Altered Mental Status – So what was it?

I hear a few different things thrown around over on the AMS case study, head bleed among them. I was leaning that way as well, but I’m still waiting on the feedback. The squeaky wheels of progress turn slowly, I’m still waiting to hear back about 2 cases with unusual ECG’s and ACS symptoms but didn’t go to the cath lab right away. Hopefully the hospitals involved will get with the program.

So you may or may not know, altered mental status emergencies can be caused by many things: stroke/CVA, hypoglycemia, thyroid problems, etc. The most common of these encountered are diabetic emergencies.

Since we know plenty about diabetic emergencies, but thyroid related emergencies are something we don’t encounter all that often or if we do we don’t know it. Really, the only way you will discover this as a problem is by a past medical history review and by looking at the patient’s medications. This week we will cover hypothyroidism.

Hypothyroidism is an endocrine disorder where the thyroid gland produces less hormone causing a slowing of the metabolic process. The process itself is slow but when the replacement of hormones, usually a pill or shot, it can become an emergency when the body suddenly runs deficient of thyroid hormones.

The thyroid gland secretes hormones in response to thyroid stimulating hormones (TSH) from the anterior pituitary gland. This is triggered by a release of thyrotropin releasing hormone (TRH) from the hypothalamus. Approximately 95% of all hypothyroidism cases that are diagnosed by physicians is called primary hypothyroidism, where the thyroid gland fails directly. Other causes include radiation ablasion and congential problems.

Patients with undiagnosed hypothyroidism or insufficient replacement therapy may complain of a variety of symptoms, which if you suspect a thyroid problem, you should ask the patient about some of these:

  • Lethargy
  • Generalized weakness
  • Menstrual irregularity
  • Menorrhagia
  • Forgetfulness
  • Fullness in throat
  • Deep, husky voice
  • Cold intolerance
  • Weight gain
  • Muscle/joint pain or weakness
  • Inability to concentrate
  • Headaches
  • Constipation
  • Emotional lability
  • Depression
  • Blurred vision

In an emergency, you may be called for any of these symptoms. How many patients have you seen complain of these symptoms which prompted a call to 911? They easily mimic several different conditions which may or may not initially appear to be an emergency. When doing testing and exams, you should look for:

  • Pseudomyotonic reflexes – Prolonged relaxation phase, usually at least twice as long as the contraction phase
  • Hypothermia (especially in myxedema coma)
  • Skin changes – Dry, cool, coarse, and thickened with a yellowish appearance
  • Subcutaneous tissues – Nonpitting, waxy, dry edema
  • Pallor
  • Loss of outer one third of eyebrows
  • Abdominal distention
  • Goiter
  • Unsteady gait/ataxia
  • Dull facial expression
  • Coarsening or huskiness of voice
  • Periorbital edema
  • Bradycardia, narrow pulse pressure
  • Thyroidectomy scar – In patients with altered mental status, suggests myxedema coma as a potential cause

So now that we know what to look for, there are other conditions that share these symptoms that you should be aware of, as the treatment modality may change slightly. CHF and pulmonary edema will cause the edema and associated respiratory problems. We can manage pulmonary edema with nitrates and CPAP. Sepsis can mimic other symptoms and we can effectively manage the associated hypotension with fluid and vasopressors like dopamine. Monitoring circulatory and ventilatory status is important.

Patients that have hypothyroidism will be on hormone therapy medications, and you should pay attention to the medication list. The most common medication is Levothyroxin, otherwise known as Synthroid, Levothroid, or Levoxyl. If you notice a medication like this in the list, your suspicion of a thyroid emergency should be heightened.

So, only we’ve identified that a thyroid disorder is likely, how can we fix it? The long and short answer: We can’t. Management of symptoms is the farthest we can go, and from what I’ve been reading, patients with hypothyroid emergencies will present in extremis and will require aggressive management to stabilize.

Remember that your next altered mental status patient may be having a thyroid emergency, so you should take a careful history and a through exam and be prepared to treat aggressively.

Sources

http://emedicine.medscape.com/article/768053-overview

http://www.emsworld.com/publication/article.jsp?pubId=1&id=6383