John D. Yeast

The effect of intrapartum epidural analgesia on nulliparous labor: A randomized, controlled, prospective trial

OBJECTIVE Our purpose was to determine the effect of epidural analgesia on nulliparous labor and delivery. STUDY DESIGN Normal term nulliparous women in early spontaneous labor were randomized to receive either narcotic or epidural analgesia. RESULTS When compared with the group receiving narcotic analgesia (n = 45), the group receiving epidural analgesia (n = 48) had a significant prolongation in the first and second stages of labor, an increased requirement for oxytocin augmentation, and a significant slowing in the rate of cervical dilatation. Epidural analgesia was associated with a significant increase in malposition (4.4% vs 18.8%, p < 0.05). Cesarean delivery occurred more frequently in the epidural group (2.2% vs 25%, p < 0.05), primarily related to an increase in cesarean section for dystocia (2.2% vs 16.7%, p < 0.05). CONCLUSIONS In a randomized, controlled, prospective trial epidural analgesia resulted in a significant prolongation in the first and second stages of labor and a significant increase in the frequency of cesarean delivery, primarily related to dystocia.

DHA supplementation and pregnancy outcomes

BACKGROUND Observational studies associate higher intakes of n-3 (omega-3) long-chain polyunsaturated fatty acids (LCPUFAs) during pregnancy with higher gestation duration and birth size. The results of randomized supplementation trials using various n-3 LCPUFA sources and amounts are mixed. OBJECTIVE We tested the hypothesis that 600 mg/d of the n-3 LCPUFA docosahexaenoic acid (DHA) can increase maternal and newborn DHA status, gestation duration, birth weight, and length. Safety was assessed. DESIGN This phase III, double-blind, randomized controlled trial was conducted between January 2006 and October 2011. Women (n = 350) consumed capsules (placebo, DHA) from <20 wk of gestation to birth. Blood (enrollment, birth, and cord) was analyzed for red blood cell (RBC) phospholipid DHA. The statistical analysis was intent-to-treat. RESULTS Most of the capsules were consumed (76% placebo; 78% DHA); the mean DHA intake for the treated group was 469 mg/d. In comparison with placebo, DHA supplementation resulted in higher maternal and cord RBC-phospholipid-DHA (2.6%; P < 0.001), longer gestation duration (2.9 d; P = 0.041), and greater birth weight (172 g; P = 0.004), length (0.7 cm; P = 0.022), and head circumference (0.5 cm; P = 0.012). In addition, the DHA group had fewer infants born at <34 wk of gestation (P = 0.025) and shorter hospital stays for infants born preterm (40.8 compared with 8.9 d; P = 0.026) than did the placebo group. No safety concerns were identified. CONCLUSIONS A supplement of 600 mg DHA/d in the last half of gestation resulted in overall greater gestation duration and infant size. A reduction in early preterm and very-low birth weight could be important clinical and public health outcomes of DHA supplementation. This trial was registered at clinicaltrials.gov as NCT00266825.

Changing patterns in regionalization of perinatal care and the impact on neonatal mortality

OBJECTIVE Our goal was to study changing patterns of low-birth-weight outcome over the past decade as deregionalized perinatal care has occurred. STUDY DESIGN Live births and neonatal mortality for two 5-year periods (1982 to 1986 vs 1990 to 1994) were calculated by hospital of delivery in the state of Missouri. Self-designated level of perinatal care was contrasted with number of deliveries and nursery census to evaluate outcome. Regression models were constructed to compare outcome between levels of care. RESULTS There has been a significant shift of deliveries into self-designated level II and III perinatal centers. However, this is largely a result of redesignation of care rather than an actual increase in acuity or census. The relative risk of neonatal mortality for very-low-birth-weight infants is 2.28 in level II centers compared with level III centers, and is unchanged (2.57) from 10 years earlier. Nearly 14% of very-low-birth-weight deliveries still occur at non-level III centers. CONCLUSION Changing patterns of perinatal regionalization have not improved outcome for inborn infants < 1500 gm except in level III centers. Attempts should be made to deliver very-low-birth-weight infants in level III centers.

The effect of maternal oxygen administration during the second stage of labor on umbilical cord blood gas values: A randomized controlled prospective trial

OBJECTIVE Our aim was to determine whether supplemental oxygen during the second stage of normal labor affects cord blood gas and cooximetry values. STUDY DESIGN Patients at term pregnancy were prospectively randomized to the control or treatment group at the onset of the second stage of labor. The treatment group received 10 L/min oxygen by face mask, which result in a mean fractional inspired oxygen concentration of 0.81. RESULTS There were 86 patients randomized into the study. In the oxygen group there were significantly more cord arterial pH values < 7.20 (9/41 vs 2/44, p < 0.05). The control group was compared with two subgroups of patients receiving oxygen: those receiving oxygen therapy for < or = 10 minutes and those receiving oxygen for > 10 minutes. Analysis of variance demonstrated significant differences (7.285 +/- 0.058, 7.312 +/- 0.056, 7.237 +/- 0.064; F test 8.3, p = 0.0005). Among several independent variables, regression analysis demonstrated that only duration of oxygen therapy had a significant inverse relation to cord arterial pH (F test = 15.6, p = 0.0002). CONCLUSIONS Prolonged oxygen treatment during the second stage of normal labor resulted in a deterioration of cord blood gas values at birth.

The risk of pulmonary edema and colloid osmotic pressure changes during magnesium sulfate infusion

OBJECTIVES The purposes of this study were to evaluate the effect of magnesium sulfate therapy on colloid osmotic pressure and to determine whether changes in colloid osmotic pressure increased the risk of pulmonary edema. STUDY DESIGN During a 1-year time period 294 patients received parenteral magnesium sulfate for the treatment of preterm labor or preeclampsia. Both changes in colloid osmotic pressure and magnesium sulfate values and their relationship to clinical outcome parameters were analyzed. RESULTS Serum magnesium levels were similar for both patients with preeclampsia and patients with preterm labor. Pulmonary edema developed in only four patients, all of whom had preeclampsia and low colloid osmotic pressure values. CONCLUSIONS This study demonstrated that parenteral magnesium sulfate therapy does not cause significant changes in colloid osmotic pressure values until nearly 48 hours of continuous therapy.

PRETERM PREMATURE RUPTURE OF THE MEMBRANES BEFORE VIABILITY

Although relatively uncommon, VPPROM remains a devastating complication of pregnancy. Current management options offer some hope of improved survival, but morbidity and mortality remain high. Counseling the patient and family following this diagnosis is challenging, and often requires input from both perinatal and neonatal staff. For those patients choosing expectant management who then reach viability, tertiary care should be considered to improve survival risks.

Epidural analgesia in labor and cesarean delivery for dystocia

Published studies assessing the effect of epidural analgesia in nulliparous labor on the frequency of cesarean delivery for dystocia are reviewed. There are at least four retrospective studies and two prospective studies that suggest that epidural analgesia may increase the risk of cesarean delivery for dystocia in first labors. The potential for epidural to increase the frequency of cesarean delivery for dystocia is likely influenced by multiple variables including parity, cervical dilatation at epidural placement, technique of epidural placement, management of epidural during labor, and the obstetrical management of labor after placement of epidural analgesia. Two studies suggest that delaying placement of the epidural until 5 cm of cervical dilatation or greater may reduce the risk of cesarean birth. Epidural is safe and may be a superior labor analgesic when compared with narcotics. However, patients should be informed that epidural analgesia may increase the risk of cesarean birth in first labors.

The use of continuous insulin infusion for the peripartum management of pregnant diabetic women

Sixteen pregnant diabetic patients near term were maintained on a regimen of continuous insulin infusion during the peripartum period. Blood glucose remained in the range of 75 to 150 mg. per deciliter, with insulin infusion rates between 0.25 and 2.00 U. per hour. Following delivery the infusion was continued through the first postpartum day or until oral intake was tolerated and subcutaneous long-acting insulin could be given. Sliding scale regimens were unnecessary; insulin dosage for discharge was easily determined; and the metabolic care of these patients was greatly simplified. Neonatal hypoglycemia in the 17 infants delivered of these diabetic patients was not entirely eliminated despite euglycemia in the mothers.

Placental Alpha Microglobulin-1 Compared With Fetal Fibronectin to Predict Preterm Delivery in Symptomatic Women

OBJECTIVE To compare the rapid bedside test for placental α microglobulin-1 with the instrumented fetal fibronectin test for prediction of imminent spontaneous preterm delivery among women with symptoms of preterm labor. METHODS We conducted a prospective observational study on pregnant women with signs or symptoms suggestive of preterm labor between 24 and 35 weeks of gestation with intact membranes and cervical dilatation less than 3 cm. Participants were prospectively enrolled at 15 U.S. academic and community centers. Placental α microglobulin-1 samples did not require a speculum examination. Health care providers were blinded to placental α microglobulin-1 results. Fetal fibronectin samples were collected through speculum examination per manufacturer requirements and sent to a certified laboratory for testing using a cutoff of 50 ng/mL. The coprimary endpoints were positive predictive value (PPV) superiority and negative predictive value (NPV) noninferiority of placental α microglobulin-1 compared with fetal fibronectin for the prediction of spontaneous preterm birth within 7 days and within 14 days. RESULTS Of 796 women included in the study cohort, 711 (89.3%) had both placental α microglobulin-1 and fetal fibronectin results and valid delivery outcomes available for analysis. The overall rate of preterm birth was 2.4% (17/711) within 7 days of testing and 4.2% (30/711) within 14 days of testing with respective rates of spontaneous preterm birth of 1.3% (9/703) and 2.9% (20/701). Fetal fibronectin was detected in 15.5% (110/711), and placental α microglobulin-1 was detected in 2.4% (17/711). The PPVs for spontaneous preterm delivery within 7 days or less among singleton gestations (n=13) for placental α microglobulin-1 and fetal fibronectin were 23.1% (3/13) and 4.3% (4/94), respectively (P<.025 for superiority). The NPVs were 99.5% (619/622) and 99.6% (539/541) for placental α microglobulin-1 and fetal fibronectin, respectively (P<.001 for noninferiority). CONCLUSION Although placental α microglobulin-1 performed the same as fetal fibronectin in ruling out spontaneous preterm delivery among symptomatic women, it demonstrated statistical superiority in predicting it.

Fetal anemia as a response to prophylactic platelet transfusion in the management of alloimmune thrombocytopenia

The antenatal management of alloimmune thrombocytopenia (ATP) frequently requires fetal blood sampling and prophylactic platelet transfusion. A recent case of ATP complicated by associated red blood cell alloimmunization demonstrated severe hemolysis apparently as a result of ABO incompatibility from transfused platelets.