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Unlike other operations in which the patient is primarily concerned with himself or herself, the pregnant woman is usually concerned for her infant's welfare.
The anesthesia provider must be aware of the various physiologic changes of pregnancy and incorporate them into the anesthetic plan. These changes may affect various concurrent diseases if present.
The central nervous system effects of pregnancy include a reduced local anesthetic requirement when these agents are administered intrathecally or epidurally.
Pregnant patients in the third trimester and symptomatic patients in the first/second trimester should be considered at risk for aspiration during general anesthesia.
There is extremely weak evidence that surgery during the first trimester is linked to central nervous system defects in the fetus.
Fetal heart rate monitoring is possible during some surgical procedures, but it is not universally applied in the United States.
Preterm labor and delivery remain the leading cause of perinatal morbidity and mortality in the United States. Preterm labor is difficult to control with medication, with the most promising being the calcium channel blocking drugs. Magnesium sulfate is frequently used for neuroprotection in the preterm neonate.
The etiology of preeclampsia remains to be elucidated, but it is believed to be triggered by a paternal antigen in a susceptible mother.
Magnesium sulfate is the most effective medication for the prevention of seizures in those with preeclampsia.
Labetalol is the preferred drug for the control of blood pressure in mothers with preeclampsia. Antihypertensive medication does not treat the disease process; rather it is used to prevent intracerebral hemorrhage.
The 2 causes of antepartum hemorrhage are placenta previa and placental abruption. With the increase in cesarean deliveries, there is a high risk of placenta accreta in patients with previous cesarean delivery and placenta previa.
The perinatal transmission of human immunodeficiency virus (HIV) is low if the viral load is less than 1000 copies/mL and these patients do not require cesarean delivery. If the viral load is greater, cesarean delivery may decrease the risk of perinatal transmission.
Aggressive treatment of gestational diabetes mellitus, even mild gestational diabetes, with diet modification, oral agents, and insulin, is associated with improved maternal and neonatal outcome.
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One of the most rewarding as well as challenging aspects of anesthesia is caring for the parturient because it involves 2 patients, the mother and the fetus. When formulating an anesthetic plan, the outcomes for both patients must be considered, although usually the ultimate welfare of the mother guides final management decisions. Fortunately, in most circumstances, optimal care of the mother provides good care of the fetus. Both preoperative evaluation and formulation of the anesthetic plan require an understanding of the physiologic changes that accompany pregnancy. These physiologic changes result from alterations in the hormonal milieu (accounts for the changes early in pregnancy) and from the mechanical factors of the enlarging uterus (accounts for most of the changes later in pregnancy).
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Cardiovascular System
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Pregnancy causes an increase in maternal cardiac ...