LAB UNIT 1 EXAM REVIEW HDN QS

Summary

The transcript discusses hemolytic disease of the newborn (HDN), highlighting its causes, effects, and treatments. It explains how maternal antibodies can attack fetal red blood cells, leading to conditions like jaundice and potential cardiac failure in the infant. The discussion includes the mechanisms of sensitization during pregnancy, particularly focusing on Rh incompatibility and blood type interactions. Preventative treatments like Rhogam are outlined, emphasizing their role in preventing sensitization. The video also touches on various complications and treatment strategies, including phototherapy and blood transfusions, making it a comprehensive overview of HDN and its implications for maternal and fetal health.

Takeaways

• 😀 HDN stands for Hemolytic Disease of the Newborn, which involves the destruction of fetal red blood cells due to maternal antibodies.
• 🩸 The primary cause of HDN is Rh incompatibility, where an Rh-negative mother produces antibodies against Rh-positive fetal blood cells.
• 🌬️ Hypoxia occurs when fetal tissues receive insufficient oxygen, potentially leading to severe tissue and cardiovascular complications.
• 🧠 Kernicterus can result from high bilirubin levels, causing damage to the nervous system due to excessive hemolysis.
• 👶 Maternal antibodies, particularly IgG, can cross the placenta and attack fetal red blood cells, leading to their destruction.
• 🚨 Jaundice may appear in newborns due to elevated unconjugated bilirubin levels, which can occur before or after birth.
• 🔬 RhoGAM injections are given to Rh-negative mothers to prevent sensitization and subsequent hemolytic disease in future pregnancies.
• 💉 In cases where the baby is born with HDN, treatments include phototherapy to lower bilirubin levels and administering Rh-negative blood transfusions.
• 📊 Testing for Rh antibodies in mothers can be done using direct ELISA tests to determine if sensitization has occurred.
• 🩹 Other blood group incompatibilities, like ABO incompatibility, can lead to HDN, but they are generally less severe than Rh incompatibility.

Q & A

What does the abbreviation 'HDN' stand for?

HDN stands for Hemolytic Disease of the Newborn, which involves the destruction of fetal red blood cells.

What causes hemolysis in the context of HDN?

Hemolysis occurs when the mother's antibodies attack the fetal red blood cells due to an immune response triggered by the presence of antigens on those cells.

What type of bilirubin is typically high in newborns with HDN, and why?

Newborns with HDN typically have high levels of unconjugated bilirubin because the immature liver struggles to conjugate bilirubin effectively due to the hemolysis.

What is kernicterus, and how is it related to HDN?

Kernicterus is a form of brain damage caused by high levels of bilirubin in the blood, leading to neuronal damage in infants with HDN.

How can a mother become sensitized to her baby's blood type?

A mother can become sensitized to her baby's blood type during pregnancy if there is a transplacental tear, allowing fetal red blood cells to enter her bloodstream.

What is the significance of the Rh factor in HDN?

The Rh factor is significant because if an Rh-negative mother carries an Rh-positive baby, she may produce antibodies against the Rh antigen, leading to hemolysis of the baby's red blood cells.

What is RhoGAM, and what role does it play in preventing HDN?

RhoGAM is an injection of anti-Rh antibodies given to Rh-negative mothers to prevent sensitization to Rh-positive fetal blood cells and to reduce the risk of HDN in future pregnancies.

How does the severity of HDN due to ABO incompatibility compare to that due to Rh incompatibility?

HDN due to ABO incompatibility is generally less severe than that due to Rh incompatibility because the antibodies involved in ABO incompatibility do not affect all fetal red blood cells as severely as Rh antibodies.

What treatment options are available for a baby born with HDN?

Treatment options for a baby born with HDN include phototherapy to reduce bilirubin levels and blood transfusions, typically with Rh-negative blood, to manage hemolysis.

Can an Rh-positive mother have an Rh-negative baby, and does she need RhoGAM in that case?

Yes, an Rh-positive mother can have an Rh-negative baby, and she does not need RhoGAM because she is not at risk of producing antibodies against Rh-positive blood.