Cognitive error in trauma: “My wife won’t get out of bed”

0

Imagine your emergency department receives an elderly patient who has been bedridden for a week with reduced water and food intake. There are none of the obvious cues to trauma. No fall at home or at a store. No trip in with EMS. No lights and sirens. Your immediate working diagnosis would be something like urinary infection, pneumonia, a missed stroke or heart attack. And you would be wrong.

Patrick J. Crocker, DO, MS, FACEP

I know, because I received this very patient a few years ago at the ER where I worked. All the signs pointed to a medical complaint. But in fact, the patient’s presentation set the stage for a cognitive error leading to missed trauma.

I wrote about this patient in my recent book Letters from the Pit: Stories of a Physician’s Odyssey in Emergency Medicine, and the full details are in the excerpt below. As you read through the case, I suggest you watch for two specific cognitive errors:

  • Availability bias. Everyone is vulnerable to this thinking error. When solving problems, we tend to favor readily available information. It’s when your brain tells you, “The last 50 patients with this presentation had one of these four issues, you see these four issues in the elderly all the time,” and so on. Availability bias pushes you unknowingly into error.
  • Premature diagnostic closure. Physicians need to make a diagnosis, even when the facts don’t completely add up. In the case of the patient described below, I was very close to admitting her for dehydration and early sepsis — an incorrect diagnosis that could have led to a very different outcome.

As a bonus, you might also want to think about the problem of diagnostic momentum. This occurs when the first doc comes to an erroneous conclusion in his or her diagnosis and this bias is then carried over to the next providers, inducing them to accept the same error.

I know from experience that once these three errors are working against you and the patient is on the floor, it takes a conscious effort to discard all that you believed about the patient, start over and come to the correct conclusion. Fortunately for this patient, that’s exactly what happened.

Excerpt from Letters from the Pit

I learn something new every single day in the ER. That is a big part of what has kept me fascinated with this practice over the years. Today, it was a reminder about the power of observation, about really looking at what is going on and trying to understand its relationship to the patient.

My patient was in room thirteen. Though I am not superstitious, I am reminded that many people are wary of this number. The chief complaint, written on the top of the chart, reveals little. It merely says my next patient won’t get out of bed. I silently wonder what I will find.

As I enter the room, my patient, a seventy-five-year-old woman, is lying flat on her back, eyes open, and in no obvious distress. Her husband is sitting disinterestedly near the foot of the bed, reading a magazine. This strikes me as a bit odd, but perhaps he is just expecting a long wait and is getting comfortable. I introduce myself and shake his hand, as is my practice, and turn to the patient.

She looks like she is chronically ill, not emaciated, but rather thin. Her eyes are open, but she stares only at the ceiling and offers little response to my questions. This sort of presentation in the elderly is not uncommon. Some patients refuse to go the doctor until they are critical, while others come to the ER with a simple scratchy throat at 2 a.m. on a Saturday night. I wonder how long she has been like this and begin to question her husband, even before I have started my exam.

He says his wife has been ill for about a week. She has been refusing to get out of bed, even to eat. She has been taking fluids, however, so, he has made her chicken broth daily. The recalcitrance to call for a physician’s help surprises me, but again, is sometimes common in the elderly. That’s odd because they are precisely the group that should have a lower threshold for seeking health care. They’re the ones at highest risk for real disease.

I learn my patient has had no fevers, chills, or falls. The rest of her medical history is really of little help. She is on the usual cocktail of medications, and right away I wonder if they are the cause. I have always been bothered by how often our medications contribute to problems instead of healing us. Before reaching for the prescription pad, we would do well to consider primum non nocere.

I start my exam and go from head to toe carefully. Her mental status is clearly abnormal. Her lips are cracked, and the back of her throat is dry, so, I naturally suspect she has some dehydration. There are no marks of prior trauma. Her breathing is a bit labored, and there are little crackles in her lungs that suggest maybe pneumonia.

As I begin to examine her abdomen and pull down the bed sheet I find she has soiled herself with feces. I pull the sheet back up quickly and simply feel her abdomen. I find it soft and benign. Her extremities are all symmetrically weak. I am unsure of the cause at this time. The only other notable issue is her blood oxygen is a little low, showing ninety percent saturation on the monitor. I order a little nasal oxygen. I tell the husband I will be ordering lab and X-rays. He simply says, “Good.”

As I walk back to the computer to enter orders, I call out to the nurse for a STAT blood sugar test. Blood glucose is one of the first things to treat if it is low and could be the cause of everything. I am also considering the differential diagnosis. This is what we call the list of possible problems that could explain this presentation. And in this case, it’s long. I order routine labs, a sepsis screen, a catheterized urine sample, a CT scan of her brain and a portable chest X-ray. A few other tests as well. An infection or a stroke is high on my list right now. Both problems are all too common in this age group. I also ask the nurses to clean up the patient after giving them the bad news that she has soiled herself.

Her sugar level turns out to be a little low, fifty-eight instead of at least seventy. That’s not enough to explain all of this, but I treat it anyway. She hasn’t eaten solid food in a week, so I figure a little IV glucose won’t hurt her. And then she is off to the radiology department.

An hour or so later, the studies I ordered return. A CT scan of the brain fails to show a stroke, hemorrhage, or fracture. I look it over myself. Once in a while, even the radiologist will miss something, and I have looked at thousands of scans. Similarly, I study the chest X-ray. There is no pneumonia. I am beginning to gravitate toward the possibility of a urinary tract infection as a cause. But the urinalysis returns pretty normal, except for high ketones from not having eaten for a week. Her other labs are pretty unremarkable, although they confirm dehydration.

So, now it’s a bona fide mystery. Why won’t she get out of her bed? Why does she lie here now, semi-conscious, almost like she’s sedated? I speak further with the husband while the staff unceremoniously, though with dignity, remove all of her gowns and underwear to clean her.

And there with the sheet off and her in her birthday suit I notice something I missed while she was gowned and under the sheet. Her breathing pattern is highly abnormal. She is using abdominal and other accessory muscles to breathe.

Now this is really odd. There are a number of causes for this, but with her presentation and with her weak extremities, I am suddenly concerned about a potential spinal cord problem. Has the blood supply to her spinal cord become impeded in some way?

We place a cervical collar on her to help protect her neck from further injury. She is awake enough, responds to pain, and likely able to do this herself, but I put it on anyway. Even with no history of trauma, this protection is important. Maybe the paramedics who brought her or I should have done this at the start. Spinal fractures can occur in this group with very little trauma. Bones in the spinal column that are riddled with osteoporosis simply collapse under the body’s weight. Just how fragile the aged become scares me a bit.

I ask the husband again about falls. He says no, no falls. But she stumbled about ten days ago. She never hit the ground and didn’t seem to hurt anything, he says. These collapses of weak vertebrae usually cause pain and disability but only rarely damage the spinal cord. It can happen, though. So I order a STAT portable cervical spine X-ray. Alarms are going off in my head as I put this all together. I have become convinced her problem is mainly neurological.

The X-ray of her neck returns in just minutes and I can’t believe what I see on the film. My patient’s odontoid process, a piece of bone that sticks up from the second cervical vertebrae that both attaches our head to the neck and allows us to rotate our head, is broken clean off. Even worse, it is displaced, putting pressure on her spinal cord. And this explains everything.

Everything except why the husband hasn’t called for assistance much sooner. He insists his wife was fine a week ago, but surely, even the most recalcitrant among us would seek help if a fully normal spouse suddenly couldn’t get out of bed. I explain what I have seen to the husband, and he remains rather nonchalant, unsurprised, and rather disinterested.

What the hell? Someone here has already called Adult Protective Services. Likely, one of the nurses. That call seems perfectly in order to me, and at this point, I would be making it myself. At any rate, protective services call, wanting to speak with me. Good. I tell them the story and they say they will come directly to the ER.

I order a CT scan of her neck. I really don’t need it at this point, but I know the accepting neurosurgeon is going to want to see it. I also order blood gases. This test will tell me if she is acidotic or if carbon dioxide has accumulated in her blood. She is likely not breathing deeply enough to expel all of the carbon dioxide her body produces. When the level gets high enough, this can cause sedation. This is becoming one bizarre ending to the complaint, “My wife won’t get out of bed.”

Her blood gas test returns, and I am embarrassed by the result. Her carbon dioxide is over ninety and should be around forty. I am shocked this wasn’t more clinically apparent, as I had studied her respiratory pattern carefully. That is how I came to suspect a spinal cord problem. But there it is, right on the little piece of paper the respiratory tech brings to us each time we order a blood gas. Damn.

I order a ventilator set up and ask the staff to prepare medications to put down a breathing tube. The ventilator will help her breathe better. An intubation on a patient with an unstable neck fracture is a dangerous procedure. If not carefully done, you can displace the fracture further, causing even more damage. If you are especially unlucky, you can even sever the spinal cord. I love this job, but you can find yourself in the most precarious of positions. To help guard against making a bad situation worse, I will use a video-assisted scope to intubate. I will have other staff stabilize her head and neck while I do it and hope I can accomplish the task without moving her at all. The intubation turned out to be a breeze. The breathing tube went right in. She didn’t move at all.

Within ten minutes of the intubation, the medication to paralyze her is wearing off. Now she is trying to pull out the breathing tube! We quickly restrain her arms to the bed and sedate her mildly. This is actually great news. Her spinal cord is working better than I thought, and most of her inability to move was sedation from that carbon dioxide build up.

The neurosurgeon accepts the transfer and we call the helicopter. In an hour or so she will be in the ICU. I am hopeful that her spine can be stabilized surgically and that she will return to her life. My part of her care is almost done.

A police detective appears to question me. He wants to know what I think about this. Did her husband break her neck? Or did he just neglect her in bed? Or was he just too unsophisticated to even realize there was such a major problem going on? I have no conclusions to offer. Any and all could have happened, I say, but I add that I do not think there is evidence he intentionally caused the injury.

As I hear the helicopter take off, I take a few minutes to again ponder how fate, or chance, plays such an unappreciated role in our lives. What if I hadn’t noticed the strange way she was breathing? What if she had not soiled herself so I could even make the observation while the nurses cleaned her up? Without those two lining up just right under the stars, she likely would have been admitted to the floor for dehydration and maybe sepsis of an undetermined cause.

What if? What if? And that is why I consider observation to be one of the most powerful tools in a doctor’s bag. And sometimes I am both thankful and fearful of fate.

This case study is an excerpt from Letters from the Pit: Stories of a Physician’s Odyssey in Emergency Medicine, by Patrick J. Crocker, DO, MS, FACEP. Dr. Crocker was formerly chief of emergency medicine at University Medical Center at Brackenridge Hospital (1986 – 2007) and at Dell Children’s Medical Center (2007 – 2013) in Austin, Texas. He is a former ATLS and Combat Casualty Care Course instructor and has served as a trauma site reviewer for the American College of Surgeons.

Leave A Reply