Treatment of the woman with a placental abruption varies depending on her clinical condition, gestational age, and the amount of associated hemorrhage. With a living viable-aged fetus, and with vaginal delivery not imminent, emergency cesarean delivery is chosen by most. In some women, fetal compromise will be evident as shown in Figure 41-19. When evaluating fetal status, sonographic conirmation of fetal heart activity may be necessary because sometimes an electrode applied directly to a dead fetus will provide misleading information by recording the maternal heart rate. If the fetus has died or if it is not considered suiciently mature to live outside the uterus, then
FIGURE 41-19 Placental abruption with fetal compromise. Lower panel: Uterine hypertonus with a baseline pressure of 20 to 25 mm Hg and frequent contractions peaking at approximately 75 mm Hg. Upper panel: The fetal heart rate demonstrates baseline bradycardia with repetitive late decelerations.
vaginal delivery is preferable. In either case, prompt and intensive resuscitation with blood plus crystalloid is begun to replace blood lost from retroplacental and external hemorrhage. hese measures are lifesaving for the mother and hopefully for her fetus. If the diagnosis of abruption is uncertain and the fetus is alive and without evidence of compromise, then close observation may be warranted provided that immediate intervention is available. Colon and coworkers (2016) performed a randomized trial and found no beneits to magnesium sulfate tocolysis given to women with a preterm "nonsevere" abruption at 24 to 34 weeks' gestation.
The compromised fetus is usually best served by cesarean delivery, and the speed of response is an important factor in perinatal outcomes. Kayani and coworkers (2003) studied this relationship in 33 singleton pregnancies with a clinically overt placental abruption and fetal bradycardia. Of the 22 neurologically intact survivors, 15 were delivered within a 20-minute decision-to-delivery interval. However, eight of 11 infants who died or developed cerebral palsy were delivered with intervals > 20 minutes.
A major hazard to cesarean delivery is imposed by clinically signiicant consumptive coagulopathy. Preparations include plans for blood and component replacement and assessment of coagulation-especially fibrinogen levels.
If the fetus has died, then vaginal delivery is usually preferred. As reviewed earlier, hemostasis at the placental implantation site depends primarily on myometrial contraction and not blood coagulability. Thus, after vaginal delivery, uterotonic agents and uterine massage are used to stimulate myometrial contractions. Uterine muscle ibers compress placental site vessels and prompt hemostasis even if coagulation is defective.
In some instances, vaginal delivery may not be preferable, even with a dead fetus. One example is brisk hemorrhage that cannot be successfully managed by vigorous blood replacement. Others are the myriad obstetrical complications that prohibit vaginal delivery in general. hese are listed in Table 30-1 (p. 568).
In some women with extensive placental abruption, labor tends to be rapid because the uterus is usually persistently hypertonic. This can magniy fetal compromise. In some cases, baseline intraamnionic pressures reach 50 mm Hg or higher, and with contractions, pressures may attain levels exceeding 100 mm Hg. Overall, however, irst-and second-stage labor do not appear to be shortened (Downes, 2016).