also changed our practice of universal seizure prophylaxis for all women with gestational hypertension to one of selective prophylaxis given only to women who met our criteria for severe gestational hypertension. These criteria, shown in Table 40-15, included women with :2+ proteinuria measured by dipstick in a catheterized urine specimen.
Following this protocol change, 60 percent of 6518 women with gestational hypertension during a 4Y2-year period were given magnesium sulfate neuroprophylaxis. The remaining 40 percent with nonsevere hypertension were not treated, and of these, 27 women developed eclamptic seizures-1 in 92. The seizure rate was only 1 in 358 for 3935 women with criteria for severe disease who were given magnesium sulfate, and thus these cases were treatment failures.
To assess morbidity, outcomes in 87 eclamptic women were compared with outcomes in all 6431 noneclamptic severely hypertensive women (Alexander, 2006). lthough most maternal outcomes were similar, almost a fourth of women with eclampsia who underwent emergent cesarean delivery required general anesthesia. his is a great concern because eclamptic women have laryngotracheal edema and are at a higher risk for failed intubation, gastric acid aspiration, and death. Neonatal outcomes were also a concern because the composite morbidity was increased tenfold in eclamptic compared with noneclamptic women-12 versus 1 percent, respectively. These outcomes included cord artery pH <7.0; 5-minute Apgar score <4; or unanticipated admission of a term newborn to an intensive care nursery.
Thus, if one uses the Parkland criteria for nonsevere gestational hypertension, approximately 1 of 100 such women who are not given magnesium sulfate prophylaxis can be expected to have an eclamptic seizure. A fourth of these women likely will require emergent cesarean delivery with attendant maternal and perinatal morbidity and mortality from general anesthesia. From this, the major question regarding management of nonsevere gestational hypertension remains whether it is acceptable to avoid unnecessary treatment of 99 women to risk eclampsia in one? he answer appears to be yes as suggested by the 20 13 Task Force. At Parkland Hospital, we only give magnesium neuroprophylxis to women with severe criteria.
During the past 20 years, the use of conduction analgesia for women with preeclampsia syndrome has proven ideal. Initial problems with this method included hypotension and diminished uterine perfusion caused by sympathetic blockade in preeclamptic women, with already attenuated hypervolemia. But pulmonary edema was mitigated by techniques that used slow induction of epidural analgesia with dilute solutions of anesthetic agents. his countered the need for rapid infusion of large volumes of crystalloid or colloid to correct maternal hypotension from neural blockade (Hogg, 1999; Wallace, 1995). These techniques are described in detail in Chapter 25 (p. 496). Importantly, epidural blockade avoids general anesthesia, in which the stimulation of tracheal intubation may cause sudden severe hypertension. Such blood pressure spikes, in turn, can cause pulmonary edema, cerebral edema, or intracranial hemorrhage. Finally, tracheal intubation may be particularly diicult and thus hazardous in women with airway edema due to preeclampsia (American College of Obstetricians and Gynecologists, 20 17b).