Trauma: Trauma in Pregnancy

Pregnancy

General Considerations

  • Always Mother Before Baby
  • Most Common Cause of Death: Intimate Partner Violence
  • Blunt Trauma
    • Fetal Injury After Blunt Trauma is Rare (< 1%)
    • Most Common Cause of Fetal Death in Blunt Trauma: Maternal Death
  • Penetrating Trauma
    • High Fetal Death Rate – GSW 71% & Stabs 42%
    • Gravid Uterus Provides Protection for Mother with Decreased Mortality

Fetal Maturity

  • Fundal Height (Umbilicus = 20 cm = 20 Weeks)
  • Signs of Maturity:
    • Lecithin:Sphingomyelin (LS) Ratio > 2:1
    • Phosphatidylcholine in Amniotic Fluid

Radiology

  • Do Not Delay or Withhold if Indicated
  • No Increased Risk of Fetal Defects/Loss if < 5 Rad
  • Fetus Exposed to About 30% of Maternal Radiation Dose
  • Approximate Fetal Dose:
    • CXR: < 0.001 Rad
    • Abdominal XR: 0.1 Rad
    • Head CT: < 0.05 Rad
    • Chest CT: < 0.1 Rad
    • Abdominal CT: 2.6 Rad
  • Timing:
    • Most Vulnerable During Organogenesis (Weeks 2-8)
    • Generally Safe Past 20 Weeks
  • FAST US
    • Any Amount of Free Fluid is Considered Positive
    • Physiologic Free Fluid is Small (7-21 cc) & Not Large Enough to Be Seen on FAST

Managements

  • Cardiotrophic Fetal Monitoring for ≥ 6 Hours if Over 20 Weeks Gestation
  • Give Supplemental O2 in All Pregnant Patients Regardless of SaO2
    • Physiologic Respiratory Alkalosis with Concern for Hypoxia
  • Give Rh Immunoglobulin to All Rh-Negative Patients
    • Give within 72 Hours of Injury
    • Should Also Be Given within 72 Hours of Delivery
  • Aortocaval Compression Syndrome (Supine Hypotensive Syndrome)
    • Gravid Uterus Compresses Aorta & IVC When Laying Supine
    • Presentation: Maternal Hypotension
    • Tx: Roll to Left Side (Improves Venous Return)
  • If Unable to Adequately Expose Injury Due to Enlarged Uterus: Cesarean Section

Aortocaval Compression Syndrome 1

Left Lateral Tilt – Relieves Compression Off IVC 1

Specific Trauma

  • Placental Abruption
    • Separation of Placenta from Uterus
    • Causes:
      • Uteroplacental Ischemia from Shock – Most Common
      • Mechanical Force
    • Presentation: Abdominal Pain, Vaginal Bleeding, Shock or DIC
    • Kleihauer-Betke Test: Detects Occult Placental Hemorrhage
  • Uterine Rupture
    • Most Common Site: Posterior Fundus
    • Most Common Risk Factor: Previous C-Section

Placental Abruption 2

Uterine Rupture 3

Perimortem Cesarean Section

  • Definition: C-Section Delivery After Maternal Death
  • Baby Must Be > 24 Weeks
  • Arrest Timing:
    • Best if < 4 Minutes of Arrest
    • Contraindicated > 20 Minutes

References

  1. Queensland Clinical Guidelines. Trauma in pregnancy clinical guideline education presentation E19.31-1-V2-R24. Queensland Health. 2019. (License: CC BY-NC-ND-4.0)
  2. Blaus B. Wikimedia Commons. (License: CC BY-3.0)
  3. Khcnrc01. Wikimedia Commons. (License: CC BY-SA-4.0)