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Biomedical subjects

A W Cohen

Publications and source records attributed to A W Cohen.

At least 19 recordsLinked to original sources
PubMed1992

Maternal glucose intolerance and the subcutaneous terbutaline pump.

OBJECTIVE: Our hypothesis was that use of the subcutaneous terbutaline pump does not affect maternal glucose tolerance. STUDY DESIGN: With the 1-hour glucose tolerance test, we examined the incidence of glucose intolerance in 37 patients using the pump compared with that of 54 patients receiving oral terbutaline and 634 control subjects without risk factors for gestational diabetes. The frequency of gestational diabetes and the need for insulin to maintain glycemic control were subjected to chi 2 analysis. RESULTS: The incidence of gestational diabetes was 6% in the control subjects, 5% in patients using the pump (p = 0.8), and 11% in those on the oral therapy regimen (p = 0.4). A total of 8% of controls who had gestational diabetes required both insulin and diet, compared with 100% using the pump (p less than 0.01) and 50% on the oral terbutaline regimen (p = 0.03). CONCLUSION: The incidence of gestational diabetes is not increased in patients receiving terbutaline via the subcutaneous pump. The use of terbutaline by any route significantly increases the need for insulin to achieve glycemic control.

Administration, Oral↗
PubMed1992

The utility of the TDx test in the assessment of fetal lung maturity.

Accurate assessment of fetal lung maturity is essential in the management of high-risk obstetric patients. New rapid techniques have been developed to supplement time-consuming chromatographic methods. We compared one of these newer methods, the TDx-FLM, to the standard tests for fetal pulmonary maturity. There was an excellent correlation between the TDx and the lecithin-sphingomyelin ratio (r = 0.78). Although a TDx value of 70 or greater is considered mature, we found a value of 50 or greater predictive of fetal lung maturity in 100% of cases, and have chosen to redefine a mature value as 50 or greater in our institution. This value has greatly enhanced the clinical applicability of the test, allowing use of a large number of specimens from the previously poorly understood and often disregarded borderline category.

Amniotic Fluid↗
PubMed1992

Pregnancies complicated by liver disease and liver dysfunction.

Although liver dysfunction is infrequently seen in pregnancy, it can result in severe maternal and fetal compromise. An unrecognized case of acute fatty liver may result in both maternal and fetal death. Failure to screen for hepatitis B can result in a newborn who will be a hepatitis carrier for life. Because of such consequences, the obstetrician must remain vigilant for signs of liver dysfunction and must understand the pathophysiology of these disorders.

Cholestasis, Intrahepatic↗
PubMed1991

Intrapartum course of fetuses with isolated hypoplastic left heart syndrome.

Once considered universally fatal, the hypoplastic left heart syndrome is now being surgically treated in the newborn period. To help formulate an appropriate management plan for the labor and delivery of these patients, we reviewed the intrapartum course and immediate neonatal outcome of 13 fetuses with known hypoplastic left heart syndrome. Eleven of 13 patients underwent labor, and only one had an abnormal fetal heart pattern. There were no cases with meconium staining of the amniotic fluid. All patients with spontaneous or induced labor were delivered vaginally. There were no Apgar scores less than 8 at 5 minutes, and all umbilical cord blood pH values were greater than or equal to 7.20. All infants survived to undergo initial reconstructive surgery. We conclude that labor does not appear to be a high-risk situation for the fetus with this disorder. Routine intrapartum fetal heart rate monitoring can be used, oxytocin can be used as indicated, and cesarean section should be reserved for traditional obstetric indications.

Female↗
PubMed1991

Venous Doppler ultrasonography in the fetus with nonimmune hydrops.

Eighteen pregnancies with nonimmune hydrops fetalis were referred for fetal echocardiography to rule out congenital heart disease. In 14 of these cases, pulsating blood velocities were recorded in the umbilical vein, which in a normal population had a nonpulsatile blood velocity pattern. The four cases without pulsations in the umbilical vein were found to have intrauterine viral infections. In the last 10 cases examined, the umbilical venous pulsations were found to reflect abnormal central venous pulsations during atrial systole suggesting increased fetal central venous pressure. Right ventricular shortening fraction was significantly decreased in the group with umbilical venous pulsations compared with those without (0.18 versus 0.32, p less than 0.05). All the fetuses without venous pulsations survived, but only four of the 14 with pulsations survived (p less than 0.05). The results suggest that blood velocity recordings in the umbilical and central veins of the fetus can give valuable clinical information with regard to the presence of fetal congestive heart failure and differentiate between this physiologic state and other causes of nonimmune hydrops fetalis. This may have implications for fetal diagnostic work-up and prognosis.

Blood Flow Velocity↗
PubMed1991

Fetal well-being: nonimaging assessment and the biophysical profile.

All of the testing methods described above are very good at predicting continued fetal health when test results are reassuring. Each test also suffers from a very poor ability to predict compromise when results are abnormal. Thus, the primary value of antepartum fetal monitoring is in identifying those pregnancies that do not require immediate intervention and may be allowed to continue. Certainly, all pregnant women (regardless of risk status) should monitor fetal movement as part of their fetal surveillance. For patients at risk, a variety of testing schemes are available using combinations of the NST, CST and BPP. There are several reasons for using the NST as the primary testing method for those at risk. Even a small antenatal testing area can accommodate three or four FHR monitors, and a single antenatal testing nurse can perform several NSTs at a time. Because the BPP requires an ultrasound machine and a trained technician to perform, and because only one BPP can be done at a time, many obstetricians who do their own in-office fetal testing are unable to adopt BPP testing as their primary means of surveillance. Additionally, it is more economical to use the NST than the BPP for first-line testing. Assuming charges of $150 and $300 for the NST and BPP, respectively, and assuming that 20% of NSTs are nonreactive and require a BPP for second-line testing, the weekly cost of testing 100 patients is $21,000 for the NST and $37,500 for the BPP. This increase-in-testing cost must be balanced against the small improvement in perinatal mortality rates achieved with the use of the BPP. Because it must be performed in a hospital setting and takes an average of 90 minutes to complete, the CST is more expensive and time-consuming than either the NST or BPP and it is less frequently used as the primary method of fetal testing. In the past the CST was the most commonly used secondary test after a nonreactive NST, but use of the BPP in this situation has now become commonplace. Although the CST still has an important role in fetal testing, the BPP is better suited for use in this setting because of its technical ease and low incidence of abnormal results. Thus, many centers use the NST as the primary mode of testing for the fetus at risk, often with a sonographic assessment of AFV.(ABSTRACT TRUNCATED AT 400 WORDS)

Female↗
PubMed1991

Doppler echocardiography of fetal ductus arteriosus constriction versus increased right ventricular output.

A prospective longitudinal study from 121 examinations of 41 normal pregnant women showed that fetal ductal flow velocities increased with gestational age. These normal data were compared with data in three groups of fetuses with altered ductal flow velocities: 22 fetuses (mean gestational age 31.3 weeks) had ductal constriction due to maternal indomethacin treatment; 10 fetuses (mean gestational age 27.9 weeks) had been exposed to terbutaline, a positive inotropic agent and 14 fetuses (mean gestational age 33.3 weeks) had hypoplastic left heart syndrome. In normal fetuses maximal systolic, mean and end-diastolic ductal flow velocities increased linearly (p less than 0.0001). The pulsatility index did not change (mean +/- 2 SD: 2.46 +/- 0.52). Fetuses with ductal constriction had higher maximal, mean and end-diastolic flow velocities and a significantly lower pulsatility index than did normal fetuses (1.25 +/- 0.76; p less than 0.0005). Six of 10 fetuses of the terbutaline group and 8 of 14 fetuses with hypoplastic left heart syndrome had increased maximal flow velocity, but normal or only mildly elevated mean flow velocity. The pulsatility index in fetuses during terbutaline therapy and with hypoplastic left heart syndrome was significantly higher than in normal fetuses (3.11 +/- 0.46 and 3.09 +/- 0.7, respectively, vs. 2.46 +/- 0.52; p less than 0.0005). Fetal ductal waveform analysis was necessary to distinguish fetal ductal constriction from increased right ventricular output. These measurements may be helpful in the diagnosis of left-sided outflow obstruction and assessment of fetal hemodynamic data.

Blood Flow Velocity↗
PubMed1991

Measurement of systolic-diastolic ratio in the umbilical artery by continuous-wave and pulsed-wave Doppler ultrasound: comparison at different sites.

Analysis of umbilical artery flow velocity waveforms, especially systolic-diastolic (S-D) ratio, can predict some pregnancy abnormalities. Most of the earlier studies did not specify the exact segment of umbilical artery sampled. We studied 53 normal singleton pregnancies between 18-41 weeks' gestation to compare S-D ratio measurements of the umbilical artery at different sites: 1) abdominal insertion site, 2) placental insertion site, 3) mid-cord, and 4) an undetermined site. The mean S-D ratio was significantly different (P less than .01) at various segments of the umbilical artery--higher near the abdominal insertion site when compared with the mid-cord, near-placental, and undetermined sites. The S-D ratio at mid-cord was higher than at the undetermined site and the placental insertion site. The near-placental-site S-D ratio was not different from the undetermined site. A lower S-D ratio at the undetermined site may not adequately reflect the true physiologic status of the fetus. Specifying the site of measurement should be an integral part of any report, in order to describe accurately the pathophysiology of fetoplacental circulatory diseases.

Blood Flow Velocity↗
PubMed1991

Can umbilical and arcuate artery Doppler velocimetry predict fetal distress among prolonged pregnancies?

We studied umbilical and arcuate artery Doppler velocity waveforms in 30 uncompromised prolonged pregnancies (greater than 41 weeks of gestation). Normal systolic/diastolic ratios in these vessels had a negative predictive value similar to other antepartum tests. The positive predictive value, though, was not high enough to consider Doppler studies of the umbilical and arcuate arteries as the only test to identify the group of prolonged pregnancies that have uteroplacental insufficiency. There is a possibility that the combination of Doppler velocimetry with other antepartum tests may improve our ability to predict poor outcome. Further study is needed.

Arteries↗
PubMed1991

Prenatal care, screening, and complications.

Articles are reviewed that give the clinician new guidelines to diagnose neural tube defects without using amniocentesis. Cervical measurement using ultrasound as a tool to objectively evaluate and follow patients at risk for premature labor and incompetent cervix are reviewed. The utility of transabdominal versus transvaginal ultrasound is discussed. Two papers are presented that look at the use of aspirin in preeclampsia. One study looks at metabolic degradation of the prostaglandins associated with pregnancy-induced hypertension and shows that there is a heterogeneity in response to aspirin therapy. However, once the patient has pregnancy-induced hypertension, aspirin does not seem to be effective. A paper is presented that looks at the safety of autologous blood donation for both the mother and the baby and confirms its usefulness in obstetrics as in the nonpregnant patient.

Aspirin↗
PubMed1991

Preeclampsia, trisomy 13, and the placental bed.

Genetic predisposition and abnormal trophoblastic function are thought to contribute to the development of preeclampsia. A multipara developed severe preeclampsia and subsequently delivered a live growth-retarded infant with trisomy 13. Biopsy of the placental bed taken immediately after delivery demonstrated inadequate trophoblastic remodeling of the maternal uterine vasculature, with an absence of normal physiologic changes in the spiral arteries. This case suggests that fetal trisomy 13 can be associated with preeclampsia in multiparous women and that abnormal trophoblastic invasion may contribute to the pathophysiology.

Adult↗
PubMed1991

Management of the pregnant patient with a cerebral venous angioma: a report of two cases.

Though there is a large body of knowledge regarding the management of pregnant women with arterial lesions in the central nervous system, little information is available on venous malformations. We report our experience with two pregnant patients with cerebral venous angiomas. These lesions are usually asymptomatic and only rarely cause seizures or subarachnoid hemorrhage. Based on our experience and literature review, we suggest that patients with venous angiomas without a history of hemorrhage can safely undergo labor and vaginal delivery.

Adult↗
PubMed1990

Cost-effective approach to office screening for gestational diabetes.

Gestational diabetes is a common problem during pregnancy. There are numerous screening programs, all of which are costly and time consuming. During a 6-month period, 50 patients were screened for gestational diabetes with a standard 50-g oral glucose load, and 1 hour later a capillary blood specimen was evaluated by means of a reflectance meter and a venous sample was evaluated in the hospital laboratory. We found that the capillary blood glucose determination was accurate, but we recommend that specific cutoff values for each meter be established for each facility. By using the glucose reflectance meter, 90% of patients will not require laboratory studies, which results in significant cost savings. Besides cost savings, the immediate results obtained by a reflectance meter allow for prompt identification of an abnormal screen and prompt scheduling for further evaluation of glucose intolerance during the pregnancy.

Blood Glucose↗
PubMed1990

Safety of predeposit autologous blood donation in the third trimester of pregnancy.

The option of predeposit autologous blood donation (PABD) before elective surgery has been gaining popularity as a means of eliminating the transmission of the acquired immune deficiency syndrome and hepatitis. It also prevents potential antigen sensitization and transfusion reactions. The use of PABD in pregnant women has been described, but its safety for both mother and fetus, especially in the first and third trimester, has not been established. After studying 16 third-trimester pregnant women with antenatal surveillance techniques and continuous fetal monitoring, we concluded that PABD is a safe procedure for both mother and fetus.

Adult↗
PubMed1990

Patient attitude toward home uterine activity monitoring.

Forty private patients using a home uterine activity monitoring system and daily contact with nursing staff (Term Guard monitor and Tokos Perinatal Nursing Service; Tokos Medical Corp., Santa Ana, CA) were surveyed after delivery. Twenty-seven responses (67.5%) were obtained. The majority of the responding patients (81%) felt that the monitor helped their pregnancy and 92% would recommend it to family and friends. Eighty-five percent thought that the monitor and related nursing services would be something that they would use in future pregnancies. No subject concluded that the monitor depersonalized their obstetric care. Forty-one percent of the patients felt that the device was an intrusion into their life-style. Seventy-eight percent thought that the device was beneficial in their understanding of preterm labor and in learning to perceive their own baseline uterine activity. Almost 60% of the subjects noted that the monitor was useful in determining uterine activity because they did not perceive any contractions. Approximately 65% felt that unnecessary trips to the hospital for prolonged monitoring were prevented by the availability of 24-hour-a-day, 7-day-a-week emergency transmission and nurse contact. Nearly three-fourths of the patients felt that unnecessary calls to the physician were prevented by their ability to monitor. In summary, the services were well accepted by the patients and, despite the intrusion into their life-style, most felt that home uterine activity monitoring improved the outcome of their pregnancy.

Attitude to Health↗
PubMed1986

Cefoxitin versus clindamycin and gentamicin in the treatment of postcesarean section infections.

Cefoxitin, a cefamycin derivative, has demonstrated activity against a broad spectrum of aerobic and anaerobic bacterial pathogens. The efficacy and safety of cefoxitin were compared with that of the combination of clindamycin and gentamicin in the treatment of postcesarean section infection. Ninety-eight patients were evaluated. Cefoxitin cured 36 of 48 patients (75%); clindamycin/gentamicin cured 38 of 50 (76%) (P greater than .05). Febrile degree hours and length of hospital stay did not differ between the two study groups. No patient experienced abscess formation or septic pelvic thrombophlebitis. Both therapies were well tolerated. In the authors' experience, cefoxitin as a single agent was as effective in the treatment of postoperative pelvic infection as the combination of clindamycin and gentamicin.

Adult↗
PubMed1985

High-risk obstetrics. The three-year experience of four subspecialists.

The development of maternal-fetal medicine as a subspecialty in obstetrics and gynecology is fairly new. The specialists involved in this area are usually hospital based and involved in multiple activities, including teaching, administration and research. The role of this subspecialist as a provider of primary care to a high-risk obstetric population is important but has not been reported on previously. In this context high-risk obstetrics refers to intercurrent obstetric problems, previous obstetric problems, previous medical problems, infertility and the supposedly high-risk group of physicians and physicians' wives.

Female↗