Rho(D) immune globulin: Nursing pharmacology

Definitions & Key takeaways

RhO (D) immune globulin, also known as RhoGAM, is a medication that is most often used to prevent Rh isoimmunization in pregnant and postpartum clients. Isoimmunization happens when a pregnant individual with Rh-negative blood is exposed to Rh-positive fetal blood, resulting in the development of antibodies that can attack Rh-positive fetal blood cells. This can lead to hemolytic disease of the fetus and newborn or HDFN, with future pregnancies being at higher risk. So, it's important to remember to administer RhoGAM when indicated to prevent isoimmunization.

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Introduction0:00–1:30

RD immunoglobulin, or RHIG for short, is a biological class of medications primarily used in the management of RH negative pregnancies, which occur when the client has RH negative blood, while the fetus has RH positive blood.
The first RH negative pregnancy is usually not associated with complications, but in the following pregnancies, this RH incompatibility can cause severe life-threatening fetal complications.
What happens is that during delivery of the first RH negative pregnancy, some of the baby's red blood cells can get into the client's circulation.
Now, since the mother has RH negative red blood cells, her immune system recognizes the baby's RH positive red blood cells as foreign, and triggers the production of anti-RH antibodies.
At first, the mother produces IgM antibodies, which are too big to cross the placenta. Therefore, there are no complications during the first pregnancy.
But over time, the mother develops IgG anti-RH antibodies, which are smaller. As a result, if another RH negative pregnancy occurs, these pre-formed IgG antibodies are able to cross the placenta and destroy the fetal RH positive red blood cells.
This process is called RHisoimmunization and ultimately causes hemolytic disease of the fetus and newborn, or HDFN for short.
In order to prevent RH isoimmunization, all pregnant clients with RH negative blood should be given R D immunoglobulin, which can be administered intramuscularly.

Mechanism of action1:30–2:29

Once RD immunoglobulin is administered, it suppresses the mother's immune response and antibody formation against the fetus.
In fact, if the mother receives RD immunoglobulin within 72 hours postpartum, the chances of RH isoimmunization drop to 1 or 2%.
Moreover, if the mother receives RD immunoglobulin at 28 weeks of gestation, and then again within 72 hours of the delivery, the chance of developing RH isoimmunization becomes less than 1%.
Unfortunately, RD immunoglobulin is not effective when a client has already developed a positive antibody titer to the RH antigen.
Finally, it's important to note that mixing of maternal and fetal blood can occur during some obstetric complications, such as abortion, ectopic pregnancy, and placental abruption, as well as with some invasive obstetric procedures like amniocentesis.
These cases also require the administration of Roe immunoglobulin to prevent the possible formation of IgG anti-RH antibodies.
Now, the most common side effects associated with Rod immunoglobulin administration include headache, drowsiness, and dizziness, as well as vasodilation, hypotension, or hypertension.

Side effects2:29–2:54

Additionally, clients might develop reactions at the injection site such as erythema, mild pain and discomfort. Other side effects include drowsiness, pallor, fever, asthenia or weakness, and diaphoresis or excessive sweating.

Contraindications & cautions2:54–3:28

RD immunoglobulin is contraindicated in clients that have a history of previous anaphylaxis, or severe hypersensitivity reactions to human immunoglobulins.
Additionally, RH immunoglobulin might contain a small amount of IgA antibodies. Therefore, this medication should be avoided in clients with IgA deficiency.
This is because their immune system can recognize IgA antibodies as foreign and trigger a severe anaphylactic reaction. Finally, rhod immunoglobulin is contraindicated in RH positive clients because it can cause a hemolytic reaction.

Nursing considerations & client education3:28–4:54

Nurses are responsible for safely administering RD immunoglobulin or RHIG to prenatal or postpartum clients to prevent isoimmunization.
Before preparing the medication, review the client's medical record to ensure there are no contraindications to administration.
Confirm both the maternal and newborn's blood type and the maternal sensitization status. Because RHIG is made from human plasma, ensure that informed consent has been obtained and that the lot number and expiration date on the RHIG syringe match the lot number and expiration date on the blood bank paperwork.
Teach the client why RHIG is given and possible side effects such as fever, injection site soreness or irritation, dizziness or headache.
To administer RHIG choose an appropriate site for the volume of medication, such as the deltoid or anterolateral thigh, and administer the medication IM.
After administration, monitor the client for 20 minutes, observing for signs of hypersensitivity, including wheezing, rash, angioedema, hypotension, or tachycardia.
If you observe any of these signs, call for help and notify the physician immediately. After receiving RHIG teach the client that they should not receive a live vaccine such as MMR within 3 weeks, because it can interfere with the body's immune response to the RHIG.
Finally, explain that they may need to receive RD immunoglobulin with future pregnancies. Alright, as a quick recap, RD immunoglobulin is a biological medication that is most often used to prevent RH isoimmunization in pregnant and postpartum clients.

Review4:54–5:34

Isoimmunization happens when a pregnant client with RH negative blood is exposed to RH positive fetal blood, resulting in the development of antibodies that can attack RH positive fetal blood cells.
This can lead to hemolytic disease of the fetus and newborn, or HDFN, with future pregnancies being at higher risk. Nurses are responsible for safely administering RHIG to RH negative clients when indicated, ensuring that there are no contraindications, monitoring for signs of hypersensitivity, and providing client education.