| Popis: |
The objectives of every cardiac operation must be a technically perfect anatomic result and avoidance of intraoperative damage in pursuit of this goal. Nevertheless, perioperative myocardial damage remains the most common cause of morbidity and death following technically successful coronary bypass operation. This occurs whether the conduits are arterial or venous. Cardiac damage from inadequate myocardial protection leading to low output syndrome can prolong hospital stay, and may also result in delayed myocardial fibrosis leading to cardiac dysfunction months to years later [1, 2]. Cardioprotective strategies, like cardiac operations, have evolved to the point that it is essential to understand various techniques in order to limit intraoperative damage during a complicated operation. Surgeons must refrain from using simplistic cardioplegic protection strategies for the very reason that simplicity and safety are not synonymous. As with technical aspects of the surgical repair, the primary object of protection techniques is the use of the best strategy. Integration of surgical techniques is usually required to perform the best technical operation. Similarly, optimal myocardial protection also requires integration of various techniques to achieve the best results.Most surgeons would not abandon a complex surgical procedure (like all arterial revascularization) that was proved superior solely because of its lack of simplicity. Likewise, we should not choose a protection strategy for simplicity, unless it provides optimal and complete myocardial protection. Optimal myocardial protection is as important as an excellent technical repair in achieving the best long-term outcome with surgical correction. Although, the surgeonmight desire simplicity, the patient is only concerned with success. This chapter describes how oxygenated cardioplegia solutions can be delivered warm to allow their use for active resuscitation before ischemia is imposed, cold to limit damage, and again warm to avoid and reverse ischemic and reperfusion damage before and after aortic unclamping [1, 2]. It focuses primarily on the principles that form the basis for clinical strategies for cardioplegic delivery that can ensure that the selected cardioplegic solution can exert its desired effect, and it describes how these can be implemented. The described Table 6.1. Myocardial supply/demand balance during aortic cross-clamping |
