Biomedical subjects

B K Rinehart

Publications and source records attributed to B K Rinehart.

At least 19 recordsLinked to original sources

PubMed2003

Dexamethasone compared with betamethasone for glucocorticoid treatment of postpartum HELLP syndrome.

OBJECTIVES: To compare the efficacy of dexamethasone and betamethasone to ameliorate the course of postpartum hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. METHODS: A prospective, mixed randomized/non-randomized clinical investigation of patients with postpartum HELLP syndrome. Treatment with either dexamethasone or betamethasone was continued until there was evidence of disease recovery. RESULTS: Baseline characteristics of both the dexamethasone (n=18) and betamethasone (n=18) groups were similar. Although the time to discharge from the obstetrical recovery room was not statistically significant between groups, reduction in mean arterial blood pressure was more pronounced in the dexamethasone group as compared with the betamethasone group (-15.3+/-1.4 mmHg vs. -7.5+/-1.4 mmHg, respectively, P<0.01). Patients in the dexamethasone group required less antihypertensive treatment than the betamethasone group (6% vs. 50%, P=0.01) and also had a decreased need for readmission to the obstetrical recovery room (0% vs. 22%, P=0.03). CONCLUSION: This investigation supports the use of dexamethasone as the superior glucocorticoid to use for patients with postpartum HELLP syndrome.

Adrenal Cortex Hormones↗

PubMed2002

Repeat postpartum magnesium sulfate administration for seizure prophylaxis: is there a patient profile predictive of need for additional therapy?

OBJECTIVE: To profile patients with hypertensive disorders of pregnancy who require reinstitution of magnesium sulfate therapy for disease exacerbation. STUDY DESIGN: A prospective clinical trial enrolling gravidas with pre-eclampsia. The length of postpartum magnesium sulfate seizure prophylaxis was determined by individual patient characteristics. Patients with exacerbation of their disease after discontinuation of magnesium sulfate received a second course of magnesium sulfate lasting 24 h. RESULTS: Of a total of 503 patients, 38 (7.6%) required reinstitution of postpartum magnesium sulfate therapy for an additional 24-h period. Patients with chronic hypertension complicated by superimposed pre-eclampsia were most likely to require further therapy (11/61, 18.0%), when compared with other hypertensive disorders. Additionally, patients who required reinstitution of magnesium therapy had significantly shorter gestations (32.4 +/- 4.2 weeks versus 36.3 +/- 4.2 weeks, respectively; p < 0.001), and higher mean arterial pressure during the initial magnesium course (113.2 +/- 11.2 versus 105.6 +/- 11.3 mmHg; p < 0.001). CONCLUSION: Patients with chronic hypertension complicated by superimposed pre-eclampsia, patients delivered prior to 35 weeks' gestation and patients requiring a longer initial magnesium prophylaxis are at higher risk for the need of reinstitution of seizure prophylaxis postpartum.

Anticonvulsants↗

PubMed2001

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

OBJECTIVE: To determine whether intra-uterine 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 microg lipopolysaccharide endotoxin, or 50 microg 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 microg) 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.

Animals↗

PubMed2001

The myth of transient hypertension: descriptor or disease process?

The objective of this study is to describe the incidence of transient hypertension and to evaluate if transient hypertension is associated with increased maternal or fetal morbidity as compared to other hypertensive disorders of pregnancy and normotensive controls. Data were collected from all deliveries at the University of Mississippi Medical Center from July 1, 1996 through January 1, 1997. Patients were grouped according to ACOG criteria for pregnancy induced hypertension. Specific maternal and fetal morbidities were compared among the groups and controls. There were 1489 deliveries during the study period. Nearly 30% of patients met the criteria for transient hypertension. There were no significant differences between patients with transient hypertension and controls in regard to maternal and fetal outcomes. Transient hypertension occurs more often than expected, however, it appears to be of limited clinical significance.

Adult↗

PubMed2001

Pregnancy outcome in women with preterm labor symptoms without cervical change.

OBJECTIVE: This study was undertaken to determine pregnancy outcome in women who have preterm labor symptoms without cervical change according to fetal fibronectin status. STUDY DESIGN: Patients who were examined at the obstetric emergency department with symptoms of preterm labor but without cervical change underwent fetal fibronectin collection. Pregnancy outcome and fetal fibronectin results were analyzed after delivery. RESULTS: Of the 235 patients sampled, 20% (n = 48) had positive fetal fibronectin results. The mean +/- SD gestational age at delivery was lower in women with positive fetal fibronectin results (34.2 +/- 4.1 vs 37.7 +/- 2.3 weeks; P <.001); these women were more likely to deliver preterm as a result of preterm labor than women with other obstetric indications (46% vs 19%; P <.001). Infants born to these women demonstrated lower birth weight (2317 +/- 895 g vs 2877 +/- 557 g; P =.003), were more likely to be admitted to the neonatal intensive care unit (42% vs 14%; P <.001), and were more likely to die in the neonatal period (11% vs 0%; P <.001). CONCLUSION: Patients with symptoms of preterm labor but without cervical change who have negative fetal fibronectin results are less likely to deliver preterm. Therefore in women with symptoms but without cervical change fetal fibronectin should be considered for risk assessment.

Adult↗

PubMed2001

Change in platelet count predicts eventual maternal outcome with syndrome of hemolysis, elevated liver enzymes and low platelet count.

OBJECTIVE: To profile the rates of change for platelets and lactate dehydrogenase (LDH) in patients with the syndrome of hemolysis, elevated liver enzymes and low platelet count (HELLP) to reflect and possibly predict disease severity. METHODS: Serial determinations of the platelet count and serum LDH were analyzed retrospectively for 545 patients with HELLP syndrome and 94 severely pre-eclamptic patients. A repeated measures (mixed model) analysis of variance (ANOVA) was utilized to estimate the rates of change for LDH and platelets in each group. RESULTS: Patients who developed class 1 or 2 HELLP syndrome exhibited a rapid deterioration in platelet count of 45-50,000/microl per day compared to 30,000/microl per day for class 3 and non-HELLP severe pre-eclampsia. For LDH, values increased at a rate of approximately 1400 IU/l per day, 600 IU/l per day, 300 IU/l per day and 200 IU/l per day for patients with classes 1, 2 and 3 and for non-HELLP severe pre-eclampsia, respectively. CONCLUSION: The rate of change of platelets and LDH appeared to correlate well with eventual syndrome severity and this can be used to enhance patient assessment beyond the value of a single test for either laboratory parameter.

Adult↗

PubMed2000

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.

Adult↗

PubMed2000

Single umbilical artery is associated with an increased incidence of structural and chromosomal anomalies and growth restriction.

The objective to characterize neonatal outcome associated with ultrasonographic identification of a single umbilical artery. Pregnancies diagnosed with single umbilical artery antenatally were identified. All prenatal/antenatal and pediatric records were reviewed for maternal demographics, associated anomalies, karyotypic analysis, pregnancy complications, and neonatal outcome. Twenty-seven pregnancies complicated by fetal single umbilical artery were identified. Of the 27 pregnancies, 5 (18.5%) underwent pregnancy termination and 1 (3.7%) experienced fetal demise. Of the 21 liveborn infants, 4 (19%) died within the first year of life. Sixty-seven percent of fetuses had an associated structural anomaly. Sixteen of the 27 pregnancies underwent amniocentesis and 7 of these were chromosomally abnormal. All of the karyotypically abnormal fetuses had a structural defect in addition to the single umbilical artery. Of the six fetuses without any associated structural or chromosomal anomalies, three (50%) demonstrated growth restriction. Single umbilical artery is relatively rare finding. When a single umbilical artery is identified, a vigilant search for associated anomalies should be undertaken. Pregnancies identified as having fetuses with associated structural anomalies should be offered amniocentesis. Pregnancies with isolated single umbilical artery should be carefully monitored for evidence of fetal growth restriction.

Adult↗

PubMed2000

Intrauterine endotoxin infusion in rat pregnancy induces preterm delivery and increases placental prostaglandin F2alpha metabolite levels.

OBJECTIVE: This study was designed to examine the effects of intrauterine endotoxin (lipopolysaccharide) on rat pregnancy. STUDY DESIGN: Pregnant Sprague-Dawley rats (N = 26) were implanted with uterine catheters on day 15 or 16 of a 22-day gestation. Animals were randomly assigned to receive either lipopolysaccharide (25 or 50 microg) or sodium chloride solution (1 mL) on day 17 and then were either sacrificed on day 19 or observed until delivery. Placentas were harvested at the time of death, homogenates were prepared, and prostaglandin F(2)(alpha) metabolite levels were determined by means of radioimmunoassay. Data were analyzed by analysis of variance, Student-Newman-Keuls, and Mann-Whitney tests. RESULTS: Lipopolysaccharide-treated groups (25 and 50 microg) displayed a shorter interval to delivery (mean +/- SE, 82 +/- 13 and 63 +/- 8 hours, respectively) than control animals (117 +/- 3 hours). Pups of lipopolysaccharide-treated (25 and 50 microg) female animals had lower live birth weights (4.92 +/- 0.01 and 5.12 +/- 0. 24 g, respectively) compared with control animals (6.04 +/- 0.07 g). Placental homogenates from lipopolysaccharide-treated female animals contained higher levels of prostaglandin F(2)(alpha) metabolite (1567 +/- 64 and 1475 +/- 59 pg/mL) than those from sodium chloride solution-infused control animals (804 +/- 68 pg/mL). CONCLUSION: Bacterial products induce the preterm delivery of low-birth-weight pups in rats, possibly by increasing local prostaglandin biosynthesis.

Animals↗

PubMed2000

Lack of utility of standard labor curves in the prediction of progression during labor induction.

OBJECTIVE: This study was undertaken to determine whether patients undergoing labor induction can be reliably evaluated by means of standard labor assessment curves. STUDY DESIGN: In this retrospective chart review of 123 patients who underwent cervical ripening and induction of labor, Friedman's standard labor curves were used for comparison. Statistical analysis was performed with the Student t test. RESULTS: Nulliparous and parous patients undergoing cervical ripening spent more time in active-phase labor than standard expectations of labor progression would indicate (12.7 +/- 7.8 vs 5. 9 +/- 3.4 hours for nulliparous women, P <.001; 7.9 +/- 6.4 vs 2.5 +/- 1.5 hours for parous women, P <.001). Nulliparous and parous patients who were delivered vaginally spent more time in active labor than did their respective standard historical control populations (10.3 +/- 8.0 vs 5.9 +/- 3.4 hours for nulliparous women, P <.001; 7.0 +/- 6.0 vs 2.5 +/- 1.5 hours for parous women, P <. 001). CONCLUSION: Standard methods for the evaluation of labor adequacy and prediction of the likelihood of vaginal delivery may not apply to patients undergoing cervical ripening.

Adult↗

PubMed2000

A prospective, randomized, controlled trial of high and low maintenance doses of magnesium sulfate for acute tocolysis.

OBJECTIVE: This study was undertaken to compare a high-dose protocol for magnesium sulfate tocolytic therapy with a low-dose regimen with respect to time needed to achieve tocolysis. STUDY DESIGN: Patients between 24 and 34 weeks' gestation with preterm labor were included. Patients with ruptured membranes or nonreassuring fetal assessments were excluded. Gravid women received a 4-g loading dose of magnesium sulfate and were prospectively randomly assigned to receive a maintenance dose of 2 or 5 g/h. RESULTS: The median times to tocolysis were 120 minutes (semi-interquartile range, 30 minutes) in the low-dose group and 90 minutes (semi-interquartile range, 28 minutes) in the high-dose group (P <.001). CONCLUSION: Patients treated with a higher maintenance dose of magnesium sulfate had a higher frequency of side effects; however, tocolysis was achieved more rapidly and they required shorter admissions to the labor and delivery unit without increased maternal or neonatal morbidity.

Adult↗

PubMed2000

Determination of amniotic fluid volume in twin pregnancies: ultrasonographic evaluation versus operator estimation.

OBJECTIVE: We sought to determine the accuracy of amniotic fluid volume estimation (visually) in diamniotic twin pregnancy versus ultrasonography techniques. STUDY DESIGN: In this prospective study the volume of each sac in 23 sets of diamniotic twin pregnancies was subjectively and objectively estimated by a second-year obstetric resident, nurse sonographer, maternal-fetal medicine fellow, and maternal-fetal medicine staff. The actual volume was confirmed by amniocentesis and a dye-dilution technique. RESULTS: There was no difference in the total number of correct estimates of volume by level of operator experience (P =.98), ultrasonography technique (P =.87), or combined subjective versus objective correct estimates (P =.87). Identification of low volume was not different among the four evaluators (P =.48), but the percentage of correct estimates was poor (7%-29%). The 2-diameter pocket was a better predictor of oligohydramnios (57%) than the amniotic fluid index or the largest vertical pocket (12.5%; P =.002). CONCLUSION: The extremes of volume (low or high) are poorly identified by the subjective or objective assessment of volume.

Adult↗

PubMed2000

Increasing maternal weight: a risk factor for preeclampsia/eclampsia but apparently not for HELLP syndrome.

BACKGROUND: Maternal obesity is a risk factor for severe preeclampsia. We sought to ascertain whether a similar relationship exists between maternal weight and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets) as an atypical form of severe preeclampsia. METHODS: In this retrospective investigation, 434 patients with HELLP syndrome were assigned to one of four study groups according to maternal weight and were analyzed in relation to selected maternal and perinatal data reflective of disease severity. RESULTS: We found no significant associations between maternal weight and parameters of HELLP syndrome severity, race, delivery mode, gestational age, or perinatal outcome. Significantly associated with increasing maternal weight were maternal age, parity, admission mean arterial pressure, peak peripartum systolic blood pressures, concurrent essential hypertension, and the interval between admission and delivery. Inversely associated were eclampsia and the interval between delivery and discharge. CONCLUSIONS: Severity and complications attendant with HELLP syndrome appear unrelated to maternal weight. Paradoxically, eclampsia occurs most commonly in the lighter gravida with HELLP syndrome.

Adult↗

PubMed2000

Leukocytosis is proportional to HELLP syndrome severity: evidence for an inflammatory form of preeclampsia.

BACKGROUND: We investigated the possibility that HELLP syndrome is in part a systemic inflammatory response. METHODS: We evaluated total white blood cell (WBC) counts of all patients with severe preeclampsia with and without HELLP syndrome admitted to our hospital between 1995 and 1997. Patients were grouped by diagnosis and timing of platelet nadir. Analysis of variance and regression analysis were used for data analysis. RESULTS: Of 177 patients, 91 had HELLP syndrome, and 86 had severe preeclampsia alone. The WBC counts were significantly higher in patients with HELLP syndrome (12.5 +/- .442 x 10(9)/L) than in patients with severe preeclampsia (10.3 +/- .288 x 10(9)/L). Regression analysis showed that platelet counts varied inversely with WBC counts. Also, patients with class I HELLP syndrome had significantly higher WBC counts than patients with other classes of HELLP syndrome. CONCLUSION: The finding of an association between increasing leukocytosis and worsening thrombocytopenia early in the course of HELLP syndrome supports the hypothesis that it may represent an inflammatory process.

Analysis of Variance↗

PubMed1999

Neonatal sepsis and death caused by resistant Escherichia coli: possible consequences of extended maternal ampicillin administration.

OBJECTIVE: Our goal was to evaluate the relationship between neonatal death caused by sepsis associated with ampicillin-resistant organisms and length of antibiotic exposure. STUDY DESIGN: All neonatal deaths from culture-positive sepsis over a 3-year period were examined. Infants who were delivered at either the University of Mississippi Medical Center or at Saint Barnabas Medical Center at >/=24 weeks' gestation and died within 7 days of life were included. Information on the organism causing sepsis and its sensitivities was collected, and the number of doses of ampicillin administered to the mother before delivery was determined. RESULTS: Of the 78 neonatal deaths, 35 met the inclusion criteria. There were 8 cases of sepsis from ampicillin-resistant Escherichia coli and 27 cases caused by other organisms. There was a statistically significant difference between the mean number of doses of ampicillin received by the ampicillin-resistant Escherichia coli group (17.6 +/- 5.5) compared with the other organisms group (4.9 +/- 3.6) (P <.001). CONCLUSION: A relationship exists between neonatal death caused by ampicillin-resistant Escherichia coli and prolonged antepartum exposure to ampicillin.

Ampicillin↗

PubMed1999

Multiple courses of betamethasone to enhance fetal lung maturation do not suppress neonatal adrenal response.

OBJECTIVE: Our purpose was to evaluate the neonatal adrenal gland by provocative testing in neonates of mothers who had received multiple courses of betamethasone to enhance fetal lung maturity. STUDY DESIGN: Infants of mothers who had received >/=3 courses of betamethasone for fetal lung maturation were enrolled in the study. Twenty-four hours after delivery a baseline serum cortisol concentration was obtained. A synthetic adrenocorticotropic hormone (Cortrosyn) was administered (0.25 mg/1.73 m2). Two hours later a second serum cortisol concentration was obtained. An increase in serum cortisol in response to Cortrosyn was considered a positive test result. Nominal data were compared by means of the Student t test. RESULTS: There were 9 infants enrolled in the study. The mean number of betamethasone treatment cycles was 4.8 +/- 1.09. The mean baseline cortisol level was 2.23 +/- 0.52 microgram/dL, and the mean post-adrenocorticotropic hormone cortisol level was 9.86 +/- 1.70 microgram/dL. All neonates had a positive adrenocorticotropic hormone test result. Stepwise linear regression showed no association between the number of courses of betamethasone treatment cycles and the post-adrenocorticotropic hormone cortisol concentration. CONCLUSION: Multiple weekly treatment cycles of betamethasone for fetal lung maturity administered between 24 and 34 weeks' gestation do not appear to cause adrenal suppression.

Adrenal Glands↗

PubMed1999

The spectrum of severe preeclampsia: comparative analysis by HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome classification.

OBJECTIVE: This study was undertaken to explore the spectrum of maternal disease with a triple classification system of HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome and compare these classes with severe preeclampsia without HELLP syndrome. STUDY DESIGN: In this retrospective analytic study the pregnancies of 777 patients with class 1, 2, or 3 HELLP syndrome were compared and contrasted with those of 193 women with severe preeclampsia but without HELLP syndrome. RESULTS: Eclampsia, epigastric pain, nausea and vomiting, significant proteinuria, major maternal morbidity, and stillbirth increased as HELLP syndrome worsened from class 3 to class 1. In contrast, headache and diastolic hypertension were more common among the significantly heavier patients with severe preeclampsia without HELLP syndrome. Approximately half of pregnancies complicated by class 1 HELLP syndrome exhibited significant maternal morbidity, compared with only 11% of those complicated by severe preeclampsia without HELLP syndrome. Although a significant trend was apparent in increasing levels of lactate dehydrogenase, aspartate aminotransferase, and uric acid as HELLP syndrome worsened, there was considerable variation within groups. CONCLUSION: Laboratory and clinical indices of disease severity in patients with severe preeclampsia or eclampsia generally were highest with class 1 HELLP syndrome and were lowest when HELLP syndrome was absent. Class 3 HELLP syndrome is considered a clinically significant transitional group.

Aspartate Aminotransferases↗

PubMed1999

Early risk assessment of severe preeclampsia: admission battery of symptoms and laboratory tests to predict likelihood of subsequent significant maternal morbidity.

OBJECTIVE: This study was undertaken to investigate the utility of an admission battery of findings and laboratory data in the discrimination of patients with severe preeclampsia with or without HELLP (hemolysis, elevated liver enzyme levels, and low platelet count) syndrome at high risk for development of significant maternal morbidity. STUDY DESIGN: The clinical and laboratory findings at hospital admission for 970 patients with severe preeclampsia with or without HELLP syndrome were studied retrospectively to develop parameters associated with low, moderate, and high risks for the subsequent development of significant maternal morbidity involving the hematologic and coagulation, cardiopulmonary, and hepatorenal systems. RESULTS: Nausea and vomiting and epigastric pain are independent risk factors for complicated severe preeclampsia. Results of a panel of tests with values including lactate dehydrogenase level >1400 IU/L, aspartate aminotransferase level >150 IU/L, alanine aminotransferase level >100 IU/L, uric acid level >7.8 mg/dL, serum creatinine level >1.0 mg/dL, and 4+ urinary protein by dipstick can be used to discriminate the patient at high risk for significant maternal morbidity. Concentrations of lactate dehydrogenase, aspartate aminotransferase, and uric acid above these cut points have the strongest predictive value and are risk additive with worsening thrombocytopenia. CONCLUSION: The presence of nausea and vomiting, epigastric pain, or both in association with admission laboratory values that are in excess of the cutoffs for lactate dehydrogenase, aspartate aminotransferase, and uric acid concentrations or for all 6 tests is predictive of high risk of morbidity for the patient with severe preeclampsia. These factors are independent of and additive with the rising maternal risk associated with decreasing platelet count.

Alanine Transaminase↗