Page 1790 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 127: Critical Illness in Pregnancy 1259

vena caval obstruction, which exacerbates an already reduced venous Rh sensitization of Rh-negative patients, neonatal anemia, fetal cardiac
return from massive hemorrhage. Fetal monitoring is recommended as arrhythmias, and fetal exsanguination are potential complications of
fetal distress in the setting of obstetric hemorrhage indicates hemody- fetomaternal hemorrhage. 50
namic compromise. 3 A high Injury Severity Score, a low Glasgow Coma Score, acidemia,
An obstetric evaluation should be sought as soon as hemorrhage is hypotension, and fetal bradycardia are all associated with an increased
suspected or recognized. A thorough pelvic examination is necessary risk of fetal death. However, a low injury severity score does not rule
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to identify potential bleeding sources; general anesthesia may be neces- out fetal compromise, and performing a fetal assessment is recom-
sary to facilitate this. Uterine atony is treated with bimanual uterine mended for most pregnant patients with trauma. There is some litera-
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massage, bladder drainage, uterotonics, and removal of any retained ture to suggest that antenatal trauma may be a cause of cerebral palsy;
placental products. 36,39 A full bladder may impede uterine contractions, this observation awaits confirmation and further investigation. 51
and bladder catheterization is indicated if a patient is unable to void.
https://kat.cr/user/tahir99/
Intravenous oxytocin is a first line uterotonic, although its use indicates Management: The initial management of pregnant trauma patients is
monitoring for hyponatremia. Ergot preparations are alternative first similar to that of other trauma patients, with a few important consider-
line agents; since these can raise blood pressure and have been associ- ations. If airway management is required, it should be performed by an
ated with cerebral hemorrhage, they are contraindicated in hyperten- experienced individual. Resuscitation should be directed at maintaining
sive states. Prostaglandins, such as misoprostol, are other alternative the expanded circulating volume of pregnancy. Left uterine displacement
39
agents. While generally well tolerated, prostaglandins may cause hypo- should be performed whenever indicated and permitted by the clinical
36
tension, bronchoconstriction, or intrapulmonary shunt, and should be situation. If there is no overt vaginal bleeding, a pelvic examination
avoided in patients with underlying cardiac or pulmonary disease. 28,30 should be performed to evaluate for tenderness, or for the presence of
Retained placental products require curettage. For refractory bleeding blood, urine, or amniotic fluid; nitrazine paper can identify amniotic
due to uterine atony or pelvic trauma, selective arterial embolization, fluid and confirm rupture of amniotic membranes. The diagnosis of
uterine suturing, uterine packing or balloon tamponade are interven- pelvic or abdominal injury can usually be made by imaging, where com-
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tional options that should be considered early. If these measures fail puted tomography is generally more sensitive than ultrasonography.
28
and bleeding is life threatening, hysterectomy may be necessary. Urgent The approach to fetal assessment is guided by gestational age. If the esti-
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hysterectomy in the setting of uncontrollable postpartum hemorrhage is mated gestational age is less than 20 to 23 weeks, fetal heart tones should
high risk but can be lifesaving. be interrogated; ultrasound is often the most effective way to accomplish
■ TRAUMA diotocographic monitoring, which includes measurement of uterine
this. When the estimated gestational age is greater than 23 weeks, car-
Trauma is a leading nonobstetric cause of maternal mortality. Motor activity and Doppler assessment of fetal cardiac activity, should be
performed for at least 4 hours. Cardiotocographic monitoring can iden-
vehicle accidents, falls, and assaults account for the vast majority of tify uterine contractions, placental abruption, or signs of fetal distress.
trauma cases that result in hospital admission. Gun-shot wounds, Fetomaternal hemorrhage is identified by the Kleihauer-Betke test, a test
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suicide attempts, and burns are less common. Maternal deaths are most for fetal hemoglobin in the maternal circulation. Maternal Rh sensitiza-
often due to head injury or hemorrhagic shock. Fetal deaths are most tion can be prevented by administration of Rh (D) immune globulin.
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often the result of injuries related to motor vehicle accidents (82%), gun- If maternal death occurs despite aggressive resuscitation and if the
O
shot wounds (6%), or falls (3%). The risk of maternal and fetal death is fetus is alive and undelivered, immediate consideration should be given
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greatest for unrestrained passengers in a motor vehicle accident. As the to postmortem cesarean section. In a review of over 150 cases, the
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gravid uterus grows, it is increasingly susceptible to deceleration injury, outcomes of postmortem cesarean section were significantly related to
and increasingly likely to be directly damaged by blunt or penetrat- gestational age, and were inversely related to the length of time between
ing trauma. As borderline tachycardia and supine hypotension in late maternal death and delivery. 53
pregnancy from uterine obstruction of the vena cava do not necessarily
in the gravid trauma patient can be difficult. When possible, left lateral ■ CARDIAC DYSFUNCTION
indicate blood loss, the identification of a decreased circulating volume
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displacement of the uterus will be helpful in the evaluation. Pregnancy Cardiac dysfunction in pregnancy may be due to pre-identified or de
may also mask findings of peritoneal irritation, and a high index of sus- novo conditions. In addition, prior subclinical heart disease may mani-
picion is warranted for mild peritoneal signs. fest for the first time as a result of the increased cardiovascular demands
Preterm labor is the most common complication of trauma, occurring of pregnancy. Cardiac dysfunction is associated with increased maternal
in 6% of pregnant trauma patients. Premature rupture of membranes and fetal morbidity and mortality, and is an increasing cause of critical
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and direct fetal injury are less common complications. Hemorrhage illness in pregnancy.
is the most common serious complication of trauma, accounting for More patients with congenital heart disease are surviving to repro-
most cases of maternal and fetal demise. The cephalad displacement of ductive age. Complication rates of congenital heart disease in preg-
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abdominal contents in pregnancy increases the risk of visceral injury, nancy are substantial. In the mother, pulmonary edema and arrhythmias
including splenic rupture, from penetrating trauma of the upper abdo- are common, whereas preterm delivery, small for gestational age, and
men. Beyond 12 weeks of gestation, the urinary bladder is also a target respiratory distress are the most common complications in the neonate.
for injury as it is displaced into the abdominal cavity. Placental abrup- Risk factors for adverse outcomes in those with congenital heart disease
tion is the leading cause of trauma-related obstetric hemorrhage. Rapid include prior cardiac events, poor baseline functional class (New York
deceleration injury can cause placental abruption as a result of deforma- Heart Association class III or IV), cyanosis, significant aortic or mitral
tion of the elastic uterus around or away from the less elastic placenta. stenosis, or left ventricular systolic dysfunction. Mortality rates in
Abruption may manifest in vaginal bleeding, abdominal cramps, uterine recent reports are generally low, which likely reflect discouragement of
tenderness, amniotic fluid leakage, and maternal hypotension, but these pregnancy for those with advanced cardiac dysfunction, and improved
findings are not as reliable as widely believed and the clinical signs management of those who do become pregnant. However, patients with
may be subtle; cardiotocographic fetal monitoring is recommended as Eisenmenger syndrome, cyanosis, or pulmonary hypertension continue
the most reliable way to detect abruption. Uterine rupture is a less to have a high pregnancy-associated mortality. 55,56
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common complication of trauma, but can be catastrophic. A direct, Pregnancy can exacerbate or unmask underlying pulmonary hyper-
forceful blow to the abdomen is an important risk factor for uterine tension; more rarely pulmonary hypertension begins in pregnancy.
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rupture. Finally, traumatic injury can result in fetomaternal hemor- In the setting of pulmonary hypertension, the normal pregnancy-
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rhage, whereby blood loss from the fetal to maternal circulation occurs. associated decrease in pulmonary vascular resistance does not occur,

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