The role of bacterial vaginosis and vaginal bacteria in amniotic fluid infection in women in preterm labor with intact fetal membranes.
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Amniotic Fluid↗
Biomedical subjects
T R Easterling
Publications and source records attributed to T R Easterling.
Effect of changes in maternal age, parity, and birth weight distribution on primary cesarean delivery rates.
OBJECTIVE: To examine the effect of maternal age on cesarean delivery risk and to quantify the impact of demographic changes since 1970 on primary cesarean delivery rates. DESIGN: A cohort study. SETTING: Nonfederal short-stay hospitals in Washington State. PARTICIPANTS: All women who delivered live singletons with linked birth certificate and hospital discharge data from 1987 through 1990. MAIN OUTCOME MEASURES: Maternal age-, birth weight-, and parity-specific primary cesarean delivery rates, Mantel-Haenszel relative risk estimates for primary cesarean delivery by 5-year age category stratified by parity, and direct standardization of 1987 through 1990 primary cesarean rates to 1970 Washington State maternal age, birth weight, and parity distribution. RESULTS: Primary cesarean rates ranged from 3.2% for multiparous teenage women who delivered infants weighing 3500 g through 3999 g to 58.9% for primiparous women 40 years of age or older who delivered infants weighing 4000 g or more. After adjustment, the risk of cesarean delivery increased with each 5-year age increment among women 20 years of age or older. We estimated that if the maternal age, parity, and birth weight distribution from 1987 through 1990 were identical to what existed in 1970, Washington State's primary cesarean rate from 1987 through 1990 would have been 12.2%, compared with the observed rate of 14.8%. CONCLUSION: The lower adjusted primary cesarean rate reflects the demographic changes in the childbearing population, which may be responsible for 18% of the 1987 through 1990 cesarean delivery rates. These findings suggest the importance of using maternal age-, birth weight-, and parity-specific primary cesarean delivery rates to compare populations and study temporal trends.
Adolescent↗
Acute effects of sublingual nitroglycerin on hepatic blood flow in healthy volunteers.
Duplex sonography was used to assess the effects on hepatic blood flow after administering 0.6 mg nitroglycerin (NTG) sublingually to ten healthy volunteers. The study was a randomized, placebo-controlled, cross-over study in which subjects were studied on three separate occasions. Each visit involved administering either placebo or NTG followed by estimation of blood flow through a particular branch of the hepatic artery, portal vein, and hepatic vein every minute for 15 minutes after NTG and placebo administration. Two hours later, subjects were crossed over to the other treatment and the same vessel branch was again examined for 15 minutes. Total blood flow increased 7% in the portal vein and 27% in the hepatic vein during NTG treatment, but did not change significantly in the hepatic artery. Vascular resistance was increased in the hepatic artery and decreased in the portal and hepatic veins after NTG. Qualitatively, flow changed dramatically in the hepatic vein after NTG with the disappearance of normal retrograde flow. The results indicate that nitroglycerin effects hepatic blood flow through the portal and hepatic veins with a decrease in vascular resistance in the portal and hepatic veins and an increase in resistance in the hepatic artery.
Administration, Sublingual↗
The hemodynamic effects of isometric exercise during late normal pregnancy.
OBJECTIVE: Our study was designed to evaluate the hemodynamic effects of isometric exercise in late normal pregnancy. STUDY DESIGN: Study subjects were 10 healthy pregnant volunteers with uncomplicated singleton gestations between 25 and 36 weeks. Doppler methods were used to derive cardiac output, total peripheral resistance, and stroke volume before, during, and after a defined protocol of lower extremity isometric exercise. Hemodynamics and blood pressure were evaluated and compared. RESULTS: Mean arterial blood pressure and total peripheral resistance increased during the performance of isometric effort (mean blood pressure +/- SD was 78.9 +/- 7.3 to 97.5 +/- 8.6 mm Hg; total peripheral resistance +/- SD was 924 +/- 148 to 1153 +/- 18.3 dyne.sec.cm-5; p < 0.002 and p < 0.001, respectively). Cardiac output remained unchanged throughout the study period. CONCLUSION: In advanced normal pregnancy isometric exercise increases the mean arterial blood pressure by raising the total peripheral resistance.
Blood Pressure↗
Breech extraction of low-birth-weight second twins: can cesarean section be justified?
The outcomes of 54 breech-extracted second twins weighing between 750 and 2000 gm were compared with the outcomes of their siblings and of 43 sets of twins delivered by cesarean section for malpresentation. Vaginally delivered first twins had fewer days of mechanical ventilation and oxygen therapy than their breech-extracted siblings (p = 0.004). There were no significant differences in any measures of neonatal outcome when breech-extracted twins were compared with second twins delivered by cesarean section. We conclude that routine cesarean section is not justified for nonvertex second twins expected to weigh less than 2000 gm.
Breech Presentation↗
Effect of orthostatic stress on umbilical Doppler waveforms in normal and hypertensive pregnancies.
OBJECTIVE: Our study examined the effects of orthostatic stress and maternal hemodynamics on umbilical systolic/diastolic ratios in normal and hypertensive pregnancies. STUDY DESIGN: Eighteen normal and 20 hypertensive third-trimester pregnancies were examined in the left lateral recumbent, sitting, and standing positions. Measurements included umbilical systolic/diastolic ratio, maternal blood pressure, maternal cardiac output, and maternal total peripheral resistance. RESULTS: All patients demonstrated a fall in cardiac output and a rise in total peripheral resistance with standing. No change in systolic/diastolic ratio occurred with change to the upright position in patients with normotension. Patients with hypertension exhibited a significant increase in umbilical systolic/diastolic ratio with postural change. The increase was more marked in women who had hypertension with elevated peripheral resistance. CONCLUSION: Patients with hypertension are at increased risk of elevation of systolic/diastolic ratio with postural change; women with high-resistance hypertension may be at highest risk.
Diastole↗
Pregnancy loss and thrombosis with protein C deficiency.
OBJECTIVES: Protein C inhibits coagulation and promotes fibrinolysis. This study investigates the association between protein C deficiency and pregnancy loss, thrombosis in pregnancy, and thrombosis with oral contraception. STUDY DESIGN: Fifteen protein C--deficient patients and 37 controls from a single kindred were studied. An obstetric history was obtained by telephone. Data were analyzed by logistic regression, Fisher's exact test, and Student t test. RESULTS: Protein C--deficient women experienced a 33% pregnancy loss versus 19% in the controls (not significant). Thromboembolism during pregnancy in protein C--deficient women was 33% (45% in those not receiving prophylactic anticoagulation) versus 5% in controls (odds ratio 7.37, p = 0.026). Five of 12 protein C--deficient women using oral contraception developed thrombosis versus 0 of 33 controls. The risk of thrombosis for protein C--deficient women using oral contraception is increased (p < 0.001). CONCLUSIONS: Perinatal outcome is not statistically different with protein C deficiency. Protein C deficiency increases the risk of thrombosis during pregnancy and with oral contraception. Prophylactic heparin is suggested during pregnancy for protein C--deficient women with personal or family histories of thrombosis. Oral contraception is not advised.
Adult↗
The maternal hemodynamic effect of indomethacin in normal pregnancy.
The vasodilation of pregnancy is thought by many to be due to increased endothelial production of prostacyclin, a vasodilatory prostanoid. Indomethacin, a potent inhibitor of prostaglandin synthesis, is known to increase the maternal blood pressure response to angiotensin II infusion. We sought to measure directly the hemodynamic effects of a short course of indomethacin. Twenty-three healthy pregnant women with uncomplicated pregnancies between 26-32 weeks' gestation completed the study. Using Doppler technology, we determined cardiac output, stroke volume, and total peripheral resistance before and after three 25-mg doses of indomethacin. Although blood pressure did not change, peripheral resistance rose and stroke volume fell following indomethacin administration. Our findings support the hypothesis that indomethacin interferes with tonic prostaglandin-induced vasodilation in pregnancy. However, the increase in vascular resistance was very slight, suggesting that other vasodilators are also at work in pregnancy. We recommend that indomethacin be used judiciously in hypertensive pregnant patients until more information concerning possible adverse hemodynamic effects becomes available.
Blood Pressure↗
The maternal hemodynamics of preeclampsia.
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Blood Flow Velocity↗
Duplication (6q) syndrome diagnosed in utero.
We report on a case of partial duplication 6q detected ultrasonographically. The clinical picture noted in utero is consistent with the adult phenotype previously reported in the literature.
Abnormalities, Multiple↗
The effect of maternal hemodynamics on fetal growth in hypertensive pregnancies.
Seventy-six pregnancies in which hypertension complicated pregnancy before 28 weeks' gestation were studied. In 36, hemodynamics were characterized by increased cardiac output and low vascular resistance; in 32, hemodynamics were characterized by high resistance; in eight hemodynamics crossed over from high output to high resistance during pregnancy. High-resistance hypertension was associated with a mean birth weight 1058 gm less than that in the low-resistance group (p = 0.001). The reduction in birth weight was due to a 4-week difference in gestational age (p = 0.001) and lower percentile weights for gestational age, 19th versus 39th (p = 0.005). Infants in the crossover group had low percentile weights and a high rate of intrauterine fetal death.
Adult↗
The effects of oral nifedipine on hepatic blood flow in humans.
Duplex ultrasonography was used to measure changes in hepatic blood flow in 13 healthy volunteers after they received single doses of 10 mg oral nifedipine and placebo. Blood flow was measured in the hepatic artery and branches of the portal and hepatic veins at baseline and 0.3, 0.6, 1, 1.5, 2, 3, 4, and 5 hours after drug administration. Cardiac output was also measured at baseline and 1, 2, and 3 hours after dosing. Blood flow initially increased in all three vessels 0.6 hour after administration of nifedipine (29%, 56%, and 31% in the hepatic artery, hepatic vein, and portal vein, respectively) compared with placebo. Flow rapidly returned to baseline in the hepatic artery and hepatic vein, whereas it appeared to remain elevated through 3 hours in the portal vein. Nifedipine administration resulted in an increase in cardiac output of 26%, 22%, and 14% above placebo at 1, 2, and 3 hours, respectively. No significant differences were detected in the systolic, diastolic, or mean arterial blood pressures after nifedipine or placebo. This study demonstrates that nifedipine increases hepatic blood flow in a transient nature and systemic hemodynamic parameters do not necessarily reflect specific organ responses. The nifedipine-induced change in blood flow should be considered when nifedipine is coadministered with high-clearance drugs, because systemic availability may be increased.
Administration, Oral↗
Renal vascular hypertension during pregnancy.
We report two women with renal artery stenosis in pregnancy. The first patient presented with severe hypertension in the first and second trimesters characterized by an extremely high vascular resistance (maximum 2455 dyne.second.cm-5). Transluminal angioplasty was performed at 20 weeks' gestation, resulting in resolution of the patient's hypertension. After angioplasty, her vascular resistance fell to 1600 dyne.second.cm-5, but did not reach normal pregnant levels. The pregnancy was carried to term without complication. The second patient's hypertension improved during pregnancy, and she delivered at term without complication. Twelve weeks postpartum, the patient again became severely hypertensive, and transluminal angioplasty was performed.
Adult↗
Maternal hemodynamics in pregnancies complicated by hyperthyroidism.
The hemodynamics of six pregnant women with hyperthyroidism were studied before and after therapy. Cardiac output was measured by Doppler technique, and blood pressure by automated cuff. When compared with values in euthyroid pregnant women, blood pressure (83.6 mmHg, P less than .001), heart rate (89.2 beats per minute, P less than .001), cardiac output (11.2 L/minute, P less than .001), and stroke volume (123 mL, P less than .001) were significantly elevated. Total peripheral resistance was significantly reduced (609 dyne.second.cm-5, P less than .001). Despite normalization of thyroid indices after therapy, cardiac output remained markedly elevated (9.7 L/minute, P less than .001) and vascular resistance remained reduced (708 dyne.second.cm-5, P = .01). Although the hemodynamics of pregnant thyrotoxic women normalize with therapy, they remain significantly hyperdynamic.
Echocardiography, Doppler↗
Maternal hemodynamics and aortic diameter in normal and hypertensive pregnancies.
The aortic diameters of 89 normotensive pregnant women were compared with those of nine rigorously defined preeclamptic women and 59 women who required antihypertensive therapy. Over the course of normal pregnancy, the diameter increased significantly; it was larger in preeclamptic than in normotensive women throughout pregnancy. The aortic diameter in women with high-resistance hypertension was smaller than that in normotensive women and in those with high-output, low-resistance hypertension, but it was larger in women with low-resistance hypertension than in normotensive women. The aortic diameter increased after treatment of high-resistance hypertension with hydralazine, but decreased after treatment of high-output, low-resistance hypertension.
Aorta↗
Measurement of cardiac output by impedance technique.
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Cardiac Output↗
Measurement of cardiac output in pregnancy by Doppler technique.
Doppler technique of measuring cardiac output was evaluated during pregnancy. In a study of accuracy Doppler technique correlated well with thermodilution, (r = 0.95, y = 1.05x - 0.35). In a study of interoperator variability, the technique was found to be reproducible, (r = 0.92, y = 0.91x + 0.74).
Aorta↗
Maternal hemodynamics in normal and preeclamptic pregnancies: a longitudinal study.
Preeclampsia is a disease unique to pregnancy that contributes substantially to maternal and fetal morbidity and mortality. The condition has been thought to be one of hypoperfusion in which increased vascular resistance characterizes the associated hypertension. This study was designed to test an alternative hypothesis, that preeclampsia is characterized by high cardiac output. In a blinded longitudinal study of nulliparas with uncomplicated pregnancies, cardiac output was measured serially by Doppler technique. Cardiac output was elevated throughout pregnancy in patients who became preeclamptic (P = .006). Six weeks postpartum, the hypertension of the preeclamptic subjects had resolved but cardiac output remained elevated (P = .001) and peripheral resistance remained lower than in the normotensive subjects (P = .001). This study demonstrates that preeclampsia is not a disease of systemic hypoperfusion and challenges most current models of the disease based on that assumption.
Adult↗