Trauma-- OB =========== Ultrasound: þ Uterine Rupture: - rare except in very late pregnancy - severe abdominal pain, loss of fetal activity and heart tones - uterus may be contracted and normal contour lost, fetal parts palpable - surgical exploration indicated - fetal demise usual but maternal survival normal þ Abruption: - classic presentation: dark red painful bleeding (placenta praevia classically is painless bright red bleeding) - firm tender uterus - 80% have external bleeding (from the os) - trauma an uncommon cause of abruption; but, abruption more common than rupture after trauma - retroplacental bleeding releases large amounts of thromboplastin into circulation and causes DIC; 20-38% of abruption cases have coagulation defects - Maternal morbidity rarely later than 1-2% but fetal mortality about 35% - difficult to detect on ultrasound (however, ultrasound is 93-98% sensitive for placenta previa) - if fetus alive and viable but dates (via ultrasound), 60% will need stat C-section; if 24-32 weeks, may be allowed to continue þ Position - place pregnant patients on the left side if spine cleared - x-ray with impunity, but shield þ Fetal Mortality - 80% of fetuses die when is maternal shock þ Penetrating trauma above the uterus - increased chance of bowel penetration due to compression above uterus - all gunshot wounds require exploration, but stab wounds can be managed as for nonpregnant patient - DPL (or US) preferred over CT due to high amount of radiation þ Penetrating injuries to uterus - when uterus injured, injury to other organs in 25% of cases - viable fetus in distress after penetrating trauma is indication for immediate C-section - in nonviable situations, some recommend expectant management; only if: - entry level below fundus - bullet clearly visible on x-ray - vital signs stable - DPL negative - no blood in urine or GI tract þ Fetomaternal Hemorrhage and Rh Sensitization - there is no good evidence that RhoGAM is needed prior to 12 weeks - standard texbooks (e.g., The Clinical Practice of Emergency Medicine Lippincott 1991) recommend administering 50 mcg under 12 weeks' gestation and 300 mcg afterwards. - OBs at Mercy say full 300 mcg for full miscarriage even before 12 weeks. - occurs to some degree in any pregnancy - much increased in trauma; more than 100cc in severe cases - most Rh- pregnant women carrying Rh+ fetuses. - as little as 1cc of fetal blood into maternal blood can cause sensitization - sensitization causes maternal antibody IgG response that crosses placenta and kills fetal RBCs - Kleihauer-Betke (KB) test - estimates extent of fetomaternal hemorrhage based on mathematical equation - based on fact that adult hemoglobin is more easily eluted through the cell membranes than fetal - maternal blood fixed on slide and treated to remove maternal hemoglobin; fetal cells then counted - can pick up 5cc of fetomaternal hemorrhage; smaller but significant amounts not detected. (1 fetal cell per 1000 maternal cells = 5 mL fetal bleed) - all pregnant Rh- women with and significant abdominal trauma should receive Rhogam; if in doubt, give it. - 300 micrograms of Rhogam will neutralize 15-30cc fetal blood - Additional doses of Rhogam needed in 1% of all trauma cases and 3% of all major cases involving Rh- women. - Additional doses not needed in pregnancy less than 16 weeks gestation, since fetal blood volume less than 30 cc. - Some experts recommend repeating KB test in 24-36 hours to detect delayed leakage. - Rhogam, single dose, is good for 6-7 weeks--if bleeding again within 6-7 weeks, no need for additional dose. Cahill et all Minot truama in pregnance Ma J Ob and Gyn 2008: Very broad definition of minor trauma (some VERY minor); poor followup. + KB, fibrinogen < 200, direct abdominal trauma combined: