CT should be considered for evaluation of all pregnant patients who experience blunt trauma, Tennessee investigators have concluded.
CT identified several types of injury associated with an increased risk of fetal demise, including placental abruption, placental infarction, and devascularization. In particular, absence of placental enhancement on CT or evidence of uterine rupture carries a high probability of fetal death, Dr. Catherine Lowdermilk reported at an RSNA scientific presentation.
The findings came from a retrospective review of 48 pregnant patients who experienced blunt trauma and were seen at two level I trauma centers. All had helical CT imaging during the course of their evaluation.
Automobile accidents were the most common cause of injury. In 40% of the cases, no maternal or fetal injuries were detected. In 31% of the cases, only nonuterine maternal injuries occurred. The remaining cases involved both maternal and fetal injuries.
The maternal death rate was 10%, and most of the deaths were due to head injuries, said Lowdermilk, a radiologist at the University of Tennessee. The fetal death rate was 33%, including fetal deaths secondary to maternal death.
CT did not detect fetal injuries, but the imaging technique did identify high-risk situations. For example, CT showed absence of placental enhancement or uterine rupture in 10 patients, and eight of the fetuses did not survive. Placental abruption, retroperitoneal hemorrhage, acute placental infarction, and ovarian vein hemorrhage were ominous signs detected by CT.
"Blunt trauma causes unique injuries that must be detected quickly," Lowdermilk said. "Placental abruption and devascularization are the most likely injuries, and CT readily detected those. In two cases, CT detected injuries missed by other imaging modalities. As a result, we believe CT should be considered for the evaluation of all pregnant patients who present with blunt trauma."
