Technical refinements in myocardial protection: infants--adults.

Abstract

The aim of intraoperative protection is to prevent damage to function and structure of the myocardium. None of the methods employed today can guarantee this, on the other hand the result of any surgical intervention has to be regarded as a multifactorial process, myocardial function in particular depending on e.g. the preoperative state, the mode of protection, temperature of the patient, collateral flow, unloading of 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 1000ml of 2 degrees Bretschneider solution infusing it at rate of 80 - 120ml/min 8-10 minutes; in infants and children 40ml/kg as a single infusion are administered. The temperatures of the patients are various. As a result of myocardial protection, in the follow-up, besides survival, myocardial function should be a decisive parameter. Of particular interest are the results 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 accordance to the cardioplegic regimen used. Recent work has shown that reperfusion may aggravate the damage imposed on the heart during ischemia. An additional inflammatory reaction is observed which may compromise function. There is evidence that, under experimental and clinical conditions, the donation of nitric oxide may limit the amount of postischemic cardiac inflammation. Simple, safe, and reproducible myocardial protection together with careful, sophisticated, and perfect operative technique are the main requirements for successful cardiac surgery.