

[H+] will be given in nmol/L so you can either take the -log[H+] to find pH or you can try to memorize a few correlations on this table to get a good estimate of the pH.

Recall that physiologic pH is 7.4 and that, interestingly enough, correlates with a [H+] of 40 nmol/L.  For every 1 nmol/L increase in [H+] from 7.4, pH decreases by roughly 0.01 and vice versa. 
Anyway, our example has pH 7.33.

Other important labs to pay attention to are Na+ and Cl-.  For this example:
Na+ = 136 mmol/L
Cl-= 98 mmol/L

Okay on to ARMADA. 
A - Is the patient in acidosis or alkalosis?
With a pH of 7.33 this patient is acidotic.

R - Is this patient in respiratory acidosis/alkalosis?
PCO2 is slightly decreased from normal (40 mmHg) which would cause an increase in pH (more basic).  So this patient is not in respiratory acidosis.

M - Is this patient in metabolic acidosis/alkalosis?
HCO3- is below normal (24 mmol/L) which would cause a decrease in pH (more acidic).  So the primary disorder here is a metabolic acidosis.

A - Anion gap.
This only really applies to situations of metabolic acidosis.  To calculate the anion gap we are using the formula:

AG = Na - (Cl + HCO3).

A normal anion gap is no larger than 12 mmol/L.  Our AG = 136 - (98 + 18) = 20 mmol/L.  So we have an anion gap metabolic acidosis.  This means we can narrow down our causes of the acidosis to a handful of situations where an unmeasured anion has a signifcant presence in the body.  The classic mnemonic for this is MUDPILES.

What if the anion gap had been normal?  Well then that would typically mean a loss in one of the measured ions such as bicarbonate loss in diarrhea or renal tubule acidosis and often chloride anions increase to counterbalance the loss of HCO3 (hyperchloremic acidodis).

D - Delta gap. 

The delta gap will tell you if there is more than one process is going on alongside a anion gap metabolic acidosis.  It is calculated as follows:

or simplified will read

Essentially, we are seeing how much does the loss in bicarbonate match to the increase in acid. 

If the delta gap is between 1 and 2 there is probably no other process going on. 

If the delta gap is less than 1 then there is an additional normal anion gap metabolic acidosis (more bicarbonate lost than one would expect)If the delta gap is greater than 2 then there is an additional metabolic alkalosis going on. (less bicarbonate lost than expected).

If calculate the delta gap for our example patient we get 1.3.  There is probably no other issue going on.

A - Assess for appropriate compensation.

Now to check for compensation. You can memorize much easier things than formulas and it makes sense conceptually.

·         Normal P_CO2 = 40 mmHg

·         Normal serum [HCO₃^-] = 24 mmol/L

·         The ratio of change between the two parameters, which I summarize and simplify in my own tables below

*Note I am purposely ignoring 2 things for now: 1) +/- direction of the ratio because I think it is more important to think of the direction conceptually (later on).  2) the margins of error because I think we should normally allow for slight variation anyway. 

Respiratory acid-base changes and ratios of compensation (i.e. “for ___ increase/decrease in P_CO2 there is a ____ increase/decrease in [HCO₃^-]”)

	Δ[HCO3]/ΔPCO2
Acute Respiratory Acidosis	1/10
Acute Respiratory Alkalosis	2/10 or 1/5
Chronic Respiratory Acidosis	3/10
Chronic Respiratory Alkalosis	4/10

Metabolic acid-base changes and ratios of compensations (i.e. “for ____ increase/decrease in [HCO₃] there is a ____ increase/decrease in P_CO2)

	ΔPCO2/ Δ[HCO3]
Metabolic acidosis	1.2
Metabolic alkalosis	3/4

Ok so how are we going to use this?  Here’s an example with acute respiratory acidosis.  Respiratory acidosis is caused by an increase in P_CO2 so let’s say that someone has a P_CO2 is 60 mmHg so that means ΔP_CO2 = 60 mmHg – 40 mmHg (normal) = 20 mmHg. 

Now we use our ratio.  For acute respiratory acidosis Δ[HCO₃]/ΔP_CO2 = 1/10 so that means we can find the change in Δ[HCO₃] by taking (1/10) ΔP_CO2 = 2 mmol/L.  

So we should expect a change of 2 mmol/L from the normal [HCO₃^-].  Is it higher or lower?  Well in respiratory acidosis we would want to increase HCO₃^- to compensate for the increase in P_CO2.   So that means we add 2 mmol/L to the normal [HCO₃^-] (24 mmol/L) which means we would expect a [HCO₃^-] of 26 mmol/L.

Now let’s do one with metabolic acidosis which is what our example case actually has.  When we use the numbers for our case we get Δ[HCO₃] = 24-18 = 6 mmHg. 

Use the ratio and we find that we would expect a P_CO2 change of 1.2 x 6 = 7.2 mmHg. 

In metabolic acidosis we would expect a drop in P_CO2 to compensate so 40 – 7.2 = 32.8 mmHg is our expected P_CO2.  Assume a fudge factor of +/- 2 and we are pretty close to 35 mmHg so our patient is appropriately compensating.

Now, that being said, First Aid does go out of their way to provide the same formula we were provided in class for metabolic acidosis compensation.  This is Winter’s Formula and I confirmed with an third year student that this is the one to know for sure:

P_CO2 = 1.5[HCO₃^-] + 8 + 2

If we use Winter’s formula for the example I just gave we get P_CO2 = 1.5[18] + 8 + 2 = 35 + 2 mmHg.  Pretty damn close.  Two tools for the same job (like the MacIntosh or Miller blades for intubation), decide which you like better.

What if the numbers did not match up?  Well that would mean that the patient is not appriately compensating.  In real life this could mean a number of things depending on your case situation.  I worked up an example one time where the patient was not appropriately compensating her metabolic acidosis because she was going into respiratory failure and could not blow off enough CO2.  Likewise, I could see a situation if a patient was losing too much bicarbonate when it needs to be retained for compensation.

Hopefully, this was useful to my fellow medical students.  Good luck studying everyone!   

                                              

Pharmacy Review with Trollface - U Jelly?

For some reason, I have had trouble remembering the mechanism of action of metronidazole.  When I looked it up for the millionth time it finally dawned on me: metronidazole basically trolls bacterial proteins making them inactive.  A friend at le med school has been showing me a bunch of Troll Physics cartoons lately so I whipped up some "Troll Medicine" in about fifteen minutes:

And now I am never going to forget how metronidazole works or what it is used for.  U jelly?

Haven't posted in a while.  This video was shared with me by a friend.  It is a hilarious and very accurate take on medical school lectures.  Thanks to those at Washington University in St. Louis for making this.  It was a relief to know that the plight of medical students is universal.