Metabolic alkalosis, hypokalemic

By inhibiting salt reabsorption in the TAL, loop diuretics increase delivery to the collecting duct. Increased delivery leads to increased secretion of K+ and H+ by the duct, causing hypokalemic metabolic alkalosis (Table 15-2). This toxicity is a function of the magnitude of the diuresis and can be reversed by K+ replacement and correction of hypovolemia. 

Na/K/2CI transporter in the ascending limb of Henle s loop excretion, some wasting, hypokalemic metabolic alkalosis, increased urine Ca and Mg peripheral edema, hypertension, acute hypercalcemia or hyperkalemia, acute renal failure, anion overdose duration of action 2-4 h Toxicitiy Ototoxicity, hypovolemia, wasting, hyperuricemia, hypomagnesemia... 

Hydrochlorothiazide Inhibition of the Na/CI transporter in the distal convoluted tubule Modest increase in NaCI excretion some wasting hypokalemic metabolic alkalosis t decreased urine Ca Hypertension, mild heart failure, nephrolithiasis, nephrogenic diabetes insipidus Oral duration 8-12 h Toxicity Hypokalemic metabolic alkalosis, hyperuricemia, hyperglycemia, hyponatremia... 

Reversible hypokalemic metabolic alkalosis and hypomagnesemia can occur with gentamicin, and routine monitoring has been recommended (79). 

Shetty AK, Rogers NL, Mannick EE, Aviles DH. Syndrome of hypokalemic metabolic alkalosis and hypomagnesemia associated with gentamicin therapy case reports. Clin Pediatr (Phila) 2000 39(9) 529-33. 

Hjq)onatremia is rare, and persistent hyponatremia very rare in patients taking cisplatin (162). In a detailed description of the biochemical abnormalities that can result from renal tubular dysfunction after cisplatin therapy, it was noted that hypocalciuria is more common than hypomagnesemia, and that there tends to be a state of reduced serum bicarbonate. The most severe renal tubular damage caused by cisplatin is characterized by hypocalciuria, total body magnesium deficiency, and hypokalemic metabolic alkalosis (163). 

A woman who had taken Carter s Little Pills , which contained aloe and podophyllum, daily for 4 yr presented with unexplained hypokalemic metabolic alkalosis (Ramirez and Marieb, 1970). Carter s Little Pills have since been reformulated and no longer contain aloe. 

Ramirez B, Marieb NJ. Hypokalemic metabolic alkalosis due to carter s little pills. Conn Med 1970 34 169-70. 

Hypokalemic metabolic alkalosis A shift in body electrolyte balance and pH involving a decrease in serum potassium and an increase in blood pH. Typical result of loop and thiazide diuretics... 

Toxicity Loop diuretics usually induce hypokalemic metabolic alkalosis. Because large amounts of sodium are presented to the collecting tubules, wasting of potassium (which is excreted by the kidney in an effort to conserve sodium) may be severe. Because they are so efficacious, the loop diuretics can cause hypovolemia and cardiovascular complications. Ototoxicity is an important toxic effect of the loop agents. The sulfonamides in this group may cause typical sulfonamide allergy. 

B. Effects In full doses, thiazides produce moderate but sustained sodium and chloride diuresis. Hypokalemic metabolic alkalosis may occur (Table 15-2). Reduction in the transport of sodium into the tubular cell reduces intracellular sodium and promotes sodium-calcium exchange. As a result, reabsorption of calcium from the urine is increased and urine calcium content is decreased— the opposite of the effect of loop diuretics. Because they act in a diluting segment of the nephron, thiazides may interfere with excretion of water and cause dHutional hyponatremia. 

Electrolyte balance Aminoglycosides cause fluid, electrolyte, and acid-base disorders by altering renal tubular function in several ways, leading to hypokalemia and acidosis or alkalosis. Stimulation of the calcium-sensing receptor has been reported to cause a Bartter-like syndrome (hypokalemic metabolic alkalosis, hypomagnesemia, hypocalcemia, and normal serum creatinine concentrations). More rarely, a proximal renal tubular acidosis (Fanconi syndrome non-anion gap metabolic acidosis) can develop. The mechanisms have been summarized [4 ]. 

Amiloride (Midamor) Directly increases Na+ excretion and decreases K+ secretion in distal convoluted tubule. Used with other diuretics because K+-sparing effects lessen hypokalemic effects. May correct metabolic alkalosis. HYPERkalemia, sodium or water depletion. Patients with diabetes mellitus may develop glucose intolerance. 

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