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R K Creasy

Publications and source records attributed to R K Creasy.

At least 37 records · Page 2Linked to original sources
PubMed1990

Prevention of preterm birth: clinical opinion.

Spontaneous preterm delivery continues to be the most significant problem facing clinicians as we enter the 1990s. Prevention of preterm labor still awaits needed improvements in prediction. At present, most preterm birth prevention programs are based upon the early recognition of preterm labor followed by prompt tocolysis. Programs based upon patient education and support, daily contact by trained nurses, intermittent cervical assessment, and daily sampling of uterine activity have been associated with a decrease in preterm birth. The exact contribution of each component to reduce preterm birth remains to be defined and, at present, a combination of the components is still suggested.

Female↗
PubMed1989

Routine umbilical cord blood gas determinations?

Between 1986 and 1988, 1924 term nulliparous patients with spontaneous onset of labor were studied to assess the importance of obtaining umbilical cord blood gas levels on all deliveries. The umbilical cord arterial and venous pH values (expressed as mean +/- 2 SD) were 7.24 +/- 0.14 (n = 1694) and 7.32 +/- 0.12 (n = 1820), respectively. The incidence of newborn depression (1- or 5-minute Apgar score less than 7) was 14.1%; of these depressed newborns, the incidence of normal umbilical cord arterial pH values (greater than or equal to -2 SD) was 77.8%. Of the vigorous newborns, there was a 2.1% incidence of umbilical cord arterial blood acidemia. Umbilical cord arterial blood acidemia in vigorous newborns was not highly predictive of specific morbidity in the immediate newborn period. Regression analysis demonstrated the umbilical cord arterial pH to correlate best with the Apgar scores when compared with all other arterial or venous blood gas measurements. We reached the following conclusions: (1) that obtaining cord arterial pH values in vigorous newborns should be considered since the values will provide objective documentation or normal fetal acid base balance in 98% of infants. (2) Only a cord arterial pH determination is recommended since it reflects fetal or newborn status more accurately than all other measurements. Additional measurements increase the likelihood of abnormal results and do not contribute to neonatal management. (3) An umbilical cord blood pH value is extremely useful in ruling out the diagnosis of birth asphyxia in the depressed newborn.

Acid-Base Equilibrium↗
PubMed1989

The effect of magnesium sulfate tocolysis on the fetal biophysical profile.

The biophysical profile has proved to be a valuable tool for the assessment of fetal well-being, independent of gestational age. Magnesium sulfate is commonly used as a tocolytic agent, yet relatively little is known about its effects on the biophysical activities of the fetus. To investigate the effects of magnesium sulfate on the biophysical profile, we performed serial studies on patients who received tocolytic therapy with this agent because of preterm labor. A total of 16 women with 22 fetuses at 26 to 34 weeks' gestation in spontaneous preterm labor were studied. An initial biophysical profile was performed at the time of admission, and a second examination was performed when maternal serum magnesium levels reached 6 to 8 mg/dl. On admission all fetuses had reactive nonstress test results and 21 of 22 (95%) demonstrated sustained fetal breathing movements. With magnesium sulfate tocolysis, 50% of fetuses had nonreactive nonstress test results, and only 4 of 22 (18%) demonstrated sustained fetal breathing movements. Fetal tone, gross body movements, and amniotic fluid volume were found to be unaffected by magnesium sulfate tocolysis.

Adult↗
PubMed1989

Evaluation of a risk-scoring system for prediction of preterm labor.

A scoring system was used prospectively to screen 7329 patients for risk of preterm labor over a 6-year period. When 15.8% of patients (1156 of 7329) were scored as high risk, sensitivity was 42.4% (multiparas, 55.2%, nulliparas, 29.8%) and positive predictive value was 22.8%. The incidence of preterm labor increased with increasing risk score; gestational age at delivery was negatively correlated with risk score. Analysis of individual factors revealed that more than half were not of predictive value in the population under investigation. A simplification of the system, defining 12 of the factors as major (high risk) and six as minor (2 or more indicates high risk) yielded a high risk group of 14.1%, sensitivity of 41.0%, and positive predictive value of 24.6%. Thus, although risk scoring does predict a substantial proportion of patients with preterm labor, its sensitivity is less than ideal. No advantage was gained with a larger and more complex system. Planning for preterm birth prevention programs should include recognition of the limitations of risk scoring, consideration of simplified systems, and investigation of additional biochemical or biophysical screening methods.

Female↗
PubMed1988

Maternal brain death during pregnancy. Medical and ethical issues.

We present in detail a case of a 27-year-old primigravida who was maintained in a brain-dead state for nine weeks. An apparently normal and healthy male infant weighing 1440 g was delivered. The newborn did well and was found to be growing and developing normally at 18 months of age. Although the technical aspects of prolonged life support are demanding and the economic costs are very high (+217,784), there are ample ethical arguments justifying the separation of brain death and somatic death and the maintenance of the brain-dead mother so that her unborn fetus can develop and mature.

Adult↗
PubMed1988

Intramuscular versus intravenous ritodrine hydrochloride for preterm labor management.

A prospective, interinstitutional comparative trial was undertaken to examine the efficacy, safety, and pharmacodynamics of different administration routes of ritodrine hydrochloride for the management of preterm labor. Forty-five subjects between 20 and 36 weeks' gestation received either intravenous (n = 24) or intramuscular (n = 21) therapy. Successful tocolysis occurred in 14 of 21 (67%) patients in the group treated intramuscularly and in 16 of 24 (67%) patients in the group treated intravenously. A greater mean dose (8.6 versus 3.3 mg/hour) and a higher mean serum concentration (38.9 versus 24.7 micrograms/ml) were needed to achieve successful tocolysis in the intravenous group as compared with the intramuscular group. Patients who did not respond to tocolytic therapy in both groups had levels of ritodrine in the blood either equivalent to or greater than those of subjects who were successfully treated. Analysis of ritodrine levels in the successfully treated intramuscular group demonstrated significant differences in blood levels depending on muscle group used. These differences can be at least partially attributed to higher mean doses administered to patients receiving vastus lateralis injections as compared with those receiving gluteal muscle injections. The results suggest that intramuscular administration of ritodrine is an efficacious and safe route of drug delivery. Additional studies are needed to better define dose-response curves for the intramuscular administration of ritodrine hydrochloride.

Buttocks↗
PubMed1988

Prevention of preterm birth.

Prevention of prematurity is the principal goal of all obstetric care. Although conquest of preterm births may yet be a distant goal that will require substantial improvements in understanding the pathophysiology of PTD, interim progress is possible. Increased attention to prematurity prevention as the focus of prenatal care can have an impact now, without introducing unproven or hazardous techniques or medication. Reproductive health care aimed at the prevention and elimination of social, demographic, and medical correlates of prematurity can yield results if obstetricians take the lead in educating both patients and society at large about the hazards of prematurity. Progress is more likely if a global strategy is used in all pregnancies as reported by Papiernik et al., Meis et al., and Herron et al. These studies have similar messages of hope and caution: All reported benefit in decreasing the frequency of preterm births, all required substantial and widespread patient and provider education, and all required a sustained effort before any effect was noted. Main et al. showed that these programs are not likely to produce a quick turnaround in PTD rates in all populations; progress will be slow. Reports of limited success or even failure should not result in abandonment of the goal, but rather in renewed and imaginative efforts toward it.

Bed Rest↗
PubMed1988

California North Coast Preterm Birth Prevention project.

A demonstration project aimed at reducing the incidence of preterm birth in a rural population of Northern California was conducted using risk assessment, patient education, and education for providers as interventions. We compared 1914 preintervention deliveries with 7382 births during the intervention period. Although the percentage of preterm labor patients eligible for tocolysis was 34% greater during the intervention period than during the preintervention period, and the percentage of preterm labor patients who achieved term gestation was 53% greater in the intervention period, the overall rate of spontaneous preterm delivery in the population did not differ significantly in the two periods.

Birth Rate↗
PubMed1987

Evaluation of the weekly cervical examination in a preterm birth prevention program.

The efficacy of regular cervical examinations in detecting preterm labor, as well as possible risks, was studied for 133 preterm labor patients who had received regular cervical examinations as part of a preterm birth prevention program. When compared to all other patients experiencing preterm labor during the study period, the rates of preterm premature rupture of the membranes, chorioamnionitis, and postpartum endomyometritis were not increased. For 95 patients with preterm labor within 7 days of a routine cervical examination, labor onset was not temporally associated with the preceding examination. Preterm labor was diagnosed in 18 asymptomatic patients (18.2%) when the weekly examination revealed cervical change. Routine cervical exams, therefore, did not increase morbidity, and for some patients identified preterm labor before symptoms appeared.

Cervix Uteri↗
PubMed1986

Preterm labor: its diagnosis and management.

Preterm labor and delivery remain a significant problem in contemporary obstetric practice. Although the exact cause remains unclear, it is most likely to be multifactorial in nature. No satisfactory screening tool or marker currently exists to firmly establish the diagnosis of impending labor. However, epidemiologic and historical variables associated with preterm delivery show some promise in this regard and are currently being evaluated in preterm prevention programs. Appropriate management of preterm labor mandates early recognition of subtle signs and symptoms; successful therapy is dependent on this issue. The approach to the clinical management of the patient in preterm labor used at our institution is described. Therapy with beta-adrenergic receptor agonists is currently the recommended pharmacologic treatment of this disorder. A review of other tocolytic agents and their usefulness in the management of preterm labor are presented.

Adolescent↗
PubMed1986

Short-term neonatal morbidity associated with prematurity and the effect of a prematurity prevention program on expected incidence of morbidity.

With recent advances in neonatal medicine, the risk of mortality for premature newborns has been markedly reduced. Attention has shifted to the morbidity associated with preterm delivery. Consideration of anticipated neonatal morbidity at a particular gestational age plays an important part in the decision of whether or not to treat preterm labor. We have assessed eight indices of short-term morbidity in 170 liveborn infants delivered between 26 and 35 completed weeks of gestation and calculated the gestational age-specific rates of each measure of morbidity. Five measures of short-term morbidity were significantly reduced by extending the gestation from 34 to 35 weeks. To illustrate the effect of prolonged pregnancy on the incidence of short-term neonatal morbidity, the actual incidence of morbidity from a group of preterm labor patients who were part of a preterm birth prevention program was compared to the anticipated incidence of these same morbidity factors has birth occurred when preterm labor was first diagnosed. There was a significant decrease in the number of observed, as opposed to anticipated, neonatal deaths and in morbidity occurrences in four of the six factors tested. Implications for considering short-term neonatal morbidity in the decision to initiate treatment for preterm labor after 33 weeks gestation are discussed.

California↗
PubMed1986

Endodermal sinus tumor of the ovary associated with pregnancy.

The association of endodermal sinus tumor of the ovary with pregnancy is a rare event. Reported is a patient with stage Ic endodermal sinus tumor diagnosed in the 25th week of gestation. She received two cycles of combination chemotherapy consisting of vinblastine, bleomycin, and cisplatin, and delivered a healthy male infant by cesarean section at 32 weeks' gestation. She subsequently completed three more cycles of chemotherapy and remains alive and well. This is the first reported case of a patient with endodermal sinus tumor treated with combination chemotherapy during pregnancy that had a successful outcome for both mother and infant. The literature concerning the association of endodermal sinus tumor and pregnancy and the use of chemotherapy during pregnancy is reviewed.

Adult↗
PubMed1984

Preterm delivery is not predicted by serial plasma estradiol or progesterone concentration measurements.

Previous studies suggest that plasma estradiol-17 beta and progesterone concentration values differ between patients who deliver before term and those who deliver at term. To determine if these values would aid in preterm delivery risk prediction, we measured plasma estradiol-17 beta and progesterone concentrations serially in 90 patients at high risk for preterm delivery. Measurements from 17 patients who developed documented preterm labor and/or were delivered before term were compared to the tenth and ninetieth percentiles of 42 patients who were delivered at term. The sensitivity of these measurements to predict preterm delivery was very low. Also, the mean plasma estradiol-17 beta and progesterone concentrations in patients with preterm labor who had term deliveries and in patients with preterm labor that progressed to preterm delivery were not different from each other or from patients delivering at term. No change in plasma estradiol-17 beta or progesterone concentration was noted preceding labor. We conclude that serial measurements of plasma estradiol-17 beta and progesterone concentrations do not improve preterm delivery risk prediction.

Adolescent↗
PubMed1984

Mammary blood flow regulation in the nursing rabbit.

Cardiac output and mammary blood flow distribution prior to and after suckling were studied in 10 nursing rabbits by means of radionuclide-labeled microspheres. Suckling was followed by a 5.8% rise in cardiac output and a 20.4% rise in mammary blood flow. Determinations of intraglandular blood flow distribution have shown that there was a 43% increase in blood flow to the glands suckled from as compared to a 22.7% rise to the contralateral untouched glands and a 4.9% rise in the remainder of untouched glands. The conclusion is that a local mechanism may be involved in the regulation of mammary blood flow in the nursing rabbit.

Animals↗
PubMed1984

Ultrasonographic determination of qualitative amniotic fluid volume in intrauterine growth retardation: reassessment of the 1 cm rule.

To assess the relative diagnostic efficacy of the "1 cm sign" for qualitative amniotic fluid volume determination in the prenatal evaluation of intrauterine growth retardation, 125 pregnancies resulting in small-for-gestational age infants were studied in a retrospective fashion. Qualitative amniotic fluid volume was designated as normal if at least one pocket of amniotic fluid measuring 1 cm in broadest diameter was identified. Of the 125 pregnancies with delivery of small-for-gestational age infants, only five would have been correctly predicted prenatally with qualitative amniotic fluid volume used as the sole criterion for intrauterine growth retardation. When this criterion was applied to a defined subset of 52 of these patients with last scans 0 to 15 days prior to delivery, only four cases would have been accurately predicted as having intrauterine growth retardation.

Amniotic Fluid↗
PubMed1984

Responses of the growth-retarded fetus to acute hypoxemia.

Growth retardation in the human fetus associated with maternal cardiovascular disease is frequently accompanied by birth asphyxia and perinatal mortality. We have investigated the cardiovascular responses to acute hypoxemia in the fetal lamb with growth retardation secondary to embolization of the uteroplacental vascular bed. In the basal period, fetal arterial P02 and umbilical perfusion were significantly lower, and perfusion of the adrenal glands, brain, and heart was significantly higher, in embolized than in control fetal lambs. During imposed acute hypoxemia there was preferential perfusion of vital organs, the adrenal glands, brain, and heart in control and embolized fetuses. This preferential perfusion to the vital organs during hypoxemia was significantly more pronounced in embolized animals. Because of the increased compensation during acute hypoxemia, as reflected by the increased preferential perfusion of vital organs, the growth-retarded fetuses would probably decompensate sooner if the hypoxemia was prolonged.

Acute Disease↗
PubMed1984

Prevention of preterm delivery. The important role of early recognition.

Perinatal deaths can be decreased most effectively by reducing the incidence of preterm delivery. Therapy with a tocolytic agent, such as ritodrine ( Yutopar ), can be of significant benefit if applied to patients in whom preterm labor is correctly diagnosed and has not advanced beyond the early stages. Identification of the patient at risk, intensive education and surveillance of such patients, and education of hospital and clinic staff can extend the application and success of labor-inhibiting therapy.

Administration, Oral↗