Iron supplementation for acute blood loss anemia after coronary artery bypass surgery: a randomized, placebo-controlled study.

Objective: To evaluate the use of oral iron replacement therapy as an effective treatment for acute surgically induced anemia.

Design: Double-blind, placebo-controlled, randomized clinical trial.

Setting: Perioperative acute care hospital and a surgery clinic for a single cardiothoracic physician group.

Patients: One hundred twenty-eight men and postmenopausal women, 50 years of age or older, admitted for elective coronary artery bypass surgery over a consecutive 8-month period.

Outcome Measures: Before surgery: serum iron, serum ferritin, hemoglobin and hematocrit. Six days after surgery: hemoglobin and hematocrit. Mean of 59 days after surgery: serum iron, serum ferritin, hemoglobin and hematocrit.

Intervention: Patients were randomized to one of four groups: control group; placebo group; low-dose group, 50 mg elemental iron + 60 mg ascorbic acid in a multi-vitamin daily; and usual-dose group, 200 mg elemental iron daily.

Results: One hundred twenty-one subjects completed the study: 100 men (82.6%) mean age 64.5 years and 21 women (17.4%), mean age 65.7 years. There were no statistically significant age or gender differences among groups. Statistical analysis revealed, except for side effects, no differences between or among groups for any variable measured during the last two time intervals. The mean hemoglobin and hematocrit of the entire sample at 6 days was 9.5 +/- 1.2 gm/dl and 28% +/- 2.3%, respectively. At a mean of 59 days later these values increased equally for all groups to a mean for the cohort of 13.6 +/- 1 gm/dl for hemoglobin and 40.6% +/- 3 for hematocrit. Serum iron and ferritin were within the normal range. The 200 mg group experienced significantly more side effects (p < 0.01).

Conclusion: Thus the use of oral iron supplements for the treatment of acute blood loss anemia after uncomplicated coronary artery bypass surgery did not assist in restoring red blood cell mass or help maintain total body iron stores.