Carbon dioxide buffering in man

¹ Cardiopulmonary and Renal Research Laboratories, Georgetown Medical Division, D.C. General Hospital; and the Department of Medicine, Georgetown University Medical Center, Washington, D.C.

The administration of tris-(hydroxymethyl)aminomethane (THAM) to six normal adults was followed by a series of changes in ventilation, arterial blood and urine. Alveolar ventilation and oxygen saturation fell significantly, as did alveolar CO₂ excretion and tidal volume. Alveolar and blood CO₂ tension rose slightly. Blood bicarbonate rose while other electrolytes were essentially unchanged. Urinary pH and electrolyte excretion increased strikingly without any change in endogenous creatinine clearances. No toxic effects were observed. The findings suggest that THAM cannot presently be recommended for clinical use in the treatment of respiratory acidosis, unless some means of stimulating respiration are also provided.