Nutrition support is increasingly recognized as a clinically relevant aspect of the intensive care treatment of cardiac surgery patients. However, evidence from adequate large-scale studies evaluating its clinical significance for patients’ mid- to long-term outcome remains sparse. Considering nutrition support as a key component in the perioperative treatment of these critically ill patients led us to review and discuss our understanding of the metabolic response to the inflammatory burst induced by cardiac surgery. In addition, we discuss how to identify patients who may benefit from nutrition therapy, when to start nutritional interventions, present evidence about the use of enteral and parenteral nutrition and the potential role of pharmaconutrition in cardiac surgery patients. Although the clinical setting of cardiac surgery provides advantages due to its scheduled insult and predictable inflammatory response, researchers and clinicians face lack of evidence and several limitations in the clinical routine, which are critically considered and discussed in this paper.

The aim of this study was to assess the prognostic value of different nutritional screening tools in patients undergoing cardiopulmonary bypass, with regard to adverse clinical outcome. This prospective cohort study analysed 1193 adult patients who underwent cardiopulmonary bypass. Patients were screened using five nutritional screening tools: Subjective Global Assessment (SGA), Nutritional Risk Screening 2002 (NRS-2002), Malnutrition Universal Screening Tool (MUST), Mini-Nutritional Assessment (MNA) and Short Nutritional Assessment Questionnaire (SNAQ). In-hospital mortality, postoperative complications, length of stay in intensive care unit and length of hospitalization were analysed. Multivariate backward logistic regression analysis was used to assess the independent predictive value of the studied screening tools. In accordance with univariate analysis, malnutrition detected by SNAQ, MUST, NRS-2002 and MNA was associated with postoperative complications (odds ratio [OR] 1.8, 95% confidence interval [95% CI] 1.3–2.4; OR 1.9, 95% CI 1.4–2.6; OR 1.8, 95% CI 1.2–2.9 and OR 1.9, 95% CI 1.4–2.6). Malnutrition detected by MUST, NRS-2002, MNA and SGA was associated with intensive care unit stay >2 days (OR 1.5, 95% CI 1.1–2.1; OR 2.3, 95% CI 1.5–3.7; OR 1.7, 95% CI 1.2–2.2 and OR 2.7, 95% CI 1.6–4.6). Prolonged hospitalization (>20 days) was predicted by SNAQ, MUST and MNA (OR 1.4, 95% CI 1–1.9; OR 1.6, 95% CI 1.2–2.2 and OR 1.6, 95% CI 1.2–2.2). In accordance with multivariate analysis, only MUST and MNA independently predicted postoperative complications (OR 1.6, 95% CI 1.1–2.3 and OR 1.6, 95% CI 1.1–2.2). Other independent factors influencing postoperative complications were well-known logistic EuroSCORE (OR 1.06, 95% CI 1–1.1) and the duration of cardiopulmonary bypass in minutes (OR 1.01, 95% CI 1–1.01). MUST and MNA both have independent predictive values with regard to postoperative complications. Taking into account simplicity, MUST is preferable for the cardiac surgical population.