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Chapter 151 Hematologic Changes in Pregnancy 2207

causes hepatocellular injury. Patients can develop right upper quad- when signs and symptoms of preeclampsia or HELLP develop. In a
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rant pain if intraparenchymal or subcapsular hemorrhage occurs. clinically stable woman, vaginal delivery can be attempted. When
DIC was observed in 21% of patients with HELLP in one series, and cesarean section is required, transfusion of RBCs, platelets, and fresh
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placental abruption was seen in 16% of patients. Other manifesta- frozen plasma (FFP) is performed as necessary before and during
tions of HELLP syndrome include acute renal failure, pulmonary surgery. Severe hypofibrinogenemia should be treated with
edema, shock, cerebrovascular accident (CVA), eclampsia, retinal cryoprecipitate.
detachment, diabetes insipidus, and an increased incidence of cesar- Patients are monitored closely in the postpartum period. Magne-
ean section. sium should be continued for 12 to 48 hours after delivery and blood
HELLP syndrome is associated with high maternal and neonatal pressure controlled appropriately. Although hypertension typically
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mortality rates. Maternal mortality rates range from 1.1% to 24.2%. resolves within 6 weeks after delivery, some women require long-term
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The immediate cause of death is most often rupture of the liver, DIC, antihypertensive therapy. Coagulation and platelet abnormalities
acute renal failure, pulmonary edema or acute respiratory distress tend to resolve within 24 to 48 hours after delivery. Some patients,
syndrome (ARDS), shock, or CVA. Perinatal deaths resulting from however, experience an ongoing decline in platelet count and should
placental abruption, asphyxia, or extreme prematurity occur in 10% be followed until counts normalize. Postpartum eclampsia can
to 15% of patients. After delivery, infants born to women with pre- occur for up to 48 hours after delivery; thus patients and health
eclampsia or HELLP can develop a self-limited neonatal thrombocy- care providers should remain vigilant in monitoring for suggestive
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topenia. Uncertainty exists regarding whether infant thrombocytopenia signs and symptoms. Treatment options in the setting of severe
in these instances results from preeclampsia or HELLP itself or from postpartum preeclampsia and HELLP include corticosteroids and
a related complication such as neonatal sepsis. 88–90 HELLP recurs in plasmapheresis. 106,107
subsequent pregnancies of affected women in 3% to 27% of cases. In light of the morbidity and mortality associated with preeclamp-
There is also an increased risk of preeclampsia, placental abruption, sia and HELLP, considerable research has been focused on prevention
and preterm delivery in these pregnancies. 91–100 of these conditions. The efficacy of various preventive strategies,
In caring for a patient with preeclampsia or HELLP syndrome, including magnesium supplementation, low-dose aspirin, zinc supple-
the clinician’s primary concerns are the mother’s health and safety. mentation, antihypertensive drugs, and heparin therapy, among
The clinician must also consider the stage of pregnancy at time of others, has been the focus of observational studies, systematic reviews,
diagnosis, the condition of the fetus, and desires of the patient in and randomized trials. Initial small studies suggested that low-dose
making management decisions. Definitive treatment for preeclampsia aspirin reduces the risk of preeclampsia, although patients who
and HELLP involves delivery of the fetus; it is indicated for women received aspirin had a higher incidence of placental abruption and
who present after 34 weeks of gestation and those with evidence of bleeding. 108–115 Larger, randomized trials failed to confirm the benefit
multisystem dysfunction. However, conservative, supportive care of low-dose aspirin. 109,110
without immediate delivery can be pursued for women who are rela-
tively asymptomatic, hemodynamically stable, at less than 32 to 34
weeks of gestation, and without evidence of abnormal coagulation Thrombotic Thrombocytopenic Purpura–
parameters. 100,101 Magnesium sulfate, which reduces cerebral vasocon- Atypical Hemolytic Uremic Syndrome
striction and ischemia, should be administered for seizure prophy-
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laxis. Parenteral labetalol or hydralazine is given for blood pressure TTP and HUS/atypical HUS are also important considerations in
control. Systemic corticosteroids appear to lessen the risk of maternal the evaluation of pregnant women with thrombocytopenia (Chapter
ARDS and reduce neonatal complications when administered to 135). Similar to preeclampsia and HELLP syndrome, they are
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women who present at less than 34 weeks of gestation. In addition multisystem disorders associated with high morbidity and mortality
to these measures, volume status is closely monitored to prevent rates in the absence of appropriate therapy. Microvascular injury and
plasma volume expansion and ensure adequate urine output. platelet agglutination with resulting thrombocytopenia and microan-
Persistent right upper quadrant pain, which may herald a liver giopathic hemolytic anemia are pathologic hallmarks of TTP and
hematoma or rupture, hemodynamic instability, coagulation profile HUS (Fig. 151.1). They are rare conditions overall, but the incidence
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abnormalities, or a decline in clinical status, should prompt delivery of both increases in pregnancy. In the case of TTP, in fact, estimates
by cesarean section. As mentioned previously, delivery is also indi- suggest that approximately 10% of cases occur in pregnant or post-
cated if the fetus is at least 32 to 34 weeks of gestation at the time partum women. 117

A B
Fig. 151.1 MICROANGIOPATHIC HEMOLYTIC ANEMIA. Microangiopathic hemolytic anemia in
pregnancy, peripheral blood smear (A, B). Evidence of microangiopathy with the formation of schistocytes,
fragmented forms and spherocytes, associated with polychromasia and nucleated red blood cells (A, B, detail).