**1. Introduction**

324 Perioperative Considerations in Cardiac Surgery

Zhou, R. & Liu, J. (2011). A Risk Factor for Hyperlactatemia After Surgical Repair of

*Thoracic and Cardiovascular Surgery,* Vol.141, No.2, pp. 598-599.

Secundum Atrial Septal Defect in Children: What Is The Problem? *Journal of* 

Critically ill states, perioperative period of major surgery, particularly cardiac operations are often encountered with large hemodynamic alterations and fluid shifts. Cardiac failure in patients with congenital heart defect has heterogeneous origin therefore diagnosis related treatment is difficult to apply. During the postoperative period, hemodynamic instability has multifactorial origin and cardiorespiratory dysfunction has several manifestation e.g. myocardial dysfunction, pulmonary hypertension etc (Laussen & Roth, 2003).

Biochemical markers play an important role in the risk stratification of patients with cardiovascular disease. Elevated brain natriuretic peptide level has been shown to reveal congestive heart failure among adult patients admitted to emergency department with dyspnoe (Maisel et al, 2002; de Lemos et al, 2001), and to predict adverse events in acute coronary syndromes (de Lemos et al, 2001). Cardiac troponin, creatine kinase-MB, brain natriuretic peptide and C-reactive protein have been shown to predict mortality and morbidity in unstable coronary artery disease (Lindahl et al, 2000). In patients with pulmonary embolism, brain natriuretic peptide and other cardiac markers, such as troponin predict adverse outcomes much more accurately than any other clinical signs (Kucher et al, 2003). In the last decade, several papers investigating the prognostic, diagnostic and therapeutic relevance of natriuretic peptides in the pediatric population have been published (in rev. Cantinotti et al, 2011; Cantinotti et al, 2011).
