When is it to appropriate to discontinue providing leukoreduced and irradiated cellular components for pediatric cardiac bypass patients after surgery?

A Transfusion Medicine physician working at a Pediatric Hospital in South America writes: "We currently use leukoreduced and irradiated cellular components for patients under one year of age undergoing cardiac bypass surgery, but discontinue using these components once the patient is transferred to ICU. During a meeting of the Transfusion Committee, the physician from Intensive Care Unit asked the rest of the committee members why we stop using leukoreduced and irradiated components after the patient is disconnected from the pump and transferred to ICU." Does the immunological state of the patient change when the patient left the Operating Room? What do other facilities do?

The following comments have been received.

ADDENDA June 11, 2007

1. A transfusion medicine physician in New York reports that in her experience at least one compelling reason for the use of leukoreduced and irradiated blood products during pediatric cardiac surgery cases is to avoid transfusing unirradiated blood products to a patient with undiagnosed (unrecognized) Di George syndrome (estimated to be present 1 in 6000 live births), associated with a 22q11 deletion. She reports that at least seventy five percent of patients with Di George syndrome have congenital cardiac defects, and the presence of the syndrome may not be discovered until the time of surgery when the absence or hypoplasia of the thymus is appreciated. She adds that the pediatric cardiac surgeons at her hospital do not want to first discover that a patient has Di George syndrome during surgery after unirradiated blood products have already been transfused or unirradiated blood products are already set up in the lab for imminent use. Consequently, they transfuse irradiated leukodepleted blood to all children under the age of two for this reason, and because of other possible undiagnosed immunodeficiency syndromes. She reports that they "asked around at several children's hospitals on the East coast and followed their lead". She concludes saying that the surgeons in South America who initiated this discussion may be switching their patients back to non-irradiated blood products once they have observed that the patients have a normal appearing thymus.

References:

• Oskarsdottir S et al, Presenting phenotype in 100 children with the 22q11 deletion syndrome. Eur J Pediatr. 2005 Mar;164 (3):146-153.
• Botto LD et al. A population-based study of the 22q11.2 deletion: phenotype, incidence and contribution to major birth defects in the population. Pediatrics. 2003 Jul; 112 (1 Pt 1):101-7.

Please submit comments to the e-Network Forum.

Ira A. Shulman, MD
CBBS e-Network Forum Editor & Moderator

W. Tait Stevens, MD
CBBS e-Network Forum Assistant Editor & Moderator