II. Epidemiology

  1. Unintentional Trauma occurs in 7% of pregnancies
  2. Obstetric Trauma is responsible for 20% of maternal mortality (esp. MVA)
  3. Fetal mortality approaches 60% in maternal Trauma

III. Precautions: Pearls

  1. Assume pregnancy in all females of reproductive age
  2. Seemingly minor injuries can have major maternal and fetal complications
    1. Minor Trauma is responsible for 60-70% of fetal losses
    2. Fetal Monitoring recommendations are the same for both minor and major Trauma
  3. Hemorrhagic Shock can be masked until cardiovascular collapse and Cardiac Arrest
    1. Pregnant women have 20% Cardiac Output reserve allocated to uterine blood flow
    2. Blood is shunted from the Uterus and fetus in obstetric Trauma with Hemorrhage
  4. Respiratory depression, Hypoxia and airway risks
    1. Higher CNS sensitivity to Opioids in pregnancy (reduced Opioid dose needed)
    2. Adequate analgesia results in less risk of Preterm Labor (lower Catecholamine surge)
    3. Higher airway compromise and Hypoxia risk in pregnancy (pharynx/Larynx edema, less functional reserve)
  5. Hypotension and uteroplacental insufficiency risks
    1. Aortocaval compression with reduced fetal blood flow when supine, esp. >20 weeks (position in decubitus)
    2. Hypotension (esp. if >25-30% drop in Blood Pressure)
    3. Hyperventilation and Metabolic Alkalosis

IV. Pathophysiology

  1. Pregnancy related physiologic changes
    1. Blood Volume increases 30-50% in pregnancy
    2. Oxygen consumption increases 25% in pregnancy
      1. Respiratory Rate increases 40-50% in pregnancy
  2. Pregnancy related anatomic changes (especially third trimester)
    1. Diaphragm elevates
    2. Delayed Gastric Emptying
    3. Uterine growth (especially third trimester)
      1. Uterus expands outside the protective Bony Pelvis
      2. Uterine wall thins as pregnancy progresses
      3. Placenta is susceptible to external forces that may provoke Placental Abruption

V. Causes

  1. Motor vehicle accident (42-48%)
  2. Falls (25-34%)
    1. Most common in third trimester
  3. Direct blunt Abdominal Trauma (18%)
  4. Intimate Partner Violence (17%)
    1. Gunshot Wounds
    2. Stabbings
  5. Suicide (3%)

VI. History

  1. See Trauma History
  2. Gestational age
  3. Multiple Gestation
  4. Rh Status
  5. Mechanism of injury
    1. Possible Intimate Partner Violence?
    2. Seat Belt use (in MVA)
      1. Positioning of Seat Belt?
      2. See Seat Belt Use in Pregnancy for proper positioning
  6. Symptoms
    1. Vaginal Bleeding
    2. Vaginal fluid discharge
    3. Uterine contractions
    4. Fetal movement
    5. Abdominal Pain, Pelvic Pain or Low Back Pain

VII. Classification

  1. Minor Trauma (90% of cases)
  2. Major Trauma
    1. Rapid compression, deceleration or shearing forces (e.g. motor vehicle accident)
    2. Abdominal Injury
    3. Pain reported
    4. Vaginal Bleeding
    5. Amniotic fluid loss
    6. Decreased fetal movement

VIII. Exam: Indications for Advanced Cardiac Life Support (ACLS)

  1. Cardiac Arrest
  2. Unresponsive
  3. Respiratory arrest or airway compromise
  4. Blood Pressure <80/40 mmHg
  5. Heart Rate <50 or >140 beats/min
  6. Viable fetus with Fetal Heart Rate <110 or >160 beats/min

IX. Exam: Primary Survey

  1. See Primary Survey
  2. Airway
    1. Gastric aspiration increased risk in pregnancy
    2. Intubation
      1. Anticipate a difficult airway in all pregnant Trauma patients
      2. Airway managament failure rate is 8 fold higher in pregnancy than the general population
      3. Rapid Sequence Intubation (RSI) and Sedation agents are described below
      4. Endotracheal Intubation in pregnancy is difficult (1 failure in 224 patients)
        1. Regardless of ideal anesthesia conditions
        2. Quinn (2013) Br J Anaesth 110(1): 74-80 [PubMed]
    3. Endotracheal Tube size
      1. Airway edema in pregnancy
      2. Use smaller Endotracheal Tube (6.5 to 7.0 mm internal diameter)
  3. Breathing
    1. Oxygenation
      1. Rapid oxygen desaturation occurs with apnea in pregnancy
        1. Oxygen consumption increases by 20% in pregnancy (due to maternal and fetal requirements)
      2. Apply Supplemental Oxygen early as indicated
        1. Maintain maternal Oxygen Saturation >95% to ensure adequate fetal oxygenation
      3. Intubation Preoxygenation and Apneic Oxygenation during intubation
        1. Decreases risk of significant oxygen desaturation during intubation attempt
    2. Chest Tubes
      1. Diaphragm is higher in pregnancy (especially in third trimester)
      2. Place 1-2 interspaces higher (4th to 5th intercostal space) in later pregnancy to stay in the pleural space
      3. Consider using chest Ultrasound to define the pleural space and level of diaphragm during exhalation
  4. Circulation
    1. Cardiovascular physiology in pregnancy
      1. Cardiac ouput increases by 40% by 10 weeks gestation
        1. RBC volume increases 20-30%
        2. Plasma volume increases 50%
      2. Relative Tachycardia and Hypotension are typical by the second trimester of pregnancy
        1. Blood Pressure decreases by 10-15 mmHg by the second trimester
        2. Heart Rate decreases by 5-15 beats per minute by the second trimester
      3. Pregnant women can lose 10-20% of Blood Volume before it is reflected by Tachycardia and Hypotension
        1. Decreased uterine blood flow is an early compensatory Mechanism in maternal Hemorrhage
        2. Fetal Distress is an early indicator of maternal vascular collapse
    2. Hypotension and Tachycardia
      1. Obtain early 2 large bore IVs in seriously injured pregnant women
      2. Assume Tachycardia and Hypotension are due to Hemorrhage in Obstetrical Trauma
      3. Hypotension and Tachycardia are ominous, late changes in Obstetrical Trauma
      4. Fetal Heart Rate monitoring is a maternal Vital Sign as an earlier indicator of obstetrical Hemorrhage
    3. Supine Hypotension syndrome
      1. Uterine compression on aorta and inferior vena cava while supine
        1. Leads to 30% decreased Cardiac Output after 20 weeks gestation
        2. Supine position results in Hypotension
      2. Prevention
        1. Position patient in left lateral decubitus preferred if spine is cleared or
        2. Tilt Backboard 30 degrees leftward or
        3. Manually displace Uterus to the left
  5. Disability
    1. Brief Neurologic Exam including Glasgow Coma Scale (GCS) as with non-pregnant secondary survey
    2. Differential diagnosis for Altered Level of Consciousness in pregnancy includes Eclampsia
  6. Exposure
    1. Complete exposure as with non-pregnant secondary survey
    2. Define injuries related to both nonintentional Trauma and Intimate Partner Violence

X. Exam: Secondary Survey

  1. See Secondary Survey
  2. Pregnancy specific focus areas
    1. Vaginal exam (defer if suspected placental previa)
      1. Blood or amniotic fluid
      2. Vaginal Lacerations
    2. Uterine exam
      1. Pelvic exam
      2. Tocometry for contractions
      3. Fetal Monitoring for Fetal Distress
        1. Maternal evaluation takes priority over fetus
        2. Fetal Heart Tones act as the canary in the coal mine
          1. Detects significant uterine Trauma or hemodynamic instability
  3. Abdominal Injury risk increases
    1. Uterine injury (e.g. Placental Abruption)
      1. Uterus exposed out of pelvic brim by 8-12 weeks and is subcostal by 36 weeks
      2. Placenta susceptible to shearing forces
        1. Rapid acceleration or deceleration
      3. Highest risk in third trimester
        1. Thin-walled Uterus
        2. Decreased amniotic fluid
        3. Engaged fetal head inside Pelvis
    2. Bladder injury
    3. Stomach often full due to delayed emptying
      1. Aspiration risk in Trauma and surgery
      2. Insert a Nasogastric Tube in semiconscious or unconscious pregnant women
  4. Pelvic Fractures associated with high morbidity
    1. Bladder injury
    2. Injury to Urethra
    3. Retroperitoneal bleeding
    4. Fetal Skull Fracture (42% mortality rate)

XI. Labs

  1. See Diagnostic Testing in Trauma
  2. Initial
    1. Complete Blood Count (normal findings in pregnancy)
      1. Leukocytosis
      2. Relative Anemia (compare with prior labs)
    2. Blood Type and Rh Factor
  3. Additional studies in major Trauma
    1. Coagulation Factors (INR, PTT and Fibrinogen)
    2. Comprehensive metabolic panel (electrolytes, Renal Function tests, Liver Function Tests)
    3. Arterial Blood Gas
      1. Expect suppressed pCO2 as normal (pCO2 40 mmHg may signal impending respiratory failure)
      2. pCO2 is suppressed more in pregnancy at baseline
    4. Kleihauer-Betke Test
      1. Variable recommendations regarding utility
      2. Useful beyond dosing RhoGAM in Rh negative patients
        1. Detects fetomaternal transfusion and acts as a marker of fetomaternal Hemorrhage
      3. RhoGAM is typically given in standard dosing to all women who are Rh negative
        1. Exceptions are described below

XII. Diagnostics

  1. See EKG Changes During Pregnancy
  2. Fetal Monitoring (4 hours minimum)
    1. Continuous Tocometry
      1. Abnormal Tocometry (8 contractions/hour for 4 hours) has a 100% Test Sensitivity for Placental Abruption
      2. Observe for 24 hours if 3-7 contractions per hour
    2. Fetal Heart Rate monitoring
      1. Continuous Electronic Fetal Monitoring for >20-24 weeks gestation (and intermittent monitoring if earlier)
      2. Monitor as a maternal Vital Sign that is an early detector of impending vascular compromise

XIII. Imaging

  1. See Radiation Exposure in Pregnancy
  2. Precautions
    1. Maternal safety is the first consideration in Obstetrical Trauma
      1. Do not delay ionizing radiation imaging (XRay or CT) in maternal hemodynamic instability
      2. The risk of missing serious Traumatic Injury in hemodynamic instability far outweighs Fetal Radiation Exposure
    2. Radiologist Consultation
      1. Consider Consultation with radiologist when considering multiple ionizing radiation studies in pregnancy
      2. However, do not delay critical imaging in the unstable patient
    3. Nonionizing radiation imaging (Ultrasound or MRI) is preferred in pregnancy if no delays
      1. However Gadolinium contrast is not recommended in pregnancy (risk of nephrogenic systemic fibrosis)
  3. Standard XRays
    1. Complete critical XRays as in non-pregnant patients
      1. Maternal evaluation takes priority (but be selective where possible)
    2. Radiation exposure
      1. Plain film XRay risk is low
      2. Risk of fetal adverse effects low if rads <5
        1. Even a pan-scan has <5 rads
        2. Shield Uterus as much as possible
      3. Radiation exposure risk is even lower if Gestational age >15 weeks
    3. Chest XRay (normal findings in pregnancy)
      1. Decreased inspiration
      2. Wide mediastinum
  4. FAST Exam
    1. Unchanged in pregnancy (but can capture Fetal Heart Tones on pelvic view)
    2. Best Test Sensitivity for Hemorrhage in first trimester of pregnancy
    3. Decreased Test Sensitivity for Hemorrhage on FAST Exam after the first trimester
  5. Obstetric Ultrasound
    1. See Obstetric Ultrasound
    2. Indications
      1. Distinguishes maternal and Fetal Heart Rates
      2. Confirms live fetus
      3. Identifies placental location
      4. Determines amniotic fluid index
      5. Establishes Gestational age (for viability >24 weeks gestation)
    3. Emergency physicians can accurately and rapidly estimate Gestational age by Bedside Ultrasound
      1. See Fetal Biparietal diameter
      2. See Fetal Femur Length
      3. Shah (2010) Am J Emerg Med 28(7): 834-8 [PubMed]
    4. Ultrasound misses most Placental Abruptions
      1. Tests sensitivity for abruption: 20-50% (NPV 53%)
      2. However, Ultrasound is highly specific for abruption (88% PPV, 96% Test Specificity)
      3. Glantz (2002) Ultrasound Med 21(8): 837-40 [PubMed]
    5. Precautions
      1. Avoid doppler mode to measure Fetal Heart Rate (use M-Mode instead)
      2. Doppler mode (and especially power doppler mode) is associated with high fetal energy exposures

XIV. Management: High risk indicators for 24 hours intense monitoring

  1. Vaginal Bleeding
  2. Spontaneous Rupture of Membranes
  3. Fetal heart tone abnormality (Non-reassuring Fetal Heart Tracing)
  4. Uterine contractions for >4 hours
    1. Consider Placental Abruption (8/hour for 4 hours)
      1. Pearlman (1990) Am J Obstet Gynecol 162:1502-10 [PubMed]
    2. Continued monitoring for 24 hours is recommended for 6 or more contractions per hour
    3. Occasional contractions are common after Trauma
      1. Usually <3-7 contractions per hour
      2. Contractions usually resolve within 4 hours
      3. Avoid Tocolytics (delays abruption diagnosis)
  5. Uterine tenderness
  6. Abdominal Pain
  7. Positive Kleihauer-Betke test
  8. Serum Fibrinogen <200 mg/dl
  9. High risk injury
    1. Pedestrian struck by motor vehicle
    2. High speed motor vehicle accident

XV. Management: Maternal Stabilization (Primary Survey)

  1. See ABC Management
  2. See Trauma Primary Survey
  3. Consult obstetrics early for viable fetus >23 weeks gestation
    1. Emergent consult for contractions, Placental Abruption, Uterine Rupture
  4. Maternal health is first priority
  5. See Primary Survey as above
  6. Oxygen supplementation to maintain Oxygen Saturation >95%
  7. Fetal Heart Tones are a maternal Vital Sign and an early predictor of maternal vascular collapse
  8. Decrease uterine compression of Great Vessels (see above)
    1. Left lateral decubitus position or displace Uterus manually to side
  9. Intravenous Fluids (Lactated Ringers or Normal Saline)
    1. Obtain 2 large bore IVs early
    2. See Hypotension and Tachycardia concerns as above
    3. Consider early pRBC transfusion with Rh negative blood (until typed) if significant Hemorrhage suspected
    4. Volume Resuscitation is far preferred over Vasopressors (less uteroplacental insufficiency)
    5. Consider Tranexamic Acid for bleeding Obstetrical Trauma presenting in the first 3 hours
      1. Shakur (2010) Lancet 376(9734):23-32 [PubMed]

XVI. Management: Rapid Sequence Induction (RSI) and Post-Intubation Sedation

  1. Rapid Sequence Induction (RSI)
    1. Etomidate
    2. Succinylcholine
  2. Post-Intubation Sedation
    1. Propofol
      1. Preferred initial agent in hemodynamically stable patients
      2. Dose: 20-40 mg bolus, then 20-40 mcg/kg/min infusion
    2. Ketamine
      1. Reserve for patients with significant Hypotension
      2. Dose: 10-80 mcg/kg/min infusion
    3. Dexmedetomidine
      1. Safe agent, but use requires experience in dosing (often used in postpartum ecclampsia)
      2. Dose: 1 mcg/kg bolus over 10-20 min, then 0.2 to 1.4 mcg/kg/hour infusion
    4. Fentanyl
      1. Consider as adjunct
      2. Dose: 1 to 1.5 mcg/kg bolus followed by 1 to 1.5 mcg/kg/h infusion
    5. Other agents
      1. Midazolam
        1. Other agents are preferred
  3. References
    1. Rebel EM: Post Intubation Sedation for Pregnant Patients
      1. http://rebelem.com/post-intubation-sedation-for-pregnant-patients/

XVII. Management: Maternal Secondary survey

  1. See Trauma Secondary Survey
  2. Treat non-obstetrical injuries as needed
  3. Administer RhoGAM if Rh negative
    1. Kleihauer-Betke test may be useful as a marker of fetomaternal Hemorrhage (regardless of Rh status)
    2. Administer one full dose (RhoGAM 300 mcg) in all Rh negative patients with Obstetrical Trauma
      1. Administer regardless of Gestational age (some recommend RhoGAM 50 mcg if <12 weeks gestation)
      2. Administer in all but minor extremity Trauma
      3. Rh antigen develops with 0.1 ml of fetal blood in maternal circulation
    3. Consider in suspected large volume fetomaternal Hemorrhage (fetal blood in maternal circulation >30 ml)
      1. May indicate increased RhoGAM dose (discuss with obstetrics)

XVIII. Management: Surgical indications (laparotomy)

  1. Peritonitis
  2. Hemodynamic instability
  3. Burn Injury with burn area >50%
  4. Placental Abruption
    1. High risk for catastrophic complication
    2. Common in Obstetrical Trauma
      1. Occurs in 5% of what is initially considered mild blunt Trauma
      2. Occurs in 50% of severe injury
    3. Hemorrhage may be concealed and only present with Abdominal Pain
      1. Ultrasound or CT Abdomen/Pelvis may be required
      2. Continuous external Fetal Monitoring with Fetal Distress may be the only indicator of Placental Abruption
      3. Abnormal Tocometry (8 contractions/hour for 4 hours) has a 100% Test Sensitivity for Placental Abruption
        1. Pearlman (1990) Am J Obstet Gynecol 162(6): 1502-7 [PubMed]
  5. Uterine Rupture
    1. Uncommon (1% of severe Trauma) but carries a high mortality risk
    2. Fetal mortality approaches 100% and maternal mortality 10%
    3. CT Abdomen has best Test Sensitivity (significantly better than Ultrasound)
  6. Viable fetus and Fetal Distress
    1. Fetal viability in obstetric Trauma is variable per institution, and varies between 20 and 26 weeks
    2. Fetal viability outside of Trauma and with exact dates is typically defined as 23 weeks
    3. Post-mortem C-Section is indicated if Maternal Cardiac Arrest and viable fetus
      1. Decision to proceed with post-mortem ceserean must be made within 4-5 minutes of maternal death
  7. Penetrating Trauma
    1. Uterine penetration with viable fetus and Fetal Distress is an indication for ceserean section
    2. Otherwise, uterine defect is repaired surgically and mother and fetus are observed closely
    3. Gravid Uterus may protect against visceral injury
  8. Maternal Cardiac Arrest
    1. See Perimortem Ceserean Section
    2. Start within 4 minutes of persistent Maternal Cardiac Arrest if fundal height >20 cm
      1. Increases likelihood of ROSC in mother
      2. Decreases aortocaval compression and increasing Preload and Cardiac Output
      3. Improves perinatal outcomes
    3. Concurrent measures
      1. Cardiopulmonary Resuscitation and ACLS protocol
      2. Broad spectrum antibiotics

XIX. Management: Procedural Sedation

  1. See Procedural Sedation
  2. See above for precautions
  3. Preferred sedatives
    1. Methohexital
    2. Other sedatives that are less ideal
      1. Propofol (no Teratogenicity, but limited data)
      2. Midazolam (despite that Benzodiazepines are category D)
        1. Of Benzodiazepines, Midazolam has best safety profile in pregnancy (slowest placental transmission)
  4. Preferred Opioid Analgesics
    1. Fentanyl
    2. Morphine
  5. Preferred local anesthetics
    1. Lidocaine
  6. References
    1. Acker, Koval and Leeper (2017) Crit Dec Emerg Med 31(4): 3-13

XX. Management: Fetus

  1. Document Fetal Heart Tones
    1. No fetal Resuscitation if Fetal Heart Tones absent
      1. Morris (1996) Ann Surg 223:481-91 [PubMed]
    2. Monitor Fetal Heart Tones as a maternal Vital Sign
      1. Acts as an early indicator of maternal blood loss
      2. Fetal Distress precedes maternal Hypotension and Tachycardia
      3. Fetal Distress is a marker of impending maternal vascular collapse
  2. Determine Gestational age (as accurately as possible)
    1. Methods
      1. See obstetrical Ultrasound as above to estimate Gestational age if not known
      2. Fundal height may be used as an initial approximation
        1. Do not use fundal height for making viability decisions
    2. Gestational age >20-24 weeks: See below
    3. Gestational age <20-24 weeks or EFW < 500 grams
      1. No Resuscitation of fetus
  3. Gestational age of >20-24 week gestation
    1. Consider Obstetric Ultrasound (see imaging above)
    2. Consider Betamethasone to improve Fetal Lung Maturity
      1. Indicated for anticipated imminent delivery in Gestational age 24 to 34 weeks
      2. Administer to mother Betamethasone 12 mg IM every 24 hours for 2 doses
    3. Efficacy of monitoring
      1. Abnormal findings poorly predict fetal outcome
        1. Poor sensitivity and Specificity
      2. Normal: Reassuring for home discharge
        1. Negative Predictive Value: 100%
      3. References
        1. Shah (1998) J Trauma 45:83-6 [PubMed]
    4. Protocol: Observe for signs of Placental Abruption
      1. Contraction indications for delivery
        1. Consider if 8 or more per hour for >4 hours
          1. Observe for 24 hours if 3-7 contractions per hour
        2. Avoid Tocolytics after Trauma
          1. May delay Placental Abruption diagnosis
      2. Fetal heart tone indications for delivery
        1. Fetal Bradycardia
        2. Late Decelerations
    5. High risk: 24 hours of monitoring
      1. See high risk indicators above
    6. Low risk: 4 hours (ACOG) to 6 hours (ACS)
      1. Perform electronic Fetal Monitoring and tocometry
      2. See Indications for discharge (below)
      3. Consider delivery for 8 or more contractions per hour (suggestive of Placental Abruption)
        1. Extend monitoring to 24 hours if 3-7 contractions per hour

XXI. Disposition

  1. Major Trauma
    1. Consider transfer to Trauma Center with obstetrics support
    2. Tocometry and continuous Fetal Monitoring for at least 24 hours if indicated
      1. See High risk indicators for 24 hours intense monitoring (as above)
  2. General measures prior to emergency discharge
    1. RhoGAM in nearly all Rh Negative patients
      1. See maternal secondary survey above
      2. Exception may be an isolated injury (e.g. upper extremity) distant from the Abdomen
    2. Tetanus Toxoid
      1. Administer if Tetanus Vaccine has not already been given this pregnancy
      2. Safe in pregnancy
    3. Analgesics
      1. See Analgesic Medications in Pregnancy
    4. Confirm safety in cases of Intimate Partner Violence
      1. Ask patient specifically about Intimate Partner Violence
      2. Assess for safe environment
      3. Assess for Major Depression and Suicidality
    5. Obstetric Ultrasound
      1. Indicated if monitoring was needed beyond >4 hour minimum
  3. Indications for discharge
    1. See High risk indicators for 24 hours intense monitoring (as above)
    2. Contraction resolution
    3. Fetal Heart Tones reassuring
    4. No signs of Rupture of Membranes
    5. No uterine tenderness
    6. No Vaginal Bleeding
  4. Indications to return to labor and delivery
    1. Vaginal Bleeding
    2. Decreased fetal movement
    3. Rupture of Membranes
    4. Persistent uterine contractions
    5. Abdominal Pain

XXII. Prevention

  1. Intimate Partner Violence (IPV)
    1. See Intimate Partner Violence
    2. Universal screening for IPV is recommended in pregnancy (abuse often increases in pregnancy)
    3. Abdomen is the most common target for assaults
  2. Motor Vehicle Accident related injuries
    1. MVAs affect 2% of pregnant women with a resulting 368 maternal deaths per year in the U.S.
    2. Air bags should not be disabled
    3. Pregnant women should use Seat Belts (positioned appropriately)
      1. See Seat Belt Use in Pregnancy for positioning

XXIII. References

  1. Murphy (2000) ALSO, F:1-20
  2. Brown in Majoewsky (2012) EM:Rap 13(1): 11
  3. Hirashima (2014) Crit Dec Emerg Med 28(6):12-18
  4. Baerga-Varela (2000) Mayo Clin Proc 75:1243-8 [PubMed]
  5. Grossman (2004) Am Fam Physician 70:1303-13 [PubMed]
  6. Murphy (2014) Am Fam Physician 90(10): 717-22 [PubMed]

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Ontology: Traumatic injury during pregnancy (C1959898)

Concepts Injury or Poisoning (T037)
SnomedCT 426997005
English Traumatic injury during pregnancy (disorder), Traumatic injury during pregnancy
Spanish lesión traumática durante el embarazo, lesión traumática durante el embarazo (trastorno)