Intravenous Hydrochloric Acid in Patients With Metabolic Alkalosis and Hypercapnia

• During a seven-year period, 15 patients admitted to an intensive care unit with a metabolic alkalosis resistant to saline and potassium chloride infusions and with an arterial pH of greater than 7.44 and arterial carbon dioxide pressure (Paco₂) of greater than 50 mm Hg, while breathing spontaneously, were given hydrochloric acid at 200 mmol/24 h through a central venous line until the arterial pH had decreased to less than 7.36 or Paco₂had decreased to less than 40 mm Hg. Five patients without respiratory failure had a significant decrease in Paco₂, pH, bicarbonate ion (HCO₃−), and base excess (BE). Four patients with acute respiratory failure had a significant decrease in Paco₂, HCO₃−, and BE and an increase in arterial oxygen pressure, indicating that in both of these patient groups alveolar ventilation had improved. Six patients with chronic respiratory failure had a significant decrease in pH, HCO₃−, and BE, although there was no significant change in Paco₂, indicating that in this patient group alveolar ventilation could not be consistently increased in response to a reduction in arterial pH. (Arch Surg1986;121:1195-1198)