Albumin Volume Expansion Lowers Mortality After Bypass Surgery

NEW YORK (Reuters Health) – Volume expansion with albumin brings lower mortality rates than does nonprotein colloid volume expansion after coronary artery bypass graft (CABG) surgery, according to a report in the June issue of Chest.

Blood volume expanders are often used to enhance intravascular blood volume, improve hemodynamics, and reduce the need for blood transfusions perioperatively, the authors explain, but nonprotein colloids are associated with an increased risk of bleeding complications.

Dr. John Elefteriades from Yale University School of Medicine in New Haven, Connecticut and colleagues used data from the Solucient Clinical Pathways Database from nearly 20,000 patients undergoing CABG surgery to determine if albumin use (8084 patients) was associated with lower mortality rates than was nonprotein colloid use (11,494 patients).

In a simple, bivariate comparison, mortality among patients who received albumin (2.47%) was lower than that among patients who received nonprotein colloids (3.03%), the authors report.

Moreover, in a multivariable logistic regression analysis that adjusted for 16 covariates, albumin use was associated with significantly lower odds of mortality compared with nonprotein colloid use (odds ratio, 0.80).

“Thus,” the investigators write, “when albumin rather than nonprotein colloids was used, approximately five to six lives were spared for every 1000 patients who underwent CABG surgery.”

Mortality was higher in association with female gender, age, low-volume hospitals, emergency admission, simultaneous valve procedure, and peripheral vascular disease, the researchers note, whereas lower mortality risk was associated with mammary grafting.

Based on their hospital charges of $415 for albumin and $117 for nonprotein colloids, the authors estimate that albumin use would result in a cost of $52,000 to $54,000 per life saved.

“The use of albumin for volume expansion appears to be associated with a reduced incidence of mortality after CABG surgery when compared to nonprotein colloid treatment,” the investigators conclude. “Further clinical studies are warranted to substantiate these results with better definitions of variables and to develop evidence-based guidelines for colloid administration.”

Chest 2003;123:1853-1857.