Cold blood--potassium cardioplegia.

A technique is described for providing myocardial protection utilizing oxygenated blood that is drawn from the pump oxygenator and passed through two disposable cardioplegic cooling coils, which are joined in series and submerged in ice slush. A potassium-containing cardioplegic solution is run into the oxygenated blood at the level of the cooling coils. The amount of blood used in the blood-potassium cardioplegic mixture is controlled using a screw clamp. This method has been used with excellent results in 150 consecutive patients undergoing aortocoronary saphenous vein bypass grafting.