A nice week of spring fling came and went. in honor of the return of the cold. lets have a discu-shin about an uncommon, but deadly cause of hypothyroidism - myxedema coma.
Why do I care?
because mortality rates in treated MC approach 60%
if missed and untreated, mortality approaches 100%.
How does it present?
Severe hypothyroidism --> everything slows down. hypothermia and decreased mental status are hallmarks, other common signs are hypotension, bradycardia, hyponatremia, hypoventilation, and hypoglycemia.
interestingly, it is aka myxedema madness - as sometimes patients present with psychosis.
due to its rarity it can be a confusing Ddx - think of a patient with multiple failing organs whose lethargic, hypotensive, and hypothermic
ddx include sepsis, CHF, tox, adrenal crisis
to make things more complicated, myxedema coma usually occurs in a patient with hypothyroidism as a result of a precipitant
any systemic insult can push a patient in to myxedema (overdose, CHF, CVA, sepsis, trauma, etc.)
so youre saying the differential diagnosis can actually be the cause?
YES I AM
So how will i recognize it????
You'll send a thyroid panel to the lab
and you'll realize that your standard treatments for whatever else may be present just are not working as well as you'd expect them to.
BP will not respond to pressors as well you'd expect.
How do I treat it?
controversial. most agree to adminster both T3 and T4 (levothyroxine)
T4: 4mcg/kg IV
followed by 75-100 mcg daily IV until patient tolerates PO
T3: 10mcg IV
followed by 2.5-10 mcg IV daily
concomitant adrenal insufficicnecy may be present
administer hydrocortisone 100 IV q8
where should i send this patient?
to the MICU. and get your endocrinologists involved.