Chapter 046. Sodium and Water (Part 12) potx

Chapter 046. Sodium and Water
(Part 12)

Table 46-3 Causes of Hypokalemia
I. Decreased intake
A. Starvation
B. Clay ingestion

II. Redistribution into cells
A. Acid-base
1. Metabolic alkalosis


B. Hormonal
1. Insulin
2. β
2
-
Adrenergic agonists (endogenous or
exogenous)
3. α-Adrenergic antagonists

C. Anabolic state
1. Vitamin B
12
or folic acid (red blood cell
production)
2. Granulocyte-
macrophage colony stimulating
factor (white blood cell production)
3. Total parenteral nutrition

D. Other
1. Pseudohypokalemia
2. Hypothermia
3. Hypokalemic periodic paralysis

4. Barium toxicity

III. Increased loss
A. Nonrenal
1. Gastrointestinal loss (diarrhea)
2. Integumentary loss (sweat)

B. Renal

1. Increased distal flow: diuretics, osmotic
diuresis, salt-wasting nephropathies
2. Increased secretion of potassium

a. Mineralocorticoid excess: primary
hyperaldosteronism, secondary
hyperaldosteronism (malignant hypertension,
renin-
secreting tumors, renal artery stenosis,
hypovolemia), apparent mineralocorticoid
excess (licorice, chewing tobacco,
carbenoxolone), congen
ital adrenal
hyperplasia, Cushing's syndrome, Bartter's
syndrome

b. Distal delivery of non-
reabsorbed
anions: vomiting, nasogastric suction, proximal
(type 2) renal tubular acidosis, diabetic
ketoacidosis, glue-
sniffing (toluene abuse),
penicillin derivatives

c. Other: amphotericin B, Liddle's
syndrome, hypomagnesemia