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In a fog

Last updated: March 31, 2025

Case instructionstoggle arrow icon

Concerned about managing a patient's acute mental changes at 4 am when you're experiencing your own sleep-deprivation delirium? Take 10 minutes to work through this module and leverage your AMBOSS resources as a backup for your tired brain!

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Pager alert!toggle arrow icon

You're the night-call intern cross-covering the general surgery service. It's the wee hours of the morning, and in the eerie silence, the empty halls of the hospital feel so much like a ghost town that you wouldn't be surprised if a tumbleweed blew by. You settle into the resident work room and turn on the TV for some company. An old black-and-white Western comes on. Not usually your thing, but it kind of fits the vibe right now. A dramatic duel is just beginning...when your pager goes off.

Click the pager icon to reveal the message.

Well, who isn't confused and difficult to arouse at 4 am? You'd be difficult to arouse too, if you were in your nice warm bed right now...with those soft flannel sheets… But since you're the intern on call, you must make a decision.

Question: How urgently should you assess the patient?

Make your choice, then click on the explanation bubble to reveal the answer.

  • Right now
  • In the next hour or so, once the morning labs come back. Then you'll have a more complete picture.
  • Eh! The patient's probably just trying to sleep. It is 4 am, after all!

Only a rookie attempts to assess the severity of a condition or estimate its progression without seeing the patient!

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In the elevatortoggle arrow icon

You’re on your way to see the patient. While taking the elevator up to the patient’s floor, you have a minute to calmly assess what you already know and build a differential diagnosis.

Signout sheet review

Pull out your signout sheet to review critical information about the patient quickly. Here's the information you have for this patient.

Question: What is your broad differential diagnosis for confusion?

Think of an example for each of the following, then click on the explanation bubbles to reveal more information.

  • Primary CNS dysfunction
  • Hypoxia and/or hypoperfusion
  • Infection
  • Endocrine and/or metabolic
  • Medications
  • Withdrawal
  • Psychiatric
  • Environmental

Many patients with altered mental status have their entire story tucked into the “Medication Reconciliation” tab of their chart. Don’t skip it!

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At the nurse's stationtoggle arrow icon

The elevator opens on floor 5. It's amazing how quickly your adrenal glands rallied and gave you a fresh rush of epinephrine! Though you may feel like sprinting alone to the patient's room, you don't have to be a hero right now. Instead, you look for the patient's nurse.

Question: When you find the patient's nurse, what do you do?

Make your choice, then click on the explanation bubble to reveal the answer.

  • Thank the nurse for paging you and calmly ask for an update.
  • Demand immediate answers and show your displeasure if the nurse has to riffle through their papers for the patient's information.

Kindness in chaos isn't a luxury, it's an asset!

More information, please...

Here are some questions you can ask the nurse while you're en route to see the patient together.

  • Onset and duration of confusion
  • Patient's baseline cognitive function
  • Vital signs and trends over the last shift
  • Additional symptoms (e.g., pain, fever, cough, falls)
  • Recent medication administration
  • Notable recent events or triggers (e.g., complicated surgical course)
  • What does the nurse think is going on?

The nurse may have decades of experience that you do not have. Make them your ally. Even the Lone Ranger had a sidekick.

You may also need to pull up the electronic health record (EHR) to get additional information on trends and things that have happened before the current shift.

Avoid deep dives into the EHR until after you have seen the patient.

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At the patient's doortoggle arrow icon

You and the nurse arrive together at the patient's room.

Question: Which of the following can you immediately assess from the doorway?

Make your choices, then click on the explanation bubbles for more information.

That's right—all of the above!

You can usually tell if the patient is very sick while you're still in the saddle.

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Pick your own adventuretoggle arrow icon

You've reached a fork in the road.

Question: Which clinical scenario would you like to explore?

Choose an option to continue the module.

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Wrap-uptoggle arrow icon

Congratulations! It may have been your first rodeo, but you saved the patient!

  • You succeeded in:
    • Recognizing the need to quickly triage a potentially critically ill patient
    • Knowing where to quickly find the critical information needed to help your patient
    • Coming up with a broad differential diagnosis for confusion
    • Calling for help promptly
    • Identifying opioid overdose (Option 1)
    • Balancing urgent treatment of an acute problem with comprehensive assessment, including thinking of all the critical causes of AMS (Option 2)

Congratulations on completing this module. Hopefully you now feel more comfortable assessing a patient with confusion!

Personal story from an AMBOSS clinician

I was the receiving physician at a military hospital adjacent to an active combat zone. A 20-year-old soldier was transported urgently to our hospital from a smaller medical unit after he developed acute, progressive confusion following surgical treatment for a traumatic lower leg injury. In the postanesthesia area, he was noted to have an SBP of 85 mm Hg and minimal urine output. He received 3 liters of IV fluids over the next 30 minutes, which corrected his hypotension. A bedside hematocrit was 30% after the fluid resuscitation.

The soldier started becoming confused about one hour after the surgery was complete. The referring physician was worried about an unrecognized traumatic brain injury or a fat embolism. He was transferring the patient to our hospital for an emergency head CT. Vital signs were heart rate 110 beats/minute, BP 160/95 mm Hg.

On the helipad, the patient was somnolent but arousable. He was breathing spontaneously with a respiratory rate of 20 breaths/minute. His oxygen saturation was 100% while receiving oxygen at 6 liters/minute by face mask. He was moving all four extremities spontaneously with obvious tonic-clonic movements. We were readying him for immediate movement to the CT scanner when the corpsman said, “Doc, look at this.” He was holding up two empty IV bags labeled D5W. The patient had been given the wrong fluids. We drew blood for a stat BMP and CBC as we ran to the scanner, started an infusion of normal saline, and called for the pharmacist to bring us hypertonic saline.

By the time the patient was out of the scanner, we had the CT results (diffuse cerebral edema) and the lab results (Na+ 104 mEq/L), and we were starting the first bolus of 100 mL of 3% NaCl (along with other elements for the management of elevated ICP).

The lesson I learned: Keep your differential for altered mental status broad. Never forget the possibility of electrolyte abnormalities and/or iatrogenic injury.

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