Hydrochloric acid infusion for treatment of metabolic alkalosis: effects on acid-base balance and oxygenation.

The effects of hydrochloric acid (HCl) administration were studied in 15 critically ill patients whose metabolic alkalosis caused a significant alkalemia (pH 7.50 to 7.58) unresponsive to sodium and potassium chloride administration. Arterial pH and bicarbonate and chloride concentrations normalized after a 6- to 12-h mean infusion of 200 +/- 54 mmol of .25 N HCl. There were no deleterious vascular, hematologic, or metabolic side-effects. HCl administration was associated with an increase in mean PaO2 from 94 +/- 21 to 121 +/- 31 torr (p less than .001). This increase was comparable in patients breathing spontaneously and those treated with controlled mechanical ventilation, and was attributed at least in part to a decrease in pulmonary shunt. These results indicate that .25 N HCl, infused at the rate of 100 ml/h into the superior vena cava, can correct metabolic alkalosis safely and rapidly. The persistence of the beneficial effects of this treatment on arterial oxygenation remains to be confirmed.