Bobby C. Howard

Vagal nerve stimulator use during pregnancy for treatment of refractory seizure disorder

BACKGROUND: In patients with medically refractory seizures, vagal nerve stimulation is becoming an increasingly common adjunctive therapy. Although its safety and efficacy have been proven in the general population, little is known about its use during pregnancy. CASE: A 19-year-old primigravid woman presented during the first trimester for routine prenatal care. She had a past medical history significant for generalized tonic–clonic seizure disorder since childhood. Multiple medical regimens had failed, and a vagal nerve stimulator was implanted approximately 2 months before conception. The patient continued to take phenytoin, with improved seizure control. She had a term spontaneous delivery complicated by mild preeclampsia. CONCLUSION: Adjunctive treatment of medically refractory seizures with a vagal nerve stimulator is a viable option during pregnancy.

Transplacental passage of antimicrobial paraben preservatives.

Parabens are widely used preservatives suspected of being endocrine disruptors, with implications for human growth and development. The most common paraben found in consumer products is methylparaben. To date, no study has examined whether these substances cross the human placenta. A total of 100 study subjects (50 mother–child pairs) were enrolled at two medical institutions, serving primarily African-American and Caucasian women, respectively. A maternal blood sample was drawn on admission and a paired cord blood sample was obtained at delivery. Of the 50 mothers, 47 (94%) showed methylparaben in their blood (mean level 20.41 ng/l), and 47 in cords bloods (mean level 36.54 ng/l). There were 45 mother–child pairs where methylparaben was found in both samples. Of these, the fetal level was higher than the maternal level in 23 (51%). For butylparaben, only 4 mothers (8%) showed detectable levels (mean 40.54 ng/l), whereas 8 cord blood samples (16%) were positive (mean 32.5 ng/l). African-American mothers and infants showed higher prevalence of detectable levels (P=0.017). Methylparaben and butylparaben demonstrate transplacental passage. Additional studies are needed to examine potential differences in exposure by geography and demographics, what products are used by pregnant women that contain these preservatives, as well as any potential long-term effects in the growth and development of exposed children.

Transplacental passage of vancomycin from mother to neonate

OBJECTIVE The objective of the study was to analyze a large number of patients receiving vancomycin chemoprophylaxis and evaluate the maternal and neonatal cord blood levels at the time of delivery. STUDY DESIGN Every mother who entered labor with a positive group B streptococcal culture and a high-risk penicillin allergy with resistance to clindamycin or unknown sensitivity was consented to participate in the study. In the initial phase of the study, patients received the standard intravenous dose of 1 g every 12 hours. Based on the results, this was changed to a dosing of 15 mg/kg every 12 hours in the second phase and then further modified to 20 mg/kg every 8 hours in the third phase. Maternal and cord blood vancomycin levels were obtained at delivery and evaluated. RESULTS A total of 55 patients consented to participate in the study, with 31 in phase I, 12 in phase II, and 12 in phase III. For the standard-dosing phase I group, only 32% of maternal and 9% of cord blood samples were therapeutic at delivery. For phase II, 50% of maternal and 33% of cord blood values were therapeutic; however, in phase III, 83% of mothers and neonates had therapeutic levels at the time of delivery. CONCLUSION With standard dosing, only 9% of neonates have therapeutic vancomycin levels at delivery. By using a regimen of 20 mg/kg intravenous every 8 hours (maximum individual dose 2 g), the newborn therapeutic level increases above 80%. The pharmacological pattern shows that transplacental passage occurs with fetal levels equaling maternal levels, but transplacental transport is somewhat slow in both directions.

Fire in labor and delivery: Simulation case scenario

DEMOGRAPHICS Case Title: Fire in Labor and Delivery: Simulation Case Scenario. Simulation Developers: OB/GYN Department Chairman and Maternal Fetal Medicine Director, Anesthesia Attending, Perinatal Nurse Educator, OB/GYN Simulation Director, Hospital Safety Director, Labor and Delivery Nurse Manager. Dates of Development: August to November 2009. Target Audience: All OB/GYN faculty, all OB/GYN residents, all Labor and Delivery nursing staff, all Anesthesia residents and attendings, medical students on Anesthesia or OB/GYN rotations.

The use of prostaglandin E1 in peripartum patients with asthma

OBJECTIVE Prostaglandin E₁ (PGE₁) is commonly used in obstetric practice for labor induction and cervical ripening and in treating postpartum hemorrhage; however, its use in pregnant asthmatic patients has not been studied to date. The package insert states there is an unknown causal side effect for dyspnea and bronchospasm. Other pharmacological publications have stated that bronchoconstriction may occur with the use of PGE₁. The study objective was to examine peripartum pregnant asthmatic patients who received prostaglandin E₁. STUDY DESIGN Every patient who was administered PGE₁ from January 2010 through December 2013 was prospectively recorded. The charts were retrospectively reviewed. Peripartum patients with asthma were identified and further analyzed for any evidence of an asthma exacerbation following administration of the drug. RESULTS A total of 234 of 2629 patients (8.9%) who received PGE₁ were identified as having asthma. None of the patients had any evidence of an asthma exacerbation (0 of 234; 95% confidence interval, 0-0.017). Of the 234 patients, 104 (44%) had active asthma and were receiving daily medication, and the remaining 130 patients had a medical history of asthma for which they used an inhaler on an as-needed basis. A total of 98 patients (42%) received greater than 400 μg of total dose. A post hoc statistical assessment was performed, and the study was sufficiently powered to detect any clinically meaningful increase in asthma exacerbation with PGE₁ usage, if such a risk existed. CONCLUSION Based on the 95% confidence interval of these data, the maximum risk for an asthma exacerbation following the use of prostaglandin E₁ is less than 2%. Although all medications administered to asthmatic patients in the peripartum period should be carefully selected, this information supports the use of prostaglandin E₁ in obstetric patients with asthma, if clinically indicated.

Chronic Opiate Use in Pregnancy and Newborn Head Circumference

OBJECTIVE The aim of the study is to evaluate whether chronic opiate use in pregnancy affects newborn head circumference (HC). STUDY DESIGN All newborns from January 1, 2010, to June 30, 2012, admitted to the neonatal intensive care unit for treatment of neonatal abstinence syndrome were prospectively collected. The demographic, obstetrical, neonatal, and perinatal ultrasound data were retrospectively obtained. A gestational age-matched control was used for comparison purposes. RESULTS Of 332 neonates admitted for the treatment of neonatal abstinence syndrome, 98 (29.5%) had a HC ≤ 10th percentile for gestational age that was significantly increased when compared with controls (p < 0.001). Of these 98, 25 had a HC ≤ 3rd percentile. Of the case population, 141 had an ultrasound in the perinatal unit within 10 days of birth. A HC < 5th percentile was found in 38.3% of cases of which 74% were ≤ 10th percentile postdelivery. The ultrasound femur and humerus length measurements were also < 5th percentile in 36.2 and 28.9%, respectively. CONCLUSION Chronic opiate use in pregnancy appears to increase the risk for a HC ≤ 10th percentile and ≤ 3rd percentile when compared with controls. From ultrasound findings, femur and humerus lengths also appear to be shortened suggesting a possible effect on bone growth.

Postprandial Walking Reduces Glucose Levels in Women with Gestational Diabetes Mellitus

The purpose of this study was to investigate blood glucose changes, as measured by a continuous glucose monitoring system, that occur in women with gestational diabetes mellitus (GDM) following an acute bout of moderate-intensity walking after consuming a high-carbohydrate/low-fat meal. This study found that moderate-intensity walking induced greater postprandial glucose control compared with sedentary activity and it appears that moderate-intensity activity may be used to reduce postprandial glucose levels in women with GDM.

Incidence of maternal tachycardia during the second stage of labor: a prospective observational cohort study

Abstract Objective: To our knowledge, this is the largest prospective study reporting on maternal heart rate (MHR) levels in laboring women (30 patients), and maternal tachycardia that is a potential risk factor in fetal monitoring confusion. Our objective was to analyze a large population of contiguous laboring patients and to assess the MHR levels attained during the second stage. Methods: We performed a prospective study that analyzed MHR levels of second-stage laboring patients evaluating numerous predisposing maternal conditions. Univariate and stepwise multivariate logistic regression analysis were performed. Results: A total of 1105 contiguous patients were analyzed and 33.9% had a sustained MHR ≥100; 18.8% had an MHR ≥110; and 9.1% had an MHR ≥120. Multivariate analysis of all potential predisposing maternal conditions did not reveal any specific variable as uniformly significant for predicting maternal tachycardia across all levels of analysis. Conclusions: The incidence of maternal tachycardia in the second stage of labor is common. We recommend that if the MHR is ≥100 during labor, the simultaneous maternal and fetal heart rate (FHR) monitoring will be used to minimize the potential for fetal monitoring confusion and risking poor fetal outcome if the fetus is in distress.

Accuracy of the lamellar body count in amniotic fluid contaminated by meconium.

Abstract Objective: To determine whether meconium-contaminated amniotic fluid falsely elevates the lamellar body count in fetal lung maturity testing. Methods: Thirty mothers undergoing amniocentesis for fetal lung maturity testing were prospectively consented. A 2 mL portion of the patient’s sample was mixed with a 10% meconium solution and the meconium-stained sample was then run in tandem with the patient’s sample used in clinical management. Pure meconium samples without amniotic fluid were also run through the cell counter for analysis. Results: Following meconium contamination, the lamellar body count value increased in 67% of the cases, decreased in 23% and remained the same in 10%. There were 13 test results that had “immature” values in the uncontaminated patient management sample group and nine of these (69%) became elevated to a “mature” level (a false elevation) following the addition of meconium. All of the 10 pure liquid meconium samples devoid of amniotic fluid processed by the cell counter identified and quantified some particle the size of platelets. Conclusions: The lamellar body count test result is not reliable in meconium-stained amniotic fluid specimens. There is some unknown particle found in meconium that is the size of platelets/lamellar bodies that can falsely elevate the test result. Currently, the only reliable fetal lung maturity test in meconium-stained amniotic fluid is the presence of phosphatidylglycerol.