To improve the precision and reliability of estimates of the association between preoperative serum albumin concentration and surgical outcomes.
Prospective observational study. Patients were followed up for 30 days postoperatively. Multiple logistic regression models were developed to evaluate serum albumin level as a predictor of operative mortality and morbidity in relation to 61 other preoperative patient risk variables.
Forty-four tertiary care Veterans Affairs (VA) medical centers.
A total of 54,215 major noncardiac surgery cases from the National VA Surgical Risk Study.
Main Outcome Measures
Thirty-day operative mortality and morbidity.
A decrease in serum albumin from concentrations greater than 46 g/L to less than 21 g/L was associated with an exponential increase in mortality rates from less than 1% to 29% and in morbidity rates from 10% to 65%. In the regression models, albumin level was the strongest predictor of mortality and morbidity for surgery as a whole and within several subspecialties selected for further analysis. Albumin level was a better predictor of some types of morbidity, particularly sepsis and major infections, than other types.
Serum albumin concentration is a better predictor of surgical outcomes than many other preoperative patient characteristics. It is a relatively low-cost test that should be used more frequently as a prognostic tool to detect malnutrition and risk of adverse surgical outcomes, particularly in populations in whom comorbid conditions are relatively frequent.