Pregnancy

The leading nonobstetrical cause of maternal death in pregnancy is trauma [1]. Trauma impacts 1/12 of all pregnancies, and almost 1% of all trauma admissions are pregnant women [2]. The most common type of injury is blunt trauma, accounting for over 2/3 of the reported trauma [1]. Common mechanisms include motor vehicle collisions (MVCs), falls, and assault, with MVC being the most common and the most deadly with a mortality rate of 13.7% [3]. Studies examining mechanisms and outcomes of trauma during pregnancy are numerous and heterogeneous the details of which are beyond the scope of this chapter. There are, however, certain features of specific injuries that might impact triage or treatments of pregnant patients. Mechanisms and injuries that occur in close proximity to the uterus, i.e., pelvis and abdomen, often portend worse outcomes for the fetus. For example, the presence of a pelvic fracture is an independent risk for stillbirth independent of gestational age [4]. This was further demonstrated by Cannada et al. who noted a fetal death rate of 30% if the patients suffered either pelvic or acetabular fracture [5]. Likewise, severity of injury in an MVC is directly related to the usage of seatbelts, as well as whether or not frontal/lateral airbags were present [6, 7]. Gestational age at the time of injury will also directly impact risk to the fetus. For example, abdominal injuries in parturients less than 12 weeks gestation are less likely to cause fetal injury as the uterus is still within the confines of the bony pelvis [8]. As the pregnancy progresses abdominal viscera are pushed cephalad with the uterus mid abdomen. It is therefore not surprising that there is a very high fetal mortality rate for penetrating injuries (40-65%) in the third trimester [9]. Risk of fetal death is also directly related to the severity of maternal injuries as well as the American Association for the Surgery of Trauma Organ Injury Scale for the gravid uterus (See Table 36.1) [10, 11].