Laminaria versus extra-amniotic saline solution infusion for cervical ripening in second-trimester labor inductions.

OBJECTIVE: The aim of this study was to determine which cervical ripening method, laminaria placement or extra-amniotic saline solution infusion, was associated with the shorter interval from induction to delivery in the second trimester. STUDY DESIGN: Women admitted for indicated second-trimester labor induction with an unfavorable cervix were randomly assigned to receive either intracervical placement of laminaria (n = 25) or extra-amniotic saline solution infusion (n = 25) with concurrent concentrated oxytocin and vaginally administered prostaglandin E2 (10 mg every 6 hours). Treatment success was defined as an interval from induction to delivery of < or =24 hours. RESULTS: Maternal age, race, parity, gestational age, and initial cervical dilatation were similar between the groups. Indications for uterine evacuation were also similar and included fetal death (n = 7), aneuploidy (n = 20), fetal structural anomaly (n = 18), and maternal indications (n = 4). There was no difference in the mean intervals from induction to delivery (laminaria, 16 +/- 8 hours, vs extra-amniotic saline solution infusion, 17 +/- 10 hours) or the number of treatment successes (laminaria, n = 23, vs extra-amniotic saline solution infusion, n = 21). Retained placenta, live birth, and hemorrhage occurred with similar frequencies in the two groups. CONCLUSION: Relative to laminaria, extra-amniotic saline solution infusion did not shorten the induction-to-delivery interval in women undergoing indicated second-trimester labor induction with concentrated oxytocin and low-dose vaginally administered prostaglandin E2.

Cardiovascular effects of intravaginal misoprostol in the mid trimester of pregnancy.

OBJECTIVE: Our aim was to evaluate the cardiovascular effects of high-dose intravaginal misoprostol administration by means of transthoracic electrical bioimpedance monitoring. STUDY DESIGN: Healthy women undergoing mid trimester pregnancy interruption with intravaginal misoprostol were eligible for this prospective observational study. Baseline blood pressure was obtained for 1 hour and transthoracic electrical bioimpedance monitoring was performed before misoprostol administration, 600 microg vaginally. Posttreatment assessments were made every 15 minutes for a total of 4 hours, with patients in a left lateral recumbent position. Heart rate, mean arterial pressure, cardiac index, stroke index, systemic vascular resistance index, and end-diastolic volume index were determined. Measurements were averaged for 30-minute intervals and reported as mean +/- SD. Statistical analyses included the paired t test and repeated-measures analysis of variance. RESULTS: Nine women consented to have transthoracic electrical bioimpedance monitoring, and no statistically significant changes in any of the measured cardiac parameters for the 4-hour monitoring interval were noted. Direct comparisons between the pretreatment and 2-hour posttreatment intervals (reported time peak of blood misoprostol levels) also revealed no significant differences in the cardiovascular index values. CONCLUSION: High-dose intravaginal misoprostol in the mid trimester does not alter maternal cardiac function as measured by transthoracic electrical bioimpedance.

Second-trimester plasma homocysteine levels and pregnancy-induced hypertension, preeclampsia, and intrauterine growth restriction.

OBJECTIVE: The purpose of this study was to determine whether second-trimester plasma homocysteine levels are elevated among women whose pregnancies are subsequently complicated by pregnancy-induced hypertension, preeclampsia, or intrauterine growth restriction. STUDY DESIGN: Women with normal but relatively low plasma zinc levels were randomly assigned to receive zinc supplementation or placebo from 19 weeks' gestation until delivery. Plasma homocysteine concentration and plasma and erythrocyte folate levels were determined for all available stored samples (zinc group, 231/294; placebo group, 206/286) at 26 and 37 weeks' gestation. Among all women with available samples, pregnancy-induced hypertension (n = 12) or preeclampsia (n = 4) developed in 16 women, and 22 pregnancies were complicated by intrauterine growth restriction. RESULTS: Mean homocysteine levels in women with pregnancy-induced hypertension and preeclampsia were similar to those of control subjects at 26 weeks' gestation but were significantly higher at 37 weeks' gestation. Homocysteine levels were similar between women with pregnancies complicated by intrauterine growth restriction and control subjects at both time points. CONCLUSION: Second-trimester plasma homocysteine concentrations do not predict the subsequent development of pregnancy-induced hypertension, preeclampsia, and intrauterine growth restriction.

A randomized, double-blind, hemodynamic evaluation of nifedipine and labetalol in preeclamptic hypertensive emergencies.

OBJECTIVE: Our purpose was to compare the hemodynamic effects of orally administered nifedipine and intravenously administered labetalol in preeclamptic hypertensive emergencies. STUDY DESIGN: Our study was a randomized, double-blind evaluation of nifedipine and labetalol in women with preeclampsia and a systolic blood pressure >170 mm Hg or a diastolic blood pressure >105 mm Hg. Nifedipine or labetalol and placebo were given, so patients received both tablet and intravenous solution. Hemodynamic parameters at dosing and at 15, 30, 60, and 120 minutes were recorded. Outcome measures were cardiac index, systemic vascular resistance index, mean arterial pressure, and heart rate. Data were analyzed by repeated-measures analysis of variance (Friedman test) with Dunn posttests, the Mann-Whitney U test, and the chi(2) test with the Yates correction. Significance was set at P <.05. RESULTS: At dosing, the nifedipine group (n = 6) had a cardiac index of 3.08 +/- 0.51 L/min per square meter. There was a 43% increase in the cardiac index after nifedipine administration (P =.0008). There was no significant effect in the labetalol group (P =.697). There was a significant decrease in the systemic vascular resistance index after nifedipine dosing (P =.002) but no significant effect on this index after labetalol use (P =.479). The mean arterial pressure was significantly affected in both groups as follows: nifedipine, P =. 001; labetalol, P =.004. The postanalysis showed significance at 60 minutes for both. An insignificant increase in heart rate with nifedipine (P =.147) and a significant decrease with labetalol (P =. 034) were noted. CONCLUSIONS: Nifedipine increases cardiac index, whereas labetalol may not do so.

Hemodynamic effects of oral nifedipine in preeclamptic hypertensive emergencies.

OBJECTIVE: Our purpose was to evaluate the hemodynamic effects of oral nifedipine in preeclamptic hypertensive emergencies. STUDY DESIGN: A prospective observational study of the hemodynamic effects of oral nifedipine was conducted with severely preeclamptic patients receiving magnesium sulfate infusion during a hypertensive emergency. Patients were eligible for the study if systolic blood pressure was > or = 170 m Hg or the diastolic blood pressure was > or = 105 mm Hg on repeat measurements 15 minutes apart at > or = 24 weeks' gestation. Nifedipine was given with an initial dose of 10 mg orally followed by 20 mg orally every 20 minutes until systolic blood pressure was > 160 mm Hg and the diastolic blood pressure was < 100 mm Hg, or for a total of five doses. Patients were hemodynamically monitored in the lateral recumbent position by thoracic electrical bioimpedance before during, and after oral nifedipine dosing. Cardiac index, systemic vascular resistance index, mean arterial pressure, heart rate, and stroke index were all recorded at baseline and during treatment. Data were analyzed by analysis of variance for repeated measures (alpha 0.05) and paired t tests, baseline versus 15 minutes (alpha 0.01). RESULTS: Ten severely preeclamptic patients at 33.2 +/- 3.0 (mean +/- SD) weeks' gestation were enrolled in the study. Mean arterial pressure measurements taken at baseline, 0.25, 0.5, 1, and 4 hours were 133 +/- 10, 119 +/- 8, 109 +/- 8 89 +/- 12, and 100 +/- 13 mm Hg (mean +/- SD, p < 0.0001, analysis of variance repeated measures). Cardiac index increased over time (p = 0.0011, analysis of variance repeated measures). There was no significant effect on maternal heart rate or stroke index. No periodic fetal heart rate changes were noted. One patient had nausea. CONCLUSION: Oral nifedipine appears to be an effective antihypertensive agent in preeclamptic hypertensive emergencies. A steady decrease in mean arterial pressure, systemic vascular resistance, and a mirrored increase in cardiac index are noted.

Autologous blood donation with placenta previa: is it feasible?

Autologous blood donation has been recommended for patients with placenta previa. We hypothesized that premature delivery, preexisting anemia, and bleeding would limit its utilization. We reviewed the charts of all patients admitted with placenta previa between July 1, 1989, and April 30, 1992. To be eligible for autologous donation we assumed that the patient would need to be asymptomatic with a hematocrit 34% or higher at 32 weeks' gestation. Eighty-eight patients were admitted with placenta previa, 12 (14%) of whom were eligible for autologous donation. Two eligible patients required transfusion at delivery and four delivered prior to 34 weeks. Few patients with placenta previa are eligible for autologous donation and although two would have used their autologous units, twice as many may have been compromised by recent autologous donation. We conclude that autologous donation is not feasible in a majority of patients with placenta previa and is of limited usefulness in its management.

Favorable hemodynamic effects of magnesium sulfate in preeclampsia.

OBJECTIVE: Our purpose was to evaluate the hemodynamic effects of magnesium sulfate in preeclamptic and preterm labor patients. STUDY DESIGN: Fifteen preeclamptic patients at 32.4 +/- 3.3 (mean +/- SD) weeks' gestation and 11 preterm labor patients (31.3 +/- 2.8 weeks) were hemodynamically monitored in the lateral recumbent position by thoracic electrical bioimpedance (BoMed, Irvine, Calif.) before and during high-dose magnesium sulfate bolus and infusion. Cardiac index, systemic vascular resistance index, mean arterial pressure, heart rate, and stroke index were all recorded at baseline and during magnesium sulfate infusion. All patients received a standard crystalloid infusion. Data analysis continued until the patient received epidural placement or other antihypertensive therapy or was delivered. RESULTS: At baseline the systemic vascular resistance index was 2465 +/- 718 F.ohm/m2 and the cardiac index was 3.6 +/- 1.0 L/min/m2 for the preeclamptic patients. These were significantly different compared with the preterm labor patients, who had a systemic vascular resistance index of 1377 +/- 563 F.ohm/m2 and 4.6 +/- 1.2 L/min/m2. Magnesium sulfate infusion resulted in a rapid, sustained fall in systemic vascular resistance and a rise in cardiac index in the preeclamptic patient. This effect was evident at least 4 hours after initiation of the bolus and infusion. In the preterm labor patients the hemodynamic effects of magnesium sulfate were minimal and were noted only during the magnesium sulfate bolus. CONCLUSION: Magnesium sulfate infusion appears to have a prolonged hemodynamic effect in the preeclamptic patient. Sustained reduction in systemic vascular resistance and an increase in cardiac index is found in patients with preeclampsia but not in preterm labor.

Attenuated proestrous luteinizing hormone surges in middle-aged rats are associated with decreased pituitary luteinizing hormone-beta messenger ribonucleic acid expression.

OBJECTIVE: This study determined whether attenuated preovulatory luteinizing hormone surges in aging rats are associated with a decrease in pituitary luteinizing hormone content or luteinizing hormone beta-messenger ribonucleic acid expression on proestrus. STUDY DESIGN: Blood samples were taken every 90 minutes from 1:30 to 10:30 PM on proestrus in young (n = 8) and middle-aged (n = 12), regularly cyclic rats for plasma luteinizing hormone determination. On the next proestrus at 12 noon, rats were killed and the pituitaries were removed for luteinizing hormone content determination by radioimmunoassay and luteinizing hormone beta-messenger ribonucleic acid expression by dot blot analysis. Results were analyzed by one-way analysis of variance. RESULTS: Seven of the middle-aged rats had attenuated luteinizing hormone surges while the remaining five females had surges similar to those of young rats. On the next proestrus, all rats had similar quantities of pituitary luteinizing hormone. However, luteinizing hormone beta-messenger ribonucleic acid expression in middle-aged rats with attenuated luteinizing hormone surges was lower (p less than 0.05) than that of middle-aged and young rats with normal surges. CONCLUSION: Decreased luteinizing hormone beta-messenger ribonucleic acid expression, but not pituitary luteinizing hormone content at 12 noon on proestrus is correlated with attenuated luteinizing hormone surges in middle-aged rats.