Intrauterine exchange transfusion of the fetus under ultrasound guidance: first successful report

The Application of Engineered Nanomaterials in Perinatal Therapeutics

Pregnancy is a vulnerable life stage for the mother and developing fetus. Because of this dual concern, approved therapeutic options for pre-existing conditions or pregnancy-induced pathologies, placental deformities, or fetal concerns are extremely limited. These cases often leave patients and clinicians having to choose between maternal health and fetal development. Recent advancements in nanomedicine and nanotherapeutic devices have made the development of perinatal therapeutics an attractive objective. However, perinatal medicine requires a multifaceted approach given the interactions between maternal, placental, and fetal physiology. Maternal-fetal interactions are centralized to the placenta, a specialized transient barrier organ, to allow for nutrient and waste exchange. Perinatal nanotherapeutics must be designed for placental avoidance or uptake. In this review, pregnancy-related conditions, experimental models, and modes of drug delivery during pregnancy are discussed.

Does an intrauterine exchange transfusion improve the fetal prognosis in parvovirus infection cases?

BACKGROUND

Almost 20% of parvovirus B19 foetal infections require intrauterine transfusions. In addition, myocardial dysfunction has been observed in severe parvovirus B19 infections. One objective of an intrauterine exchange transfusion (IUET) is to avoid an overload during the transfusion. Our aim was to study the obstetrical and neonatal outcomes in cases of IUETs performed for foetal parvovirus infections and to compare our survival rate to those studies in which simple in utero transfusions were chosen.

STUDY DESIGN AND METHODS

This was a retrospective monocentre study of all patients followed up for parvovirus B19 infections in which IUETs were performed. An IUET was indicated when foetal hydrops was observed and/or when severe foetal anaemia was diagnosed though an elevation in the middle cerebral artery peak systolic velocity. The characteristics of each pregnancy and the neonatal outcomes were studied until hospital discharge.

RESULTS

Thirty-five IUETs were performed in 26 foetuses. The median gestational age of the first IUET was 22.6 weeks. Only one foetal bradycardia incidence was recorded during the procedure. Three medical pregnancy terminations were observed in our series, secondary to severe cerebral anomalies confirmed in the magnetic resonance imaging. Five in utero deaths occurred, in which 2 of the foetuses underwent multiple IUETs. All the neonates had normal haemoglobin levels at birth, and none were transferred to the neonatal intensive care unit. The overall survival rate was 70%.

CONCLUSION

IUETs exhibit a survival rate similar to that of simple intrauterine transfusions in foetal parvovirus infection cases.

In utero treatment of severe fetal anemia resulting from fetomaternal red blood cell incompatibility: a comparison of simple transfusion and exchange transfusion

OBJECTIVE

To compare in utero exchange transfusions (IUET) and in utero simple transfusions (IUST) for the treatment of fetal anemia resulting from red blood cell fetomaternal incompatibility.

STUDY DESIGN

Retrospective comparative study from January 2006 through December 2011. The two techniques were compared for effectiveness, complications, and neonatal outcomes.

RESULTS

36 patients had 87 IUETs and 85 patients 241 IUSTs. Gestational age at the first transfusion was similar in both groups (IUET: 27±3.8 weeks; IUST: 27±4.7 weeks; NS) as was the initial fetal hemoglobin level (IUET: 6.4±2.8g/dL; IUST: 6.0±2.5g/dL; NS). No significant differences were noted for postprocedure complications or efficacy. The daily drop in hemoglobin level was similar in both groups (IUET: 0.41±0.23g/dL/day; IUST: 0.44±0.17g/dL/day; NS) as were the time intervals between two procedures. Gestational age at birth was earlier in the IUET group (34.4±1.3 weeks vs 35.5±1.8 weeks; p<0.001), but the postnatal transfusions or exchange transfusions rates and the duration of intensive phototherapy did not differ. No significant differences were noted for the overall survival rates (IUET: 100%; IUST: 96.4%; p>0.99).

CONCLUSION

IUET does not appear to provide any benefits compared with IUST, neither to be associated with a higher complication rate. The choice of the technique depends on availability of packed blood cells with high hematocrit (70-80%).

Umbilical cord haematoma as a complication of intrauterine intravascular blood transfusion

Between October 1985 and February 1989, 49 ultrasound-guided intravascular fetal blood transfusions were performed in 16 patients (14 with rhesus (Rh) isoimmunization, 2 with non-immunologic hydrops fetalis (NIHF)). As an intra-operative complication, perivascular haematoma of the cord occurred in three patients (7 per cent). In two cases, fetal bradycardia necessitated delivery by Caesarean section at 30 and 32 weeks' gestation, respectively. In the third case, fetal bradycardia developed during transfusion, at 31 weeks' gestation, but normalized within 3 min. The baby was delivered as planned at 36 weeks of gestation, after another transfusion at 34 weeks. Dislodgement of the needle tip into perivascular tissue, caused by sudden fetal or maternal movements, is the reason for this complication. The haematoma develops as a result of delayed recognition and continuous transfusion into Wharton's jelly. Cord haematoma may be diagnosed in time by continuous ultrasound imaging, as illustrated in case 3. To minimize the risk of needle dislodgement during transfusion, sedation of the mother and complete immobilization of the fetus by injecting a short-acting muscle relaxant into the umbilical vessel are recommended.

Intra-uterine exchange transfusion under ultrasound guidance

Thirty intra-uterine exchange transfusions (I.U.E.T.) under ultrasound guidance were performed on 15 pregnancies in 14 severely Rh-sensitized women. Our technique and a new method of catheterization of the umbilical cord are described. I.U.E.T. were commenced at 19-34 gestational weeks and repeated up to 5 times at 15 to 60 days intervals. The lowest pretransfusion fetal hemoglobin was 3 milligrams at 25 weeks. All the hydrops (4 cases) reversed a few days after the first procedure. The survival rate is 50% for hydropic fetuses and 66.6% for all cases. This technique avoids fetal hypervolemia and also too repetitive procedures by quick renewal of red cells. Catheterization offers a simple and safe access to the umbilical vein even with important fetal movements.