0071643192.pdf

ENDOCRINE, METABOLIC, FLUID, AND

ELECTROLYTE DISORDERS

Thyroid Treatment—

ProptoticPolly(Wait) Is

Dying

Propranolol

Propylthiouracil

Wait 1 hour

Iodide

Dexamethasone

Always administer PTU at

least 1 hour before iodide to

prevent increased thyroid

hormone synthesis.

■ Glucocorticoids dexamethasone or hydrocortisone: Dexamethasone has

the additional advantage of decreasing T 4 to T 3 peripheral conversion

■ β-Blockers: Propranolol is preferred because it also decreases T 4 to T 3

conversion. Consider esmolol in patients with CHF.

■ Thyroid medications

■ Antithyroid drugs block the synthesis of thyroid hormone.

■ Propylthiouracil: Preferential 2°to conversion inhibition and rapid

onset

■ Methimazole

■ Iodide

■ Inhibits stored thyroid release

■ Treat underlying stressful event.

COMPLICATIONS

■ Near 100% mortality if left untreated

■ CNS dysfunction =confusion→obtunded→coma→death.

■ Cardiovascular =tachycardia →CHF→cardiovascular collapse.

■ Avoid ASAfor hyperthermia because ASA displaces thyroid hormone from

thyroglobulin, increasing the availability of active hormone.

An elderly patient presents with pneumonia and sepsis. After treatment

with antibiotics and fluid the patients remains hypotensive. Labs reveal a

blood glucose of 50 and a sodium of 124. What other diagnosis might this

patient have and how do you treat it?

Adrenal insufficiency. Give dexamethasone (doesn’t interfere with cortisol

level testing) +fludrocortisone or hydrocortisone.

ADRENAL INSUFFICIENCY AND CRISIS

PHYSIOLOGY

■ Adrenals produce

■ Glucocorticoids: Cortisol is the major glucocorticoid. Hypothalamus

secretes corticotropin releasing factor →pituitary secretes ACTH →

adrenal cortex secretes cortisol.

■ Mineralocoricoids: Aldosterone is the major mineralocorticoid and is

controlled by the renin-angiotensin system and K+concentrations.

■ Catecholamines: Epinephrine and norepinephrine

■ Androgens: In small amounts

■ Insufficient glucocorticoid and mineralocorticoid for physiologic demands

leads to adrenal insufficiency; can be caused by 1°or 2°insufficiency.

■ 1 °adrenal insufficiency known as Addison disease and is 2°to destruc-

tion of the adrenal cortex.

■ Idiopathic: Associated with DM, Hashimoto disease, and Graves disease

■ Infectious/infiltrative: TB, fungal, AIDS, sarcoid, CA

■ Drugs: Methadone, rifampin, and ketoconazole

■ Adrenal apoplexy (bilateral adrenal hemorrhage)

■ Anticoagulation

■ Neonatal sepsis causing:

■ Infarction known as Waterhouse-Friderichsen syndrome

■ Hemorrhage