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CHAPTER 127: Critical Illness in Pregnancy 1263

Magnesium sulfate has been shown in numerous well-conducted
TABLE 127-8 Management of Severe Preeclampsia
studies, which are summarized in a recent Cochrane review, to prevent
Intervention Comment eclamptic seizures and placental abruption, and is superior to phenytoin
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Delivery Immediately if >36 weeks gestation and nimodipine. In patients with preeclampsia, magnesium reduces
the risk of eclampsia by half, and likely reduces the risk of maternal
Corticosteroids If between 24 and 34 weeks gestations
death. Magnesium sulfate also has been shown to be better than diaz-
Magnesium sulfate Loading dose 4 g IV over 15-20 minutes epam and phenytoin in preventing recurrent seizures in patients with
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Continuous infusion 1 g/h eclampsia. Magnesium sulfate should be given until 24 hours after
Labetalol See Table 127-9 delivery to all women with either severe preeclampsia or eclampsia.
Toxicity is decreased if, after a loading dose of 4 g IV, an infusion of
Hydralazine See Table 127-9 one gram/hour is given. Monitoring of serum magnesium levels is not
Surveillance Measure blood pressure at least every 2 hours routinely required at this dose as clinical effect can be assessed at the
bedside by monitoring deep tendon reflexes. 90
Frequent measurement of serum creatinine, magnesium,
hemoglobin, platelets, and liver function tests Pulmonary edema is managed conventionally. Patients with delayed
postpartum resolution of the HELLP syndrome marked by persistent
Fetal ultrasound and cardiotocography thrombocytopenia, hemolysis or organ dysfunction may benefit from
plasmapheresis. TTP or HUS can be difficult to distinguish from the
HELLP syndrome, and should be considered in the differential. The
management of intrahepatic hemorrhage with subcapsular hematoma
Preeclampsia may be mild or severe, and the aggressiveness of includes delivery, administration of blood products, and directed con-
therapy is based on disease severity and fetal maturity. Markers of trol of liver hemorrhage. Embolization of the hepatic artery is often
disease severity that should alert the physician to an increased risk successful, but evacuation of the hematoma and packing of the liver
of complications include systolic or diastolic blood pressures of ≥160 may be required.
and ≥110 mm Hg, respectively (especially after 24 hours of hospital-
ization), proteinuria ≥2 g in 24 hours or ≥ 100 mg/dL in a random ■ CARDIOPULMONARY RESUSCITATION
specimen, oliguria, pulmonary edema, or early onset disease (<34-35 The physiologic and anatomic changes of pregnancy must be taken
weeks). Elevation in systolic rather than diastolic blood pressure may into account when performing cardiopulmonary resuscitation (CPR)
correlate with risk of stroke. 105 on a gravid patient (Table 127-10). As reviewed, the gravid uterus may
In patients who are ≥36 weeks gestation, delivery is indicated as impede venous return, especially in late pregnancy. While CPR can be
removal of the placenta is the only curative therapy. Earlier in gestation, attempted with the patient tilted 30° in a left lateral decubitus position,
delivery is recommended for patients with severe preeclampsia, eclamp- this may impair compressions and manual leftward displacement of
sia, the HELLP syndrome, multiorgan involvement, or fetal distress. the uterus may be preferred. 110,111 In late pregnancy, the gravid uterus
Symptomatic disease and proteinuria are associated with an increased decreases chest wall compliance, and increased force may be required for
risk of adverse maternal outcomes. These patients and those with pro- adequate excursion of the sternum during compressions. A lower oxy-
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gressive disease should be hospitalized and observed closely. In selected gen reserve from increased oxygen consumption and a decreased FRC,
cases of early gestational age, conservative management with close and the aspiration risk of bagged valve mask ventilation are indications
monitoring at a tertiary perinatal center can lead to improved neonatal for expeditious intubation of the trachea. Until intubation is performed,
outcomes and may be appropriate. cricoid pressure should be applied. When defibrillation is clinically
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Blood pressure control is essential to prevent end organ damage but indicated, fetal monitoring devices should be removed to prevent arcing,
does not affect progression of the underlying disease process. While and defibrillation pads are placed as close to the chest wall as possible
hydralazine has been the traditional treatment, in the ICU setting to avoid pendulant breast tissue; standard doses of electrical energy
intravenous labetalol is often recommended. Dosing regimens for these are given. Advanced life support protocols are otherwise employed as
agents are outlined in Table 127-9. 106,107 Nitroprusside is relatively con- for nonpregnant patients. If magnesium overdose is a possibility, cal-
traindicated, and angiotensin-converting enzyme inhibitors are absolutely cium chloride should be given during resuscitation. Thrombolytic
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contraindicated in pregnancy. Calcium channel blockers are second line therapy has been used successfully in pregnant patients in shock from
agents for the treatment of hypertension in the setting of preeclampsia. suspected pulmonary embolism. 113,114 If CPR cannot generate a pulse
Long acting oral nifedipine may be given, as there are some data regard- or if resuscitation efforts are unsuccessful, emergency cesarean section
ing its safe use in pregnancy, but this does not have a rapid onset of should be considered. Especially in late pregnancy, this intervention can
action. Other calcium blocking agents are less well studied in this setting benefit both the mother and fetus if performed within 4 to 5 minutes of
precluding comments on their efficacy and safety. Diuretics should be an arrest: maternal circulation may dramatically improve with uterine
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used with caution, as they may aggravate the reduction in intravascular
volume that is often seen in preeclampsia.
TABLE 127-10 Modifications to ACLS for Pregnant Patients
– To resuscitate the fetus, you must resuscitate the mother.
TABLE 127-9 Drugs Used in the Management of Acute Hypertensive Crises – If possible, immediately summon obstetrics and anesthesiology.
in Pregnancy
– Designate a rescuer to displace the uterus to the left, or left tilt the patient 30° with a
Drug (pregnancy category) Regimen pillow under right hip.
Labetalol (C) Loading dose 10-20 mg IV, then 20-80 mg IV every – Ensure adequate chest compressions.
20-30 minutes until blood pressure is controlled or total – Intubate the trachea.
dose is 300 mg; can use continuous infusion of 1-2 mg/min
titrated until blood pressure is controlled – Remove fetal monitors prior to cardioversion and defibrillation.
Hydralazine (C) Loading dose 5 mg IV, then 5-10 mg IV every 20-40 minutes – Avoid femoral vein access; antecubital, jugular, and subclavian lines are preferable.
until blood pressure is controlled or total dose is 20 mg; – If there is no return of spontaneous circulation and the estimated gestational age is
repeat every 3 hours as needed >25 weeks, consider emergency caesarian section.

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