Trauma in pregnancy

Background

  • Concern for trauma, premature labor, and abruption
  • Viable = >23-24wk (~fundus above umbilicus)
  • nl FHR = 110-160 beats/min
  • The leading cause of death in women during their reproductive years
  • The leading non-obstetric cause of death and disability in pregnant women
  • Trauma or accidental injury complicates up to 7% of all pregnancies
  • For maternal vitals see Maternal Vitals and Labs in Pregnancy

Risk Factors for Severity (ATLS)

  • Maternal heart rate > 100
  • Injury Severity Score > 9
  • Evidence of placental abruption
  • Fetal heart rate > 160 or <120
  • Ejection during a motor vehicle crash
  • Motorcycle or pedestrian collisions

Assessment

  • Airway
    • Prepare for potentially difficult airway
      • Increased soft tissue edema, breast enlargement, weight gain
    • Pregnant women at increased risk of aspiration due to delayed gastric emptying
    • Failed intubations 8 times more likely in pregnant trauma patients
  • Breathing
    • Increased basal O2 requirement
    • Fetus is highly sensitive to maternal hypoxia
      • Keep maternal SpO2 >95%
    • Some recommend placement of thoracostomy tube 1-2 intercostal spaces higher than usual, when indicated[1]
  • Circulation
    • Fluid and blood product resuscitation should proceed according to ATLS
    • Placenta is highly responsive to vasopressors and can result in decreased placental perfusion
    • Compression of IVC by gravid uterus can decreased CO by 30%
      • If must be kept supine, allow patient to lay in left lateral position
      • May also manually displace uterus to the left if patient must be kept on backboard
    • Fetal risks from defibrillation of mother are small

Complications

  • Uterine rupture
    • more common with direct abdominal trauma in second half of pregnancy
    • Occurs in severe MVAs resulting in pelvic fractures, penetrating trauma
    • Signs and Sx
      • maternal shock
      • abdominal distension
      • abnormal uterine contour
      • abnormal fetal lie (oblique or transverse)
      • palpable fetal parts
      • sudden abnormal FHR pattern
      • Ascent of fetal presenting part
  • Placental Abruption
    • Most common cause of fetal demise in blunt trauma
    • US on not sensitive → do not delay treatment for ultrasound if abrpution suspected
    • Signs and Sx
      • abdominal pain
      • uterine tenderness
      • vaginal bleeding (70%, may be absent if retroplacental)
      • Uterine contractions or hypertonicity
      • Signs of fetal distress on toco monitor are often the earliest indicator
        • decelerations, tachycardia, bradycardia, and loss of variability
  • Preterm labor
    • Trauma in pregnancy is associated with 2x higher risk of preterm delivery

Differential Diagnosis

Abdominal Trauma

Evaluation

  • Trauma labs
  • Rh factor
  • Coag studies
  • D-dimer
  • Fibrinogen
  • FAST - sensitivity similar to non-pregnant trauma population
  • Radiographic imaging as directed by ATLS assesment[2]
    • Radiographic imaging should not be delayed or deferred due to concern for fetal radiation exposure in the trauma setting

Treatment & Disposition

Assessment and stabilization of the mother should take first priority

  • Nonviable fetus (<23-24wks)
    • Standard treatment for trauma
      • No obstetric intervention will alter the outcome of a pre-viable fetus
    • Consider RhoGAM 50mcg in Rh negative patients
  • Viable fetus (>23-24wks)
    • Consider RhoGAM 300mcg in Rh negative patients
    • Avoid pressors - compromises blood flow to uterus leading to decreased fetal O2 delivery
    • Fetal monitoring (continuous cardiotocographic monitoring)
      • If no risk factors for fetal loss, minimum 4-6 hours
      • If risk factors for fetal loss/abruption, monitor for 24 hours
        • The duration of cardiotocographic monitoring should be extended to 24 hours if, during the first 4 hours, she develops > 4 contractions per hour, persistent uterine tenderness, a worrisome fetal monitor strip, vaginal bleeding, or rupture of the membranes. [3]
  • Allow patient to roll onto left side to unload uterine compression of IVC → increases venous return to heart
  • In the setting of maternal cardiac arrest, consider Perimortem Cesarean delivery if no ROSC within 4 minutes

Abnormal Monitoring

  • >3 contractions/hr
  • Persistent uterine TTP
  • Worrisome strip
  • Vaginal bleeding
  • PROM
  • Serious maternal injury

Partial abruption with stable mom/fetus and <32wk may have expectant care (with easy access to emergent C-section)

Abruption = risk DIC

  • Frequent uterine activity more predictive of abruption than US
    • >8 contractions/hr for 4hrs - high risk for abruption
    • 3-7 contractions/hr for 4hrs - extend monitoring for 24hrs
    • <3 contractions/hr for 4hrs - safe for discharge

External Links

See Also

References

  1. Tsuei B. Assessment of the pregnant trauma patient. Injury 2006; 37(5)367-373
  2. Edmonton V, Edmonton R, Maslovitz S, et al. Guidelines for the Management of Pregnant Trauma Patient. J Obset Gynaecol Can 2015. 37(6):553-571
  3. Pearlman MD, Tintinalli JE, Lorenz RP. A prospective controlled study of outcome after trauma during pregnancy. Am J Obstet Gynecol. 1990;162:1502–10.