An audit of outcome in intravascular transfusions using the intrahepatic portion of the fetal umbilical vein compared to cordocentesis.

INTRODUCTION: Maternal red cell alloimmunization is a potential cause of perinatal morbidity and mortality. The outcome of severe disease has been transformed by the use of in-utero and particularly, fetal intravascular transfusion. In the majority of instances this is performed by cordocentesis. However, this cohort study represents the experience in a large tertiary referral centre in performing fetal intravascular transfusions via the intrahepatic vein (IHV). METHODS: Over an 8-year period, 1997-2004, 221 in-utero transfusions (IUT) were performed for rhesus disease in 66 pregnancies. 86% had severe fetal anaemia caused by anti-D, 10.6% by anti-Kell and 3.4% by anti-c. The median maternal age of the cohort was 31 years (range 19-43). The median gestation at initial IUT was 25 weeks (interquartile range (IQR) 23-29 weeks). RESULTS: A median number of three IUT were performed in each fetus (IQR 2-5) with a median haemoglobin at first fetal blood sampling of 7.3 g% (IQR 4.6-8.8 g%) (73% < or =5 SD and 27% < or =2 SD). Of the total intravascular transfusions, 170 were performed via the IHV (71.7%), 33 via cordocentesis (13.9%) and 1 by intracardiac puncture (0.5%). There were 'transient' bradycardias complicating 4.1% of all transfusions and amniorrhexis following 1.4%. 92% of babies were live born at a median gestation of 34 weeks (range 21-38) with a birth weight centile of 50 (range 3-90). There was no significant difference in intravascular transfusion complication rate when the procedure was performed via the IHV (7.6%) as compared to cord root puncture (3.0%) (Fisher's exact test, p < 0.47). CONCLUSION: IUT performed by fetal IHV puncture is safe and carries no excess morbidity when performed for severe rhesus disease.

Middle cerebral artery Doppler velocimetric assessment in two cases of hydrops fetalis without fetal anaemia.

OBJECTIVES: Raised middle cerebral artery (MCA) Doppler velocity has been shown to be highly predictive of moderate to severe fetal anaemia. We present two false-positive cases of raised MCA Doppler velocity in non-immune hydropic fetuses. METHODS: In both cases, routine investigations for fetal hydrops, as well as detailed ultrasound scanning and MCA peak-systolic velocity Doppler assessment (maximum velocity taken at zero degrees to the vessel), were performed. Fetal blood sampling was carried out at the same visit. RESULTS: MCA peak-systolic velocity values greater than 1.50 MoM for gestation were found in both cases. However, both fetuses had normal haemoglobin values and haematocrits. Both fetuses died in utero soon after diagnosis. CONCLUSIONS: A raised MCA velocity in a hydropic fetus may not always be due to fetal anaemia, rather it may indicate a fetus in poor condition perhaps due to cardiovascular decompensation and redistribution of blood to the fetal brain.

Prenatal bladder drainage in the management of fetal lower urinary tract obstruction: a systematic review and meta-analysis.

OBJECTIVE: To estimate the effect of prenatal bladder drainage on perinatal survival in fetuses with lower urinary tract obstruction. DATA SOURCES: Relevant articles were identified by searching the databases MEDLINE (1966-2002), EMBASE (1988-2002), and the Cochrane library (2000;4). METHODS OF STUDY SELECTION: Studies were selected if the effect of prenatal bladder drainage (vesicocentesis, vesicoamniotic shunt, or open fetal bladder surgery) on perinatal survival was reported in fetuses with ultrasonic evidence of lower urinary tract obstruction. Study selection, quality assessment, and data abstraction were performed independently and in duplicate. TABULATION, INTEGRATION, AND RESULTS: Sixteen observational studies that included nine case series (147 fetuses) and seven controlled series (195 fetuses) were identified. Study characteristics and quality were recorded for each study. Data on the effect of bladder drainage on perinatal survival were abstracted. Where controlled data were available, 2 x 2 tables were generated to compare the effects of bladder drainage versus no bladder drainage on perinatal survival. Pooled odds ratios (ORs) were used as summary measures of effect, and the results were stratified according to predicted fetal prognoses (based on ultrasound features and fetal urinary electrolytes). Among controlled studies, bladder drainage appeared to improve perinatal survival relative to no drainage (OR 2.5; 95% confidence interval [CI] 1.1, 5.9; P =.03). However, this observation was largely because among the subgroup of fetuses with a poor prognosis there was a marked improvement (OR 8.1; 95% CI 1.2, 52.9; P =.03). Improved perinatal outcome was also suggested in those fetuses considered to have a good prognosis (OR 2.8; 95% CI 0.7, 10.8; P =.13). CONCLUSION: There is a lack of high quality evidence to reliably inform clinical practice regarding prenatal bladder drainage in fetuses with ultrasonic evidence of lower urinary tract obstruction. The limited available evidence suggests that prenatal bladder drainage may improve perinatal survival in these fetuses, particularly those with poor predicted prognoses. Further research in the form of a multicenter randomized controlled trial is required to assess the short- and long-term effects of this intervention.

Twin pregnancy outcome and chorionicity.

BACKGROUND: Based on research of relatively poor quality, it is generally believed that dichorionic twins have lower perinatal mortality than monochorionic twins. We assessed the relationship between the pattern of perinatal loss in twin pregnancy and chorionicity. METHODS: A cohort study of 238 consecutive sets of twin pregnancies registered in our antenatal service over a 2-year period (1996-98) had chorionicity determined by ultrasound at 12-16 weeks' gestation. Follow up included scanning at 20 weeks' gestation for anomaly, and at 2-3-weekly intervals from 24 weeks' gestation onwards for growth and well being. Hazard ratios were computed for comparing the risk of death according to chorionicity. The perinatal loss patterns were analyzed according to gestational age at demize and that at delivery using survival analysis. RESULTS: Overall, 17/238 (7.1%) twin pregnancies suffered mortality: 14/190 (7.3%) amongst the dichorionic and 3/48 (6.2%) amongst the monochorionic twins. The hazard ratio for mortality was 0.89 (95% confidence interval 0.27-2.97, p = 0.85), considering gestational age at demize as the outcome. For gestational age at delivery as the outcome, the hazard ratio for mortality was 0.93 (95% confidence interval 0.27-3.15, p = 0.91). Survival analysis showed that amongst the dichorionic twins the hazard of death continued to rise throughout gestation. In contrast, the hazard of death for the monochorionic twins rose gradually to a maximum at 28 weeks' gestation and was then constant. CONCLUSION: Chorionicity did not affect the overall fetal loss rate amongst the twin pregnancies in our setting. There were differences in patterns of loss according to chorionicity, which require further investigation.