What is Abruptio Placentae?
Abruptio placentae (placental abruption) is the premature separation of a correctly implanted placenta late in pregnancy.
Pathophysiology
The placenta is implanted in the correct location. For an unknown reason it suddenly begins to separate, causing bleeding. This separation usually occurs after 20 weeks of gestation and is a leading cause of perinatal death, responsible for an estimated 10% to 20% of perinatal mortality (StatPearls).
Risk Factors
- High parity. Multiple prior births raise the risk.
- Short umbilical cord. Can pull the placenta loose, especially with trauma.
- Advanced maternal age. Women over 35 years old are at higher risk.
- Direct trauma. Any abdominal trauma can separate the placenta.
- Chorioamnionitis. Infection of the fetal membranes and fluid that predisposes to premature separation.
Types
Graded by the degree of placental separation.
- Grade 0. No sign of separation; slight separation is diagnosed after birth.
- Grade 1. Minimal separation with vaginal bleeding, no change in fetal vital signs.
- Grade 2. Moderate separation with evident fetal distress; uterus hard and painful on palpation.
- Grade 3. Extreme separation; maternal shock and fetal death are imminent without intervention.
Signs and Symptoms
Catch these before the abruption progresses to a critical stage.
- Sharp, stabbing pain. Pain in the upper uterine fundus as separation begins.
- Heavy bleeding. Follows separation. External bleeding occurs when the placenta separates from the edges; internal bleeding occurs when it separates from the center and blood pools underneath.
- Tense, rigid uterus. The Couvelaire uterus: board-like and hard, often without visible bleeding.
Diagnostic Tests
- Hemoglobin level and fibrinogen level. Performed to rule out disseminated intravascular coagulation.
Medical Management
- Intravenous therapy. Once bleeding starts, the physician orders a large-gauge catheter to replace fluid losses.
- Oxygen inhalation. Delivered by face mask to prevent fetal anoxia.
- Fibrinogen determination. Repeated several times before birth to detect DIC.
Surgical Management
- Cesarean delivery. When birth is imminent, cesarean is the safest route.
- Hysterectomy. If the woman develops DIC, hysterectomy prevents exsanguination.
Nursing Management
Nursing Assessment
- Assess for signs of shock, especially with heavy bleeding.
- Determine whether the bleeding is external or internal.
- Monitor contractions if separation occurs during labor.
- Obtain baseline vital signs.
- Note when the bleeding began, the amount and kind, and any interventions done before admission.
- Assess the quality of pain.
Nursing Diagnosis
- Deficient fluid volume related to bleeding during premature placental separation.
Nursing Interventions
- Position the woman lateral, not supine, to avoid pressure on the vena cava.
- Monitor fetal heart sounds.
- Monitor maternal vital signs for baseline data.
- Avoid vaginal and abdominal examinations to prevent further injury to the placenta.
Evaluation
Maternal vital signs are within normal range, especially blood pressure. Urine output stays above 30mL/hr. Bleeding is absent or minimal. The uterus is no longer tense and rigid. Fetal heart sounds are within normal range.
Frequently Asked Questions
What is the difference between placental abruption and placenta previa?
In abruptio placentae a normally implanted placenta separates from the uterine wall, classically causing painful bleeding and a tense, rigid uterus. In placenta previa the placenta implants over or near the cervix, causing painless bright-red bleeding. The pain pattern and uterine tone are key NCLEX discriminators.
What is a Couvelaire uterus?
A Couvelaire uterus is bleeding into the uterine muscle during a severe abruption, leaving the uterus board-like, rigid, and often without much visible external bleeding. It signals a serious abruption and raises the risk of disseminated intravascular coagulation (DIC).
Why is concealed bleeding so dangerous in abruptio placentae?
When the placenta separates centrally, blood pools behind it instead of escaping through the vagina, so the visible loss badly understates the real loss. The patient can slide into hypovolemic shock while external bleeding still looks minor, which is why vital signs and serial labs matter more than the pad count.
Why are vaginal and abdominal exams avoided?
Manipulation can extend the separation and worsen hemorrhage. The nurse positions the patient on her side to keep pressure off the vena cava, monitors fetal heart tones and maternal vital signs, and defers exams to the provider.
What lab tests are monitored and why?
Hemoglobin tracks blood loss, and fibrinogen and coagulation studies are repeated to catch DIC, a known complication of abruption. Falling fibrinogen is an early warning that clotting factors are being consumed.
What are the main risk factors for placental abruption?
Prior abruption, hypertension, abdominal trauma, advanced maternal age, high parity, chorioamnionitis, and cocaine or tobacco use all raise the risk (StatPearls). A history of abruption is one of the strongest predictors.