TECHNICAL REFINEMENTS IN MYOCARDIAL PROTECTION - INFANTS-ADULTS

The aim of intraoperative protection is to prevent damage to function and structure of the myocardium. None of the methods employed today ca n guarantee this, on the other hand the result of any surgical interve ntion has to be regarded as a multifactorial process, myocardial funct ion in particular depending on e.g. the preoperative state, the mode o f protection, temperature of the patient, collateral flow, unloading o f the left ventricle, and other factors during ischemic arrest. Daily use of cardioplegic solutions requires standardized procedures keeping it safe and simple. Thus we use in adults 1000 ml of 2 degrees Bretsc hneider solution infusing it at rate of 80 - 120 ml/min 8-10 minutes; in infants and children 40 ml/kg as a single infusion are administered . The temperatures of the patients are various. As a result of myocard ial protection, in the follow-up, besides survival, myocardial functio n should be a decisive parameter. Of particular interest are the resul ts in patients with preoperatively reduced myocardial function and the effect of myocardial protection techniques. In addition, examples of long-term survivors after congenital operations will be discussed in a ccordance to the cardioplegic regimen used. Recent work has shown that reperfusion may aggravate the damage imposed on the heart during isch emia. An additional inflammatory reaction is observed which may compro mise function. There is evidence that, under experimental and clinical conditions, the donation of nitric oxide may limit the amount of post ischemic cardiac inflammation. Simple, safe, and reproducible myocardi al protection together with careful, sophisticated, and perfect operat ive technique are the main requirements for successful cardiac surgery .