[Blood transfusion during heart surgery. A retrospective nested case-control study]

To assess the correlation between intraoperative packed red blood cells transfusion and adverse outcome in a Spanish cohort of cardiac surgery patients.

Retrospective observational multicentre study. An analysis was performed on the data from 927 cardiac surgery patients treated in 24 Spanish hospitals in 2007. Patients who received intraoperative transfusions were compared with non-transfused patients. Multivariate analyses were performed (including, among others, several items from the Euroscore, surgery type, basal renal status and haemoglobin levels, and Thakar score).

Every transfusion of packed red cells was associated with increased postoperative risk of acute kidney damage at 72 hours after surgery, prolonged mechanical ventilation, and need for haemodynamic support. Moreover, transfused patients showed an increased in-hospital mortality rates (Adjusted OR: 1.30; 95% CI: 1.19-1.42), as well as longer hospital stays (almost 4 days).

In this cohort of patients, intraoperative transfusion might independently predict higher risk of early acute kidney damage, prolonged postoperative mechanical ventilation, and a need for haemodynamic support, and reduced short term survival (adjusted OR for mortality: 1.30; 95% CI: 1.19-1.42), and longer hospital stays (4 days longer).