Tham Solution is indicated for the prevention and correction of metabolic acidosis. In the following conditions it may help to sustain vital functions and thus provide time for treatment of the primary disease: Metabolic Acidosis Associated with Cardiac Bypass Surgery. Tham Solution has been found to be primarily beneficial in correcting metabolic acidosis which may occur during or immediately following cardiac bypass surgical procedures. Correction of Acidity of ACD Blood in Cardiac Bypass Surgery. It is well known that ACD blood is acidic and becomes more acidic on storage. Tromethamine effectively corrects this acidity. Tham Solution may be added directly to the blood used to prime the pump-oxygenator. When ACD blood is brought to a normal pH range the patient is spared an initial acid load. Additional tromethamine may be indicated during cardiac bypass surgery should metabolic acidosis appear. Metabolic Acidosis Associated with Cardiac Arrest. Acidosis is nearly always one of the consequences of cardiac arrest and, in some instances, may even be a causative factor in arrest. It is important therefore, that the correction of acidosis should be started promptly with other resuscitative efforts. By correcting acidosis, Tham Solution has caused the arrested heart to respond to resuscitative efforts after standard methods alone had failed. In these cases, tromethamine was given intraventricularly. It is to be noted, however, that such precariously ill patients often have died subsequently of causes unrelated to the administration of tromethamine. With administration by the peripheral venous route, metabolic acidosis has been corrected in a majority of patients. The success in reinstitution of cardiac rhythm by this means probably has not been of the same order of magnitude as with the intraventricular route.