WinRho (Rho(D) Immune Globulin) Administration Protocol
WinRho should be administered intravenously (IV) when possible, especially in thrombocytopenic patients, at a dose of 25 mg (125 IU) per 1 mL of RBC exposure, given before or immediately after transfusion, though it remains effective if given within 72 hours. 1
Indications for WinRho Administration
WinRho (Rho(D) immune globulin) is indicated for:
- Prevention of RhD alloimmunization in RhD-negative individuals exposed to RhD-positive blood
- Prevention of hemolytic disease of the newborn in subsequent pregnancies
- Prevention of alloimmunization following platelet transfusions containing RhD-positive RBCs
Administration Protocol
Route of Administration
- Preferred route: Intravenous (IV) administration, especially in thrombocytopenic patients 1
- Alternative route: Intramuscular (IM) if IV preparation is unavailable
Dosing Guidelines
- Standard dose calculation: 25 mg (125 IU) of WinRho protects against 1 mL of RhD-positive RBCs 1
- For platelet transfusions: Dose depends on the number of contaminating RBCs in the platelet concentrate
Timing of Administration
- Optimal timing: Before or immediately after exposure to RhD-positive blood 1, 2
- Effective window: Within 72 hours of exposure 1, 2
- May still provide some protection if given up to 28 days after exposure 3
Special Populations and Considerations
Obstetric Patients
- Antepartum: 300 mcg at 28 weeks' gestation 4
- Postpartum: 300 mcg within 72 hours after delivery of an RhD-positive infant 4
- Early pregnancy events (<12 weeks): 50-120 mcg 4
- Events after 12 weeks: 300 mcg 3
Oncology Patients
- For RhD-negative patients receiving platelet transfusions from RhD-positive donors:
Monitoring and Follow-up
- No specific monitoring is required after administration
- For large feto-maternal hemorrhage or multiple transfusions, additional doses may be needed
- Testing to quantify fetal-maternal hemorrhage may be considered in certain high-risk situations 3
Potential Pitfalls and Caveats
- Do not administer to RhD-positive individuals or those with "weak D" (Du-positive) status 3
- Ensure proper timing - effectiveness decreases significantly after 72 hours
- One dose may protect against several platelet transfusions depending on RBC contamination level 1
- Verbal or written informed consent should be obtained prior to administration 3
- In supply shortages, prioritize postpartum patients and those at later gestational ages 4
Efficacy and Safety
- Studies show that proper administration of WinRho is highly effective in preventing RhD alloimmunization 5, 6
- Both IV and IM routes appear equally effective in preventing alloimmunization, though IV administration results in higher immediate anti-D levels 7
- WinRho has been found to be nonpyrogenic, nontoxic, and safe when administered correctly 5
By following this protocol for WinRho administration, healthcare providers can effectively prevent RhD alloimmunization and its associated complications, including hemolytic disease of the fetus and newborn in subsequent pregnancies.