Biomedical subjects

R Gonen

Publications and source records attributed to R Gonen.

At least 19 recordsLinked to original sources

PubMed2001

Cardiac function in fetuses with intracardiac echogenic foci.

OBJECTIVE: To evaluate cardiac dimensions and function in euploid fetuses with intracardiac echogenic foci. STUDY DESIGN: Forty-eight fetuses with a single cardiac echogenic focus situated in the left ventricle had echocardiography performed at 22-24 weeks of gestation. Fifty normal fetuses at 22-24 weeks' gestation served as controls. Two-dimensional and M-mode directed fetal echocardiography were used to exclude cardiac anomalies and measure right and left ventricular free walls and interventricular septal thickness and ventricular systolic and diastolic dimensions. Cardiac size was expressed as a ratio of ventricular wall thickness/biparietal diameter, and cardiac function was expressed as ventricular shortening fraction. Doppler fetal echocardiography measurements included pulmonary and aortic maximum systolic velocities and time to peak velocities as indices of ventricular systolic function, and the ratio between early ventricular filling (E-wave) and active atrial filling (A-wave) peak velocities at the level of the atrioventricular valves as an index of ventricular diastolic function. RESULTS: Early ventricular filling/active atrial filling peak velocity ratios were significantly lower in fetuses with intracardiac echogenic foci than in control fetuses. In the mitral valve the ratio was 0.37 +/- 0.14 (0.039) (mean +/- SD (95% confidence interval for difference between the means)) vs. 0.59 +/- 0.19 (0.052) and in the tricuspid valve it was 0.42 +/- 0.16 (0.045) vs. 0.62 +/- 0.21 (0.058). No significant differences were found in cardiac dimensions, ventricular shortening fraction and Doppler systolic indices. CONCLUSION: Euploid fetuses with intracardiac echogenic foci show low E/A ratio values in midtrimester echocardiography. This finding might indicate cardiac diastolic dysfunction.

Blood Flow Velocity↗

PubMed2001

Candida sepsis following transcervical chorionic villi sampling.

BACKGROUND: The use of invasive devices and broad spectrum antibiotics has increased the rate of candidal superinfections. Candida sepsis associated with pregnancy is rare. Candida sepsis following chorionic villi sampling (CVS) has never been reported. CASE: A 31 -year-old pregnant woman presented with signs of sepsis one day after undergoing transcervical CVS. Blood culture and curettage material yielded C. albicans. She was treated with 400 mg of fluconazole daily for 4 weeks and completely recovered. CONCLUSION: Candida sepsis should be considered in the differential diagnosis of sepsis following CVS.

Adult↗

PubMed2001

Early second-trimester low umbilical coiling index predicts small-for-gestational-age fetuses.

OBJECTIVE: To evaluate the role of the early second-trimester Doppler velocimetric studies of the umbilical coiling index and umbilical cord cross-sectional area as tests for the prediction of small-for-gestational age infants. METHODS: Doppler blood flow studies in 147 singleton pregnancies at risk for delivery of a small-for-gestational-age neonate were performed at 15 +/- 1 (SD) weeks' gestation from the uterine artery, umbilical artery, middle cerebral artery, inferior vena cava, and ductus venosus. Pulsatility index values were calculated for the arteries, and preload index values and systolic-atrial contraction ratios were calculated for the veins. The sonographic cross-sectional area of the umbilical cord was measured in a plane adjacent to the insertion into the fetal abdomen. The umbilical coiling index was calculated by using sonographic longitudinal views of cord vessels from several segments antenatally and by dividing the total number of helices by cord length (centimeters) postnatally. Small-for-gestational-age neonates were identified when the birth weight was below the 10th percentile for gestational age. RESULTS: Among 147 pregnancies studied, 124 fulfilled the study criteria. Thirty-nine of the neonates were small for gestational age at birth (31.5%). The mean +/- SD gestational age at delivery of the appropriate-for-gestational-age neonates was 39.7 +/- 1.28 weeks, and that of the small-for-gestational-age neonates was 36.4 +/- 2.9 weeks (range, 28-40 weeks). The best single predictor of a small-for-gestational-age infant was the coiling index, with sensitivity of 79%, specificity of 86%, a positive predictive value of 72%, and a negative predictive value of 90%. CONCLUSIONS: The umbilical coiling index measured in the second trimester is useful in predicting the birth of a small-for-gestational-age infant and may serve as a marker for subsequent growth restriction.

Blood Flow Velocity↗

PubMed2000

Potential role of high-frequency ventilation in the treatment of severe congenital pleural effusion.

Newborns with severe congenital pleural effusions often present with respiratory failure at birth. We describe two premature infants born at 31 and 33 weeks of gestation with bilateral pleural effusions. Both were drained prior to delivery under ultrasound guidance. The first infant had severe bilateral congenital chylothorax with pulmonary hypertension; the second infant had severe nonimmune hydrops fetalis. Both could be adequately oxygenated but failed to respond to conventional mechanical ventilation (CMV) and chest tube drainage, so that CO(2) elimination could not be accomplished. Both infants were successfully treated with high-frequency ventilation (HFV). We suggest that HFV may be of significant value in establishing adequate ventilation in cases of severe congenital pleural effusions.

Adult↗

PubMed2000

Association between epidural analgesia and intrapartum fever.

The objective of this paper is to determine whether or not epidural analgesia is an independent risk factor for intrapartum fever. Maternal temperature was measured every 4 h during labor to 1004 consecutive women in term labor. Women with fever or on antibiotics were excluded. Epidural analgesia was administered upon patients' request. Of the 406 (40%) women who received epidural analgesia, 11.8% (n = 48) developed a fever > or = 37.8 degrees C during labor compared with only 0.2% (n = 1) of women not receiving epidural analgesia. Women who received epidural analgesia were more likely to have one or more risk factors for intrapartum infection. Their labor and ruptured membranes were longer, they were more likely to have internal monitoring and have more vaginal examinations. Compared with women who received epidural analgesia and did not develop intrapartum fever, women that did develop fever had longer epidurals and more risk factors for infection. However, in a logistic regression analysis with fever as dependent variable, only the duration of epidural was significantly associated with the occurrence of fever. The rate of fever increased with longer labors, from 5% with labor < 3 h to 28% with labor > 6 h. In 90% of women the fever resolved within a few hours after delivery. Sepsis evaluation was negative in all of the newborns to mother who had intrapartum fever. Our data support a noninfectious etiology for intrapartum fever in the vast majority of our patients. However, infection must be ruled out before a decision is made to withhold antibiotic therapy.

Adult↗

PubMed2000

Effects of a policy of elective cesarean delivery in cases of suspected fetal macrosomia on the incidence of brachial plexus injury and the rate of cesarean delivery.

OBJECTIVE: The aim of this study was to examine the effects of a policy of elective cesarean delivery for suspected fetal macrosomia on the incidence of brachial palsy and on the cesarean delivery rate. STUDY DESIGN: We performed a retrospective assessment of a policy that recommends cesarean delivery for macrosomia (fetal weight > or =4500 g). Fetal weight was estimated by palpation, and ultrasonographic weight estimation was carried out whenever macrosomia was suspected. RESULTS: During the 4 years of the study 16,416 deliveries resulted in 133 infants with macrosomia (0.8%). Macrosomia was suspected in 47 cases and confirmed by birth weight in 21 (45%). Antenatal estimation of fetal weight was carried out for 115 of the fetuses with macrosomia (86%). Macrosomia was correctly predicted in 21 of 115 cases (18.3%). Thirteen infants with undiagnosed macrosomia were delivered by emergency cesarean procedures, and 99 were delivered vaginally. Three infants with macrosomia (3%) and 14 infants without macrosomia (0.1%) sustained brachial plexus injury. Our policy prevented at most a single case of brachial palsy, and it contributed 0.16% to our cesarean delivery rate. CONCLUSIONS: A policy of elective cesarean delivery in cases of suspected fetal macrosomia had an insignificant effect on the incidence of brachial plexus injury. Its contribution to the rate of cesarean delivery was also small.

Birth Injuries↗

PubMed2000

Selected abstracts

Explore the source record for details and available documents.

Journal Article↗

PubMed1999

Intrapartum drainage of fetal pleural effusion.

Our objective was to describe our experience with intrapartum thoracocentesis in fetuses with severe bilateral pleural effusion. We describe the outcome of four consecutive cases of fetal pleural effusion due to chylothorax that were managed by intrapartum thoracocentesis. These fetuses were not candidates for pleuro-amniotic shunting either because of the need for prompt delivery (three fetuses) or because of advanced gestational age (one fetus). Thoracocentesis was performed in the operating theatre under ultrasound guidance prior to Caesarean delivery. Gestational age at the time of diagnosis and thoracocentesis ranged between 26-34 weeks and 31-34 weeks respectively. Bilateral thoracocentesis was performed in two fetuses and unilateral in the remaining two fetuses. All four infants were born in a relatively good condition; however, all eventually required intubation, ventilation and chest tubes. Chest tubes were introduced between 2 h and 5 days after delivery in three infants, and immediately after birth in one infant who was hydropic. Two infants survived and are developing normally. One infant died from sepsis following successful pleurodesis and one from aspiration on day 51. Our conclusions are that intrapartum thoracocentesis seems to be a relatively simple procedure, that allows newborns with pleural effusion, to breathe spontaneously or be more easily ventilated. This in turn, reduces the need to introduce chest tubes in an emergency situation.

Drainage↗

PubMed1998

Prediction of successful induction of labor: comparison of transvaginal ultrasonography and the Bishop score.

OBJECTIVE: To determine whether transvaginal ultrasonography of the cervix before induction of labor is a better predictor of successful induction than the Bishop score. STUDY DESIGN: Eighty-six consecutive patients scheduled for induction of labor underwent digital cervical examination followed by transvaginal ultrasonography to measure cervical length and to determine the presence of wedging. Patients were induced with either oxytocin or intracervical prostaglandin E2 gel followed by oxytocin when required. The agent for induction was selected on the basis of the digital examination. The primary outcome criteria were successful induction and the duration of labor. RESULTS: Successful induction and the duration of labor were significantly associated with the Bishop score and cervical length. Cervical wedging was associated only with successful induction. However, in a logistic regression model that included these parameters as independent variables, only the Bishop score and parity were significantly correlated with successful induction and the duration of labor. CONCLUSIONS: Transvaginal ultrasonographic evaluation of the cervix before induction of labor does not improve the prediction of cervical inducibility obtained by the Bishop score.

Adult↗

PubMed1998

Myometrial thickness in pregnancy: longitudinal sonographic study.

The purpose of this study was to evaluate in vivo the changes in myometrial thickness throughout pregnancy. Myometrial thickness was measured in 25 singleton uncomplicated pregnancies. Ultrasonographic sagittal and transverse sections were used to measure uterine wall thickness from the low anterior wall (lower segment) and the anterior, posterior, right, and left walls of the upper segment and from the fundus. In each case four measurements were made in the second and third trimesters. Myometrial thickness of the upper uterine segment remains fairly constant in the first and second trimesters of pregnancy, whereas a significant linear trend was found between a decreasing thickness of the lower uterine segment and advancing gestational age. Myometrial thickness is significantly increased behind the placental insertion site as compared to other portions of the uterine wall. These data may serve as baseline reference values for further studies in the antepartum fetal surveillance of high-risk pregnancies.

Adult↗

PubMed1998

Differences between Twin Umbilical Coiling Indices Correlate to Differences in Twin Weight and Doppler Indices.

> Objective: The aim of our study was to evaluate sonographic and Doppler detectable differences in umbilical coiling index and fetoplacental circulation of discordant twins. Study Design: Doppler blood flow studies in 13 pairs of concordant and 20 pairs of discordant twins were performed from umbilical artery, middle cerebral artery, inferior vena cava, and ductus venosus. Flow studies were compared and correlated with the antenatal sonographic coiling index and the actual umbilical cord length, number of vascular helices, and birth weight. All studies were performed within 72 h before delivery. Pulsatility index (PI) values were calculated for the arteries and preload index (PLI) values for the veins. The umbilical coiling index (CI) was calculated using sonographic longitudinal views of cord vessels from several segments antenatally and by dividing the total number of helices by cord length (cm) postnatally. Discordancy was defined as a more than 20% intrapair actual birth weight difference. For all these index values the intertwin differences (Delta values) were calculated by subtracting the values obtained in the larger twin with those of the smaller twin. Results: The mean +/- SD intertwin difference in umbilical coiling index was 27.4 +/- 10.5% in the antepartum period and 28.9 +/- 10.0% after birth. Regression analysis showed a significant linear trend (r = 0.77, P < 0.001) between intertwin birth weight difference (DeltaBW) and intertwin coiling index difference (DeltaCI). A good correlation was found between DeltaCI and DeltaPLI in the ductus venosus (r = 0.63, P < 0.05), DeltaPLI in the inferior vena cava (r = 0.51, P < 0.005), and DeltaPI in the middle cerebral artery (r = 0.44, P < 0.05). Conclusions: Intertwin difference in antepartum umbilical coiling index can be determined by ultrasound and correlates well with: 1) the actual difference in coiling indices at birth, 2) the intertwin birth weight difference and 3) the intertwin Doppler flow characteristics in the fetal cerebral and venous circulation.

Journal Article↗

PubMed1997

Fetal pyelectasis in consecutive pregnancies: a possible genetic predisposition.

Mild fetal pyelectasis is a relatively common finding. The objective of this study was to assess its recurrence rate in subsequent pregnancies. The study comprised 420 women with two consecutive normal uncomplicated pregnancies screened at 15-24 weeks' gestation by ultrasound. Pyelectasis was defined as a fetal pelvis of 4 mm or more in its anterior-posterior dimensions. Of 64 fetuses with pyelectasis, 43 (67%) had a recurrence of this finding in their subsequent pregnancy. Compared with normal fetuses, those with pyelectasis had a relative risk of 6.1 to have a recurrence of this finding in their next pregnancy (95% confidence interval, 4.3-7.5, p < 0.001). These results suggest a predisposition for pyelectusis that may be influenced by genetic and/or environmental factors. More data are needed before an accurate adjustment based on previous results can be made.

Adult↗

PubMed1996

Is macrosomia predictable, and are shoulder dystocia and birth trauma preventable?

OBJECTIVE: To assess our ability to detect macrosomic fetuses, and to examine the relationship between prenatal diagnosis of macrosomia and the incidence of shoulder dystocia and birth trauma. METHODS: We instituted a protocol for routine detection of macrosomic fetuses, defined as weight estimated to be at least 4500 g. Fetal weight was estimated by ultrasonography when there was clinical suspicion of macrosomia. We collected data on these pregnancies as well as on deliveries of macrosomic infants, shoulder dystocia, and birth trauma. RESULTS: During the 14-month study period, there were 4480 deliveries. There were 23 macrosomic newborns (0.5%), of whom 17 were born vaginally. Six of these 17 (35%) vaginal deliveries were complicated by shoulder dystocia, and one infant sustained brachial plexus injury. The overall frequency of shoulder dystocia was 2%, the majority (93%) occurring in infants weighing less than 4500 g. Eleven newborns sustained brachial plexus injury (0.2%), and 39 had isolated clavicular fracture. Six of nine cephalic deliveries that resulted in brachial plexus injury were associated with shoulder dystocia. The sensitivity and predictive value of the study protocol were 17% (four of 23) and 36% (four of 11), respectively. Surprisingly, clinical estimation alone had a sensitivity of 43% (ten of 23) and a positive predictive value of 53% (ten of 19). CONCLUSION: The ability to predict macrosomia is limited. The predictive value of clinical estimation of fetal weight alone may be slightly higher than when it is combined with ultrasonography. Because most cases of shoulder dystocia and birth trauma occur in nonmacrosomic infants, these conditions are practically impossible to prevent.

Birth Injuries↗

PubMed1996

The effect of maternal prostaglandin administration on fetal ductus venosus blood flow velocity.

Our objective was to investigate whether maternal administration of prostaglandins PGE2 and PGF2(alpha) is associated with changes in fetal ductus venosus flow velocity waveforms. Second-trimester termination of pregnancy was induced in 11 women (group A) by intra-amniotic instillation of 40 mg PGF2(alpha). In group B, 19 patients received 0.5 mg PGE2 intracervically for preinduction cervical ripening. Doppler flow velocity waveforms were recorded from the fetal ductus venosus immediately before and 40-60 min after prostaglandin administration. The paired t-test was used for statistical analysis of the ductus venosus index (DVI). The mean DVI decreased after PGF2(alpha) administration from 0.62 +/- 0.12 to 0.52 +/- 0.13 (p < 0.01); and from 0.62 +/- 0.10 to 0.58 +/- 0.12 (p < 0.05) after PGE2 administration. Atrial peak velocities were significantly increased after the procedures. No significant changes were found for systolic peak velocity values. The data indicate that major changes in ductus venosus hemodynamics are induced by PGF2(alpha) and PGE2.

Abortion, Therapeutic↗

PubMed1995

The karyotype of fetuses with anomalies detected by second trimester ultrasonography.

OBJECTIVE: To determine the incidence of abnormal karyotype among fetuses with anomalies detected by detailed second trimester ultrasonography. STUDY DESIGN: A total of 573 patients underwent amniocentesis following the detection of anomalies by detailed second trimester ultrasonography. RESULTS: Thirty-six (6.3%) fetuses with abnormal karyotype were detected. The most common abnormal karyotypes were: trisomy 18, 11 cases; trisomy 21, 8 cases; 45XO, 7 cases; trisomy 13, 3 cases; and triploidy, 2 cases. Abnormal karyotype was detected in 20/111 (18%) fetuses with more than one anomaly, 15/182 (8.2%) with cystic hygroma, and 1/38 with nuchal thickening. No abnormal karyotype was detected among 108 fetuses with choroid plexus cyst, 58 with hydronephrosis, 25 with ventriculomegaly, 16 with a single umbilical artery, 18 with cardiac anomalies. CONCLUSIONS: (1) Half of the cases with abnormal karyotype occurred in fetuses with more than one anomaly. (2) Cystic hygroma was the isolated malformations most commonly associated with abnormal karyotype. (3) Isolated malformations such as choroid plexus cyst or hydronephrosis were not associated with abnormal karyotype.

Chromosome Aberrations↗

PubMed1995

Subendometrial myometrial contractions associated with transcervical chorionic villous sampling.

Thirty-two consecutive patients, referred for prenatal diagnosis by chorionic villous sampling, were examined by transvaginal ultrasound for the presence of myometrial contractions before and after the procedure. Increased myometrial activity was observed in 78% of patients. The mean frequency increased by 3.5 times and the amplitude increased by 4.2 times compared to the preprocedure condition. Cramping was associated with the increased amplitude and/or frequency of contractions. No significant correlation was found between the direction of propagation of the contraction wave and its frequency or amplitude. The sensitivity of ultrasonographically detected myometrial contractions in predicting cramping is 70%, but only 31% in predicting vaginal bleeding or spotting. Further studies are required to elucidate the prognostic significance of this uterine activity.

Adult↗

PubMed1994

Intracervical prostaglandin E2 for induction of labor in patients with premature rupture of membranes and an unripe cervix.

The efficacy and safety of intracervical prostaglandin E2 (PGE2) gel for induction of labor in patients with premature rupture of the membranes (PROM) at term and with an unripe cervix were evaluated. Fifty-two patients who did not start labor 6 to 12 hours after PROM and who had an unripe cervix were randomized to one of two management protocols. Patients randomized to PGE2 received a single intracervical application of 0.5 mg PGE2. Patients randomized to the conservative protocol were managed expectantly for 24 hours. If labor was not established 6 hours after randomization in patients receiving PGE2 or 24 hours after PROM in patients managed expectantly, labor was induced with intravenous oxytocin. Of the patients receiving PGE2, 93% began labor after a single application, and the mean interval between prostaglandin application and delivery was 6.6 hours. In the conservative group, only 57% began labor within 24 hours, and more than half of them required augmentation with oxytocin. The mean latency between PROM and delivery was 15 hours in patients managed with PGE2 and 30 hours in patients managed conservatively (P < 0.01). There were no complications and pregnancy outcome was similar in the two groups. Intracervical PGE2 is safe and effective for inducing labor in patients with PROM and an unfavorable cervix.

Adult↗

PubMed1993

Description and partial characterization of a new Chlamydia-like microorganism.

A new obligate intracellular bacterium which we called 'Z' was isolated as a cell culture contaminant of unknown origin. The organism grew in a variety of cultured cells with a 5-7-day developmental cycle, within cytoplasmic phagosomes, similarly to Chlamydia and some Rickettsia spp. Two alternating developmental forms (elementary bodies and reticulate bodies) were observed by electron microscopy. SDS-PAGE electrophoresis, immunoblotting with chlamydia-specific antibodies, and polymerase chain reaction using chlamydial genus specific primers provided evidence that our bacterium differs significantly from chlamydiae. Further characterization of 'Z' including determination of 16S ribosomal RNA sequences will allow its taxonomic position to be established.

Animals↗