Trauma is most common cause of non-obstetric cause for maternal death (MVC, interpersonal injury, falls). Even minor trauma with no external signs of maternal injury can cause fetal demise.
Pregnancy causes hypervolemia state which can lead to 30% lose of blood volume before mother will show signs of shock.
Quick assessment: after 12 weeks, should be able to palpate uterus past pubic synthesis. After 20 weeks, should be at umbilicus or greater.
Supine Hypotension Syndrome: after 20 weeks, uterus can compress IVC. If backboard, place 30 degree wedge on right hip to move uterus to the left.
Need to do sterile pelvic exam over blind manual exam due to looking for source of bleeding/injury, fluid. Look for premature rupture of membranes – amniotic fluid will fern under drying fluid under microscope exam. Also pH will be 7 whereas vaginal fluid is acidic (pH 5).
Preventative measure: Seatbelt worn with lap band at the lowest possible position under the uterus. Shoulder strap worn between the breasts and on the side of the uterus.
If need to do chest tube, place 1-2 intercostal spaces higher.
Relatively uncommon though high fetal mortality. usually from pelvic fractures.
Hard to assess at bedside. Apt test is qualitative test. Kleihauer-Betke is a lab test looking for >5mL of blood in mother – is quantitive test though will likely not get quickly. Don’t need to worry about it – only from admitting service.
If Rh- mother, just give rhogam, even with minor trauma. Have 72 hour window to give. 50mcg if <12 weeks, 300mcg if >12 weeks.
Most common cause of fetal death in trauma. 1-5% of minor traumas, 40-50% of major trauma. Shear forces applied to placenta base causing placenta separation from uterine wall. Usually abdominal pain with vaginal bleeding in third trimester. Ultrasound may miss rupture/injury (only 24% sensitive). Most sensitive indicator is fetal demise/stress.
Need to have tocomonitoring for at least 4-6 hours. Most pregnancies >20 weeks require monitoring/observation. Partial abruption (<25%) and <32 weeks can be watched with expectant management rather than emergent C-section (though likely will still be admitted for monitoring regardless from the ED).
With moderate trauma, go ahead and apply oxygen.
Focus initially on treating mother first before looking at fetus. Healthy mother leads to healthy fetus. Go ahead and call for fetal monitoring though on arrival. Will need 4-6 hours monitoring if after 22 weeks. Fetal viability usually at 25-26 weeks. Low threshold for admission (tenderness, >3 contractions/hr, late decals, vaginal bleeding, rupture of membranes, serious injury).
Ct scans: no adverse fetal outcomes outside of cancer risk if rad <5 total in pregnancy. CT chest < 1 rad, abd/pelvis 2-5 rads. IV contrast can lead to neonatal hypothyroidism. MRI contrast contraindicated.
Tintinalli, Seventh Edition, Chapter 253: Trauma in Pregnancy
Rosens, Chapter 182: Trauma in Pregnancy