Updates and Clarifications RhoGAM® Updates and Clarifications

RhoGAM® description Contains IgG anti-D (anti-Rho) Prevents Rh alloimmunization Manufactured from human plasma that contains anti-D A single 300mcg dose will suppress the immune response to 15 ml of Rh-positive RBCs (approx 30 mL whole blood)

Mechanism of Action Suppresses the immune response of Rh-negative individuals to Rh-positive RBC’s How it does this is not known Is not effective once Rh alloimmunization has occurred

Use in Obstetrics Rh-negative pregnant patient may be exposed to RBC’s from her Rh-positive fetus Can happen during the normal course of pregnancy or After procedures or abdominal trauma Given at 28 weeks And within 72 hrs. of delivery

Obstetrical procedures Pregnancy/delivery of Rh-positive fetus irrespective of ABO groups of either mom or baby Abortion/threatened abortion at any point in pregnancy Ectopic pregnancy Amniocentesis, chorionic villus sampling, percutaneous umbilical blood sampling, versions or abdominal trauma

Use after Rh Incompatible Transfusion Individuals transfused with Rh-positive RBC’s have an 80% likelihood of producing anti-D This may occur when there are not enough Rh-negative platelets available and Rh-positive units are used Rh alloimmunization can occur after exposure to <0.1 ml of Rh-positive blood RhoGAM® should be administered within 72 hrs. of this exposure

Precautions For I.M. use only Observe patient for 20 minutes after injection Allergic responses may occur (extremely rare) Inform patient to report early signs of hypersensitivity, hives, generalized urticaria, tightness of the chest, wheezing, hypotension and anaphylaxis Treatment depends on severity of reaction

More precautions Never give RhoGAM® to baby Some babies born of women given RhoGAM® have weakly positive direct antiglobulin (Coombs) tests at birth Fetal-maternal hemorrhage may cause false blood typing results in mom When there is any doubt as to pt.’s blood type, RhoGAM® should be administered

Antepartum Procedure In addition to the 28 week prophylactic dose Patients may receive additional doses prior to delivery If they have had a bleed, trauma, procedure etc., they will be given RhoGAM® If RhoGAM® is administered for any indication in early pregnancy, there is an obligation to maintain levels of passively acquired anti-D by giving RhoGAM® at 12-week intervals The anti-D will be present in the blood for a few weeks after administration and may show a positive ABS This is the passive anti-Rh antibody and does not disqualify pt. from receiving additional injections of RhoGAM® as prescribed by HCP

“What if my patient received RhoGAM® within 3 weeks prior to delivery You will still send the mom’s blood to lab after delivery PP dose may be withheld after a negative test for FMH (fetal maternal hemorrhage) FMH test determines if exposure to > 15 mL of fetal RBC’s has occurred Additional doses of RhoGAM® will be required if an FMH exceeds 15 mL This event is unlikely to occur prior to the third trimester and is most likely to happen after birth

Procedure to follow with Rh-negative mother Determine mom is a RhoGAM® candidate Fill out fluorescent red sticker entitled “RhoGAM® Candidate” and place on yellow In pt. progress notes Send cord blood to lab with Blood Bank requisition all stamped with BABY’s name Mark on requisition: √ Rh Immune Globulin Evaluation (under Infant studies box)  Blood Bank will call to notify nurse of baby’s blood type

Procedure continued Baby is Rh-negative, inform mom and do nothing else

Procedure continued Baby is Rh-positive √ Verify mother is willing to receive RhoGAM® (it is a blood product) √ Collect blood from mom in pink top tube √ Send blood with BB requisition with Rh Immune Globulin (IM 300 mcg) checked stamped with Mom’s information √ BB will call when RhoGAM® is ready for patient √ BB will send the correct amount of RhoGAM® to be given √ Rarely will this amount be more than one injection √ RhoGAM® needs to be given within 30 minutes of arriving on unit √ Fill out Patient Identification Card and give to patient

Rh sensitized patients Patient’s who are already sensitized will not receive RhoGAM® . They are already producing the antibodies. The antibodies she is now producing will destroy any Rh-positive cells that are present

Last Words Filling out RhoGAM® Control Form The form is self explanatory Both the lot number and the bar coded vial number should be recorded on the Form If you have problems with it, see me or a preceptor for answers

Sheila Mangiaracina, RN July, 2004 Authors Kathy Lemenu, RN Sheila Mangiaracina, RN July, 2004 Please email comments, questions to either Kathy or Sheila.