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Intrauterine RBC transfusion dosage

Donor red-cell volume for fetal intravascular transfusion.

Intrauterine RBC transfusion dosage
Estimated fetal weight
g
Fetal hematocrit (pre-transfusion)
%
Desired fetal hematocrit
%
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When to use

  • Estimating the donor packed-RBC volume for ultrasound-guided intrauterine intravascular transfusion of an anemic fetus (e.g., red-cell alloimmunization, parvovirus B19).

Formula

Transfusion volume (mL) = transfusion coefficient (0.02) x estimated fetal weight (g) x [(desired Hct - initial fetal Hct) / 10].

Pearls and pitfalls

  • The 0.02 mL/g coefficient was derived empirically and performed comparably to Mandelbrot's method and better than Plecas' method in the original validation.
  • Treat this as a pre-procedure estimate; the actual volume infused should be guided by real-time intraoperative hematocrit sampling.

References

  1. Giannina G, Moise KJ Jr, Dorman K. Fetal Diagn Ther. 1998;13(2):94-97.