Hyperglycemia Workup for New Nurse Practitioners
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Show notes:
How do you know if someone with a glucose of 500 needs to go to the ER or can be managed outpatient?
Continuing on the lab interpretation series, today's video is all about knowing what to do, when to do it and resting at night knowing you haven't missed anything.
It's much simpler than hyponatremia (phew!) and I'll bring you through the checklist you need to manage patients like this.
Managing High Blood Sugar in Primary Care
Using a case study format, you'll learn:
How to know when your patients needs to go to the ER, and when you can work them up outpatient
The worst case scenarios for high blood sugar
The two-step process that’ll keep you grounded (it’s easy to remember)
Want to Build More Confidence Interpreting Labs?
If you found this case study helpful, you'll probably enjoy the Lab Interpretation Series.
Inside the series, we take the same practical, case-based approach to interpreting common primary care labs—but go much deeper into the clinical reasoning behind them. Rather than memorizing reference ranges, you'll learn how to recognize patterns, work through differential diagnoses, and apply lab results to real patient care.
The Lab Interpretation Series includes self-paced, ANCC-accredited courses covering CBC, basic metabolic panel, renal labs, liver function tests, thyroid labs, hyperlipidemia, and more.Learn more about the Lab Interpretation Series →
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Liz Rohr:
Well, hey there. It's Liz Rohr from Real World NP, and you're watching NP Practice Made Simple, the weekly videos to help save you time, frustration, and help you learn more faster so you can take the best care of your patients. So today I'm going to be continuing on the lab interpretation series with high blood sugar. So this is a really common question that I get. And this question in particular comes from Laura. So Laura was asking me if you have a patient with high blood sugar, like a glucose of 500, sometimes I see providers sending them to the ER. And then other times I have people who keep them in outpatient management and it's totally fine. So how do I know the difference?
So in this video, I'm going to really break it down into two main steps. You'll be able to safely say whether or not somebody can be managed outpatient, or if they need to go to the ER. That is my goal for this whole video. So I'm going to be introducing another case study that if you've been following along, you've seen him before. His name is George. Not his real name. But he had high potassium hyperkalemia. So if you haven't watched that video, you can definitely check that out, but I'm going to be doing a recap as well. So without further ado, I'm going to share my screen with you.
Okay, so this is the hyperglycemia case study. So this is George. He's a 63-year-old man. He has diabetes and he, at this visit that I'm going to be referencing, is re-establishing care. And so if you've been following along, you've already seen George. But if you haven't, I already talked about him in the video about hyperkalemia, high potassium. And it's a complicated case, so I think that it's worth revisiting, not only because it's an excellent case of high blood sugar, especially in the federally qualified health center setting, which is where I work, which has its own caveats and challenges that you don't necessarily see other places. But also, I think that it's worth cementing the other topics that we've touched on.
So if you want to take a look at that video, I'll link to it below. You can definitely watch it first, or you can watch it after you're done here, but I'm going to do a recap of the background. And again, this is not his real name or his photo. And I'll leave a timestamp on here if you want to skip ahead to after the case study if you've already seen this gentleman before.
So this is George. So first visit back from about a year ago, he was going consistently and then just didn't feel like coming for about a year. He's intermittently taking NPH insulin 70/30, 20 units twice a day. And he has a sliding scale of five units of novolog when he feels like it.
Luckily, he's a non-smoker. He drinks alcohol, a few beers here and there, those are his direct words. And past medical history of hypothyroidism. He has a remote history of CML that's in remission, luckily, and then he also has high blood pressure. So he has no known past surgical history or family history. His blood pressure is 150 over 90 at this visit. His other vital signs are normal. I don't have access to them. This is a former patient from a couple of years ago, so this is based on memory on some notes that I had had.
But anyway, his heart rate was normal. His oxygen was normal. He's taking levothyroxine 200 micrograms, and he had a year's worth of medications so he's still been taking it since his last time he was seen. He lives alone. He has no sexual partners. And he's on disability, so he's not working right now.
So the plan, today I'm going to focus on hyperglycemia, but I'm going to touch on the other components of holistic care at the end of this presentation. So I'm going to check some labs for him. I'm going to look at a CBC to see any signs of anemia or infection, CMP, I'm going to look at liver and kidney function baseline. I'm going to look at hemoglobin A1C to check on his diabetes. A urine microalbumin. This is a standard of care for diabetic patients to look for signs of early kidney impairment. And if you haven't seen that, that's what that is. And a TSH to check his thyroid function, and then cholesterol.
So here are his results. So they're not the prettiest things ever, but I'm going to break it down. So let's just look at the top here. It's CBC is normal, luckily. The cholesterol is high, which we'd expect. I don't have the full panel here, but we're not really talking about cholesterol today. So I'm going to leave that there. Urine microalbumin is also high, which correlates with his other blood tests. So I'm looking at a BMP spliced together with the CMP to keep it all on one slide.
So glucose is 572. That's super high. The BUN is 35. His creatinine is 2.19. So that's also super high. GFR is 32, which is low. Sodium is low at 126. Potassium of 5.8, which is high. Chloride, which is low at 88. And then the rest of the labs, calcium, protein, bilirubin, ALK PHOS, AST, ALT, luckily, those are all normal. So normal liver function, which is nice because he does drink a bit. I'm not sure how much, but he says just a few. Thyroid function, luckily, is normal. So it sounds like it's a good dose for him. And then the hemoglobin A1C of 10%. So I'm not really surprised by this when I get the results, just because he's not really consistently taking care of his diabetes for the history.
This slide is really important. So DKA and HHS. This is the worst case scenario of someone with high blood sugar, is being in the state of DKA or HHS. So that's diabetic ketoacidosis and hyperosmolar hyperglycemic state. And I know when I was in school, I was like, "I don't really get this. What is the deal with this HHS?" I don't know. I just didn't really understand it. So I'm going to get into it in just a second.
So just keeping in mind that those are the hyperglycemic emergencies, or DKA and HHS, and I'm going to talk about them in a second. So two steps to hyperglycemia. So you see a high blood sugar. What are your first two steps? Number one is safety. Is it safe to manage them in, excuse me, outpatient or do they need to go to the ER? And I'm going to give you some very clear-cut steps to determine what's safe and what's not. And then two, is to identify the causes. If you've determined it's safe to keep them out of the ER, their next step is to identify the underlying cause and fix that, because it's not just about treating the blood sugar, it's about figuring why their blood sugar is high.
So again, they are four points to determine if this is safe to manage this patient. And you might just only need the first two. So number one, how high is it? So normal range, the textbook lab results of 65 to 99. Typically less than 200 on a random would be ideal. So Type 2 diabetes, HHS, this hyperglycemic emergency, starts at 800 to a thousand approximately range. And the reason for that is it because if you have Type 2 diabetes, you have some insulin leftover. You would not completely bereft of any insulin. And so your blood sugar could feasibly get that high. And the reason it's so dangerous at that level is because your body's just trying to compensate to get rid of all of that sugar. And it's just not able to compensate anymore.
So Type 1 diabetes is diabetic ketoacidosis because there's no more insulin, and what it's doing is that it's processing fat instead of sugar. And that's making keto acids, which is very acidic in your blood, and that's pretty dangerous. And so it starts lower at around 250 to 400. Whereas in Type 2 diabetes with HHS, there's really not many ketones if at all. There's some ketones typically, but it's not as significant as in DKA.
I'm just going to do a side note here because this patient is a brand new patient to me at this visit, and he's totally taking insulin only. And so how do I know if he has Type 1 or Type 2 diabetes? And the complicated answer is, fortunately, that there's no set criteria and it's really based on some blood tests, as well as the big picture of a couple of different things. So labs, I've never ordered this, but you can order some pancreatic autoantibodies, not necessarily a hundred percent reliable. C-peptide and insulin I've seen ordered more often by endocrinologists. And C-peptide is a by-product of insulin production. And so if you're able to make insulin, you're going to have C-peptide, versus if your C-peptide is low, that means that you're not producing any insulin. And then insulin is just your blood level of insulin. But that's not necessarily that helpful if somebody's injecting insulin already.
So the other things to think about our family history, body habitus, age onset, usually younger, but can happen actually anytime in life, unfortunately, for Type 1 diabetes, family history, like of autoimmune disease, things like that [inaudible 00:08:21] as they tend to be smaller body habitus than overweight or obese. And then less ketones in Type 2 diabetes, again, because they still have some insulin.
So step number one, how high is it? Is it closer to 800 or is it closer to 250? What's the deal here? And do they have Type 1 or Type 2? What ended up happening for this patient is that I did a deep dive in his chart and I figured out that he was diagnosed with Type 2 diabetes, but something to keep in mind.
So in step number two, do they have symptoms? So Type 2 diabetes symptoms of the HHS can be insidious, meaning it's a slow onset of polyuria, polydipsia, and weight loss, of thirsty all the time, peeing all the time. Oh, excuse me. And then they also have neurological changes when it gets to be worse. So they can have lethargy, be obtunded, have focal neuro deficits, and that progresses all the way to coma. And the reason I'm writing those down and telling you them is because if somebody is in a coma, you're going to call the ambulance. You're going to send them to the ER. But I use this in counseling for patients when they're like, "I don't want to go to the ER. I don't want to do whatever you're telling you to do," just like a counseling measure, that this is kind of like the trajectory on which you're going, and this is why we need you to go to the ER.
So Type 1 diabetes can have abdominal pain. You've probably heard of that before, of high blood sugar causing abdominal pain. You don't see that as much with Type 2 diabetes. And then they may also have signs of dehydration on the exam. If you happen to see them at that visit and you check their blood sugar at that visit and it's high, which is not the case for this patient, but I'm going to get into that in a second.
But if they're complaining of symptoms, you check their blood sugar, and they had signs and symptoms of dehydration. So those, again, just to recap, are orthostatic vital signs, dry axillae, apparently. I did not learn that in school, but this is what I've learned after the fact, that that is a fairly evidence-based way to [inaudible 00:10:11] significant way to determine if somebody has low volume status. I don't know. I've never checked it, but I'm just telling you what I learned.
Mucus membranes, looking at dry mucus membranes that are cracked, cracked lips, and I think a fissured tongue and if they're tachycardic. Mucus membrane physical assessment is not necessarily super, super evidence-based. So if you have any questions or concerns about it, definitely make sure you're checking some labs too to verify their volume status. And tachycardia, orthostatic vital signs are a little bit more evidence-based in terms of statistically significantly showing that it correlates.
So the easy thing here is that if they are symptomatic, they're going to go right to the ER. Does not matter if they have a blood sugar of 200, if they have a blood sugar of 800. If they have symptoms and they have signs of dehydration, just send them to the ER. And no one's going to fault you for that, because you know what, this is about safety first. So a lot of the times you can just stop at safety number two.
It can be a tough judgment call too because some patients are resistant. Like I said, you can counsel them based on what you've found so far. But I'm going to talk in a second about management of those patients that aren't going to go.
So safety number three. So if you determine that they don't have to go to the ER, they're not really symptomatic or their blood sugar's not that high. :et's look at the other labs that will help us get a better idea of what we should do for this person. So, absolutely looking at the renal impairment, at their GFR status, that is going to tell you if you can manage them outpatient as well. So HHS and DKA, if they're actually truly in that state, that can cause acute renal impairment. And so if you have acute kidney injury, then they're going to be less likely to be able to filter glucose when it's impaired. Because that's how they're going to get rid of it. Aside from the treatment of giving them a way to process the blood sugar themselves, their body's mechanism is just to pee out glucose, and they're not going to be able to do that if they're impaired.
And so are there other electrolyte abnormalities? Because that's going to tell you how much is there going on here? Is it really just a high blood sugar and everything else on their plate is normal? Their kidneys are normal, their potassium is normal, their sodium is normal, all that stuff, then that's less of a concern. But if you feel uncomfortable and you see that there are also other electrolyte abnormalities, absolutely send them.
So safety number four is patient competence and understanding. And so is this a new or established diabetes? I say that because this patient has had diabetes for many years, and actually can recite to me very well how to take care of his blood sugar and his diabetes. He just chose not to do it. So he understands what he's doing. It's an established diagnosis. He has a glucometer at home. He has medication to take at home. And he has that, like I said, that health literacy, that understanding of how to take care of his own health. He just chose not to do it.
So in this patient case, I'll talk about in a second, but when you have that patient in front of you who has a high blood sugar, does not have symptoms and their labs are normal, are they able to pick up the medications that they need? Are they able to check their blood sugars? Do they understand how high and low blood sugar symptoms? They're going to be a good candidate to be managed at their house versus in the ER.
And you know what? If you send somebody to the ER and step one, two and three are totally fine, and it's just step number four that you're getting held up on, absolutely send them. And sometimes, I've gotten some not as nice ER notes back from patients that I sent to the ER for safety sake. And maybe they have some opinions about maybe they shouldn't be there. But honestly. You're giving the best care to the patient and that's what they need at that time. And hopefully, they get the treatment that they need to start. And that further reinforcement of making sure they're totally fine. That's the most important thing.
So the next step after you go through all those safety sets is to identify the cause. So most of the time, it's going to be non-adherence and missed medication. They have established diabetes and they're just not taking their meds because they don't want to. At least that's the patients that I see.
So underlying illness and medication are the other causes that you want to think about. So I'm not going to talk about adherence on its own slide because I'm sure you understand what that means. Underlying illness. So this is really important because if somebody is taking their diabetic medication, they're checking their blood sugar, they have not changed their diet and they're having a spike in their high blood sugar, you should have a ding, ding, ding, a red flag in your mind of what is causing this high blood sugar.
Because the reason is, an MI, a CVA, sepsis, pancreatitis, UTI, especially if you've got those geriatric patients that are not able to communicate as well, you're working in a skilled nursing facility, something like that, these are really dangerous things that are just hidden in there. If the story doesn't match up, but they're taking the medications, and they're checking their blood sugars, and they haven't changed anything in their life, absolutely make sure that they do not have those other things.
And if you're not sure, if you can't do a workup for an MI, a hidden MI, or you can't do a workup for their signs of infection, that's another reason to send them. And they're going to take it seriously in the ER, especially with an older geriatric patient with multiple comorbidities. And actually, if this is the first time that you've had a high blood sugar, sometimes this is a newer onset of Type 1 diabetes, which again, can happen at any time in the lifespan, typically happens in childhood versus, I think young adult is the other time, but just something to keep in mind.
So drugs. I'm just going to give you a list here because there are a lot of medications and it's not a hundred percent typical for them to cause it. But just so you know, beta blockers, crazy. They cause a lot of weird side effects of electrolytes. Calcium channel blockers, the same, super common medications. Chlorthalidone or other thiazides can definitely cause some high blood sugar.
This is what I see more often than others, I'm not going to say it right, Olanzapine, also known as Zyprexa, some people know it as that. Second generation "atypical" anti-psychotics. Those can definitely cause a metabolic syndrome of a high blood sugar. SGLT2 inhibitors, and a few other less common medications. So if you have an uncommon medication that you don't see often, just double-check on the side effects and make sure it doesn't cause a lot of hyperglycemia.
So what's next? So let's go back to George. So for him, it's safe to do an outpatient workup. And the reason is his blood sugar is high, it's 572. But most likely he has Type 2 diabetes and he still has some insulin reserves. He is completely asymptomatic. This is actually one of the most spry 63-year-old patients I've ever met, especially with all the co-morbidities that he has. Super energetic, feels great, walked in saying he feels great.
So the other labs, I'm going to pause on that for a second, but that's your third safety measure of let's look at the other labs and see what they're doing. And then number four, safety measure, health literacy. He is health literate. He has his medications at home. He has a glucometer. He knows what to do. He is just choosing not to do it.
And then underlying cause. So he's not taking his diabetes medications right now. So most likely, that is the reason for the high blood sugar. It really fits the picture. It makes sense. Keeping in the back of your mind, if they have any other weird symptoms, like does he have send infection, does he have chest pain or anything like that, to investigate does he have those risk factors for high blood sugar.
So let's do the workup algorithm. So I'm just going to recap this one more time. So how high is it? Do they have symptoms? Yes? Go to the year. What do the other labs show do? Are they super crazy? Do they have renal impairment? Do they have all this other stuff that you're like, "Oh my gosh, I do not feel comfortable with this"? Send them to the ER, that's totally fine.
Step number four, patient health literacy. Are they competent? Are they not competent to take care of themselves at home? Or do they need the assistance of somebody in the ER, even if they could manage it outpatient? Step number five, identifying the underlying causes, and then treat the underlying problem, which is diabetes. Or that underlying illness that they have, which they might need to go to the ER for, for their lab work for.
And then also, you're going to do a lot of hydration for these patients. And that's really case by case dependent being really careful with the co-morbidities of cirrhosis or CHF or fluid overloaded patients, being really careful about that. Also, that would play into the safety aspect. Do you feel like you can treat them outpatient? Probably not. But the patients who don't have those fluid overloaded statuses, giving them hydration and advising them to take NPO fluid.
So I'm going to come back to management for George. So this slide is talking about his lab results again. So glucose of 572. BUN and creatinine, GFR, sodium, potassium, chloride, carbon dioxide. So number one, patients who have HHS or DKA can be up to six to eight liters negative in terms of total intake and output. So we want to talk about hydration, adequate hydration for this patient.
Number two, we're going to add some insulin for him. So he's not taking his medications very consistently. So what we talked about is consistently taking the BID NPH, and then also checking his blood sugars consistently and doing the sliding scale as he was advised before, which he actually had under control over a year ago.
So number three, I'm going to review the alarm signs for him. So what are the signs and symptoms that he's not getting better? One, checking his blood sugar and it's not going down. It's going up again. Does he have any of those neurological signs, like the confusion or lethargy or mental status changes, he just doesn't feel like himself? He should definitely go to the ER.
Again, checking his blood sugars at home. So when I first started as a new nurse practitioner, I should make a note here that I did this in conjunction with an internal medicine physician, because this was a pretty complicated case that I feel comfortable with now, but at the time, I did not feel comfortable at all. But I actually called him and I was like, "You need to check your blood sugars every two hour," because they used to work in the hospital and that's what we would do.
Another note here in terms of checking blood sugars, so when I got this lab result, I did not check his finger stick at the time. I just had him do labs that day because I knew he needed an A1C, and he was feeling totally fine. So I got this blood test several hours later, and so it's the evening at this point. And so his blood sugar was 572, but it definitely could be down to 200, or it could be even higher than that. So that's something to think about. Can he check his blood sugar at home and make sure that it's going in a right direction?
And then for him, I also rechecked his labs in a few days just to make sure that his other abnormalities were back to normal. And so I'm going to touch back on this because if you haven't seen the hyperkalemia episode yet, you can pause here and go back to that or I can loop you in here. Hold on, I think I have another slide actually. One second. I don't. So I don't know what happened to my slide. So sorry about that.
So his sodium is 126. The corrected sodium level for this patient, so 126, if you remember from the hyponatremia presentation, 130 is your magic number. So this patient has 126, which is less than 130, which is really disturbing. But remember, your first step for low-sodium is to look at the glucose and do that sodium correction score so that you can bring your sodium back up to the right level. And again, if this is not making sense, definitely watch that video. It's a really, really great one and very clear about how to work up low-sodium, which can be a really tricky one. But that's going to correct your score so that it's actually closer to 134. So it's still a little bit low on the sodium, but it's not 126, which is much more dangerous.
And then again, potassium hyperkalemia. So it makes sense that his potassium is this high because his glucose is this high. And once we bring the glucose down, all of that potassium is going to go into the cells with him and bring it right back down to normal. So that's it for him.
So George, so I'm just going to recap his care here. So we restarted the sliding scale, taking NPH consistently and checking his blood sugars again. We rechecked his labs in a few days. I think it was two or three. There's no real set like, "Oh, you have to do it in a week or whatever." But we expect all of his labs to start returning back to normal in the next 24 hours or so. And so if he's asymptomatic, you can do as soon as the next day, or the day after if you're feeling really nervous. That's totally fine.
And then again, we're going to continue the levothyroxine because TSH was normal. I'm going to lower his blood pressure for renal protection. At this visit I avoided ACEs and ARBs at that time because of his high potassium, and I didn't want to raise the potassium even higher, which is a side effect of those two classes of medications. And I also did a nephrology referral because I wasn't really sure about his kidney function.
And actually, going back for a second, we're going to go back to the lab. So one of the things I wanted to say here is that keeping in mind if you're going through those safety steps of number one, how high is it? Number two, do they have symptoms? Number three, looking at their other labs. He could possibly have a creatinine this high related to an acute kidney injury, because his last renal studies that were done a year prior were actually in the normal range.
And so I did this in conjunction with an internal medicine physician who felt really comfortable at the time with this management. But if this was me on my own, or if I was a brand new grad again, I probably would have sent this guy to the ER. And I'm trying to remember off the top of my head, maybe if he refused me to go to the ER, maybe that's why we managed him outpatient. I can't really remember. But this is kind of a really intense case. So if you see this patient in your practice, absolutely you can send this patient to the ER. I think now that I'm remembering it, I'm pretty sure we did a harm reduction strategy of managing him outpatient with very strict recommendations about those alarm signs and when to go to the ER, and documenting very well, like he's refusing to go the ER.
So I sent them to him for a nephrology referral because most likely... And his creatinine did stay the same when I did the recheck, even though the glucose came back down and the potassium also normalized and the sodium normalize. But the nephrology referral, I did that because I wanted to do a workup and make sure that there's no other reasons for the low renal function, and whether or not it's related to the diabetes or the high blood pressure, if there's something else going on. Because there are other labs that they can do that I'm not going to do as a primary care.
And then I told him to follow up with me in about a month, and then every month to three months after that, just to check in and do that coaching and encouragement of like, "Let's get your diabetes under control," even if I'm not necessarily checking an A1C every month.
So that's it. I'd love to hear from you. What is your number one insight you've taken away from this video about high blood sugar that you can apply to your current practice? And if you have any other questions about diabetes, you want to hear more about the management and that kind of side of things, this is really focusing on the workup aspect, definitely leave me a comment below. Because I make these videos for you, and so I want them to be really helpful. And so definitely leave me a comment below with any of that information. Or find me on Facebook or Instagram.
So did you like this video? If so, hit like and subscribe and share with your NP friends, so together we can reach as many new grads as possible to help them take their first year a little bit easier too. Hopefully these are making your first year easier. And don't forget to head on over to realworldnp.com and sign up for the email list. You'll get these videos straight to your inbox every Tuesday with some little notes from me, patient stories, more practice insights and tips, and things I just don't share anywhere else. Thank you so much for watching. Hang in there and I'll see you soon.
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