Background: Recombinant human erythropoietin is now available for clinical use. Therefore we sought to determine the frequency of anemia and low endogenous erythropoietin levels in patients undergoing elective, major general surgical procedures.
Methods: Serum immunoreactive erythropoietin levels were measured before operation and 1 and 5 days after operation in 84 patients (43 men and 41 women) with normal renal function.
Results: Twenty of the women (49%) and 27 of the men (63%) were anemic before operation. Nine of these anemic patients had inappropriately low serum erythropoietin levels for their degree of anemia. On postoperative day 1, 66% of the women and 88% of the men were anemic, but the mean serum erythropoietin level had not increased. On postoperative day 5, 80% of the women and all of the men were anemic, but 22% of the patients still had an inappropriately low serum erythropoietin level. Multiple regression analysis identified female gender and black ancestry as predictors of an inadequate erythropoietin response after operation.
Conclusions: Diseases requiring operation are frequently associated with anemia that is in part caused by impaired erythropoietin production. Surgery also appears to contribute to suppression of erythropoietin production particularly in women and black persons.