DEVELOPMENT OF A POTASSIUM-SPECIFIC ADSORBENT FOR DIRECT HEMOPERFUSION

Direct hemoperfusion (DHP) over an exchange resin for sodium is capabl e of rapidly lowering an elevated serum potassium level but has not be en used clinically because of subsequent electrolyte abnormalities. Af ter the completion of detailed in vitro studies, we developed a sodium /calcium/magnesium exchange resin mixture specifically to remove potas sium from the blood. The mixture, which consisted of exchange resins f br sodium (48%), calcium (48%), and magnesium (4%), gave the most sati sfactory results in vitro. DHP through these resin-mixture columns for 2 h reduced elevated plasma potassium levels (6.7 +/- 1.1 to 3.5 +/- 0.6 mEq/L, p < 0.001) in anephric dogs without including any significa nt change in the levels of sodium, calcium, magnesium, albumin, total protein, or cholesterol. The platelet losses and changes in the plasma free hemoglobin levels observed were similar to those found with acti vated charcoal hemoperfusion. These results suggest that this resin he moperfusion may be useful in patients with acute hyperkalemia.