Advanced Trauma Life Support ATLS Student Course Manual 2018

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CHAPTER 12 n Trauma in Pregnancy and Intimate Partner Violence
Pregnancy causes major physiological changes
and altered anatomical relationships involving
nearly every organ system of the body. These
changes in structure and function can influence the
evaluation of injured pregnant patients by altering
the signs and symptoms of injury, approach and
responses to resuscitation, and results of diagnostic
tests. Pregnancy also can affect the patterns and severity
of injury.
Clinicians who treat pregnant trauma patients must
remember that there are two patients: mother and
fetus. Nevertheless, initial treatment priorities for
an injured pregnant patient remain the same as for
the nonpregnant patient. The best initial treatment
for the fetus is to provide optimal resuscitation of
the mother. Every female of reproductive age with
significant injuries should be considered pregnant
until proven otherwise by a definitive pregnancy
test or pelvic ultrasound. Monitoring and evaluation
techniques are available to assess the mother and fetus.
If x-ray examination is indicated during the pregnant
patient’s treatment, it should not be withheld because of
the pregnancy. A qualified surgeon and an obstetrician
should be consulted early in the evaluation of pregnant
trauma patients; if not available, early transfer to a
trauma center should be considered.
Anatomical and Physiological
AlteRAtions of Pregnancy
An understanding of the anatomical and physiological
alterations of pregnancy and the physiological relationship
between a pregnant patient and her fetus is essential
to providing appropriate and effective care to both
patients. Such alterations include differences in anatomy,
blood volume and composition, and hemodynamics,
as well as changes in the respiratory, gastrointestinal,
urinary, musculoskeletal, and neurological systems.
Anatomical differences
The uterus remains an intrapelvic organ until
approximately the 12th week of gestation, when it
begins to rise out of the pelvis. By 20 weeks, the uterus
is at the umbilicus, and at 34 to 36 weeks, it reaches the
costal margin (n FIGURE 12-1; also see Changes in Fundal
Height in Pregnancy on MyATLS mobile app). During
the last 2 weeks of gestation, the fundus frequently
descends as the fetal head engages the pelvis.
As the uterus enlarges, the intestines are pushed
cephalad, so that they lie mostly in the upper abdomen.
Umbilicus
(maternal)
Symphysis
pubis
40
36
32
28
24
20
16
12
n FIGURE 12-1 Changes in Fundal Height in Pregnancy. As the
uterus enlarges, the bowel is pushed cephalad, so that it lies
mostly in the upper abdomen. As a result, the bowel is somewhat
protected in blunt abdominal trauma, whereas the uterus and its
contents (fetus and placenta) become more vulnerable.
As a result, the bowel is somewhat protected in blunt
abdominal trauma, whereas the uterus and its contents
(fetus and placenta) become more vulnerable. However,
penetrating trauma to the upper abdomen during
late gestation can result in complex intestinal injury
because of this cephalad displacement. Clinical signs
of peritoneal irritation are less evident in pregnant
women; therefore, physical examination may be less
informative. When major injury is suspected, further
investigation is warranted.
During the first trimester, the uterus is a thickwalled
structure of limited size, confined within the
bony pelvis. During the second trimester, it enlarges
beyond its protected intrapelvic location, but the small
fetus remains mobile and cushioned by a generous
amount of amniotic fluid. The amniotic fluid can
cause amniotic fluid embolism and disseminated
intravascular coagulation following trauma if the fluid
enters the maternal intravascular space. By the third
trimester, the uterus is large and thin-walled. In the
vertex presentation, the fetal head is usually in the
pelvis, and the remainder of the fetus is exposed above
the pelvic brim. Pelvic fracture(s) in late gestation
can result in skull fracture or serious intracranial
injury to the fetus. Unlike the elastic myometrium,
the placenta has little elasticity. This lack of placental
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