2: R/O Medical Causes

  • Before an action can be assumed to be purely behavioral, serious medical conditions must be ruled out.
  • Use history, physical exam to guide your work-up.
    - Go see the patient!
    - Not every patient needs a head CT
  • While work-up is pending, you can continue to address the behaviors

A behavioral disturbance can originate independently, or it can be the manifestation of a medical condition. Excessively focusing on the behavior to the exclusion of potential medical causes can result in serious patient harm if a treatable diagnosis is overlooked. On the other hand, every patient that is acting out does not need a complete medical workup including head CT, MRI, blood cultures, etc.

First, consider the history. What medical conditions is this patient most likely to have based on their past medical history? What events happened to the patient recently which may predispose to a specific condition?

Exercise 1

If you saw the following in medical history, what is your differential and what might you order? Match the following orders with history elements that might suggest them

History of cirrhosis = Differential includes hepatic encephalopathy, spontaneous bacterial peritonitis, other toxin accumulation. Consider ordering ammonia, LFTs, CBC.

Surgery 3 days ago = Differential includes infections such as UTI, pneumonia. Consider ordering a UA, chest xray.

Change in antibiotics from IV to PO = Differential includes worsening infection. Consider ordering blood cultures, CBC.

History of BPH = Differential includes urinary retention, UTI. Consider ordering bladder scans, strict Is and Os, UA.

Sepsis, recently resolved = Differential includes volume overload, secondary infection. Consider ordering BNP, chest xray.

Diarrhea = Differential includes clostridium difficile, antibiotic associated diarrhea, medication effect, bowel necrosis. Consider ordering c diff or other stool studies, abdominal xray.

Exercise 2

Basic physical exam and vital sign abnormalities can help guide the work-up. With each vital sign abnormality below, free write out what work-up you might consider:

Temp 98.5, HR 120, BP 105/60, RR 20, O2 98%

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Temp 103.2, HR 110, BP 95/75, RR 20, O2 95%

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Temp 98.5, HR 95, BP 138/90, RR 50, O2 94%

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So when would you consider a stat head CT? There is not great data on this question and most of it comes from patients in the ICU setting which likely have a higher rate of structural abnormalities. There are two conditions which absolutely require a head CT:

  1. Focal neurologic findings
  2. Trauma, per Canadian head CT guidelines
Other situations are completely based on your judgement.