Cordocentesis using the combined technique; needle guide-assisted and free-hand

Fetal heart rate response to cordocentesis and pregnancy outcome: A prospective cohort

OBJECTIVE

To evaluate fetal cardiac response to cordocentesis and whether such changes may affect pregnancy outcome.

METHODS

117 singleton pregnant women requiring percutaneous trans-abdominal cordocentesis were prospectively included. Fetal heart rate was continuously evaluated by ultrasound for 1 min after completion of cordocentesis and intermittently for 20 min more. Fetal and pregnancy outcomes were analyzed by grouping fetal cardiac response to cordocentesis into bradycardia, normal heart rate and tachycardia groups.

RESULTS

Women included in the study were 30.5+/-4.0 years old and had a gestational age of 23.7+/-2.0 weeks. Fetal blood sample obtained by cordocentesis was 3.1+/-0.8 ml. Fetal heart rate before cordocentesis was 149+/-8 beats per minute (bpm), ranging from 130 to 169 bpm. Fetal heart rate post-cordocentesis was 145+/-30 bpm (from 32 to 175 bpm). The incidence of bradycardia and tachycardia was 10.3% (n=12) and 6.0% (n=7), respectively. Fetal heart rate returned to normal levels in all cases at <or=5 minutes post-cordocentesis. In the tachycardia group, 6 cases had normal pregnancy outcome and one patient was lost to follow-up. In the bradycardia group, we observed two pregnancy terminations, one patient was lost to follow-up and nine were normal outcomes. In the group with normal heart rate (n=98), we observed one intrauterine fetal death, nine adverse fetal outcomes, eight pregnancy terminations and nine patients were lost to follow-up.

CONCLUSIONS

Transient fetal tachycardia and bradycardia were uncommon and were not associated with adverse fetal or pregnancy outcomes.

Fetal and neonatal alloimmune thrombocytopenia: progress and ongoing debates

Fetal and neonatal alloimmune thrombocytopenia (AIT) is a result of a parental incompatibility of platelet-specific antigens and the transplacental passage of maternal alloantibodies against the platelet antigen shared by the father and the fetus. It occurs in approximately 1 in 1000 live births and is the most common cause of severe thrombocytopenia in fetuses and term neonates. As screening programs are not routinely performed, most affected fetuses are identified after birth when neonatal thrombocytopenia is recognized. In severe cases, the affected fetus is identified as a result of suffering from an in utero intracranial hemorrhage. Once diagnosed, AIT must be treated antenatally as the disease can be more severe in subsequent pregnancies. While there have been many advances regarding the diagnosis and treatment of AIT, it is still difficult to predict the severity of disease and which therapy will be effective.

Ultrasound guidance for vascular access

The evidence that supports the general application of US guidance for venous access in the ED has reached a critical mass. The increasing familiarity of emergency physicians with US and the recent focus on patient safety and clinical outcomes has intensified attention on the capacity for US to improve patient care in the ED. US guidance can increase the safety and efficiency of venous access procedures and offers improved outcomes. The potential for these improvements is compelling, especially among certain types of ED patients such as those with difficult or complicated access. Varying levels of evidence support the use of US guidance over the traditional landmark approach for venous access in adult and pediatric populations and for central and peripheral veins. Many different techniques may be applied, depending on the clinical situation and equipment available.

A new guidance system for freehand, obstetric ultrasound-guided procedures

OBJECTIVE

To assess the performance of the UltraGuide 1000 system, and to compare ultrasound-guided freehand mid-trimester amniocentesis with and without the new guidance system.

METHODS

One hundred and sixty-nine women referred for mid-trimester genetic amniocentesis were divided into two groups: a control group of 99 women who underwent the procedure by the freehand technique with scored needles and 70 patients who had the procedure carried out with the aid of a guidance system (UltraGuide 1000) with non-scored needles. The procedures were compared for duration, number of punctures and repositionings of the needle, the visibility of the needle during the puncture and the number of bloody taps.

RESULTS

The study group had significantly lower rates of reinsertion (none vs. 7.1%), repositioning (7.1% vs. 17.7%), bloody taps (none vs. 6.1%), touching the fetus (5.7% vs. 22.2%) and prolonged duration of the procedure (4.3% vs. 14.4%) compared with the control group. There was one fetal loss in the control group. Non-visibility of the needle before reaching the amniotic sac occurred in 18.6% of cases in the study group and in 38.4% of cases in the control group.

CONCLUSIONS

The new guidance system combines the benefits of an attached guide with the flexibility of the 'freehand' technique. Use of the new guidance system for mid-trimester genetic amniocentesis increases needle visibility and lowers the incidence of common complications.

Fetal loss rate associated with cordocentesis at midgestation

OBJECTIVE

The aim of this study was to assess the risk of fetal loss attributable to cordocentesis at midgestation.

STUDY DESIGN

A cohort study was conducted during the period 1989-1999. Women undergoing cordocentesis between 16 and 24 weeks' gestation with singleton pregnancies without obvious fetal anomaly were recruited into the study group. The control subjects were selected prospectively on a one-to-one basis with strict matching for maternal age, parity, gestational age at recruitment, and socioeconomic status. Both groups were prospectively followed up until delivery.

RESULTS

A total of 1281 women with successful cordocentesis and their matched control subjects were recruited to the study. After exclusion of some pairs because of loss to follow-up or fetal malformations or severe disease necessitating termination of pregnancy, 1020 matched pairs were available to be compared with respect to fetal loss rate and pregnancy outcomes. The fetal loss rate was significantly higher among the study group (3.2% vs. 1.8%; P <.05, McNemar test). However, there were no significant differences in other obstetric complications between the study and control groups.

CONCLUSION

The incremental fetal loss rate associated with cordocentesis at midgestation was about 1.4%.