Chronic conditions:
■ CHF
■ Diabetes mellitus
■ Liver disease
■ Pulmonary disease
DIFFERENTIAL
■ Other causes of high anion gap acidosis must be considered. See “Acid-Base
Disorders” for more information.
DIAGNOSIS ANDCAUSES
■ History should lead to one of the four categories of lactic acidosis.
■ Type A: Inadequate tissue perfusion →hypoxia.
■ Type B1: Disorders
■ Diabetes
■ Renal or hepatic failure
■ Leukemia or cancer
■ Seizures
■ Infectious etiology
■ Type B2: Toxins
■ Ethanol or methanol
■ Fructose and sorbitol
■ Epinephrine
■ Metformin
■ Type B3: Inborn errors of metabolism and hepatic fructose-biphosphate
deficiency
TREATMENT
■ Hydration as indicated
■ Support oxygenation and blood pressure as needed.
■ Treat infection.
■ Sodium bicarbonate should be reserved for extremely acidotic and deterio-
rating patients.
■ Thiamine for alcoholic patients
THYROID DISORDERS
PHYSIOLOGY
■ Hypothalamus releases thyrotropin releasing hormone (TRH) →anterior
pituitary releases thyroid stimulating hormone (TSH) →thyroid gland re-
leases T 3 and T 4.
■ Disorders are either 1°disorders of T 3 and T 4 production at the thyroid
gland or 2°disorders of the hypothalamus or pituitary.
Hypothyroidism and Myxedema Coma
ETIOLOGY
■ 1 °hypothyroidism by far most common.
■ Iatrogenic: Treatment of Graves disease with radiation or thyroidec-
tomy most common
■ Autoimmune disorders such as Hashimoto thyroiditis
ENDOCRINE, METABOLIC, FLUID, AND
ELECTROLYTE DISORDERS