P. Scott Barrilleaux

Interleukin-10 administration and bacterial endotoxin-induced preterm birth in a rat model.

OBJECTIVE To determine whether intrauterine infusion of interleukin‐10 prevents preterm delivery in rats treated with endotoxin. METHODS Pregnant rats underwent implantation of uterine catheters and were randomly assigned to receive intrauterine infusion of either normal saline, 50 μg lipopolysaccharide endotoxin, or 50 μg lipopolysaccharide with 500 ng interleukin‐10 administered either concurrently or 24 hours later. The interval from infusion to delivery for each group was recorded, along with the number of live born pups and their birth weight. We calculated that to obtain a power of 80%, assuming a 24‐hour difference in the treatment to delivery times between the test and control subjects, at least six animals would be needed in each group. RESULTS In females receiving lipopolysaccharide (50 μg) alone, the interval to delivery (P < .05), live birth rate (P < .05), and pup weight (P < .001) were reduced compared with the saline‐infused controls. In contrast, females receiving interleukin‐10 at the time of the endotoxin challenge or 24 hours after delivered at term with no difference in litter size or live birth weight compared with the controls. CONCLUSION Animals treated with both lipopolysaccharide and interleukin‐10, administered concurrently or 24 hours after the endotoxin challenge, delivered normal weight pups at term with a similar litter size as the saline‐infused controls. Interleukin‐10 appears to be effective in preventing endotoxin‐induced preterm birth and fetal wastage in pregnant rats.

Amniotic fluid index and single deepest pocket: weak indicators of abnormal amniotic volumes ☆

Objective To compare amniotic fluid index (AFI) with the single deepest pocket in the identification of actual abnormal amniotic fluid (AF) volumes. Methods One hundred seventy-nine women with singleton pregnancies at the University of Mississippi between March 1994 and June 1999 had ultrasound estimations of AF volume sequentially using the AFI and single deepest pocket techniques. Each woman subsequently had ultrasound-directed amniocentesis with dye-dilution and spectrophotometric calculation of actual AF volume. Results Actual AF volumes were low (under 5% by volume for gestational age) in 62 women, normal (5–95%) in 100 women, and high (more than 95%) in 17 women. An AFI up to 5 cm (sensitivity 10%, specificity 96%) and a single deepest pocket up to 2 cm (sensitivity 5%, specificity 98%) were similarly inadequate in identifying dye-determined low AF volumes. Likewise, AFI above 20 (sensitivity 29%, specificity 97%) and a single-deepest pocket above 8 cm (sensitivity 29%, specificity 94%) were poor in identifying dye-determined abnormally high volumes. Conclusion There was no difference between AFI and single deepest pocket techniques for identifying truly abnormal AF volumes. Both techniques were unreliable for identifying true AF volumes.

Pregnancy after classic cesarean delivery.

OBJECTIVE To describe maternal and perinatal outcomes after a prior classic cesarean delivery. METHODS A retrospective review was performed including all patients from 1990–2000 whose most recent pregnancy was preceded by classic cesarean delivery. RESULTS During the 11‐year period, there were 37,863 deliveries and 157 patients (0.4%) underwent classic cesarean operations. In the next pregnancy, one case of uterine rupture (0.6%, 95% confidence interval 0.1, 3.5) occurred at 29 weeks without preterm labor and resulted in fetal death. The prevalence of asymptomatic dehiscence was 9% (95% confidence interval 5, 15). There was no significant difference between patients with uterine dehiscence (n = 15) and patients with intact uteri (n = 141) with regard to maternal demographics, duration of labor, cervical dilatation at time of surgery, transfusion of packed red cells, bowel injury, postpartum endometritis, wound breakdown, thrombophlebitis, or umbilical arterial pH less than 7.00 (P > .05). Duration of labor, cervical dilatation, and gestational age at repeat cesarean delivery were poor predictors for uterine rupture or dehiscence. CONCLUSION Among patients with prior classic cesarean delivery, uterine rupture and dehiscence are neither predictable nor preventable. One in four patients will experience some form of maternal morbidity. Uterine rupture, although infrequent, can be fatal to the fetus. Uterine dehiscence, however, does not increase neonatal or peripartum maternal morbidity.

Ultrasound estimate of amniotic fluid volume : Color Doppler overdiagnosis of oligohydramnios

OBJECTIVE To determine if concurrent use of color Doppler affects ultrasound estimates of amniotic fluid (AF) volume. METHODS Study gravidas underwent ultrasound estimations of AF volume subjectively (visualization without measurements) and objectively (using amniotic fluid index [AFI]) and single‐deepest pocket techniques, without and with concurrent color Doppler. Amniocentesis with the dye‐dilution technique to measure actual AF volume was utilized for comparison. RESULTS Sixty‐seven women at a mean gestational age of 37.1 ± 2.5 weeks were entered into this investigation between June 1999 and March 2000. Dye‐determined AF volume was classified as low in 18 patients and as high in seven, with the remaining 42 within normal range. Using either ultrasound technique with color Doppler produced significantly lower estimates of AF volume (9.3 ± 4.9) compared to those without color ([11.6 ± 5], P < .001) for the AFI and (3.7 ± 1.5) with color compared to those without color ([4.5 ± 1.5], P < .003) for the single‐deepest pocket. Using AFI without color identified two of 67 (3%) of the pregnancies as having low fluid compared to 14 of 67 ([21%] P .002) using color. The increased classification of oligohydramnios with color did not accurately identify a greater number of dye‐determined low volumes; instead, the AFI with color mislabeled nine pregnancies with normal fluid as low. The diagnosis of dye‐determined low and high fluid volumes was not significantly different with or without color. CONCLUSION Concurrent use of color Doppler with AFI measurements leads to the overdiagnosis of oligohydramnios.

Hypertension therapy during pregnancy

Hypertension is the second most common medical condition to complicate pregnancy, ranking behind only anemia. Unlike the anemias, which infrequently cause serious gestational concern, the hypertensive disorders can have a significant impact on pregnancy and can produce a significant cost to the mother and baby in terms of morbidity and potential mortality. At a minimum, approximately 7–10% of all pregnancies are complicated by some form of hypertensive disease. In some populations, such as ours in Mississippi, as many as one in five mothers exhibit hypertension at some point during the antepartum, intrapartum, or postpartum periods. Hypertensive pregnant patients suffer greater risks for prematurity, intrauterine fetal demise, growth restriction, and abruptio placentae. They also have an increased risk of vascular injury with thrombotic microangiopathy and coagulopathy, cerebral hemorrhage, and multiorgan injury (especially kidney and liver) than do patients who are normotensive. In this chapter, we will review the current classification systems for patients with hypertensive disorders of pregnancy. We will consider the evidence for treating elevated blood pressure in these various disease settings and gestational periods and will review which medications merit consideration for therapy, as well as their shortcomings and side effects. Finally, we will briefly discuss areas of controversy that require further investigation.

Postpartum intravenous dexamethasone for severely preeclamptic patients without hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome: a randomized trial.

OBJECTIVE: We compared maternal outcomes for patients with severe preeclampsia who were managed postpartum with or without adjunctive intravenous dexamethasone. METHODS: This study was a randomized, blinded placebo-controlled clinical trial comparing the use of dexamethasone postpartum (10 mg–10 mg–5 mg–5 mg intravenously every 12 hours) with a saline control in patients with severe preeclampsia. The Student t and &khgr;2 tests were used for data analysis, with P < .05 considered significant. RESULTS: Data from 157 patients (77 patients receiving dexamethasone, 80 patients receiving placebo) who were treated during 2000–2003 were analyzed. Demographics, diagnostic criteria, baseline laboratory values, and postpartum outcomes were similar between groups. Although dexamethasone-treated patients had fewer returns (6.5% compared with 11.3%) to the labor/delivery/recovery unit for uncontrolled hypertension than control patients, no significant differences were found in blood pressure, antihypertensive requirements, laboratory values, length of hospitalization, interval urine output at 48 hours postpartum, or major maternal morbidity. Two control patients developed hemolysis, elevated liver enzymes, low platelets syndrome. CONCLUSION: Adjunctive use of intravenous dexamethasone for postpartum patients with severe preeclampsia does not reduce disease severity or duration. LEVEL OF EVIDENCE: I

Randomized trial of intermittent or continuous amnioinfusion for variable decelerations.

Objective To determine whether continuous or intermittent bolus amnioinfusion is more effective in relieving variable decelerations. Methods Patients with repetitive variable decelerations were randomized to an intermittent bolus or continuous amnioinfusion. The intermittent bolus infusion group received boluses of 500 mL of normal saline, each over 30 minutes, with boluses repeated if variable decelerations recurred. The continuous infusion group received a bolus infusion of 500 mL of normal saline over 30 minutes and then 3 mL per minute until delivery occurred. The ability of the amnioinfusion to abolish variable decelerations was analyzed, as were maternal demographic and pregnancy outcome variables. Power analysis indicated that 64 patients would be required. Results Thirty-five patients were randomized to intermittent infusion and 30 to continuous infusion. There were no differences between groups in terms of maternal demographics, gestational age, delivery mode, neonatal outcome, median time to resolution of variable decelerations, or the number of times variable decelerations recurred. The median volume infused in the intermittent infusion group (500 mL) was significantly less than that in the continuous infusion group (905 mL, P = .003). Conclusion Intermittent bolus amnioinfusion is as effective as continuous infusion in relieving variable decelerations in labor. Further investigation is necessary to determine whether either of these techniques is associated with increased occurrence of rare complications such as cord prolapse or uterine rupture.

Postpartum magnesium sulfate prophylaxis: a prospective trial utilizing clinical parameters to indicate duration of therapy for hypertensive diseases of pregnancy

Abstract Objective: To utilize patient clinical parameters to signal safe cessation of postpartum magnesium sulfate seizure prophylaxis for the spectrum of pregnancy-related hypertensive disorders. Methods: A prospective trial using clinical symptoms (absence of headache, visual changes, epigastric pain) and signs (sustained blood pressure less than 150/100, spontaneous diuresis) was used to signal safe cessation of intravenous magnesium sulfate postpartum in gravidas with preeclampsia, eclampsia, and HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Laboratory assessments (including proteinuria) were not used as criteria for drug discontinuation. Results: Five hundred three patients were enrolled and classified according to ACOG criteria for hypertensive disease. Maternal age, gestational age, and hours of magnesium therapy before delivery were not statistically significant among groups. There was no significant difference in the duration of postpartum magnesium sulfate therapy among groups, with the average duration of therapy 7.04 ± 8.17 hours. No eclamptic seizures occurred after magnesium discontinuation. Conclusion: Clinical criteria can be used successfully and safely to shorten the duration of postpartum magnesium sulfate administration for seizure prophylaxis in patients with pregnancy-related hypertensive disorders.