EMT Class - Placenta Previa and Placental Abruption Notes

Placenta Previa
  • Definition: Placenta previa occurs when the placenta attaches to the lower part of the uterus, partially or completely covering the internal cervical os (the opening through the cervix).
  • Significance in Pregnancy:
    • Initially, placenta previa is not a significant concern but becomes critical later in pregnancy as contractions begin.
    • Braxton Hicks contractions can disturb the improperly placed placenta, potentially leading to complications.
  • Consequences of Labor:
    • During labor, as the cervix dilates, it can tear the interface between the placenta and uterine wall, leading to bleeding.
    • A fetus passing through the birth canal can rupture the placenta, causing trauma and severe bleeding.
  • Risks:
    • Not a life threat during most of pregnancy but can lead to significant complications during contractions and dilation.
    • Severe preterm bleeding may require cesarean delivery, which carries its own risks.
Risk Factors for Placenta Previa
  • Multiple Gestation: More fetuses lead to limited space for proper placenta placement.
  • Advanced Maternal Age: Women over 35 years are at increased risk.
  • History of Previous Previa or Cesarean Delivery: Increased likelihood of recurrence.
  • Maternal Smoking and Drug Use:
    • Substances like cocaine result in vasoconstriction, reducing blood supply to the placenta.
  • Vaginal Bleeding History: Previous vaginal bleeding during pregnancy can indicate previa.
Classic Signs and Symptoms
  • Presenting Symptoms:
    • Painless, third-trimester vaginal bleeding
    • Any vaginal bleeding after 20 weeks gestation should raise suspicion of previa.
  • Hypovolemic Shock:
    • Severe bleeding can lead to symptoms of shock, like lethargy or low blood pressure, requiring immediate attention.
Placental Abruption
  • Definition: Placental abruption occurs when the placenta detaches from the uterine wall, leading to severe hemorrhage.
  • Consequences:
    • Tearing the placenta disrupts blood vessels, leading to uncontrolled internal bleeding.
    • This can threaten both maternal and fetal life.
Risk Factors for Placental Abruption
  • Existing Conditions: Previous abruption carries high risk for recurrence.
  • Abdominal Trauma: Physical injury can cause detachment.
  • Smoking and Drug Use: Similar to previa, substances like cocaine and meth can increase risk.
  • Chronic Conditions: Hypertension and conditions like preeclampsia raise risk levels.
  • Premature Rupture of Membranes (PROM): Loss of amniotic fluid increases pressure on the placenta, leading to abruption.
Classic Signs and Symptoms of Abruption
  • Presenting Symptoms:
    • Severe, painful vaginal bleeding during the third trimester.
    • Abdominal and/or back pain can be significant.
    • Uterine contractions may be present, either as a reaction to the trauma or if labor is impending.
  • Hemorrhagic Shock:
    • Severe bleeding may not always present visibly; signs of shock need to be assessed (cool clammy skin, quickening heart rate).
Treatment Approaches for Both Conditions
  • General Management:
    • Shock Treatment: Maintain airway, breathing, and circulation as a priority.
    • Oxygen Therapy: Administer oxygen to all patients suspected of having previa or abruption, regardless of symptoms.
  • Urge for Advanced Life Support (ALS):
    • Rapid transport to ALS or emergency department is crucial.