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Biomedical subjects

J C Dornan

Publications and source records attributed to J C Dornan.

At least 19 recordsLinked to original sources
PubMed1999

Incidence and risk factors for ventricular septal defect in "low risk" neonates.

AIMS: To quantify the incidence of ventricular septal defect in "low-risk" neonates; and to define any associated risk factors. METHODS: One hundred and seventy three patients with ventricular septal defects from a scanned population of 3971 clinically normal neonates were compared with scanned controls, considered to be clinically normal. A subset of the group with defects was compared with normal infants delivered over the same period, to identify any seasonal variation. RESULTS: Ventricular septal defects were detected in 4.36 % of the "scanned" group (173 out of 3971). Ten had perimembranous defects and the remainder apical or muscular lesions. Eleven neonates had multiple defects. The incidence of ventricular septal defect was independent of most tested risk factors. There were significantly more girls in the group with defects compared with the controls (p = 0.004). The defects group also contained fewer infants born during summer months (p = 0.04). CONCLUSIONS: The incidence of ventricular septal defects was much higher than might be expected, given that "high risk infants" were excluded. The observations that gender and season of birth affect the rate suggest that both genetic and environmental factors may be involved in the aetiology.

Heart Septal Defects, Ventricular↗
PubMed1998

Early amniocentesis: effect of removing a reduced volume of amniotic fluid on pregnancy outcome.

In mid-trimester amniocentesis (MTA), 12-15 ml of amniotic fluid is aspirated for cytogenetic analysis. When a similar volume of amniotic fluid is removed by early amniocentesis (EA), it represents a significant proportion of the total amniotic fluid volume in the first trimester. The fluid depletion, which may persist for 7 to 10 days, is considered to impair development of fetal lungs and extremities and, possibly, contribute towards procedure-related congenital abnormalities and miscarriages. By only removing 7 ml of amniotic fluid, we have demonstrated a total miscarriage rate (3.8 per cent) comparable with previous large studies (Table V), a low incidence of respiratory difficulties at birth (2.7 per cent) and a low incidence of fixed flexion deformities (1.6 per cent), at the expense of a small increase in the incidence of culture failure (2.2 per cent).

Abortion, Spontaneous↗
PubMed1998

Transplacental early amniocentesis and pregnancy outcome.

The effect on pregnancy outcome of transplacental needle insertion was studied in 401 consecutive women attending for early amniocentesis between 10 and 14 completed weeks of pregnancy. Transplacental early amniocentesis was associated with a significantly higher incidence (P < 0.001) of blood-stained amniotic fluid taps but a lower incidence (not significant; P > 0.05) of pregnancy loss and miscarriages. Women in the nontransplacental early amniocentesis group had a significantly higher (P < 0.01) incidence of late procedure-related antenatal complications, such as preterm rupture of membranes or preterm labour. Our study showed that transplacental early amniocentesis is a safe procedure; contrary to present recommendations, the study also showed that avoiding the placenta during early amniocentesis is an unnecessary practice.

Amniocentesis↗
PubMed1997

Transabdominal cervicoisthmic cerclage: initial experience.

Pregnancy outcome before and after insertion of transabdominal cervical cerclage is evaluated. The series also reports on the first cases of second pregnancies with the original suture left in situ. It is our view that transabdominal cervical cerclage should only be performed in units that have specialists in Perinatal Medicine.

Cervix Uteri↗
PubMed1996

Is evening primrose oil of value in the treatment of premenstrual syndrome?

A systematic literature search of clinical trials of evening primrose oil (EPO) for the treatment of the premenstrual syndrome (PMS) was carried out with a view to performing a meta-analysis. Only seven placebo-controlled trials were found but only in five trials was randomization clearly indicated. Inconsistent scoring and response criteria made statistical pooling and hence a rigorous meta-analysis inappropriate. The two most well-controlled studies failed to show any beneficial effects for EPO, although because the trials were relatively small modest effects cannot be excluded. Nonetheless, on current evidence EPO is of little value in the management of premenstrual syndrome.

Clinical Trials as Topic↗
PubMed1994

Clinical trials of treatments of premenstrual syndrome: entry criteria and scales for measuring treatment outcomes.

OBJECTIVE: To demonstrate similarities and differences between the various instruments used by clinical trialists for measurement of premenstrual syndrome to encourage development of consensus of measurement to aid future research. DESIGN: Computer and manual searches of all trials of drugs used for premenstrual syndrome supplemented by retrieval of all questionnaires and scales cited. Letters were sent to the main manufacturers to identify trials not in the public domain. MAIN OUTCOME MEASURES: Number of scales in current use for classifying premenstrual syndrome; the symptoms included within them; their organisation of symptoms into clusters; the numerical values used in the scaling; the most frequently used items; and the extent of overlap in the criteria used. RESULTS: Three hundred and fifty clinical trials of 115 different drugs were identified. The most common symptoms or signs used in the scales were (frequency in square brackets) irritability [44], headache or migraine [40], depression [37], tearfulness [34], tension [31], anxiety [31], breast tenderness [31], mood swings or lability [30], back pain [30], weight gain [29], abdominal bloating [28], lack of concentration [28], food craving [28], and increased appetite [26]. Sixty-five different questionnaires or scales were used to classify premenstrual syndrome and for assessing entry eligibility and treatment outcomes; of these 65, 47 included sufficient details for a formal analysis and 18 scales grouped the symptoms or items into clusters or subgroups. CONCLUSION: There is wide diversity in the scales used for assessing entry eligibility and treatment outcomes in premenstrual syndrome. This makes comparative evaluation of possible treatments extremely complex and difficult. It is recommended that authorities and organisations involved in conducting trials of treatments for premenstrual syndrome develop a consensus statement about the best instrument to be used. Regulatory authorities could perhaps provide guidance to which scales they would accept when clinical trials of drugs for premenstrual syndrome are submitted to them for assessment. This would ensure that industry-sponsored trials provide objective data. Consensus is required given the poor performance of most current treatments of premenstrual syndrome.

Clinical Trials as Topic↗
PubMed1992

Antenatal detection of renal abnormalities.

The aim of this retrospective study is to assess the value of routine ultrasonography in the detection of renal abnormalities. Twenty-nine pregnancies (one set of twins) with suspected renal abnormalities (i.e. renal cystic spaces, oligohydramnios or hyperechoic kidneys) were delivered over a two year period (1.8.1987-31-7-1989) in a unit where 90% of pregnancies (6,562) were scanned routinely at 18-20 weeks gestation or later, if booking for confinement was delayed. In pregnancies with suspected anomalies prenatal ultrasound was performed monthly until 28 weeks and fortnightly until delivery. Non survivors [5] had histological or postmortem examination. Liveborn infants [25] had renal ultrasonography in the neonatal period and paediatric follow-up if abnormal. Sixteen (53%) of the 30 cases (one set of twins) suspected of renal abnormalities by routine prenatal ultrasonography had renal anomalies confirmed postnatally. Five women were non survivors, all of which had associated anomalies. In the eleven survivors the diagnoses were pelvi-ureteric junction obstruction [6], renal dysplasia [2], vesicoureteric reflux [2] and suspected ureterocele [1]. Fourteen infants with pelvicalyceal dilatation had normal postnatal renal ultrasound. Although abnormal prenatal renal ultrasound is a useful indicator of postnatal disease and aids decisions on the management of pregnancy, further large collaborative studies with extended paediatric follow-up are required to assess the significance of pelvicalyceal dilatation.

Female↗
PubMed1992

Neural tube defects--prenatal diagnosis and management.

Neural tube defects rank second to congenital heart disease as a major cause of congenital malformation. Recent developments in ultrasound have improved prenatal diagnosis. Due to anomaly scans at 18 weeks gestation and the availability of a genetic clinic, prenatal diagnosis of neural tube defects at the Royal Maternity Hospital was 91.2% during 1987-1989. However, only 50% of parents accept termination of pregnancy and it is questionable if prenatal diagnosis is of benefit to those who wish to continue with the pregnancy. Parents may accept the situation better at birth, having had time to come to terms with it, helped with support from the obstetrician, clinical geneticist, paediatrician, genetic nurse and social worker. For some affected fetuses who have better muscle function and leg movement at term it appears from the literature that the outcome may be improved by caesarean section delivery. In Ireland fetuses with neural tube defects will continue to be delivered, as termination is unacceptable to many, but despite this there may be a positive benefit from prenatal diagnosis of neural tube defects. Prospective randomised controlled trials are needed to confirm benefit from delivery by caesarean section for fetuses with a good prognosis. As a result of prenatal diagnosis of a neural tube lesion the fetus should enjoy benefit in terms of physical morbidity, and the parents should benefit in terms of psychological morbidity.

Abortion, Induced↗
PubMed1990

Early amniocentesis: experience of 222 consecutive patients, 1987-1988.

Early amniocentesis from 9 to 14 weeks' gestation provides a safe and accurate method of prenatal diagnosis of cytogenetic and biochemical disorders. There was a 100 per cent success rate in culturing the amniotic cells from 222 samples obtained between 9 and 14 weeks' gestation. Follow-up of the patients to delivery revealed an abortion rate of 1.4 per cent. Among the 207 live- and stillborn infants, only one had a congenital abnormality (bilateral talipes equino-varus) and no infant had respiratory distress syndrome or pneumonia. Eleven pregnancies were terminated following the detection of a chromosomal, biochemical, or congenital abnormality (5.0 per cent). However, before the procedure of early amniocentesis becomes routine clinical practice, it requires appraisal by a randomized clinical trial.

Amniocentesis↗
PubMed1989

Antenatal screening for intrauterine growth retardation with umbilical artery Doppler ultrasonography.

To assess the usefulness of continuous wave Doppler ultrasonography as an antenatal screening tool for the detection of intrauterine growth retardation and fetal compromise 2097 singleton pregnancies were studied. Umbilical artery velocity waveforms were obtained at 28, 34, and 38 weeks of gestation, from which the pulsatility index, A/B ratio, and resistance parameter were calculated. No abnormal features or indices of neonatal outcome were adequately predicted. The most sensitive index for being delivered of a growth retarded infant (less than 5th centile birth weight for gestation) was an A/B ratio at 34 weeks (sensitivity 40%, specificity 84%). Other measures that show poor neonatal nutritional state (ponderal index, skinfold thickness, and ratio of mid-arm circumference to head circumference) were even less well predicted. Acute and chronic hypoxia as determined by Apgar score, pH in blood from the cord artery, and packed cell volume correlated poorly with umbilical artery waveform indices, and there was no obvious difference between the indices of those who subsequently required operative or instrumental delivery for fetal distress and those requiring no intervention. There were three unexplained stillbirths in the series, in each of which the fetus had shown waveform patterns that suggested increased peripheral resistance, though the technique did not appear to be useful for predicting the time of subsequent death. Screening for small for dates babies in a three stage programme was of no value regardless of the threshold or index chosen. Obstetricians should resist the temptation to introduce screening with Doppler ultrasonography until its proper role has been determined.

Birth Weight↗
PubMed1988

Pregnancy complicated by maternal heart disease. A review of 519 women.

Between 1970 and 1983, 519 pregnancies in 405 women with heart disease were managed at the Royal Maternity Hospital, Belfast, Northern Ireland, a rate of 1.3 per 100 deliveries. In 312 (60%) the heart disease was of rheumatic origin, in 161 (31%) congenital, and the remaining 46 (9%) were a miscellaneous group that included arrhythmias, ischaemic heart disease and cardiomyopathies. The New York Heart Association (NHYA) grading was no greater than 1-2 in 445 (86%) pregnancies antenatally. Three maternal deaths occurred, all in the group whose antenatal NYHA grade was 3-4. Heart failure was present in 96 (18%) pregnancies antenatally, and six others developed failure during labour or in the puerperium. Prophylactic antibiotics were not used routinely and infective endocarditis did not occur. The perinatal mortality rate was 19/1000, and the rate of congenital malformations was not raised in the reviewed group.

Adult↗
PubMed1985

The capillary plexus in the gas exchange zone of human neonatal lung: an ultrastructural study.

The structure of the capillary plexus in the gas exchange zone in the lungs of five neonates was investigated by electron microscopy and cytochemical techniques. The results show that the capillaries associated with the terminal respiratory saccules are narrow and that they generally possess two to three endothelial cells per cross section. "Seamless" and protoplasmic capillaries were not observed. A capillary plexus was located on either side of each intersaccular septum and the mesh size of this plexus was relatively large. The gas diffusion pathway in the neonatal lung was found to be very short (mean 1.84 micron). It is suggested that the layer of periodate reactive material lining the luminal surfaces of the capillary endothelial cells may have important functions in vivo.

Capillaries↗