Hypoxia, reoxygenation and the role of systemic leukodepletion in pediatric heart surgery

Abstract

As cardiopulmonary bypass (CPB) in infants and neonates is becoming more frequent, the technical performance of these operations for congenital heart disease has made significant progress. However, little research has been carried out into the conduct of CBP in producing myocardial and pulmonary dysfunction. Postoperative organ dysfunction is a problem, particularly for cyanotic infants. This paper examines the experimental and clinical experience of injury brought about by abrupt reoxygenation of the hypoxic, or cyanotic, heart. The modalities of gradual reoxygenation and leukodepletion in limiting this injury are examined, leading to the conclusion that injury can be reduced and possibly ameliorated by changes in intraoperative management during CBP in children with cyanotic disease.

Hypoxia-Induced Molecular and Cellular Changes in the Congenitally Diseased Heart: Mechanisms and Strategies of Intervention

“…Furthermore, the effect of leukodepletion was examined in this study, in order to verify whether the removal of an important source of ROS, the white blood cells, would minimize the reoxygenation injury. The depletion of leukocytes from the blood-reduced oxygen free radical formation and preserved ventricular contractility at similar extent to the one achieved by controlled reoxygenation [55].…”

“…In the reperfused heart, this oxidant formation derives form a series of interacting pathways in cardiac myocytes and endothelial cells, which involve also leukocyte chemotaxis and inflammation. The white blood cells are, in fact, another great source of ROS: when activated by the binding to the hypoxic endothelium, they produce chemotactic substances and oxygen radicals, which are the main responsible for cellular damage [55]. In addition, nitric oxide (NO) production is greatly increased in post-ischemic hearts, thus impairing vascular reactivity [56].…”

“…Clinical studies have shown that, despite similar cross-clamp times during open heart surgery, cyanotic children have worse clinical outcome and more reoxygenation injury, measured by troponin I release, compared with acyanotic children [11]. The major problem arises from the oxygen reintroduction during the cardiopulmonary bypass (CPB), which is a necessary procedure for the surgical management of CHDs [55]. As the chronic hypoxia produces long-term changes in the myocardial metabolism and function, the sudden oxygen reintroduction further exacerbates these effects.…”

Influence of the type of congenital heart defects on epithelial lining fluid composition in infants undergoing cardiac surgery with cardiopulmonary bypass

“…Surgical repair of CHD with or without cardiopulmonary bypass (CPB) can also lead to a lung insult, extending from microscopic atelectasis to fulminant acute respiratory distress syndrome (5,6), by the activation of a systemic inflammatory response (7). In addition, during CPB, the lungs are collapsed and pulmonary blood derives only from the bronchial arteries.…”

Cytoflavin as an Additional Method for Myocardial Salvage During Operations Under Extracorporeal Circulation

“…Предложено большое количество препаратов и методов для предотвращения повреждающего дей ствия на организм гипоксии и окислительного стресса, в том числе и экстракорпоральных. Для уве личения антиоксидантной активности плазмы пред ложено использовать лазерное облучение [4,5], лейкоцитарные фильтры после искусственного кро вообращения [6], а так же препараты, относящиеся к антиоксидантам и антигипоксантам [7,8].…”