DESCRIPTION

• Hemorrhage at the decidual–placental interface leading to complete or partial separation of the normally implanted placenta before delivery of the fetus
• Incidence/prevalence:
  • ~1% of all pregnancies
  • 30% of bleeding episodes in the 2nd half of pregnancy
  • 15% of all fetal deaths
  • Neonatal death in 10–30% of cases
  • 6% of all maternal mortality
• Synonym(s): Abruptio placentae, accidental hemorrhage (in UK)

ETIOLOGY

• Primary cause unknown
• Vascular injury with dissection of blood into the decidua basalis or mechanical shearing between the placenta and uterus leading to bleeding and clot formation
• More severe cases lead to:
  • Development of disseminated intravascular coagulation (DIC)
  • Maternal–fetal compromise
• Research suggests that the majority of abruptions are due to chronic processes:
  • Inflammatory changes in the placenta
  • Manifestation of ischemic placental disease
• Acute abruption can occur due to:
  • Trauma
  • Rapid uterine decompression
  • Placenta implantation over a uterine anomaly or fibroid
• Multiple known risk factors:
  • Previous abruption (10–20% recurrence risk)
  • Maternal hypertension (> 140/90) and preeclampsia
  • Increased parity and maternal age
  • Multiple gestation
  • Fibroids or other uterine/placental abnormalities
  • Tobacco use
  • Cocaine abuse
  • Trauma
  • Premature rupture of membranes, particularly if associated with chorioamnionitis or oligohydramnios
  • Rapid uterine decompression:
    • Polyhydramnios with membrane rupture
    • Rapid delivery of 1st twin
  • Elevated 2nd trimester maternal serum α-fetoprotein
  • Thrombophilias
  • Maternal race:
    • More common among African American and Caucasian women
    • Incidence increasing more rapidly among African American women

[Outline]

• DESCRIPTION
• ETIOLOGY

SIGNS AND SYMPTOMS

History

• 20+ wk of pregnancy
• Vaginal bleeding (> 80%, usually painful)
• Abdominal or back pain (> 50%)
• Uterine cramps, tenderness, frequent contractions, or tetany
• Nausea, vomiting
• Otherwise unexplained preterm labor
• History of recent trauma should be elicited
• Recent drug use, particularly cocaine or other sympathomimetics
• Prior abruption or other risk factors
• Estimated gestational age
• Prenatal care history

Physical Exam

• Signs of hypotensive shock may be present
• Uterine tenderness frequently present
• Vaginal bleeding (absent in 20–25%)
• Petechiae, bleeding, and other signs of DIC
• Decreased fetal heart tones and movement
• Fetal bradycardia or nonreassuring fetal heart rate tracings

ALERT

ESSENTIAL WORKUP

• Large-bore IV access
• Blood type, Rh, and cross-match
• Rapid hemoglobin determination
• Determine fetal heart tones by Doppler
• Fetal monitoring to detect signs of early fetal distress
• Uterine tocographic monitoring

DIAGNOSIS TESTS & INTERPRETATION

Diagnosis is primarily clinical, supportive tests include

Lab

• Blood type and Rh
• CBC
• PT/PTT
• Fibrinogen levels (normally 450 in latter half of pregnancy) and fibrin split products
• Fibrinogen < 200 mg/dL and platelets < 100,000/µL highly suggestive of abruption
• Kleihauer–Betke if mother Rh-negative (significant fetal-to-maternal hemorrhage more likely in traumatic abruption)

Imaging

• US demonstrates evidence of abruption in only 50% of cases (false-negative common)
• MRI sensitive but impractical
• If abdomen/pelvis CT scan done as part of maternal trauma evaluation, evidence of abruption may be visible (must ask the radiologist to evaluate specifically)

DIFFERENTIAL DIAGNOSIS

• Placenta previa
• Bleeding during labor
• Vaginal or cervical lacerations
• Uterine rupture
• Preterm labor
• Ovarian torsion
• Pyelonephritis
• Cholelithiasis/cholecystitis
• Appendicitis
• Other blunt intra-abdominal or pelvic injuries

[Outline]

• SIGNS AND SYMPTOMS
• ESSENTIAL WORKUP
• DIAGNOSIS TESTS & INTERPRETATION
• DIFFERENTIAL DIAGNOSIS

PRE-HOSPITAL

• Patients with abruption may be in shock and need full resuscitative measures
• Transport in the left lateral recumbent position

INITIAL STABILIZATION/THERAPY

• Airway, breathing, circulation (ABCs), oxygen
• Cardiac monitor
• Placement of large-bore IVs
• IV crystalloid resuscitation

ED TREATMENT/PROCEDURES

• Maternal cardiac and tocographic monitoring
• Continuous fetal monitoring
• Transfuse PRBCs, fresh frozen plasma (FFP), cryoprecipitate, and platelets as indicated (may require massive transfusion protocol)
• Immediate OB/GYN consultation
• Foley catheter for close monitoring of urine output
• Tocolysis is generally contraindicated
• If abruption is suspected in the setting of trauma, maternal stabilization is of primary importance:
  • All indicated radiographs should be performed as needed

MEDICATION

First Line

• Rh-immunoglobulin in Rh-negative women:
  • 300 µg IM in women at ≥12 wk gestation
  • Higher doses if indicated by results of Kleihauer–Betke test
• Blood products as indicated

Second Line

Consider with obstetrician recommendation:

• Magnesium sulfate if tocolysis is indicated
• Steroids for fetal lung maturation if gestational age between 24 and 34 wk

[Outline]

• PRE-HOSPITAL
• INITIAL STABILIZATION/THERAPY
• ED TREATMENT/PROCEDURES
• MEDICATION

DISPOSITION

Admission Criteria

• Patients with placental abruption must be admitted for maternal and fetal monitoring
• Admit to ICU if DIC, amniotic fluid embolism, or significant hemorrhage (known or suspected)
• Victims of multiple trauma with abruption should be admitted and managed in accordance with trauma protocols
• Transportation to higher trauma or obstetric level of care is appropriate if the patient is stable for transfer or appropriate care unavailable at existing facility

Discharge Criteria

• Trauma patients with no evidence of abruption or other significant injury may be discharged after 4–6 hr of normal maternal and fetal monitoring
• Discharge instructions include pelvic rest, no intercourse, no heavy lifting, no prolonged standing
• Discharge decision should be made in consultation with OB/GYN and include close follow-up

Issues for Referral

All cases of confirmed or suspected abruption require immediate obstetric consultation

• Primarily a clinical diagnosis: No single test reliably confirms or rules out placental abruption
• Hypotension typically occurs late in the course of hypovolemic shock in pregnancy
• Anticipate a consumptive coagulopathy and consider the need for blood products early in presentation
• Abruption may be associated with severe preeclampsia, causing a hypovolemic patient to be normotensive:
  • Maintain a high index of suspicion for preeclampsia in patients with severe abruption and no obvious cause

ICD9

• 641.20 Premature separation of placenta, unspecified as to episode of care or not applicable
• 641.21 Premature separation of placenta, delivered, with or without mention of antepartum condition
• 641.23 Premature separation of placenta, antepartum condition or complication

ICD10

• O45.90 Premature separation of placenta, unsp, unsp trimester
• O45.91 Premature separation of placenta, unsp, first trimester
• O45.92 Premature separation of placenta, unsp, second trimester

[Outline]

• ICD9
• ICD10

• Ananth CV, Kinzler WL. Placental abruption: Clinical features and diagnosis. In: UpToDate. Rose BD, ed. Waltham, MA: UpToDate; 2012.
• Ananth CV, Oyelese Y, Yeo L, et al. Placental abruption in the United States, 1979 through 2001: Temporal trends and potential determinants. Am J Obstet Gynecol. 2005;192:191–198.
• Elasser DA, Ananth CV, Prasad V, et al. Diagnosis of placental abruption: Relationship between clinical and histopathological findings. Eur J Obstet Gynecol Repro Biol. 2010;148:125–130.
• Kopelman TR, Berardoni NE, Manriquez M, et al. The ability of computed tomography to diagnose placental abruption in the trauma patient. J Trauma Acute Care Surg. 2013;74:236–241.
• Oyelese Y, Ananth CV. Placental abruption: Management. In: UpToDate. Rose BD, ed. Waltham, MA: UpToDate; 2012.

See Also (Topic, Algorithm, Electronic Media Element)

• Placenta Previa
• Trauma in Pregnancy
• Vaginal Bleeding in Pregnancy
• DIC

Rebecah W. Schwartz