0521779407-14 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:16
Metabolic Alkalosis 979
■determine if metabolic alkalosis is in setting of increased EABV or
decreased EABV (see differential diagnosis)
■identify and correct factors generating metabolic alkalosis (discon-
tinue diuretics, treat nausea and vomiting, remove source of excess
mineralocorticoid if possible)
■identify and correct factors maintaining metabolic alkalosis (volume
depletion, hypokalemia)
specific therapy
■decreased EABV and decreased total body Na
➣normal saline to replete extracellular fluid volume
➣replete potassium deficit
➣use of H2 blockers can minimize generation in nasogastric suc-
tion
➣correct Mg++deficit if present
■decreased EABV and increased total body Na (congestive heart fail-
ure, chronic obstructive pulmonary disease with right sided heart
failure)
➣acetazolamide (250–500 mg twice daily)
■increased EABV
➣treat underlying cause of mineralocorticoid excess if possible
➣if underlying cause cannot be corrected treat with K sparing
diuretic
➣Liddle’s syndrome use amiloride or triamterene, spironolactone
is ineffective
➣for metabolic alkalosis patients who require aggressive treat-
ment and maintenance factors cannot be corrected (critically
ill patients with pH > 7.55)
0.15 NaHCl infusion via central vein
ammonium chloride infusion: contraindicated in chronic liver
disease due to ammonia toxicity
frequent monitoring of arterial blood gas and serum elec-
trolytes are required with these therapies
follow-up
■monitor serum HCO3 and K to ensure alkalosis and hypokalemia are
corrected
■treat hypertension aggressively when present
■avoid hyperkalemia when using angiotensin converting enzyme
inhibitors or angiotensin receptor blockers with K sparing diuret-
ics