It’s just after 05:00 am.The tones come across the radio. It takes me a second to figure out where I am and what is going on? Is it my alarm clock? Am I at home? Then the voice from dispatch comes across the airwaves, I know it is not my alarm and I am not at home. I wish I had turned the volume down. I’m struggling. I’m tired. I’m sluggish and moving slowly.
Some early morning calls I can sleepwalk through, accomplishing everything that needs to be done without ever becoming completely awake. I can dole out fentanyl to a broken hip and remain groggy; not asleep, but not fully awake either, easily going back to bed after the call. An early morning lift assists requires being just a little awake, but I can stay mostly asleep. This is not going to be one of those calls. I am going to need to fully wake up for this call. We are going to be here for a while.
Pulling into the driveway my cognitve functions struggle to overcome sleep inertia. I communicate in mostly grunts. If the response time were just a few minutes longer I’d have finished an energy drink on the way to this call. My prayers to the gods of caffeine fall on deaf ears—half an energy drink will have to be enough.
The BLS fire department beats us to the scene by three minutes, obtaining an obligatory set of vital signs and basic history. They hand me a piece of paper with the name, medical history and medications.
The patient is an older male. He is pale, cool and diaphoretic. His blood pressure is awful at 60/20mmhg. Despite the profound hypotension he’s surprisingly alert and oriented and can answer all our questions. He doesn’t feel like talking much though. I can’t blame him, don’t think I would either with that MAP.
The wife serves as the main historian, telling us that patient woke up too weak to get out of bed about an hour ago. She checked his blood pressure. After getting 60’s over 30’s she called 911.
In profoundly hypotensive patients, you need to figure out where the blood went. The answer is almost always one of the following: they lost it through bleeding, the pipes became too big for the volume of blood they have, the blood is there but the pump is not working, the fluid components of the plasma have been depleted through dehydration, or leaking out of the vessels. Sometimes it is a combination of these things. It matters because in some cases the patient will receive fluids and Levophed right from the start and in other cases they might just get fluids, or they might just get medications.
Aside from the blood pressure, all other vital signs are normal. The heart rate is in the upper 60’s—not low enough to cause any problems, but lower than expected with this blood pressure. A double check of the medication list does not show any beta blockers. The respiratory rate is normal at 20 per minute and the spo2 is 100% on room air. Keep in mind that this is in the mountains of Colorado at 7,000 feet. Most people have an SpO2 of 95-96% here on room air. It is odd that the SPo2% is so high, but then again, so what?
A 12 lead ECG does not offer any help, showing a sinus rhythm with no abnormalities. His lungs are clear to auscultation. His etco2 is lower than expected at 20cm h20 with a “square” waveform. There is no fever present and no signs of GI bleeding are reported. There has been no diarrhea or vomiting and he has been eating and drinking normally, having had dinner last night.
In the kitchen, the wife gives me more of a history. After the initial diagnosis of cancer, about 18 months ago, the patient had a Whipple procedure. He was doing better for a year or so. A recent MRI found some concerning spots in his bones and other organs. The patient has been feeling a little tired and off for the past several days.
left with hypotension and hypocapnia of unknow etiology, sepsis crosses my mind, but where is the source of infection? Some sort of runaway inflammatory process could be to blame, but that should come with a higher heart rate. I am unsure if SIRS is still a thing anymore—I think it is. I make a mental note to look it up. I never do. Something crazy like a tumor lysis syndrome might be the culprit, but that seems less likely. Something about that Whipple procedure is familiar. Wishing I got to drink the entire Bang on the way, not just half of it, trying to force myself to remember, it comes to me slowly, painfully.
I think the Whipple procedure is where they take out most of (all of?) a couple organs in your abdomen. Pancreas, gall bladder and maybe part of something else? They do something with the stomach and intestines and, well, I don’t know for sure, but I know they take a lot of things out. Mostly though I just think of the commercials with Mr Whipple. What the hell was that all about? For those of you who are younger than thirty you will be lost here. Decades ago, Charmin toilet paper had an ad campaign where customers would obsessively try to “squeeze the Charmin” in stores while the lone defender of the toilet paper was Mr Whipple—a bespectacled clerk who’s main job description was to prowl the toilet paper aisle and prevent people from squeezing the Charmin. It is unknown what sequelae occurred from Charmin that has been squeezed—was it obsessive compulsion on the part of Mr Whipple? Perhaps the unspeakable ancient Lovecraftian horrors would return to Earth if a certain threshold of Charmin were squeezed?
“That’s where they take out part of your pancreas and gallbladder, right?” I ask the wife. She says yes. Is it part of the pancreas or all of it? How much pancreas can you take out and still have enough beta cells? It is beta cells, right? I force myself to focus again.
“Does his pancreas work? what is left of it?” I ask.
The wife tells says that they removed the entire pancreas. She is apologetic, admitting she forgot to mention that they also give him insulin every day.
“Check a sugar, please,” I yell from the kitchen to the fire department. The fire department says the sugar is 44mg/dl. Asking the wife if they check the patient’s sugar regularly, she says yes. She says the sugar has been running over 200 for the past week and there have been no changes in his insulin.
Thinking we can avoid carrying the patient down two flights of steps if we fix the sugar now, I say, “get out the D10.” I tell the patient that I think he’s going to feel better after we fix his blood sugar. But hearing myself say it out loud instills some doubt in me. something about this doesn’t sit well with me. He seems too alert for someone with this blood sugar, and why would he be so hypotensive? How the hell does he have that spo2? Mine is never, ever that good and I am in decent shape an run 95% but this shocky, cancer patient has an spo2 of 100% at 7,000 feet on room air. Hypoglycemia explains pale, cool, diaphoretic skin but it doesn’t explain everything that is happening here. These folks seem like they manage the patients care very well—they do not seem like the type to give an extra dose of insulin or give insulin after skipping dinner. Unless this patient suddenly developed an insulinoma, I cannot explain the hypoglycemia.
“Hold off for a second on the D10,” I say.
My vague sense of unease is solidifying. I do not think this is hypoglycemia at all. Just the opposite in fact.
“Can you recheck that sugar with our glucometer please?” The first one, the 44mg/dl one, was checked with the fire department’s glucometer. Using the EMS glucometer, the blood sugar returns at 494 mg/dl. A confirmatory repeat comes back at 504 mg/dl. This fits the clinical picture better and silences my internal alarms. I believe this to be hyperglyecmia and dehydration secondary to osmotic losses.
The D10 is put away. A bolus of Lactated Ringer’s is infused, and the blood pressure comes back up. The etco2 of 20 and the spo2 should have been a clue that the patient was hyperventilating. While his rate was normal his tidal volume was exceptionally large.
Rechecking a blood glucose is not something that is routinely done; and I’m not advocating that it should be. I suspect the fire department did not push the lancet down hard enough and had to squeeze the finger hard, getting a sample that was mostly fluid from the tissue instead of actual blood.The patient was found to be in DKA at the hospital and had anemia of an unknown etiology and was admitted to the ICU.
It might be easier to start with what intuition is not. Intuition is not a type of mystical wisdom, it’s not divine knowledge imparted from the spirit world, and it isn’t getting in touch with frequencies, psychic powers, sacred energies, or any other forms of crystal-gripping woo. Intuition is not about using clairvoyance or being an empath or any other new-age magical thinking. All that stuff is bullshit.
“intuition is nothing more and nothing less than recognition,” says Daniel Kahneman, author of Thinking Fast and Slow Clinical intuition is likely the subconscious recognition of patterns and small signals. It may come across as a gut feeling or a nagging thought that something just does not seem right or does not fit.
In the paper Experienced physician descriptions of intuition in clinical reasoning: a typology the authors collected stories from thirty experienced physicians about utilizing intuition. With theses collected stories they formulated a typology of intuition.
The four types of clinical intuition
- Sick/not sick/not sick yet, but heading there
- Something is not right
- Frame shifting
- Abductive reasoning – a logical leap
4a. Eureka moments - Dr House.
- Sick/not sick. Walking into a room without gathering any vital signs, ECG, or even a history, the fact that the patient is sick is instantly recognizable.
- The mismatch: All the vital signs are normal, but the patient just seems sick to you, or vice versa and the patient might appear unwell, but something does not fit.
- Something is not right. I once tried to refuse a patient who had a 5mph bike accident. They could not tell me why they wanted to go to the hospital, just that they did. They had no specific complaints; no injuries and their vital signs were totally normal. But they seemed oddly anxious. An hour later when they became diaphoretic in the ED, an abdominal CT revealed that they had destroyed their spleen.
- Frame shifting: When a pattern is recognized, and the entire diagnosis may change. It may be a solitary clue trigger a reevaluation of the current diagnosis. In the above case it was the mention of a Whipple Procedure. More recently, a patient that called for a lift assist causally mentioned that they had a pessary placed last week. Asking more about that revealed they were unable to void and must self cath 5x a day and had a UTI for the past two months. The fall was likely generated by weakness secondary to a UTI. Shifting the frame from a lift assist and no aid needed to a “you should go get checked out at the hospital,” rested on picking upon the one subtle clue.
- Abductive reasoning: Abduction is used to generate possible explanations/hypotheses for incomplete observations, surprising facts or puzzles early in the diagnostic process. Deductive reasoning deals with certainty. Inductive reasoning deals with probability based on data. Abductive reasoning entails a best guess approach based on a limited set of information. This is the hallway diagnosis. This is staring at the ashen and sweaty 56-year-old male and within seconds formulating that hypothesis that he is having “the big one,” or conversely hearing about someone with chest pain and upon looking at them believing this is not an AMI.
- Eureka. This is pretty much every episode of House ever made.
Who Should Rely on Intuition?
Aside from psychic surgeons, no healthcare provider should rely entirely on intuition for a diagnosis. Intuition should be used in parallel with analytical thinking, logic, algorithms and the occasional heuristic.
Daniel Kahneman’s Three Requirements to Trust Intuition.
Daniel Kahneman, author of Thinking Fast and Slow, proposes that three things must be in place before we should trust intuition in situations like clinical judgment.
1. The situation must be predictable and regular. Intuition in gambling where it is a up to chance is not valid. Gut feelings about “scratchers” at the gas station are almost always a losing proposition.
2. Lots of practice. Enough to verge on the domain of expertise. You must notice patterns and file them away in your brain for later use. This allows you to say that something either fits a specific pattern, or that is does not fit the specific pattern you thought it did and change paths. Kahneman says when expertise is present, we should heed intuition, when expertise is not present it should be ignored.
3. Timely feedback. This allows you to calibrate your intuition. You need to see if your intuition was right or wrong. Without seeing if intuition is right or wrong there is no way to calibrate it.
Trust But Verify.
Should new EMTs or paramedics rely on intuition? No. To the new EMS provider, every drunk patient is really a hypoglycemic diabetic with a head bleed that needs spinal immobilization, every vague symptom occurring above the pelvis in an elderly female patient is an atypical MI, and all back pain is a dissecting abdominal aortic aneurysm. To the new graduate, every call is the worst-case scenario, every time.
Worst-case scenarios must be considered in formulating differential diagnosis, otherwise things will get missed and patients will suffer, but catastrophism needs to be balanced with objectivity and an understanding of prevalence. Hypothesis must be quickly deemed as more likely or less likely than another hypothesis as new information emerges. The ability to disengage from diagnostic momentum is often a challenge.
This is not a slight against the new graduate—paramedic schools don’t explore Bayesian updating. SAMPLE is a rote line of questioning, one without tangents or reflection on what the answers mean. Probabilistic thinking is never employed, and prevalence is never mentioned. Teaching how to diagnose patients is hard—a majority of our peers feel that diagnosing is something we are not even allowed to do in EMS—prohibited by some shadow agency such as the HIPAA police or EMTALA squad or worse, subject to the whims of “The Lawyers.” Doing mental gymnastic and arguing semantics to avoid even saying the word diagnosis—choosing to use terms field impression, field diagnosis, just treating symptoms, and other such non-sensical terms is irrational.
In the experienced provider, using intuition is a valuable skill. It requires being able to hold multiple opposing thoughts at once, asking “what if I am wrong here,” and frequently engaging in self-reflection and high levels of accountability. It requires high levels of meta-cognition and examination of one’s own biases and (mostly flawed, in my case) thought processes. Intuition is mostly a lesson in cognitive biases, and frequently one in being wrong. But every so often intuition is a signal that should be given extreme importance.
This is not to encourage skipping steps or risk taking. Gather information to confirm, or more importantly to employ falsification to disconfirm your hypothesis. In the experienced provider multiple modalities of diagnosis must be used; induction, deduction, abduction, intuition, heuristics, Bayesian analysis and more need to be considered.Trust your gut but prepare to be wrong. Use both sides of your brain and your gut when diagnosing.