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S N Caritis

Publications and source records attributed to S N Caritis.

At least 73 records · Page 4Linked to original sources
PubMed1983

Treatment of preterm labour. A review of the therapeutic options.

Preterm delivery accounts for a major proportion of perinatal deaths. The cause of preterm labour is usually not known, but in most instances, maintaining the fetus in utero appears to be preferred to allowing preterm delivery. Numerous pharmacological agents have been utilised to inhibit preterm labour, but none has proven to be ideal. Currently, the beta-adrenoceptor stimulants such as ritodrine, terbutaline, isoxsuprine, salbutamol and fenoterol provide the best combination of safety and efficacy. However, because of their potential adverse effects, adequate maternal and fetal surveillance needs to be maintained throughout their administration. Magnesium sulphate, although probably not as effective as other labour-inhibiting drugs, is an appropriate choice when the beta-adrenoceptor stimulants are either contraindicated or poorly tolerated. Other drugs such as the prostaglandin inhibitors, diazoxide or the calcium antagonists are also potent labour-inhibitors, but further controlled studies are required to evaluate the risks associated with their use. Ethanol has been supplanted by the beta-adrenoceptor stimulants and is unlikely to be used in the future.

Adrenergic beta-Agonists↗
PubMed1982

Portal venous blood flow distribution to liver and ductus venosus in newborn lambs.

Changes in the distribution of portal venous blood flow to the left and right lobes of the liver and through the ductus venosus were determined from before birth through 9 days of age in 25 chronically catheterized fetal and newborn lambs. Blood flow distribution was calculated by means of the radionuclide-labeled microsphere technique. With umbilical cord clamping portal venous blood flow distribution to the right lobe of the liver decreased when compared to that in the term fetus; distribution to the left lobe and ductus venosus increased. More than 50% of portal blood flow was shunted through the ductus venosus during the first hour after birth. Ductus venosus shunts of at least 25% of total portal blood flow were noted in half the lambs between the second and sixth days of life. Portal venous distribution to the right lobe was inversely related to the fraction of portal blood flow shunted through the ductus venosus. The ratio of right lobe weight to total liver weight was significantly correlated with the ratio of right lobe flow to total liver flow (r = 0.73; P less than 0.001). The conclusion is that large and persistent ductus venosus shunts are normal during the first postnatal week in lambs.

Animals↗
PubMed1982

A comparison of terbutaline and ethanol in the treatment of preterm labor.

Ninety-two women in preterm labor were randomly assigned to either terbutaline or ethanol. In women with intact membranes, terbutaline was significantly more effective than ethanol in preventing progressive cervical dilation during the first 36 hours of treatment while betamethasone was given to the mother. Additionally, pregnancy was maintained significantly longer in women with intact membranes who were treated with terbutaline (15 +/- 4 days) rather than with ethanol (10 +/- 3 days). However, only 18% of women in each treatment group maintained their pregnancy beyond 36 weeks' gestation. In women with ruptured membranes and cervical dilation less than 4 cm, terbutaline was significantly better than ethanol in maintaining pregnancy for a minimum of 36 hours. Serious maternal side effects were not observed with terbutaline or ethanol, although a majority of women also received betamethasone. Neither drug caused serious adverse neonatal effects.

Apgar Score↗
PubMed1981

Comparison of continuous transcutaneous Po2 measurement with intermittent arterial Po2 determinations in fetal lambs.

This study determined the validity of transcutaneous Po2 (tcPo2) versus Pao2 determinations in the sheep fetus. In 7 fetal lambs catheters were placed in the carotid artery and the trachea, and ECG leads and a tcPo2 electrode were attached. Intermittently determined Pao2 values were compared to continuously recorded tcPo2 values. Fetal tcPo2 values ranging from 12 to 29 mmHg were achieved by changing the gas mixture the ewe breathed or by inflation of a balloon catheter in the maternal aorta. Transcutaneous Po2 correlated strongly with Pao2 (r = .91). These studies indicate that the tcPo2 electrode precisely and accurately reflects Pao2 in the fetal lamb. Limitations of tcPo2 measurements regarding prolonged attachment of the electrode to the fetal skin as well as fetal skin tolerance to the heat of the electrode have been identified. With this electrode the changes in oxygen tension can be compared with changes in fetal cardiovascular variables, eg, heart rate, blood pressure, and ECG, for a better understanding of the effects of hypoxemia on the fetus.

Animals↗
PubMed1980

Effect of adrenergic agonists on progesterone production by human placental cells in culture.

Human placental cells maintained were used to determine the direct effect of beta-adrenergic agonists on progesterone accumulation by the placenta. In five studies, when either of the beta-adrenergic receptor agonists, terbutaline or isoproterenol, 1.5 micrograms/ml, was incubated for 24 hours with the placental cells, significantly more progesterone was present in the culture medium than in the medium of matched controls. Compared with the medium of matched controls, progesterone in medium increased 36 +/- 6% (mean +/- SE) when cells were treated with terbutaline and 38 +/- 7% when cells were treated with isoproterenol. In two dose-response studies with terbutaline, a minimal dose of 0.15 micrograms/ml was required to significantly increase progesterone in medium compared with that in matched controls. In three studies, propranolol at a concentration of 1.5 micrograms/ml completely blocked the stimulatory effect of 1.5 micrograms/ml of terbutaline.

Cells, Cultured↗
PubMed1980

Umbilical venous blood flow and its distribution before and during autonomic blockade in fetal lambs.

In nine chronically catheterized fetal lambs (120 to 135 days; term 147 days) umbilical venous blood flow and its distribution were measured by the radionuclide-labeled microsphere technique before and during autonomic blockade with atropine (0.20 to 0.25 mg/kg; seven studies) or phentolamine (0.10 to 0.12 mg/kg; six studies). Atropine significnatly increased mean fetal heart rate (182 to 207 beats/min), descending aortic blood pressure (49 to 55 mm Hg), and umbilical venous blood flow (210 to 239 ml/min/kg fetus), without changing umbilical venous blood pressure. Phentolamine decreased mean descending aortic pressure (48 to 45 mm Hg), but did not affect heart rate, umbilical venous blood pressure, or umbilical venous blood flow. Neither atropine nor phentolamine altered the distribution of umbilical venous blood flow to the ductus venosus, the liver, or the other fetal organs. These data indicate that the cholinergic nervous system only indirectly affects the basal umbilical venous blood flow in the near-term fetal lamb. This effect is small and is secondary to associated changes in heart rate and arterial blood pressure. Neither the cholinergic nor the alpha-adrenergic systems influence the basal distribution of umbilical venous blood flow.

Animals↗
PubMed1980

Effects of electronic fetal heart rate monitoring on perinatal outcome and obstetric practices.

Perinatal outcome and obstetric practices during 1970 and 1977 were compared. None of the 6,740 fetuses delivered with birth weights of 1,000 gm or greater in 1970 had electronic fetal monitoring (EFM). In 1977, 5,987 of 8,174 fetuses delivered had EFM (72.7%). High-risk factors were significantly more frequent in the pregnant patient population in 1977. The incidence of intrapartum stillbirths and severe birth asphyxia was significantly lower in 1977. These reductions remained significant when corrected for changes in obstetric practices other than EFM as well as for changes in patient population. The neonatal death rate was not significantly changed. The primary cesarean section rate increased from 4.4% to 10.1%, mostly because of a greater number of cesarean sections done for failure to progress in labor and breech presentation. Only 15% of the overall increase in cesarean section rate was because of a greater frequency of the indication of fetal distress. The incidence of severe birth asphyxia was the same among the unmonitored patients in 1970 and 1977. In 1977, however, the monitored patients had a significantly lower incidence of severe birth asphyxia than the unmonitored patients.

Asphyxia Neonatorum↗
PubMed1980

Statistical fluctuations in heart rate variability indices.

Short-term variability in the fetal heart rate (FHR) is believed to be associated with fetal well-being, and a number of quantitative indices of variability have been proposed. Before using such an index, its sampling properties must be well understood so that apparent changes in "variability" can be confidently attributed to biological origins rather than statistical sampling fluctuations. We have compared the sampling properties of two representative variability indices on computer-synthesized "random" FHR patterns. Both indices demonstrated statistical fluctuations which decreased with increasing sample size; the coefficient of variation of a single index value is approximately Formula: see text with N being the number of cardiac cycles observed in practice, if changes in variability are to be detected with reasonable confidence, heart rate observations of several minutes will generally be required.

Computers↗
PubMed1980

Induction of labor with low-dose prostaglandin F2 alpha and oxytocin.

A double-blind study was performed in 50 patients with the use of low-dose intravenous oxytocin or PGF2 alpha for the induction of labor for elective or high-risk indications. Both agents were equally effective for the induction of labor. No major complications were encountered with either drug in mother or infant. The ability to induce labor with relatively small, infrequently increased doses of either inducing agent was an unexpected finding.

Double-Blind Method↗
PubMed1980

Fetal acid-base state following spinal or epidural anesthesia for cesarean section.

The authors compared fetal acid-base state and maternal blood pressure response in 111 women undergoing repeat cesarean section with either epidural or spinal anesthesia. Fetal umbilical acidemia (umbilical venous pH less than 7.25 or umbilical arterial pH less than 7.20) was more commonly observed following spinal anesthesia with a preanesthetic fluid load of 500 to 999 ml (20% of cases) than with epidural anesthesia (4% of cases. P > .05, chi 2). The incidence of fetal acidemia following spinal anesthesia was similar to that following epidural anesthesia when 1000 to 1500 ml of fluid was infused prior to spinal anesthesia. The maximum reduction in systolic blood pressure following spinal anesthesia was not related to preanesthetic fluid load; however, in cases of severe hypotension the hypotensive episode was shorter and easier to treat when the preanesthetic fluid load was 1000 to 1500 ml rather than 500 to 999 ml. These data suggest that women receiving spinal anesthesia for repeat cesarean section should be given an intravenous fluid load of 1 liter or more.

Acid-Base Equilibrium↗
PubMed1979

Pharmacologic inhibition of preterm labor.

Preterm labor is responsible for a majority of cases of perinatal morbidity and deaths. Prevention of preterm labor is not usually possible; thus pharmacologic treatment is the only recourse available. Numerous agents have been used to treat preterm labor, but none has proved to be superior. This report reviews the current information available about the pharmacology of labor-inhibiting drugs and discusses the clinical approach to the management of preterm labor.

Adrenergic beta-Agonists↗
PubMed1978

Effects of dexamethasone on leukocyte counts in pregnant sheep and fetal lambs.

In adult nonpregnant animals and human beings, glucocorticosteroids increase circulating leukocytes (predominantly neutrophils) and decrease lymphocytes, monocytes, and eosinophils. We were interested in studying effects of glucocorticoids on leukocyte counts during pregnancy to determine any differences between responses in the nonpregnant and pregnant states. After general anesthesia was administered, we placed catheters in a carotid artery and a jugular vein in pregnant sheep and in fetal lambs. Six days after surgery, we administered dexamethasone intravenously to the mother (0.2 mg. per kilogram) or to the fetus (0.06 mg. per kilogram) and obtained maternal and fetal jugular venous blood samples immediately before (control) and 3, 6, 12, 24, 48, and 72 hours after steroid injection. Administration of dexamethasone to the mother significantly increased total leukocyte and neutrophil counts (leukocytes per cubic millimeter blood) and decreased lymphocyte and eosinophil counts, but it did not change monocyte counts. Leukocyte counts returned to control values within 48 hours. Administration of dexamsthasone to the fetus rapidly increased total leukocyte and neutrophil counts, decreased monocyte and eosinophil counts, and had not effect on lymphocyte counts. Fetal leukocyte counts returned to control values by 24 hours after dexamethasone injection. Our results suggest that maternal and fetal leukocytes can respond to glucocorticoids as they do in the adult nonpregnant state.

Animals↗
PubMed1978

Lecithin/sphingomyelin ratio in amniotic fluid and its value for the prediction of neonatal respiratory distress syndrome in pregnant diabetic women.

In 101 diabetic pregnant women (Classes A through D) 146 determinations of the lecithin/sphingomyelin (L/S) ratio were carried out. Gestational ages were verified by serial fetal cephalometry. No L/S ratios of more than 2.0 were found before 34-1/2 weeks' gestation; however, in 42 per cent of patients the L/S ratio was below 2.0 at 36 weeks' gestation or later. Respiratory distress syndrome (RDS) was found in 16 neonates of women with L/S ratios of 2.0 or higher; however, RDS incidence varied depending on the mode of delivery. Abdominal delivery was performed before 37 weeks' gestation in 19 patients with L/S ratios of 2.0 or higher and resulted in neonates with RDS in 41 per cent of cases. Vaginal delivery was accomplished below 37 weeks' gestation in 10 patients with L/S ratios of 2.0 or higher and no subsequent neonatal RDS was observed. After 37 weeks' gestation neonatal RDS is rare, irrespective of mode of delivery. The data presented suggest that similar numerical values of the L/S ratio at different gestational ages have a different predictive value for the occurrence of neonatal RDS.

Amniotic Fluid↗
PubMed1978

Sinusoidal fetal heart rate pattern following intrauterine fetal transfusion.

Two patients with severe rhesus isoimmunization had sinusoidal fetal heart rate patterns following intrauterine fetal transfusion. A consistent temporal relationship between fetal transfusion and sinusoidal fetal heart rate pattern was observed. Survival of a fetus who had a sinusoidal fetal heart rate pattern after each of three transfusions suggests that this pattern may not be ominous when observed transiently after fetal transfusion.

Adult↗
PubMed1977

Effect of betamethasone on analysis of amniotic fluid in the rhesus-sensitized pregnancy.

Betamethasone was administered to six rhesus-sensitized pregnant women carrying seven fetuses in an attempt to accelerate fetal pulmonary maturation. A reduction in optical density of amniotic fluid at 450 mmu was observed in all cases following steroid therapy; however, only minimal changes were noted in the lecithin-sphingomyelin ratio. The implications of these findings for the management of rhesus-sensitized pregnancies are discussed.

Amniocentesis↗