Tocolysis in the management of third trimester bleeding.

Fifteen patients were identified in a retrospective analysis of one institution's experience with the use of tocolysis in selected patients with an admission diagnosis of placenta previa or abruptio placentae. There were no fetal deaths after admission, and the two neonatal deaths were related to prematurity. Eight of the 15 patients receiving tocolysis had their pregnancies prolonged by 2 weeks or more, and there were no fetal or neonatal deaths in this group. Both neonatal deaths occurred in patients who underwent tocolysis but who gave birth within 1 day of admission. These data suggest the safety of tocolysis in preterm patients with the diagnosis of placenta previa or abruption who are bleeding. A prospective, randomized trial is required to evaluate whether tocolysis is superior to expectant management or to immediate delivery. The clinical difficulty in differentiating between these two diagnoses, despite liberal use of ultrasonography, is discussed.

Conservative management of placenta accreta. A case report.

Placenta accreta is a rare complication of pregnancy. Traditional therapy has centered upon total abdominal hysterectomy to prevent serious hemorrhagic and infectious sequelae. Conservative management, however, may preserve reproductive function without jeopardizing maternal welfare.

Indicators of perinatal asphyxia.

Creatinine phosphokinase and its isoenzymes (myocardial-specific MB and brain-specific BB) are elevated in the presence of specific tissue injury. The value of this serum marker as an objective indicator of perinatal asphyxia was studied. Forty-nine patients with gestational ages ranging from 36 to 42 weeks were prospectively studied. Patients who by interpretation of the fetal heart rate tracing alone were diagnosed as having fetal distress demonstrated significantly lower pH (p = 0.001) and base excess (p less than 0.0001) in umbilical venous blood. Umbilical venous cord MB (p less than 0.05) and BB (p less than 0.01) were increased in this group. Abnormal fetal heart rate patterns correlate well with acid-base abnormalities and elevated creatinine phosphokinase values. These tests may demonstrate more efficient and improved indicators of tissue injury and damage from perinatal asphyxia than clinical observation alone.

Magnesium sulfate and ritodrine hydrochloride: a randomized comparison.

The efficacy of magnesium sulfate was analyzed in relation to ritodrine hydrochloride. Patients presenting in preterm labor between 20 and 35 weeks' gestation were prospectively randomized. Tocolysis was achieved for more than 72 hours in 35 of 40 cases (88%) where magnesium sulfate was administered and 31 of 39 cases (79%) in which ritodrine hydrochloride was infused. Delay of greater than or equal to 7 days was achieved in 75% and 72% of cases, respectively. The mean dosage to achieve tocolysis was 4.5 gm/hr, in the magnesium sulfate group and 210.0 micrograms/hr in ritodrine hydrochloride-treated patients. The mean magnesium level to achieve tocolysis was 6.60 mg/dl. Side effects in the two groups were similar in number but less alarming in the magnesium sulfate group. Magnesium sulfate was found to be easy to administer and clinically efficacious. Its tocolytic action was found to be dose dependent and drug concentrations are easily determined. On the basis of this work and data from other investigators, magnesium sulfate should be used as the first line of tocolytic therapy with ritodrine hydrochloride as its pharmacologic backup.

Reacting appropriately to thrombocytopenia in pregnancy.

The lower limit of normal for the platelet count is considered to be 150,000/cu mm in both pregnant and nonpregnant normal adults. In the absence of preeclampsia, sepsis, drugs, or other apparent causes, the finding of asymptomatic mild thrombocytopenia in pregnant women is compatible with previously unrecognized immune thrombocytopenic purpura (ITP). Because of the risk of fetal/neonatal thrombocytopenia and the subsequent risk of neonatal intracranial hemorrhage in infants born of mothers with ITP, the optimal mode of delivery for an asymptomatic but thrombocytopenic mother is problematic. Conceivably, those gravidas with mild previously unrecognized thrombocytopenia may not have ITP and thus could be spared cesarean section. From the platelet counts of 730 antepartum patients, we found a mean value of 263,900/cu mm with a standard deviation of 66,000/cu mm, yielding 95% confidence limits of 134,500 to 393,300/cu mm. The distribution is statistically indistinguishable from a normal distribution. Of 26 asymptomatic thrombocytopenic patients with no hematologic history, none had infants with hemorrhage or platelet counts less than 100,000/cu mm. Only one patient subsequently had severe glucocorticoid-resistant thrombocytopenia requiring splenectomy several months after delivery. The remaining patients continue to be asymptomatic to date, with platelet counts greater than 100,000/cu mm. We suggest a plan for managing less than normal platelet counts in asymptomatic gravidas without a history of hematologic abnormality.

Antepartum fetal heart rate response to sound stimulation: the acoustic stimulation test.

The fetal heart rate acceleration response to an acoustic stimulation was compared to the traditional nonstress test in regard to pregnancy outcome, as reflected by the incidence of intrapartum fetal distress, meconium staining of the amniotic fluid, 1- and 5-minute Apgar scores, and perinatal mortality. Fetuses with spontaneous or sound-generated reactivity had comparably good outcomes with respect to all outcome measures investigated. Fetuses who lacked spontaneous or sound-stimulated reactivity had an increased risk for intrapartum fetal distress. The acoustic stimulation test is a safe and rapid test of fetoplacental sufficiency that appears to perform comparably to the nonstress test. The acoustic stimulation test significantly shortens total antepartum testing time and expense.

Isovolumetric partial exchange transfusion in the management of sickle cell disease in pregnancy. II. Simplified ambulatory technique.

A simple technique is presented for determining the volume of blood to be exchanged in an isovolumetric partial exchange transfusion in order to achieve a desired final hematocrit or desired final percentage of normal hemoglobin. Experience from 16 exchange transfusions in 10 obstetric patients is used to improve the estimate of specific blood volume and, hence, the accuracy of the technique. A detailed protocol for this simple outpatient procedure is presented.

Cryosurgery of the fetal ductus arteriosus.

The effects of cryosurgical treatment of the fetal ductus arteriosus (DA) on the structure and function of the neonatal DA are assessed for the first time. A cryosurgical probe, cooled with nitrous oxide, was used to freeze the wall of the DA in 5 fetal lambs. Six fetal lambs were used as control animals. After birth, all the cryosurgically treated lambs had a patent DA whereas all the control lambs had a closed DA. Only the cryosurgically treated group had these histologic findings: calcific deposits, necrosis, and focal ganglion cell necrosis in the outer one third to two thirds of the media with a decrease or loss of muscle cells and elastic fibers. This study suggests the feasibility of developing a cryosurgical approach for maintaining patency of the DA.

The dehydroepiandrosterone loading test. IV. Evaluation of clinical utility.

This report complements the previously described preliminary clinical evaluation of the dehydroepiandrosterone (DHEA) loading test (DLT) by presenting the results of 65 DLTs in 59 patients. In patients whose fetuses were suspected of being intrauterine growth retarded, a DHEA to estrogen conversion rate constant less than or equal to 3.0 x 10(-3) min(-1) was associated with a birth weight below the tenth percentile in 60% of the pregnancies, whereas a conversion rate constant above this threshold was not associated with the same degree of growth retardation. The DLT continues to qualify as an accurate predictor of pregnancy outcome as judged by birth weight. Although it seems to be too cumbersome to serve as a screening technique, the DLT will permit evaluation of the efficacy of various pregnancy interventions directed toward improvement of the intrauterine environment, such as bed rest, tocolysis, or antihypertensive medication.

Bacterial colonization of amniotic fluid in the presence of ruptured membranes.

Amniotic fluid (AF) was collected from 37 selected patients by amniocentesis, aspiration through a pressure catheter, or aspiration at the time of cesarean section. The unspun AF was examined directly by Gram stain for bacteria and white blood cells (WBC) and was cultured. Thirteen AF cultures were positive, defined as growth on primary plating media which corresponded to greater than 10(2) colony-forming units (CFU) per milliliter. Almost equal numbers of aerobic and anaerobic bacteria were isolated. The presence of bacteria, but not WBC, on Gram stain of AF correlated significantly with a positive culture, which indicated that microscopic examination of AF would usually predict the culture result. Growth of greater than 10(2) CFU/ml from AF was significantly associated with clinical chorioamnionitis, but colonization also was observed in five afebrile patients, four of whom were in premature labor. In patients delivered by cesarean section, bacteria on Gram stain and a positive culture from AF each were significantly correlated with postpartum endometritis.

The dehydroepiandrosterone loading test. III. A possible placental function test.

The dehydroepiandrosterone loading test (DLT) has been used in a small population of normal and high-risk obstetric patients, to date, in an attempt to develop a dynamic test of placental function. In spite of its limited applications, it has shown reliability in discriminating, with statistical significance, between high-risk pregnancies that result in normally grown, undistressed infants, and high-risk pregnancies that result in infants showing signs of placental insufficiency. The present report expands the study population by presenting our data on 40 loading tests performed in 37 high-risk and normal obstetric patients. Results of 19 of these DLT's have been previously reported and are included herein for statistical analysis. The DLT utilizes an excess substrate load of dehydroepiandrosterone to assess the maximum capability of the placenta to convert it to estrogen. Although our previous report did not show false positive or negative results in the conversion rates, the present results (40 DLT's) found two (2 out of 17) false positives (12%) and two (2 out of 19) false negatives (11%). The highly significant correlation between DLT result and pregnancy outcome seen previously was preserved. In addition, the data of another five DLT's in four patients are presented. This group includes a pregnancy with a fetus with multiple congenital malformations, two patients with intrauterine fetal death, and a nonpregnant woman. The results are not included in the statistical analysis, but discussion of these results has interesting pathophysiologic implications.

Effects of maternal isoxsuprine administration on preterm infants.

A retrospective study of all inborn infants at 26 to 35 weeks' gestational age delivered from August, 1976, through July, 1977, was undertaken to determine the effects on the neonate of maternal isoxsuprine therapy for premature labor. Mothers of 43 infants received ISX within 48 hours of delivery and mothers of 107 received no ISX. Hypocalcemia, hypoglycemia, evidence of ileus, hypotension, and neonatal death were all significantly more common in infants whose mothers received ISX. Hypotension and death occurred predominantly in infants of 26 to 31 weeks' gestation and in infants whose mothers developed hypotension or tachycardia during ISX infusion. The frequency of hypotension and death decreased as the time interval from the loading dose of ISX to delivery increased.

A physiologic model of the dehydroepiandrosterone to estrogen conversion system in the fetoplacental unit. I. Development.

A physiologic model of the dynamics of fetoplacental unit dehydroepiandrosterone (HDEA) to estrogen conversion is presented. A mathematical representation of this model is included. The model is used in Part II to determine the rate constant of DHEA to estrogen conversion and to successfully identify those fetuses in jeopardy from placental insufficiency within the population studied. This presentation permits critical comprehension of the model without extensive mathematical background.

A physiologic model of the dehydroepiandrosterone to estrogen conversion system in the fetoplacental unit. II. Preliminary clinical application--the dehydroepiandrosterone loading test.

A dehydroepiandrosterone (DHEA) loading test (DLT) is described. The results of 19 DHEA loading tests in as many third-trimester obstetric patients are presented. Analysis involves inspection of the raw data and the application of the physiologic model of the DHEA to estrogen conversion system described in the preceding paper (Part I). The DLT results show that within the population studied, the conversion rate of DHEA to estrogens is lower in patients with placental insufficiency than in normal patients (N = 5, p = 0.002) or in patients with various complications of pregnancy who deliver normally grown, undistressed infants (N = 6, p = 0.001). Routine clinical application must await more extensive evaluation to preclude the existence of forms of placental insufficiency not detected by this means, or normal states resulting in "false-positive" tests. These initial clinical results are intended primarily to demonstrate the potential clinical applicability of the physiologic model described in Part I.

Effect of exogenous dehydroepiandrosterone upon the fetoplacental biosynthesis of estrogens and its effect upon uterine blood flow in the term pregnant ewe.

The fetoplacental unit of the ewe is capable of increasing the biosynthesis of estrogens following the exogenous administration of DHEA to the fetus. The maximum concentrations of estrogens appeared approximately 30 minutes after the administration of DHEA. Uterine blood flow in the pregnant ewe increased approximately 90 minutes after the maximum concentrations of estrogens were noted. The administration of DHEA to the nonpregnant, ovariectomized ewe did not elicit estrogen biosynthesis or changes in uterine blood flow. Isotope experiments in the pregnant ewe demonstrated the incorporation of DHEA into urinary estradiol.