Comparison of glyburide and insulin for the management of gestational diabetics with markedly elevated oral glucose challenge test and fasting hyperglycemia.

OBJECTIVE: To compare the effectiveness of glyburide and insulin for the treatment of Gestational diabetes mellitus (GDM) in women who had OGCT >or=200 mg/dl and fasting hyperglycemia. STUDY DESIGN: A retrospective study was performed among a subset of women treated with glyburide or insulin for GDM from 1999 to 2002 with an OGCT >or=200 mg/dl and pretreatment fasting plasma glucose >or=105 mg/dl. Exclusion criteria included pretreatment fasting >or=140 mg/dl, gestational age >or=34 weeks and multiple gestation. Maternal and neonatal outcomes were assessed. Statistical methods included bivariate and multivariable logistic regression analyses. RESULTS: In 1999 to 2000, 78 women were treated with insulin; in 2001 to 2002, 44 of 69 (64%) received glyburide. There were no statistically significant differences between the two groups with regards to mean OGCT (230+/-25 vs 223+/-23 mg/dl, P=0.07) and mean pretreatment fasting (120+/-10 vs 119+/-11 mg/dl, P=0.45). Seven women (16%) failed glyburide. Women in the insulin group were younger (31.5+/-5.8 vs 35.2+/-4.7 years, P<0.001) and had a higher mean BMI (32.4+/-6.4 vs 29.1+/-5.8 kg/m(2), P=0.003) compared to glyburide group. There were no significant differences in birth weight (3524+/-548 vs 3420+/-786 g, P=0.65), macrosomia (19 vs 23%, P=0.65), pre-eclampsia (12 vs 11%, P=0.98) or cesarean delivery (39 vs 46%, P=0.45). Neonates in the glyburide group were diagnosed more frequently with hypoglycemia (34 vs 14%, P=0.01). When controlled for confounders, macrosomia was found to be associated with glyburide treatment (OR 3.5, 95% CI 1.1 to 11.4). CONCLUSION: In women with GDM who had a markedly elevated OGCT and fasting hyperglycemia, glyburide achieved similar birth weights and delivery outcomes but was associated with an increased risk of macrosomia. The possible increased risk of neonatal hypoglycemia in the glyburide group warrants further investigation.

Monitoring women at risk for preterm labor.

BACKGROUND: Preterm birth is a major cause of perinatal morbidity and mortality. Whether the rate of preterm birth can be reduced by frequent contact between nurses and pregnant women or home monitoring of uterine activity is not known. METHODS: We randomly assigned 2422 pregnant women with known risk factors for preterm labor (including 844 women who were pregnant with twins) to receive education and to have one of the following: weekly contact with a nurse, daily contact with a nurse, or daily contact with a nurse and home monitoring of uterine activity. The nurses elicited the women's own assessments of their symptoms and signs of preterm labor. The primary end point was the incidence of birth at less than 35 weeks' gestation. Secondary end points included cervical status at the time preterm labor was diagnosed and birth weight. RESULTS: There were no significant differences among the groups in the incidence of birth at less than 35 weeks (14 percent in the weekly-contact group, 13 percent in the daily-contact group, and 14 percent in the home-monitoring group), in the mean amount of cervical dilatation at the time preterm labor was diagnosed (1.8 cm, 1.5 cm, and 1.4 cm, respectively), or in such neonatal outcomes as birth weights of less than 1500 g or less than 2500 g. However, daily contact with a nurse increased the mean number of unscheduled visits to obstetricians (1.2 in the weekly-contact group, 1.8 in the daily-contact group, and 2.3 in the home-monitoring group) and the proportion of women who received prophylactic tocolytic drugs (12 percent, 14 percent, and 19 percent, respectively). CONCLUSIONS: Women who have daily contact with a nurse, with or without home monitoring of uterine activity, have no better pregnancy outcomes than women who have weekly contact with a nurse.

Fetal heart rate variability and cerebral oxygen consumption in fetal sheep during asphyxia.

This study was designed to examine the relationship between fetal heart rate variability and fetal cerebral oxygen uptake. Fetal sheep were chronically prepared with catheters and electrodes to determine cerebral blood flow (microsphere method), cerebral arteriovenous oxygen difference, and the electrocardiogram. An adjustable occluder was placed on the maternal common internal iliac artery to induce fetal asphyxia by reducing uterine blood flow. Fetal heart rate variability tended to decrease in the first 11 min of asphyxia, when cerebral oxygen consumption was approximately 53% of control. Despite stable cerebral oxygen consumption and worsening metabolic acidosis, however, fetal heart rate variability progressively returned towards normal by 36 min. There was no relationship between the depression of FHR variability and the degree of reduction of cerebral oxygen consumption. Nor was there any relationship between an alteration in regional cerebral blood flow or myocardial blood flow and the return of FHR variability with increasing duration of asphyxia. We conclude that there is an association between loss of fetal heart rate variability and reduced cerebral oxygen consumption, but the reduced variability does not persist with time at this degree of reduced cerebral metabolism in fetal sheep. This appears to be at variance with human clinical experience. Among the explanations for this may be insufficiently severe asphyxia, a species difference, removal of an inhibitor to FHR variability, or progressive use of other substrates for metabolism.

Cerebral oxygen consumption during asphyxia in fetal sheep.

Cerebral blood flow and cerebral arteriovenous oxygen content difference were measured in 17 fetal sheep, and cerebral oxygen uptake was calculated. The measurements were made under control conditions and after profound fetal asphyxia induced of uterine blood flow for up to 90 min. In 14 of the fetal sheep, sequential measurements were made to examine hemodynamic changes and cerebral oxygen consumption at comparable intervals up to 36 min of asphyxia. These fetuses initially had elevated blood pressure and lowered heart rate became hypoxemic, hypercarbic, and acidotic. There was an initial decrease in cerebral oxygen consumption. Sequential measurements, however, showed a relative stability in this decreased oxygenation during 4 to 36 min of asphyxia despite a progressive metabolic acidosis. The cerebral fractional oxygen extraction remained unchanged despite a mean pH of 6.98 at 36 min. The calculated cerebral oxygen uptake during asphyxia in all 17 sheep was grouped according to whether the ascending aortic oxygen content was greater or less than 1.0 mmol/l. In the first group with mean ascending aortic oxygen content of 1.3 mmol/l, blood flow to the brain was increased and cerebral oxygen consumption was 85% of control. In the second group with mean arterial blood oxygen content of 0.8 mmol/l, there was a narrowing of the arteriovenous oxygen content difference, but no further increase in cerebral blood flow. Cerebral oxygen consumption was only 48% of control in this more asphyxiated group. We conclude that the degree of hypoxemia in the second group represents a point where physiologic mechanisms cannot compensate, and may be associated with neuronal damage.

Maternal anesthesia and the stressed fetus: effects of isoflurane on the asphyxiated fetal lamb.

The effects of maternal isoflurane-oxygen anesthesia (isoflurane, 1% inspired) were measured in eight pregnant ewes and their asphyxiated singleton fetuses. Stable fetal asphyxia, indicated by a stable fetal arterial pH of 7.1-7.2 units, was produced by maternal uterine artery occlusion. Maternal and fetal heart rates and blood pressures; maternal uterine artery flow; maternal arterial, fetal arterial, and sagittal sinus pH; and blood gas tensions were determined during an awake control period, during fetal asphyxia alone, and during fetal asphyxia plus isoflurane-oxygen. Measurements of representative fetal whole organ blood flows, cardiac output, and cerebral oxygen consumption were also made during each of the three experimental periods. During asphyxia alone regional and total brain, heart, and adrenal flows increased above control while flow to the spleen and carcass decreased. Similar responses were seen during asphyxia plus isoflurane-oxygen. Fetal arterial and sagittal sinus pH, base excess, po2, and oxygen saturation decreased, and hydrogen ion concentrations and pco2 increased during asphyxia alone and asphyxia plus isoflurane-oxygen. Cerebral oxygen consumption decreased significantly from control during asphyxia plus isoflurane-oxygen, whereas no significant changes occurred in cerebral oxygen delivery. These results support the conclusions that in the asphyxiated fetus: 1) acidosis is increased; 2) cardiac output is redistributed to vital organs; and 3) the balance of cerebral oxygen supply-to-demand is maintained during maternal isoflurane-oxygen anesthesia.

Maternal brain death during pregnancy. Medical and ethical issues.

We present in detail a case of a 27-year-old primigravida who was maintained in a brain-dead state for nine weeks. An apparently normal and healthy male infant weighing 1440 g was delivered. The newborn did well and was found to be growing and developing normally at 18 months of age. Although the technical aspects of prolonged life support are demanding and the economic costs are very high (+217,784), there are ample ethical arguments justifying the separation of brain death and somatic death and the maintenance of the brain-dead mother so that her unborn fetus can develop and mature.

KIE: Physicians and an ethicist at the University of California, San Francisco, present the details of the case of a pregnant, brain-dead woman whose vital functions were maintained for nine weeks until the delivery of a healthy infant at 31 weeks' gestation. Despite the technical difficulties involved and the economic costs incurred ($183,031 for maternal care and $34,703 for neonatal care), the authors conclude that ethical considerations support the decision on care. They argue that the woman was not injured; that nonmaleficence and beneficence toward the fetus require a rescue attempt if there is a reasonable chance of reaching fetal maturity; that maternal medical care may be more cost effective than prolonged neonatal support; and that the father's wishes were respected. Rather than proposing guidelines, they hold that decisions on prolonged maternal support should be based on the circumstances of each case.

Effect of halothane on regional cerebral blood flow and cerebral metabolic oxygen consumption in the fetal lamb in utero.

The effects of halothane on maternal and fetal hemodynamics, distribution of fetal cardiac output, regional cerebral blood flow, and fetal cerebral oxygen consumption were studied in the ewe (N = 9) using radionuclide-labeled microspheres. An adjustable uterine artery occluder was used to produce a controlled state of fetal asphyxia. Measurements were taken during three periods of study: 1) control, 2) asphyxia, and 3) asphyxia plus 15 min of 1% maternal halothane. The fetal cardiovascular response to asphyxia was acidosis, hypoxia, hypertension, bradycardia, and preservation of vital organ blood flows. There was a significant drop in maternal blood pressure when halothane was administered but uterine blood flow was maintained, 308 ml X min-1 during asphyxia versus 275 ml X min-1 with halothane. Fetal blood pressure during asphyxia plus halothane (54 mmHg) was significantly lower than that during asphyxia alone (59 mmHg), while heart rate was significantly higher: 172 beats per minute (bpm) versus 125 bpm (P less than 0.05). Despite these changes, the administration of halothane during asphyxia did not produce a reduction in vital organ flows. Cerebral blood flow was maintained: 357 +/- 37 ml X 100 g-1 X min-1 during asphyxia alone and 344 +/- 26 ml X 100 g-1 X min-1 after halothane administration (P = NS, mean +/- SEM). Cerebral oxygen delivery also was maintained: 8.3 +/- 0.8 ml X 100 g-1 X min-1 during asphyxia alone versus 9.7 +/- 1.5 ml X 100 g-1 X min-1 after halothane, compared with 11.2 +/- 1.1 ml X 100 g-1 X min-1 during the control period.(ABSTRACT TRUNCATED AT 250 WORDS)

Artifacts seen during CT pelvimetry: implications for digital systems with scanning beams.

During computed tomography (CT) pelvimetry of two pregnant women, bony abnormalities of the fetuses were noted on the scout images that were not confirmed at delivery. To explore the cause of these artifacts, specimen long bones were manipulated in various ways during CT scout imaging. Artifacts like those seen during in vivo imaging were found to be caused by motion of the object. The CT scout view is an example of an image produced by a digital system that uses a scanning beam. This type of digital system is being used for several types of body imaging including screening for scoliosis and chest radiography. Attention to motion artifacts should decrease diagnostic errors and aid further development of these systems.

Refractory status epilepticus in pregnancy. A case report.

Status epilepticus is an acute, life-threatening potential complication of pregnancy in the epileptic patient. It is important that obstetricians become familiar with the initial control of such seizure activity to decrease maternal and fetal morbidity and mortality.

Postpartum hypokalemic paralysis.

An attack of hypokalemic paralysis occurring in a 23-year-old woman during the immediate postpartum period of her fourth pregnancy is described. A flaccid paralysis of her extremities and markedly diminished deep tendon reflexes developed 3 hours after delivery, at which time her serum potassium level was found to be 1.7 mEq/liter. Hypokalemic paralysis has not been previously reported as an immediate postpartum complication. The pathophysiology and management of this condition are discussed, as are the treatment and follow-up of this specific patient.