Phillipa M. Kyle

Prediction of adverse maternal outcomes in pre-eclampsia: development and validation of the fullPIERS model

BACKGROUND Pre-eclampsia is a leading cause of maternal deaths. These deaths mainly result from eclampsia, uncontrolled hypertension, or systemic inflammation. We developed and validated the fullPIERS model with the aim of identifying the risk of fatal or life-threatening complications in women with pre-eclampsia within 48 h of hospital admission for the disorder. METHODS We developed and internally validated the fullPIERS model in a prospective, multicentre study in women who were admitted to tertiary obstetric centres with pre-eclampsia or who developed pre-eclampsia after admission. The outcome of interest was maternal mortality or other serious complications of pre-eclampsia. Routinely reported and informative variables were included in a stepwise backward elimination regression model to predict the adverse maternal outcome. We assessed performance using the area under the curve (AUC) of the receiver operating characteristic (ROC). Standard bootstrapping techniques were used to assess potential overfitting. FINDINGS 261 of 2023 women with pre-eclampsia had adverse outcomes at any time after hospital admission (106 [5%] within 48 h of admission). Predictors of adverse maternal outcome included gestational age, chest pain or dyspnoea, oxygen saturation, platelet count, and creatinine and aspartate transaminase concentrations. The fullPIERS model predicted adverse maternal outcomes within 48 h of study eligibility (AUC ROC 0·88, 95% CI 0·84-0·92). There was no significant overfitting. fullPIERS performed well (AUC ROC >0·7) up to 7 days after eligibility. INTERPRETATION The fullPIERS model identifies women at increased risk of adverse outcomes up to 7 days before complications arise and can thereby modify direct patient care (eg, timing of delivery, place of care), improve the design of clinical trials, and inform biomedical investigations related to pre-eclampsia. FUNDING Canadian Institutes of Health Research; UNDP/UNFPA/WHO/World Bank Special Programme of Research, Development, and Research Training in Human Reproduction; Preeclampsia Foundation; International Federation of Obstetricians and Gynecologists; Michael Smith Foundation for Health Research; and Child and Family Research Institute.

Prediction of chorionicity in twin pregnancies at 10–14 weeks of gestation

Objective To examine the accuracy of sonographic determination of chorionicity in twin pregnancies at 10–14 weeks of gestation.

Current CHS and NHBPEP Criteria for Severe Preeclampsia Do Not Uniformly Predict Adverse Maternal or Perinatal Outcomes

Objective: To determine the association between adverse maternal/perinatal outcomes and Canadian and U.S. preeclampsia severity criteria. Methods: Using PIERS data (Preeclampsia Integrated Estimate of RiSk), an international continuous quality improvement project for women hospitalized with preeclampsia, we examined the association between preeclampsia severity criteria and adverse maternal and perinatal outcomes (univariable analysis, Fishers exact test). Not evaluated were variables performed in <80% of pregnancies (e.g., 24-hour proteinuria). Results: Few of the evaluated variables were associated with adverse maternal (chest pain/dyspnea, thrombocytopenia, ‘elevated liver enzymes’, HELLP syndrome, and creatinine >110 μM) or perinatal outcomes (dBP >110 mm Hg and suspected abruption) (at p < 0.01). Conclusions: In the PIERS cohort, most factors used in the Canadian or American classifications of severe preeclampsia do not predict adverse maternal and/or perinatal outcomes. Future classification systems should take this into account.

Analysis of outcome in hydrops fetalis in relation to gestational age at diagnosis, cause and treatment.

Objective. To examine fetal outcome in hydrops fetalis in relation to gestational age at diagnosis and following investigation and treatment.

Prenatal Sonographic Features of Congenital Lobar Emphysema

The prenatal sonographic features of congenital lobar emphysema (CLE) have not been well characterised. Five cases have been reported in the literature and on all these occasions either an echogenic (3) or a cystic (2) lung lesion was detected prenatally and the diagnosis was confirmed after the operation. This is the sixth case of CLE in the literature with prenatal sonographic features documented. The prenatal scans of a 23-year-old lady performed at 22 weeks of gestation revealed cystic lesions and increased echogenicity of the right fetal lung. There were no other anomalies and the karyotype was normal. The lesion decreased in size at 28 weeks and the baby was born by a normal vaginal delivery at 41 weeks. CT scan performed on day 6 confirmed cystic changes on the right lung with compression of the right lower lobe. A repeat CT scan performed at 4 months revealed extensive cystic changes in a hyper-inflated right lung and mediastinal shift to the left. At operation, abnormally inflated right upper and middle lobes were found suggesting a CLE. There were no subsequent complications after removal and histology confirmed CLE. The reported cases are reviewed and the prenatal sonographic features of CLE are discussed.

Comparison of methods to identify significant proteinuria in pregnancy in the outpatient setting

The efficacy of the albumin/creatinine ratio (ACR) measurement in detection of significant proteinuria when performed in a high‐risk antenatal clinic was compared with automated dipstick, protein/creatinine ratio (PCR), and 24‐hour urine protein measurements. Both the ACR (DCA 2000) and PCR were strongly predictive for the presence or absence of significant proteinuria, with positive likelihood ratios (LRs) of 27.4 and 31.6 and negative LRs of 0.0 and 0.1, respectively. Both the ACR (DCA 2000) and PCR are effective tests for both identifying and excluding significant proteinuria in the outpatient setting. The ACR (DCA 2000) has the advantage of providing an immediate result.

Ultrasound-guided, intra-abdominal laser to treat acardiac pregnancies

A 19 year old woman in her first pregnancy at 18 weeks of gestation was referred to the fetal medicine unit because of an abnormal twin pregnancy in which it was believed that one of the fetuses had died. At ultrasound examination, there was one live fetus whose measurements were consistent with gestational age by her last menstrual period, with no obvious fetal abnormalities except a single umbilical artery. There were no signs of hydrops although the umbilical artery Doppler pulsatility index was elevated at 1.73, and there was a full bladder with a moderate increase in the amniotic fluid volume (amniotic fluid index 1⁄4 25.2 cm). No heart action was present in the other fetus, which was extremely hydropic and the lower body was more developed than the upper body. No face, neck or arms could be identified and the body consisted of a chest, abdomen and relatively well-developed legs, which showed movements. The diagnosis of an acardiac twin pregnancy was made. Perfusion at the cord insertion was demonstrated and using colour Doppler it was possible to identify that the blood was moving away from the acardiac twin via the umbilical vein and towards it in the umbilical arteries. The woman was told of the findings and the overall poor prognosis of this condition. She was given the options of either doing nothing with a high risk of preterm delivery, having laser coagulation of the acardiac fetal circulation or having a termination of pregnancy. She chose laser ablation, which was performed a week later. After infiltration of local anaesthetic into the maternal abdomen, a 17-gauge chorion villus sampling needle was passed into the abdomen of the acardiac twin under ultrasound guidance (Aspen, Acuson, Mountain View, California, USA) until its tip was in close proximity to the superior vesical arteries, as identified by colour Doppler. A laser fibre of 1.05 mm diameter (Surgical Laser Technologies, Philadelphia, Pennsylvania, USA) connected to a neodymium yttrium aluminium garnet laser (Surgical Laser Technologies, Philadelphia, Pennsylvania, USA) was then passed through the needle under ultrasound-guidance and the superior vesical arteries on both sides of the bladder were coagulated using pulses of 20 W to 30 W lasting three to five seconds until there was no visible flow on colour Doppler. The entire procedure lasted twenty minutes and the fetal heart rate of the other twin remained normal throughout the procedure. Subsequent serial scans showed normal growth, umbilical artery pulsatility index and amniotic fluid volume in the sac of the surviving fetus. In addition, no abnormalities of the brain were detected. Although the acardiac twin remained visible, it did not grow and no blood flow could be demonstrated within it at any time. Labour was induced at 38 weeks of gestation, and the woman had a vaginal delivery of a 3.52 kg well baby boy. Postnatal cranial ultrasound and magnetic resonance imaging of the brain of the baby were normal and at 18 months of age the child is developmentally normal. Postmortem examination of the acardiac twin, which was severely macerated, confirmed the ultrasound findings and in addition, the foot length was consistent with 17–18 weeks of gestation. It was not possible to identify the ablated superior vesical arteries during the internal examination or the site of insertion of the umbilical cord of the acardiac fetus into the placenta.

The effect of metabolic control on fetal nuchal translucency in women with insulin-dependent diabetes: a preliminary study

Diabetes could potentially alter fetal nuchal translucency (NT) measurements mainly by increasing microvascular permeability. The aim of this study was to test this hypothesis.

Optimal Interval between Middle Cerebral Artery Velocity Measurements when Monitoring Pregnancies Complicated by Red Cell Alloimmunization

Objective: To evaluate the optimal interval between middle cerebral artery (MCA) Doppler measurements when monitoring pregnancies complicated by red cell alloimmunization. Methods: Thirty-nine fetal blood samplings (FBS) performed on 24 pregnant women with red blood cell alloimmunization followed up using both MCA peak systolic velocity and time-averaged mean velocity measurements on weekly basis. Results: In total, 65.5 and 37.5% of women with moderate or severe fetal anemia had abnormal MCA Doppler values 1 and 2 weeks, respectively, before FBS was performed. Conclusions: A weekly assessment of women at risk for fetal anemia is optimal in most of the cases even though 35.5% of cases of moderate or severe fetal anemia are expected to have normal Doppler measurements the week before the decision of doing an FBS is made.

Normal growth and development following in utero diagnosis and treatment of homozygous α‐thalassaemia

a-Thalassaemia is a common genetic abnormality and its prevalence is highest in Southeast Asia, where it is estimated that 5– 15% of the population have a-globin gene deletions 1 . Consequently, homozygous a 0 -thalassaemia is the most common cause of non-immune hydrops accounting for between 53% and 81% of cases 2 . Due to an increase in migration of susceptible populations, a-thalassaemia mutations are more frequently encountered in the Western world. The first survivor in the UK of hydrops resulting from homozygous a 0 -thalassaemia treated with intrauterine transfusion is reported here.