Diagnosis of fetal non-chromosomal abnormalities on routine ultrasound examination at 11-13 weeks' gestation

OBJECTIVE

To examine the performance of the routine 11-13-week scan in detecting fetal non-chromosomal abnormalities.

METHODS

This was a retrospective study of prospectively collected data from 100 997 singleton pregnancies attending for a routine ultrasound examination of fetal anatomy, performed according to a standardized protocol, at 11-13 weeks' gestation. All continuing pregnancies had an additional scan at 18-24 weeks and 71 754 had a scan at either 30-34 or 35-37 weeks. The final diagnosis of fetal abnormality was based on the results of postnatal examination in cases of live birth and on the findings of the last ultrasound examination in cases of pregnancy termination, miscarriage or stillbirth. The performance of the 11-13-week scan in the detection of fetal abnormalities was determined.

RESULTS

The study population contained 1720 (1.7%) pregnancies with a fetal abnormality, including 474 (27.6%) detected on the first-trimester scan, 926 (53.8%) detected on the second-trimester scan and 320 (18.6%) detected in the third trimester or postnatally. At 11-13 weeks' gestation, we diagnosed all cases of acrania, alobar holoprosencephaly, encephalocele, tricuspid or pulmonary atresia, pentalogy of Cantrell, ectopia cordis, exomphalos, gastroschisis and body-stalk anomaly and > 50% of cases of open spina bifida, hypoplastic left heart syndrome, atrioventricular septal defect, complex heart defect, left atrial isomerism (interrupted inferior vena cava with normal intracardiac anatomy), lower urinary tract obstruction, absence of extremities, fetal akinesia deformation sequence and lethal skeletal dysplasia. Common abnormalities that were detected in < 10% of cases at 11-13 weeks included ventriculomegaly, agenesis of the corpus callosum, isolated cleft lip, congenital pulmonary airway malformation, ventricular septal defect, abdominal cysts, unilateral renal agenesis or multicystic kidney, hydronephrosis, duplex kidney, hypospadias and talipes.

CONCLUSIONS

A routine 11-13-week scan, carried out according to a standardized protocol, can identify many severe non-chromosomal fetal abnormalities. A summary statistic of the performance of the first-trimester scan is futile because some abnormalities are always detectable, whereas others are either non-detectable or sometimes detectable. To maximize prenatal detection of abnormalities, additional scans in both the second and third trimesters are necessary. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Computerized fetal heart rate analysis, Doppler ultrasound and biophysical profile score in the prediction of acid-base status of growth-restricted fetuses

OBJECTIVE

To investigate the performance of non-stress test (NST), computerized fetal heart rate analysis (cCTG), biophysical profile scoring (BPS) and arterial and venous Doppler ultrasound investigation in the prediction of acid-base status in fetal growth restriction.

METHODS

Growth-restricted fetuses, defined by abdominal circumference < 5(th) percentile and umbilical artery (UA) pulsatility index > 95(th) percentile, were tested by NST, cCTG, BPS, and UA, middle cerebral artery (MCA), ductus venosus (DV) and umbilical vein (UV) Doppler investigation. The short-term variation (STV) of the fetal heart rate was calculated using the Oxford Sonicaid 8002 cCTG system. Relationships between antenatal test results and cord artery pH < 7.20 were investigated, using correlation, parametric and non-parametric tests.

RESULTS

Fifty-six of 58 patients (96.6%) received complete assessment of all variables. All were delivered by pre-labor Cesarean section at a median gestational age of 30 + 6 weeks. The UA pulsatility index (PI) was negatively correlated with the cCTG STV (Pearson correlation - 0.29, P < 0.05). The DV PI was negatively correlated with the pH (Pearson correlation - 0.30, P < 0.02). The cCTG mean minute variation and pH were not significantly correlated (Pearson correlation 0.13, P = 0.34). UV pulsations identified the highest proportion of neonates with a low birth pH (9/17, 53%), the highest number of false positives among patients with an abnormal BPS, abnormal DV Doppler and a STV < 3.5 ms, and also stratified false negatives among patients with an equivocal or normal BPS. Abnormal DV Doppler correctly identified false positives among patients with an abnormal BPS. cCTG reduced the rate of an equivocal BPS from 16% to 7.1% when substituted for the traditional NST. Elevated DV Doppler index and umbilical venous pulsations predicted a low pH with 73% sensitivity and 90% specificity (P = 0.008).

CONCLUSION

In fetal growth restriction with placental insufficiency, venous Doppler investigation provides the best prediction of acid-base status. The cCTG performs best when combined with venous Doppler or as a substitute for the traditional NST in the BPS.

Second-trimester uterine artery Doppler screening in unselected populations: a review

OBJECTIVE

Doppler ultrasound provides a non-invasive method for the study of the uteroplacental circulation. In normal pregnancy, impedance to flow in the uterine arteries decreases with gestation, which may be the consequence of trophoblastic invasion of the spiral arteries and their conversion into low-resistance vessels. Pre-eclampsia and fetal growth restriction are associated with failure of trophoblastic invasion of spiral arteries, and Doppler studies, in these conditions, have shown that impedance to flow in the uterine arteries is increased. A series of screening studies involving assessment of impedance to flow in the uterine arteries have examined the potential value of Doppler in identifying pregnancies at risk of the complications of impaired placentation. This review examines the findings of Doppler studies in unselected populations.

METHODS

Searches of a computerized medical database were performed to identify relevant studies. Only those studies that provided sufficient data to allow calculation of the performance of the test were included in the analysis. Likelihood ratios were calculated for each study and are reported for pre-eclampsia, fetal growth restriction and perinatal death as well as for more severe forms of pre-eclampsia and fetal growth restriction.

RESULTS

The literature search identified 19 relevant studies, four of which were excluded from the further analysis. The main characteristics and results of the 15 remaining studies provided discrepant results, which may be the consequence of differences in Doppler technique for sampling, the definition of abnormal flow velocity waveform, differences in the populations examined, the gestational age at which women were studied and different criteria for the diagnosis of pre-eclampsia and fetal growth restriction. Nevertheless, the studies provided evidence that increased impedance to flow in the uterine arteries is associated with increased risk for subsequent development of pre-eclampsia, fetal growth restriction and perinatal death. In addition, women with normal impedance to flow in the uterine arteries constituted a group that have a low risk of developing obstetric complications related to uteroplacental insufficiency.

CONCLUSIONS

The review suggests that increased impedance to flow in the uterine arteries in pregnancies attending for routine antenatal care identifies about 40% of those who subsequently develop pre-eclampsia and about 20% of those who develop fetal growth restriction. Following a positive test, the likelihood of these complications is increased by about 6 and 3.5 times, respectively.

Blackfan-Diamond anemia and dyserythropoietic anemia presenting with increased nuchal translucency at 12 weeks of gestation

Blackfan-Diamond anemia is a congenital hypoplastic anemia with a birth prevalence of about 1 in 200,000, usually presenting in the first few months of life and commonly associated with cardiac, urogenital and digital anomalies. Congenital dyserythropoietic anemias are a group of rare congenital anemias characterized by ineffective erythropoiesis. We report on two cases of congenital fetal anemia, one with Blackfan-Diamond anemia and one with dyserythropoietic anemia, presenting with increased nuchal translucency at 12 weeks of gestation.

Congenital nephrotic syndrome presenting with increased nuchal translucency in the first trimester

Congenital nephrotic syndrome of the Finnish type (CNF) and diffuse mesangial sclerosis (DMS) are rare causes of renal failure in infants. We report two cases, one of each condition, presenting with increased nuchal translucency at the 11-14-week scan, and review the literature.

Transplantation of highly purified CD34+Thy-1+ hematopoietic stem cells in patients with metastatic breast cancer

We report here the transplantation of extensively purified "mobilized" peripheral blood CD34Thy-1 hematopoietic stem cells from 22 patients with recurrent or metastatic breast cancer. Patients were mobilized with either high-dose granulocyte colony-stimulating factor (G-CSF) alone or cyclophosphamide plus G-CSE Median purity of the stem cell product at cryopreservation was 95.3% (range, 91.1%-98.3%), and viability was 98.6% (range, 96.5%-100%). After high-dose chemotherapy with carmustine, cisplatin, and cyclophosphamide, CD34+Thy-1 cells at a median dose of 11.3 x 10(5) per kilogram (range, 4.7-163 x 10(5) per kilogram) were infused. No infusion-related toxicity was observed. Neutrophil recovery was prompt, with median absolute neutrophil count >500/microL by day 10 (range, 8-15 days) and >1000/microL by day 11 (range, 8-17 days). Median platelet recovery (>20,000/microL) was observed by day 14 (range, 9-42 days) and >50,000/microL by day 17 (range, 11-49 days). Tumor cell depletion below the limits of detection of a sensitive immunofluorescence-based assay was accomplished in all patients who had detectable tumor cells in apheresis products before processing. Although CD4+ T-cell reconstitution was slow, no unusual infections were observed. Neither early nor late graft failure was observed, and no patient required infusion of unmanipulated backup cells. At a median follow-up of approximately 1.4 years and a maximum follow-up of 2.5 years, 16 of the 22 patients remain alive, with 9 free of disease progression, and have stable blood counts. In summary, highly purified CD34+Thy-1+ cells used as the sole source of the hematopoietic graft result in rapid and sustained hematopoietic engraftment.

2-Substituted-4-methoxybenzimidazole-based PDE4 inhibitors

A new family of PDE4 inhibitors based on a benzimidazole framework is described. Several of these compounds are orally bioavailable and show efficacy in in vivo models of inflammatory disease.

Objective and subjective assessment of abnormal uterine artery Doppler flow velocity waveforms

OBJECTIVE

Abnormal uterine artery Doppler waveforms in the second trimester of pregnancy can predict adverse outcome. The presence of a diastolic notch is a better predictor than measurement of impedance indices. A notch has generally been assessed subjectively, which has raised questions as to the reproducibility of the method. The aim of this study was to compare subjective and objective assessments of 50 abnormal waveforms.

DESIGN

This was a retrospective study of 50 abnormal uterine artery waveforms collected during a previous screening study. Subjective and objective assessments were compared and related to adverse outcomes. Five impedance indices incorporating a measurement of the diastolic notch were compared. Three indices predictive of adverse outcome were compared to subjective assessment.

RESULTS

There was good agreement between experienced operators in their subjective assessment of uterine artery waveforms. Adverse outcome was predicted by only moderately or severely abnormal waveforms. Three impedance indices predictive of adverse outcome were the pulsatility index (PI), A/C and (D - C)/B (where A is the peak systolic, D is the maximum diastolic and B is the end-diastolic frequency, and C is the nadir of the notch). The cut-off values combining the highest sensitivity for the lowest false-positive rate were 1.5 for PI, 3.0 for A/C and 0.15 for (D - C)/B. A PI of 1.5 had the highest sensitivity (100%) and positive predictive value (55%) for adverse outcome in this preselected group. These three indices were compared to subjective assessment using the kappa index and the (D - C)/B ratio had the closest agreement, although all three indices showed at least moderate agreement. The cut-off values of 1.5, 3.0 and 0.15 for PI, A/C and (D - C)/B, respectively appear to differentiate between mildly abnormal waveforms and moderately/severely abnormal waveforms.

CONCLUSION

Objective assessment of uterine artery waveforms using cut-off values of PI, A/C and (D - C)/B provides an estimation similar to that provided by subjective assessment by an experienced operator. These ratios will now need to be used prospectively in an unselected population to compare their screening properties.

Perioperative pharmacokinetics of transdermal fentanyl in elderly and young adult patients

The perioperative pharmacokinetics of transdermally-delivered fentanyl were compared in 10 young adult (mean [range] age 32.7, [25-38] yr) and eight elderly (mean [range] age 73.7 [64-82] yr) patients following abdominal surgery. Transdermal fentanyl patches designed to release 50 micrograms h-1 were applied 2 h preoperatively and left in place for 72 h. Plasma fentanyl concentrations were measured by radioimmunoassay during patch application and for 30 h after patch removal. The mean half-time (time for plasma concentrations to double after patch application) was 4.2 h in the younger group and 11.1 h in the elderly group (P < 0.005). Mean maximum plasma concentrations were 1.9 ng ml-1 and 1.5 ng ml-1 in the younger and elderly groups respectively (ns). There were no differences in the time at which maximum plasma concentrations occurred (tmax), elimination half-life after patch removal, or AUC(0-infinity).

Mitochondrial DNA in stroke and migraine with aura

Patients presenting with thrombotic stroke of unexplained etiology and or migraine with aura were screened for mitochondrial (mt) DNA mutations associated with cytopathies given that both migraine and stroke-like episodes are recognised with certain mt DNA mutations. Mutations usually associated with either mitochondrial encephalopathy, lactic acidosis and stroke-like episode, myoclonic epilepsy with ragged red fibres, or those strongly linked to Leber's hereditary optic neuropathy (LHON) were not detected in patients or controls. However, increased levels of two of the secondary LHON mutations were found. The T-->C mutation at nucleotide 4216 was more common than expected in patients aged 35 years or less, as was the 13708 G-->A mutation in young stroke patients. This data lends support to the possibility that an accumulation of minor mt DNA mutations may contribute to the pathoaetiology of stroke and migraine with aura in some young patients.

Fetal telemedicine: interactive transfer of realtime ultrasound and video via ISDN for remote consultation

Current referral practice for ultrasonically detected fetal abnormalities contributes to parental anxiety, inconvenience to patients, diagnostic inaccuracy, and general service inefficiency. To determine whether telemedicine would reduce these disadvantages, we established a 30-channel ISDN link between a district general hospital on an island and a subspecialty referral centre approximately 120 km away on mainland Britain. Live ultrasound images of the fetus were transmitted in realtime from a commercial scanner in the hospital using a total data transfer rate of 2 Mbit/s. After decompression at the receiving end, there was almost no perceptible loss of picture quality or frame rate. This report describes the technical aspects of the link and our preliminary experience with it. In the first two months of its operation, the link worked well and the consultants who used it found themselves confidently making diagnoses and carrying out counselling over it. If confirmed, the success of this technology has implications for future referral practice in fetal medicine.

Fetal telemedicine: six month pilot of real-time ultrasound and video consultation between the Isle of Wight and London

DESIGN

Prospective audit of first six months.

SETTING

Referral from a district general hospital on the Isle of Wight to a comprehensive tertiary referral service, the Centre for Fetal Care at Queen Charlotte's Hospital 120 km away in London.

PARTICIPANTS

Women whose pregnancy was suspected, or at risk, of fetal abnormality.

INTERVENTIONS

Remote consultation by transmitting ultrasound and video in real-time over ISDN 30 telephone lines. Contemporaneous questionnaire to referring practitioner and patient.

MAIN OUTCOME MEASURES

Frequency, indication, technical success and duration of consultation. Qualitative and semi-quantitative image quality. Effect of teleconsultation on need for physical referral.

RESULTS

Twenty-nine women underwent 39 teleconsultations, and image quality was sufficient for diagnosis in all but one. Fetal abnormalities were present in 76%. Referral in person was required for only four women, significantly fewer than the 13 the referring hospital indicated would have been physically referred in the absence of this service (P < 0.001). Most mothers were counselled by the specialist "face-to-face' over the link, and 80% felt teleconsultation reduced their anxiety.

CONCLUSIONS

A fetal telemedicine service is technically and clinically feasible. This demonstration suggests that such a service reduces the need for physical referral while increasing the rate of consultation, allowing better selection of patients who might benefit from referral. Further evaluation in a variety of clinical settings is now indicated, along with cost-benefit analysis.

Identification and characterization of transcripts from the biotin biosynthetic operon of Bacillus subtilis

Northern (RNA) blot analysis of the Bacillus subtilis biotin operon, bioWAFDBIorf2, detected at least two steady-state polycistronic transcripts initiated from a putative vegetative (Pbio) promoter that precedes the operon, i.e., a full-length 7.2-kb transcript covering the entire operon and a more abundant 5.1-kb transcript covering just the first five genes of the operon. Biotin and the B. subtilis birA gene product regulated synthesis of the transcripts. Moreover, replacing the putative Pbio promoter and regulatory sequence with a constitutive SP01 phage promoter resulted in higher-level constitutive synthesis. Removal of a rho-independent terminator-like sequence located between the fifth (bioB) and sixth (bioI) genes prevented accumulation of the 5.1-kb transcript, suggesting that the putative terminator functions to limit expression of bioI, which is thought to be involved in an early step in biotin synthesis.

Cerebral and renal artery blood flow velocity before and after birth

OBJECTIVE

To document perinatal changes in cerebral and renal artery haemodynamics in premature growth-retarded and normal term infants.

DESIGN

Longitudinal study of individual infants. Doppler ultrasound measurements of blood flow velocity (BFV) in the middle cerebral and renal arteries were obtained before delivery, soon after delivery and during the first week of postnatal life.

SETTING

Teaching hospital obstetric and neonatal units.

SUBJECTS

13 severely growth retarded infants born at 28-36 weeks gestation, and eight normally grown infants born at term.

RESULTS

In both groups, BFV in the cerebral artery was significantly lower in the first few hours after birth than in fetal life, but subsequently increased to reach pre-delivery values by the end of the first week. In contrast, BFV in the renal artery during the first postnatal day was not significantly different from fetal values, but it also increased during the subsequent week. In six of the preterm growth-retarded infants, fetal blood gases were measured in samples obtained by cordocentesis, and in these cases an increase in blood oxygen content at birth was documented.

CONCLUSIONS

Cerebral artery BFV falls at birth and is relatively low during the time that premature infants are at the greatest risk of developing periventricular haemorrhage.

Neuralgia after inguinal hernia repair

Severe chronic pain after groin hernia repair is uncommon but potentially debilitating. Fifteen patients with this condition were retrospectively reviewed. All patients had severe pain, which prevented their working or normal activity and was refractory to nonoperative treatment. Essentials of therapy included 1) a preoperative attempt to identify the involved nerve and 2) high ligation and division of the involved nerve identified at exploration. Twelve patients obtained excellent results and were able to return to normal activity with no requirement for analgesia. Understanding of the typical nerve anatomy, as well as the individual variation in nerve anatomy, can help prevent this complication and is essential for correction if the complication does develop.

Cloning, sequencing, and characterization of the Bacillus subtilis biotin biosynthetic operon

A 10-kb region of the Bacillus subtilis genome that contains genes involved in biotin-biosynthesis was cloned and sequenced. DNA sequence analysis indicated that B. subtilis contains homologs of the Escherichia coli and Bacillus sphaericus bioA, bioB, bioD, and bioF genes. These four genes and a homolog of the B. sphaericus bioW gene are arranged in a single operon in the order bioWAFDR and are followed by two additional genes, bioI and orf2. bioI and orf2 show no similarity to any other known biotin biosynthetic genes. The bioI gene encodes a protein with similarity to cytochrome P-450s and was able to complement mutations in either bioC or bioH of E. coli. Mutations in bioI caused B. subtilis to grow poorly in the absence of biotin. The bradytroph phenotype of bioI mutants was overcome by pimelic acid, suggesting that the product of bioI functions at a step prior to pimelic acid synthesis. The B. subtilis bio operon is preceded by a putative vegetative promoter sequence and contains just downstream a region of dyad symmetry with homology to the bio regulatory region of B. sphaericus. Analysis of a bioW-lacZ translational fusion indicated that expression of the biotin operon is regulated by biotin and the B. subtilis birA gene.

Common iliac artery flow velocity waveforms in fetuses with a single umbilical artery: a longitudinal study

OBJECTIVES

In fetuses with a single umbilical artery the entire blood flow to the placenta is transported through the common and internal iliac arteries from the side of the single artery, whereas the pelvic vessels from the side of the missing artery do not participate in the fetoplacental circulation. The aim of this study was to investigate the effect of gestational age on pelvic arterial blood flow in fetuses with single umbilical artery.

DESIGN

In 15 fetuses with a single umbilical artery (SUA), common iliac artery flow velocity waveforms were studied longitudinally using high resolution colour Doppler ultrasonography at three gestational ages: 18 to 20 weeks, 28 to 30 weeks, and 35 to 37 weeks. The pulsatility index was measured in each common iliac artery and mixed model analysis of variance was used to examine the effect of gestational age and side.

RESULTS

There was a highly significant difference in pulsatility index between common iliac arteries at all gestational ages, the values always being higher on the side that did not participate in the fetoplacental circulation (P < 0.001). For increasing gestation, the pulsatility index fell significantly in the SUA side but remained high in the non-SUA side (P < 0.001).

CONCLUSIONS

This study shows that the asymmetry in the pelvic arterial blood flow in fetuses with SUA increases as pregnancy progresses, consistent with decreasing vascular resistance in the placenta and increasing resistance in the lower extremities.

Effect of the addition of alfentanil to lignocaine during axillary brachial plexus anaesthesia

Peripheral administration of opioids has been suggested as a means of improving regional block. We studied 60 patients receiving axillary brachial plexus anaesthesia, allocated randomly to receive either normal saline 10 ml or normal saline 10 ml with alfentanil 10 micrograms/kg body weight through an axillary cannula. All patients received 1.5% lignocaine at a dose of 7 mg/kg body weight with adrenaline 1 in 200,000. The incidence of satisfactory block was similar in both groups. Although the percentage of patients with complete anaesthesia in the median nerve distribution was greater in the alfentanil group, there was no significant difference in any other distribution. The time to return of sensation and motor function was prolonged significantly in the alfentanil group (P < 0.05). After return of normal sensation, there was no significant difference between groups in postoperative analgesia. In a second part of the study, there was no significant increase in plasma concentrations of alfentanil in 10 patients given lignocaine and alfentanil, as outlined above. These observations suggest that alfentanil may have a peripheral local anaesthetic action.

Hydrostatic and osmotic pressure gradients produce manifestations of fetofetal transfusion syndrome in a computerized model of monochorial twin pregnancy

OBJECTIVE

In spite of recent advances in the assessment and treatment of fetofetal transfusion syndrome, its underlying mechanism remains controversial. We aimed to determine whether the clinical features of fetofetal transfusion syndrome could be explained by unidirectional or bidirectional intertwin transfusion along placental vascular anastomoses.

STUDY DESIGN

We constructed a dynamic computerized model of monochorial twin fetoplacental units on the basis of numerous interrelated hemodynamic, osmotic, and metabolic physiologic variables. The circulations were then linked by various combinations of direction and number of arteriovenous anastomoses.

RESULTS

With unidirectional anastomoses disease severity, characterized by disparity in blood solids, depended on donor arterial pressure but not on the number of anastomoses. In the chronic state water movement resulting from raised osmotic pressure in the recipient and reduction in the donor produced hydroosmotic pressure equilibrium, reducing anastomotic flow to near zero. Atrial natriuretic peptide-driven urine production was markedly increased in the recipient because of the raised vascular hydrostatic pressure component. With bidirectional anastomoses recirculation between twins reduced discordancy in colloids and hematocrit, and the clinical picture was determined by the degree of asymmetry in the number of connections.

CONCLUSIONS

Severe manifestations of fetofetal transfusion syndrome can be explained by unidirectional intertwin transfusion and lesser degrees by asymmetric bidirectional transfusion.

Discordant blood flow velocity waveforms in left and right brachial arteries in growth-retarded fetuses

OBJECTIVE

To determine if the increase in cerebral blood flow ("brain-sparing" effect) with fetal hypoxemia is associated with discordant hemodynamics in the upper extremities.

METHODS

We studied 12 fetuses with severe growth retardation, absent or reverse end-diastolic blood flow in the umbilical artery, and low pulsatility index (PI) in the middle cerebral artery, and 12 appropriately grown control fetuses with normal fetoplacental Doppler studies. The right and left brachial arteries were identified by high-resolution color Doppler ultrasonography, and the PI was measured in each brachial artery.

RESULTS

All growth-retarded fetuses had lower impedance indices in the right than in the left brachial artery (mean delta PI 1.0, 95% confidence interval [CI] 0.7-1.3, P < .001). No differences in the brachial artery impedance indices were found in control fetuses matched for gestational age (mean delta PI 0.0, 95% CI -0.2 to 0.2).

CONCLUSIONS

Left and right brachial artery blood flow velocity waveforms are discordant in fetuses with growth retardation and cerebral vasodilation. Because the right arm receives its blood supply from the same source as the brain (brachiocephalic artery) and given the proximity of the left subclavian artery to the ductus arteriosus, we speculate that this might be the result of increased blood flow into the brachiocephalic circulation and/or functional differences in the distribution of left and right ventricular output within the aortic arch in response to fetal hypoxemia.

Follicular fluid levels of midazolam, fentanyl, and alfentanil during transvaginal oocyte retrieval

OBJECTIVE

To investigate the time course of changes in follicular fluid (FF) concentrations of midazolam (Roche Products Ltd., Welwyn Garden City, United Kingdom), fentanyl (Janssen Pharmaceuticals Ltd., Wantage, United Kingdom), and alfentanil (Janssen Pharmaceuticals Ltd.) during ultrasound-guided transvaginal oocyte collection.

STUDY DESIGN

Forty-five patients with tubal infertility were randomized to receive a bolus IV dose of midazolam, fentanyl, or alfentanil for sedation during ultrasound-guided transvaginal oocyte collection. Paracervical block with lignocaine was given for analgesia. Simultaneous blood and FF samples were drawn at 5-minute intervals after the bolus dose for analysis of drug levels.

RESULTS

Data were obtained on 15 women receiving midazolam and fentanyl and on 13 women receiving alfentanil. Plasma levels of all agents rose to a peak and then fell in an exponential fashion as was expected. The FF levels of the agents continued to rise significantly to 25 minutes after the bolus dose, although the absolute level was low when compared with the blood level. There were no significant differences in fertilization or pregnancy rates in the three groups, but patient numbers were small.

CONCLUSION

We conclude that midazolam, fentanyl, and alfentanil are found in FF after a single IV dose, but further investigation needs to be undertaken to investigate any potential influence on fertilization and implantation rates.

Acute maternal hydration in third-trimester oligohydramnios: effects on amniotic fluid volume, uteroplacental perfusion, and fetal blood flow and urine output

OBJECTIVE

Our purpose was to determine whether acute maternal hydration in pregnancies with third-trimester oligohydramnios (1) increases amniotic fluid index and hourly fetal urine production rate and (2) alters uteroplacental perfusion and fetal blood flow.

STUDY DESIGN

Ten women with third-trimester oligohydramnios (amniotic fluid index < or = 5 cm) and 10 controls with normal amniotic fluid volume (amniotic fluid index > 7 cm) were prospectively recruited for this study. Maternal plasma and urine osmolality, amniotic fluid index, hourly fetal urine production rate, and Doppler flow velocimetry of maternal uterine artery and fetal umbilical, descending aorta, middle cerebral, and renal arteries were determined before and after oral hydration by having the patient drink 2 L of water over 2 hours.

RESULTS

There was a significant reduction in maternal plasma (p < 0.05) and urine osmolality (p < 0.0001) in both groups after short-term oral hydration. Hydration increased amniotic fluid volume in women with oligohydramnios (mean change in amniotic fluid index 3.2 cm, 95% confidence intervals 1.1 to 5.3; p < 0.02) but not in those with normal amniotic fluid volume (mean change in amniotic fluid index -2.0, 95% confidence intervals -4.1 to +0.2). The hourly fetal urine production rate, however, did not increase in either group (mean change in hourly fetal urine production rate 3.5 ml/hr, 95% confidence intervals -11.7 to +18.7 and -6.8 ml/hr, 95% confidence intervals -2.9 to -10.7, respectively). Hydration was associated with an increase in uterine artery mean velocity in the oligohydramnios group (mean change in mean velocity 16.7 cm/sec, 95% confidence intervals 8.0 to 25.3; p < 0.006) but not in controls (mean change in mean velocity 1.2 cm/sec, 95% confidence intervals -19.7 to +22.1). There was no change in pulsatility index or in velocity in any of the fetal vessels studied in either group.

CONCLUSIONS

Short-term maternal oral hydration increases the amniotic fluid index in women with third-trimester oligohydramnios. Although the mechanism for this effect remains unclear, it could not be accounted for by fetal urination in this study but instead was associated with improved uteroplacental perfusion.

Ablation of acardiac twin by alcohol injection into the intra-abdominal umbilical artery

BACKGROUND

Twin reversed arterial perfusion sequence is a rare complication of monochorionic twinning, in which the normal pump twin perfuses the abnormal acardiac twin in a reversed fashion via an artery-to-artery placental anastomosis. Mortality in the normal twin exceeds 50% as a result of preterm labor, polyhydramnios, and congestive heart failure.

CASE

A twin pregnancy complicated by the twin reversed arterial perfusion sequence developed early hemodynamic decompensation in the pump twin with increasing size of the acardiac twin. Ablation of the acardiac twin at 23 weeks' gestation was achieved successfully by injecting 1 mL of absolute alcohol into the intra-abdominal portion of the single umbilical artery.

CONCLUSION

Direct ultrasound-guided intravascular injection of absolute alcohol is an easy and straightforward technique to occlude circulation to the acardiac twin. This vessel can be identified easily by color Doppler ultrasonography away from the main venous trunk. Selection of this target, rather than occlusion at the level of the umbilical cord, could reduce the risks of cord accidents and inadvertent intravenous injection of the ablative material.

Early prenatal diagnosis of holoprosencephaly: the value of transvaginal ultrasonography

Holoprosencephaly is a rare condition characterized by different degrees of fused ventricles resulting from the failure of the prosencephalon to cleave during embryonic life. In this report we present a case of alobar holoprosencephaly diagnosed prenatally at 15 weeks' gestation in a woman with a family history of open neural tube defect. The diagnosis was initially missed because only suboptimal views of the fetal brain were obtained with transabdominal ultrasonography due to fetal position; however, a better depiction of brain anatomy was obtained using the transvaginal approach, allowing the detection of a single ventricle and fused thalami. We conclude that transvaginal ultrasonography is not only important for the early prenatal diagnosis of central nervous system abnormalities but also for enhancing brain visualization when transabdominal examination of the fetal head is limited due to maternal and fetal factors.

Recovery and relapse in adolescents with bipolar affective illness: a five-year naturalistic, prospective follow-up

OBJECTIVE

This study was a 5-year naturalistic prospective follow-up of 54 consecutive admissions of adolescents to a university inpatient service with a diagnosis of bipolar I affective illness.

METHOD

Subjects received structured clinical evaluations every 6 months after entry to establish time to recovery and subsequent relapse. Regression models were used to identify predictors of differential course.

RESULTS

Rate of recovery varied by polarity of episode at time of entry, with quick recovery observed in subjects with pure mania or mixed states, and a protracted index episode in subjects with pure depression. Multiple relapses were most often seen in subjects with mixed or cycling episodes at intake.

CONCLUSIONS

Polarity of illness may have utility in identifying bipolar adolescents with a more recurrent illness. Comparison with adult data suggests that recurrence risks may vary as a function of age at onset or stage of the disease process.

Cloning and characterization of the Bacillus subtilis birA gene encoding a repressor of the biotin operon

The Bacillus subtilis birA gene, which regulates biotin biosynthesis, has been cloned and characterized. The birA gene maps at 202 degrees on the B. subtilis chromosome and encodes a 36,200-Da protein that is 27% identical to Escherichia coli BirA protein. Three independent mutations in birA that lead to deregulation of biotin synthesis alter single amino acids in the amino-terminal end of the protein. The amino-terminal region that is affected by these three birA mutations shows sequence similarity to the helix-turn-helix DNA binding motif previously identified in E. coli BirA protein. B. subtilis BirA protein also possesses biotin-protein ligase activity, as judged by its ability to complement a conditional lethal birA mutant of E. coli.

Postoperative analgesia with transdermal fentanyl following lower abdominal surgery

In a randomised, placebo-controlled, double-blind study involving 81 patients undergoing total abdominal hysterectomy, the postoperative analgesia provided by transdermal fentanyl given at 25, 50, or 75 micrograms.h-1 for 72 h was compared with a placebo group. The efficacy of the Transdermal Therapeutic System was related to the rate of fentanyl delivery, higher rates being associated with significantly lower visual analogue pain scores (24, 20, 17 and 13, for placebo, 25, 50 and 75 micrograms.h-1 respectively) and reduced patient controlled analgesia morphine requirements (44, 38, 33 and 31 mg respectively). Patients' overall sedation scores were not increased by transdermal fentanyl, but respiratory rates decreased with higher transdermal fentanyl dosage.

True knot of the umbilical cord: a difficult prenatal ultrasonographic diagnosis

We examined retrospectively the use of ultrasonography in 18 cases in which a true knot of the umbilical cord was found at delivery. All women had a normal second-trimester scan in which no cord abnormality was detected. Thirteen (72%) also had third-trimester color Doppler ultrasonography, at which time the cord anomaly was again missed. In one of these cases the diagnosis could have been made with color flow imaging, but the abnormal pattern was mistaken instead for multiple loops of cord. On the other hand, the diagnosis of true knot was considered prenatally in two cases, but not confirmed at delivery, when only a prominent false knot was found in one and a normal cord in the other. We conclude that true knots of the umbilical cord do not have a characteristic appearance in utero and therefore are easily missed at routine prenatal ultrasonography.

Third-trimester hyperechogenic bowel in Down syndrome

The association between second-trimester hyperechogenic bowel and Down syndrome has been well established in the literature. In this report we present a case of Down syndrome in which this finding was only detected during the third-trimester scan, after normal bowel echogenicity was documented in the second trimester. This report suggests that hyperechogenic bowel could be a late manifestation of Down syndrome.

Filtration of fentanyl is not the cause of the elevation of arterial blood pressure associated with post-bypass ultrafiltration in children

Modified ultrafiltration after cardiopulmonary bypass in children has been shown to be associated with an increase in arterial blood pressure. As part of a series of studies to investigate the possible causes of this blood pressure elevation, the hypothesis that if filtration was removing a significant amount of fentanyl, then the increase in blood pressure might be due to pain was proposed. Ten children, aged between 0.5 and 9.3 years (median 3.8 years), weighing 5.9 to 25.5 kg (median 15.7 kg), underwent corrective cardiac surgery (incorporating modified ultrafiltration). A standard anesthetic protocol was followed, with up to 78 micrograms/kg of fentanyl given prebypass for analgesia. After completion of cardiopulmonary bypass, modified ultrafiltration was commenced at 100 mL/min until a hematocrit of 35% was reached. Samples were taken of arterial blood (prefiltration, 3, 10, and 20 minutes postfiltration), the venous reservoir blood (prefiltration) and the filtrate (5 and 10 minutes into filtration). Hemodynamic data were recorded both prefiltration and postfiltration. The hemodynamic data showed the expected rise in both systemic arterial pressure and cardiac index after ultrafiltration. The plasma fentanyl concentrations did not significantly change after ultrafiltration: 1.59 to 12.39 ng/mL (median 6.27 ng/mL) prefiltration and 2.05 to 15.59 ng/mL (6.29 ng/mL) at 3 minutes, 2.22 to 12.64 ng/mL (6.87 ng/mL) at 10 minutes, and 1.83 to 11.52 ng/mL (5.85 ng/mL) at 20 minutes postfiltration.(ABSTRACT TRUNCATED AT 250 WORDS)

Discordant iliac and femoral artery flow velocity waveforms in fetuses with single umbilical artery

OBJECTIVE

The aim of this study was to investigate pelvic and femoral arterial flow velocity waveforms in fetuses with a single umbilical artery.

STUDY DESIGN

Seven fetuses with single umbilical artery and no other ultrasonographically detected anomalies were studied with color Doppler ultrasonography at a median gestational age of 24 weeks (range 18 to 34 weeks). Flow velocity waveforms from the relevant vessels were obtained as follows: (1) umbilical artery from a free loop of cord, (2) common iliac artery from both sides just below the aortic bifurcation, (3) internal iliac artery and intraabdominal portion of the umbilical artery from the vessel visualized alongside the fetal bladder, and (4) femoral artery on both sides from the upper third of the fetal thigh. The pulsatility index was measured, and comparisons were made with the paired t test. A p value < 0.05 was considered significant.

RESULTS

The pulsatility index in the umbilical artery was normal in all cases. There were highly significant differences between the common iliac arteries in each side (difference in pulsatility index 2.7, 95% confidence interval 2.0 to 3.5, p < 0.001). Significant differences between both femoral arteries were also noted (difference in pulsatility index 1.0, 95% confidence interval 0.3 to 1.7, p < 0.001). In both vessels the pulsatility index was always higher in the side that did not participate in the placental circuit.

CONCLUSION

This study demonstrates that fetuses with single umbilical artery have asymmetric arterial blood flow patterns in the pelvic and lower extremities.

Human maternal uniparental disomy for chromosome 16 and fetal development

Two severely growth-retarded fetuses found to have maternal uniparental disomy (UPD) for chromosome 16 and trisomy 16 placental mosaicism both had an unfavourable outcome. Antenatally, the first case was complicated by an unexplained raised maternal serum alpha-fetoprotein concentration, preterm premature rupture of the membranes, and growth retardation detectable at 21 weeks' gestation, whilst the other had an unexplained raised maternal serum human chorionic gonadotrophin level, a two-vessel cord on ultrasound, and cessation of growth at 25 weeks. At post-mortem, both babies had an imperforate anus. Fetal maternal UPD may explain the poor outcome that occurs in some cases of confined placental mosaicism for chromosome 16 and is also associated with specific fetal abnormalities.

Fetal hyperechogenic bowel following intra-amniotic bleeding

OBJECTIVE

To test the hypothesis that increased echogenicity of the fetal bowel at second-trimester scans results from intra-amniotic bleeding.

METHODS

We studied 726 patients undergoing second-trimester amniocentesis for advanced maternal age. Three groups were identified according to the color of the amniotic fluid (AF) obtained: clear fluid, blood-stained fluid, and dark brown fluid. Two to 4 weeks after the amniocentesis, all patients had a targeted ultrasound examination for the detection of fetal structural anomalies and markers of chromosomal abnormalities, which included a survey of the fetal bowel. The incidence of hyperechogenic bowel in each group was compared by Fisher exact test. P < .05 was considered significant.

RESULTS

In 694 cases, the AF was clear (95%), in 20 blood-stained (3%), and in 12 dark brown (2%). Hyperechogenic bowel was detected in 14 fetuses with clear fluid (2%), in two with blood-stained fluid (10%), and in three with dark brown fluid (25%). Fetuses with proven intra-amniotic bleeding (ie, dark brown or blood-stained AF at amniocentesis) had a significantly higher incidence of hyperechogenic bowel compared to those with clear AF (five of 32 [15.6%] and 14 of 694 [2.0%], respectively; P < .001, 95% confidence interval for the difference in proportions 6.3-17.6%).

CONCLUSIONS

Our study demonstrates that intra-amniotic bleeding is associated with an increased incidence of fetal hyperechogenic bowel at second-trimester ultrasound scans. This sonographic phenomenon may be due to the presence of blood in the fetal bowel caused by fetal swallowing of bloody AF.

Long-term prognosis of transient lone bilateral blindness in adolescents and young adults

We describe a group of 14 patients aged 8-38 years at presentation who had one or more sudden transient attacks of bilateral blindness. Eight patients described bilateral blindness as their only symptom whereas six others experienced some mild associated symptoms. Visual loss always developed within seconds and attacks were often precipitated by exercise, stress, or postural change. Of 13 patients available for review, none suffered a major vascular event during a mean follow up of 10 years. When adolescents and young adults present with transient bilateral blindness, investigations are unlikely to reveal a cause and the long-term prognosis appears benign.

The value of color Doppler ultrasound in the prenatal diagnosis of hypoplastic umbilical artery

The prenatal diagnosis of hypoplastic umbilical artery has recently been reported, based on the visualization of discordant size between both umbilical arteries in association with discordant umbilical artery flow velocity waveforms. In this report we present two cases of hypoplastic umbilical artery and describe the use of color flow imaging and Doppler ultrasound in the prenatal evaluation of this condition. The principal advantages of these techniques include the confirmation of blood flow within the hypoplastic artery, thus ruling out the possibility of an atrophic non-functional artery, and the demonstration of size discrepancy at the level of the intra-abdominal portion of the umbilical arteries, validating the intra-amniotic cord findings. Color Doppler ultrasound is an important tool for diagnosing and evaluating vascular anomalies affecting the umbilical cord.

Doppler ultrasound screening as part of routine antenatal scanning: prediction of pre-eclampsia and intrauterine growth retardation

OBJECTIVE

To assess the value of incorporating continuous wave Doppler ultrasound of the uterine arteries into the routine scan as a screening test in an unselected population.

DESIGN

A cross sectional study by multiple operators using continuous wave Doppler ultrasound to obtain flow velocity waveforms (FVW) from both uterine arteries of all women attending for routine anomaly scan at 18 to 22 weeks over a period of 12 months. An abnormal FVW in either uterine artery was used to predict intrauterine death, antepartum haemorrhage and three different degrees of severity of pre-eclampsia and growth retardation, singly and in combination.

SETTING

King's College Hospital, London.

SUBJECTS

Two thousand, four hundred and thirty women attending for routine anomaly ultrasound scan.

RESULTS

A total of 2430 women were scanned with a 90% follow up rate. The results demonstrate higher sensitivities than previous studies, but with a high proportion of false positive tests. By including an early diastolic notch in the definition of an abnormal FVW the prediction of pre-eclampsia is markedly improved; the relative risk to a woman with an abnormal waveform of developing moderate or severe pre-eclampsia is increased 24-fold. Although the positive predictive value for babies less than the 5th centile for gestation is only 15%, those at risk of neonatal complications may be identified.

CONCLUSION

This simple test can be performed at a routine visit and a group of women can be identified for further assessment and possible therapeutic intervention.