I have a case study that I want to share with you. It’s kind of advanced. If you are an advanced thinker, you’ll enjoy this one. When I first started in medicine as a physician assistant I was a fast track PA and I had a doc right there; I showed him 100% of my EKGs. I evolved into a critical access PA. I’ve run hundreds of codes and taken care of wicked sick people and that’s what I do now.
Here’s the case. We’ll think through it together and I’ll talk you through it. I’ll give you a solution to this case. However, I challenge you to think independently about it first.
I came on shift, and I was signed up for hyperglycemic 22-year-old female. When I talked to her, she said, “You know I just forgot to take my insulin; I didn’t get my insulin.” She has a bunch of excuses, but she came in with very high blood sugar. That was her chief complaint. Labs were ordered and I had a bunch of other things going on. So, when labs finally came back and there was a little bit of a quandary, some curiosity to her labs and also with her presentation.
When I initially went in the room, I asked, “Do you drink alcohol, smoke or do drugs?” Her response was really inflammatory. She started yelling at her mom, “Mom don’t say a word!” She starts cussing out her mom, and I was like, okay, there are some interesting dynamics here, but she said the night before she went out and had some drinks.
I also asked, “Have you lost any weight or gained any weight?” I asked that because I was a little concerned about her emotional profile, how she talked to her mom. She said she’d lost about 15 pounds in the last six weeks. I said, “How are you losing weight?” My concern was an eating disorder of some kind, where she was purging, possibly making herself vomit or have diarrhea. She denied that. But her labs came back very curious.
At one point, as labs were cooking, she became very theatrical, complaining of chest pain. I went in the room and she was breathing fast, up in the 20-30 range. She almost seemed hyperventilating but complained of this diffuse-like chest and abdominal pain that, again, was a little peculiar. She was creating quite a scene in the emergency room, so it demanded my immediate attention. Again, I’m looking at her, and I don’t know if she’s sick, or if she’s being theatrical with her mom there. Just weird.
Her initial labs came back and her blood sugar was 333, her bicarb was less than five on a venous specimen, her potassium was 2.5 and her calcium was three. Okay. She was anemic, H and H was approximately nine and 27. I was able to compare this with labs from three months ago where her potassium, at the time, was normal, her calcium, at the time, was nine. So, once again, her calcium today is three. She wasn’t this anemic. She was normal acidic, but she was normal acidic months ago. Her H and H then was approximately 12 and 36, so it was a significant drop in the last three months. Now, because of her bicarb being less than five, I ordered a blood gas. Her PH came back at 7003, very low bicarb and very low carbon dioxide.
I’m looking at all of this going, “What’s going on with her?” Now, she sure looks like she’s in a metabolic acidosis. There’s no question she is. Her PH is low. So, she’s in an acidotic state and with her fast breathing, she’s Kussmaul breathing. Everything is consistent with a metabolic acidosis and, she kind of smells like DKA, but her blood sugar of 333 doesn’t make any sense. It doesn’t make any sense at all because I expect anybody in DKA to be hyperkalemic, not hypokalemic. And what’s going on with the calcium?
Again, I’m thinking about her emotional state and her possible loss of weight. Looking at potassium this low, her initial EKG did not show anything that make me think there were real drastic aberrancies with her electrolytes. Her T wave was up right, her QT segment was fine. So, I didn’t find anything on the EKG that had me immediately alarmed.
My question is, what would you do with this case? How would you approach it? How would you treat her electrolytes? What would you do with thie PH of 7005?
This was one of the more challenging cases I’ve taken care of in a long time, so I wanted to have you think about this. Adults learn best by active engagement teaching, just like this case study and my live courses. In our self-assessment program, we ask questions, you respond and we talk about cases. You critically evaluate a situation, then you get feedback. That’s what I want to do with this case study.
I know this case is advanced and so is the way I’m asking you to think about it. If you’re new to medicine or this isn’t really in your wheelhouse, you can still guess and throw out ideas.
Answer:
This is the end of our case study on our patient who is acidic and hypocalcemic and hypokalemic. Now, when I first saw the potassium of 2.5 in a young lady, who three months ago had normal levels of potassium… People handle potassium relative to their baseline. So, if you have someone who’s chronically in renal failure, they’re going to do okay with a potassium in the high five range. They probably live pretty close to that.
Hyperkaliemia or hypokaliemia is really relative to the patient, and how much it’s going to affect them. The mainstay to know if it’s really bothering her cells is her EKG. Now, her EKG was normal, but with a potassium of 2.5, I initially ordered IV fluids with potassium; you can run up to 10 mil equivalents per hour in an IV. I ordered a liter saline with 40 mil equivalents potassium, running at 250 ccs an hour. I ordered that, but as I’m looking at it, this does not make any sense.
Anybody in a metabolic acid dosage is going to be hyperkalemic, based on hydrogen ions being very high in the blood. The body freaks out at that, so it sucks the hydrogen ion in the cell. In return, the body spits out a potassium. The only exception there is aspirin overdoses. But this doesn’t make any sense, and why would her calcium drop so drastically low? Now, I embrace being a physician assistant. I embrace not knowing sometimes., I’m humble with my education and my role; I call it an IE ratio. That’s intelligence to ego ratio.
If your IE ratio is in proportion, you know when to ask for help. I’d like to think that I have my IE ratio in proportion. I had to call another hospital where there’s a board-certified ER doc who was supervising doctor. I had to run this case by him, say, “Listen. Something’s not right here, and I don’t know what it is.” He said, “John, read me all the labs.”
So I read them all to him. He said, “Redraw your labs. This has got to be a dilutional blood sample. Someone had to have drawn blood upstream from an IV.” I redrew the labs, and her blood sugar was in the 700 range, her potassium was high, calcium was normalized. Her anemia, and I did a rectal example on her too, it would be positive blood, because it was dilutional.
Bottom line is, this was such a silly mistake on my part. You know, any time labs are drastically off, recheck your labs. Any time things just don’t seem right, redraw it. The bottom line is, I was red herring.
Now, a red herring used to be when bloodhounds would try to track a criminal. The dogs would follow the person’s scent. The chase would end up at a creek where red herring, a big kind of fish, would wash ashore and die. The criminals would grab the red herring and drag it off to the side so that the dogs would follow the fish and not the criminal, or the person they were after.
I got red herringed by her emotional state and the fact that I thought she may have been inducing vomiting, inducing this electrolyte disorder.
This was almost a very big mistake. I did order the potassium, but before I gave it, I talked to the supervising doc, who said, “John, you got a dilutional specimen.” I’m very humbled by this, and I just want to make sure that you guys don’t make that same mistake. And I’m just going to say, if things don’t make sense, confirm it, recheck it. Okay? Before you drop a bomb, before you drop a bomb on someone, like they have cancer or diabetes, double check it. Because I’ve made that mistake, too.