Pre-operative serum albumin concentration as a predictor of mortality and morbidity following cardiac surgery

Pre-operative hypoalbuminaemia is associated with worse outcomes after non-cardiac surgery, but it has only recently been considered as a predictor of outcome in cardiac surgery. A multivariate analysis of data routinely collected from 400 patients undergoing cardiac surgery was undertaken, comprising pre-operative routine blood tests (serum concentrations of albumin, creatinine, alanine transaminase, alkaline phosphatase, bilirubin and haemoglobin, and white cell and platelet count), diabetic status, left ventricular function, gender, ethnicity, body mass index and age. Indices of outcome were death and length of stay (LoS) in cardiac intensive care and hospital. Eight percent of patients had baseline severe hypoalbuminaemia (serum albumin less than 30 g.L-1): these patients had longer intensive care and hospital stays and were more likely to die. Multivariate analysis revealed the best combination of predictors of length of hospital stay for the first 200 patients to be age, serum creatinine concentration, severe hypoalbuminaemia and diabetic state. However, in the second cohort of 200 patients, the same combination of predictors was not successful in predicting LoS in hospital.