A simple set for intrauterine fetal blood transfusion constructed by readily available materials in every clinic.

Intrauterine fetal transfusion needs extensive experience and requires excellent eye-hand coordination, good equipment and experienced team workers to achieve success. While the needle is in the umbilical vein, an assistant withdraws and/or transfuses blood. The needle point should be kept still to prevent lacerations and dislodging. We propose a simple set for Intrauterine Fetal blood transfusion is constructed by readily available materials in every clinic to minimize needle tip movement and movements during syringe attachments and withdrawals during the intrauterine fetal transfusion. This makes possible to withdraw fetal blood sample, and to transfuse blood with minimal intervention.

Correlación entre el grado de anemia fetal intertransfusional y la medición doppler de la velocidad máxima del flujo en la arteria cerebral media en la anemia hemolítica por isoinmunización rh / Correlation between the degree of intertransfusional fetal anemia and peak flow velocity in the middle cerebral artery in fetuses with hemolytic anemia due to maternal red-cell alloinmunization

Objetivo: Evaluar la correlación entre la velocidad máxima sistólica de la arteria cerebral media y el grado de anemia, así como su potencial capacidad predictiva del grado de anemia fetal intertransfusional en tres pacientes con isoinmunización Rh.Material y métodos: Se describen tres casos de anemia fetal por isoinmunización Rh tratados con transfusión sanguínea intraútero. El seguimiento intertransfusional y la decisión de realizar una nueva cordocentesis se hizo según el protocolo clásico basado en la presencia de signos ecográficos de hidrops o la estimación del grado de hemólisis postransfusión. De forma paralela, se midió con eco-Doppler la velocidad máxima de la arteria cerebral media (VmáxACM) pre y postransfusión, así como entre las transfusiones.Resultados: Se realizaron un total de 11 cordocentesis con transfusión sanguínea. La medición de la VmáxACM se correlacionó con el grado de anemia, existiendo una correlación inversa entre ambos parámetros. La sensibilidad de la VmáxACM para detectar anemia moderada y grave fue del 100 por ciento. En nuestros casos la inclusión de la medición de la VmáxACM en los protocolos clínicos podría haber evitado tres cordocentesis.Conclusiones: Nuestros resultados preliminares sugieren la utilidad del estudio Doppler de la VmáxACM para el control del grado de anemia fetal entre transfusiones en los casos de anemia hemolítica por isoinmunización Rh. (AU)

Fetal outcome following intrauterine intravascular transfusion in rhesus alloimmunization.

The outcome of 14 pregnancies with severe rhesus alloimmunization was analyzed over a period of 16 months. Group A consisted of 7 cases who received ultrasound guided intravascular intrauterine packed red blood cell transfusions via the umbilical vein after determining fetal blood group and hematocrit. The outcome of these cases was compared with another 7 cases (Group B), who did not require intrauterine transfusions. The 7 cases in Group A received a total of 25 intrauterine transfusions between 25 to 33 weeks gestation. Procedure related complications encountered were transient fetal bradycardia on 4 occasions, difficulty in cord cannulation due to fetal movements in 2 cases and transient bleeding at puncture site in 2 cases. These complications were not associated with any maternal or fetal consequences. There was no procedure related mortality. Mean cord hemoglobin in Group A (12.52 g/dl) was significantly higher (p < 0.05) than in Group B (8.5 g/dl), and mean cord indirect serum bilirubin was significantly lower (p < 0.1) in Group A (2.5 mg/dl) than in Group B (5.8 mg/dl). Three neonates in Group A required one exchange transfusion each, as compared to all 7 in Group B who required a total of 12 exchange transfusions. All neonates in Group B survived, whereas 2 expired in Group A, one of severe intravascular coagulopathy and the other due to prematurity and hyaline membrane disease. Percutaneous ultrasound guided umbilical blood transfusions directly into the vascular system appears to be safe in experienced hands and has the potential to improve the prognosis of the severely alloimmunized fetus.

Needle modifications for invasive fetal procedures.

OBJECTIVE: To investigate the effect of needle size and siliconization on fetal blood sampling, transfusion, and electrocardiography. METHODS: Standard needles were modified by increasing the internal (but not the external) diameter and either siliconization of the bore or external Teflon coating. The siliconized needles were subjected to a series of flow experiments with either blood or saline at various driving pressures, and assessed in clinical use during fetal transfusion and fetal blood sampling. The Teflon-coated needles were used for fetal transfusion to try and facilitate the fetal electrocardiogram (ECG). RESULTS: Under conditions simulating fetal transfusion, the siliconized needle allowed a 93% increase in flow rate compared to the standard needle (P < .05). Samples obtained after fetal transfusion with the siliconized needles were free of clots, whereas 50% of the post-transfusion samples with the standard needle had clots present. Similarly, samples taken for fetal platelet count were free of platelet clumping and clots with siliconized needles, but not with standard needles. Fetal ECG recordings were recorded successfully when Teflon-coated needles were used to access the fetal circulation via the intrahepatic vein. CONCLUSIONS: Modifications to standard needles improved blood flow and reduced the activation of coagulation during both fetal intravascular transfusion and platelet count measurement. Direct fetal ECG recording was facilitated by Teflon coating the external surface of the needle, insulating the fetal signal from maternal electrical signals.

[Preparation of maternal platelets collected by separator for use in fetal transfusion in a case of alloimmunization by anti-PLA1]. / Préparation de plaquettes maternelles collectées sur séparateur de cellules en vue d'une transfusion foetale dans un cas d'allo-immunisation par anti-PLA1.

In one case of fetal thrombocytopenia due to maternal immunization against PLA1 fetal platelet antigen, maternal platelets were collected by automated plasmapheresis. The platelets were collected 24 hours before fetal transfusion at 28, 29, 31 and 36 weeks of gestation. The maternal platelets were irradiated and concentrated in a small volume (7.10(10) to 1,4.10(11) plts in less than 20 ml maternal plasma) a few hours before transfusion. When prepared as described, maximal and irreversible platelet aggregation is obtained with 20 microM of ADP and the pH is over 6, 5-6 hours after concentration. The amounts of transfused platelets were determined to increase theoretically fetal platelet counts over 200,000 plts/mm3. The fetal platelet counts, determined immediately after transfusion, showed an increase of 100,000 plts/mm3. Prenatal fetal transfusion of maternal platelets is available to avoid fetal bleeding during delivery, and during the early neonatal period.

Prevention of Rh isoimmunization and treatment of the compromised fetus.

Intrauterine intravascular transfusion for the treatment of severe erythroblastosis fetalis has resulted in a number of benefits: (a) Direct access to the fetal vasculature allows an accurate assessment and prompt correction of anemia, albeit temporary. In contrast, intraperitoneally transfused blood may be absorbed erratically, especially in the face of ascites. (b) Intravascular treatments can be performed, in general, as early as 17 weeks of gestation, earlier than intraperitoneal approaches permit. (c) Reversal of hydrops along with the correction of anemia and hypoproteinemia has significantly reduced neonatal morbidity and mortality. None of the surviving neonates in our series required either thoracentesis or paracentesis following delivery, and 40% did not require neonatal exchange transfusion. (d) Treatments may be safely performed until pulmonic maturity has been established and/or an EFW of greater than 2,000 g has been reached, reducing problems of prematurity. (e) Central vein and umbilical vein hypertension may be arrested or prevented, thereby allowing fetal liver function to return to normal. While isoimmunization stands as a disease that has been quite successfully reduced in frequency and severity by the careful attention and treatment by obstetricians, cases still occur. Due to the reduced frequency of severe disease, fewer physicians are trained and experienced in performing this difficult procedure. As fewer transfusions are required, the value of regionalized treatment centers will have to be considered carefully, in order to maximize the experience and efficiency of the intravascular intrauterine transfusion treatment teams.

Percutaneous umbilical blood sampling.

Percutaneous umbilical blood sampling (PUBS) provides a new and exciting method for assessment and management of certain fetal disorders. This procedure offers direct access to the fetal circulation for obtaining blood samples or for transfusing the fetus in utero. Although investigational, PUBS offers treatment approaches that were not previously available. This ability to treat the fetus in utero can prolong pregnancy, resulting in decreased prematurity and mortality rates for infants with erythroblastosis fetalis. This article describes the PUBS procedure and the indications for PUBS and discusses the nursing implications associated with the care of women undergoing PUBS.

Intravascular intrauterine transfusion for severe erythroblastosis fetalis using different techniques.

Over a 3-year period, 44 ultrasound-guided intravascular transfusions were performed between 18 and 32 weeks on 15 patients with severe erythroblastosis fetalis due to Rh immunization. In 4 fetuses, the first transfusion was performed before 20 weeks, in 6 between 20 and 25 weeks and in the remaining 5 between 25 and 31 weeks. Eight of the 15 fetuses were hydropic at the time of referral. Five transfusions were done in the intrahepatic umbilical vein, 6 were simple transfusions via percutaneous umbilical cord puncture, and 33 were partial exchange. There were 4 intrauterine deaths before 26 weeks, despite successfully performed transfusions: 3 of these fetuses were severely hydropic, while in the remaining fetus hydrops had been reversed in utero. Following delivery by cesarean section at 32 weeks of gestation, 1 of the neonates developed respiratory distress syndrome and died 17 h after birth. The overall survival rate was 67% (10 of 15 cases): 4 of the 8 hydropic fetuses (50%) and 6 of the 7 nonhydropic fetuses (83%) were alive at birth and survived the perinatal period. Three of the 5 losses occurred among the first 4 cases, while in the last 11 cases the survival rate increased to 82% (9 of 11).

Use of a small-gauge needle for intrauterine fetal transfusions.

Intraperitoneal intrauterine fetal transfusions have generally been performed with large-gauge Tuohy needles, which increase the risk of traumatic fetal complications. We feel that this technique can be improved by use of a small-gauge needle and continuous ultrasound visualization. A series of 20 transfusions is presented.

Intrauterine fetal transfusions: Winnipeg 1982.

Perinatal survival after fetal transfusion in Winnipeg from February 1978 to June 1980 (52%-11 of 21 transfused) was worse than in the preceding 12-year period (70%-79 of 113 transfused). The cause was determined to be narrowing of the epidural transfusion catheter side hole opening diameters, which caused donor red cell hemolysis and hydrops fetalis. Catheter-induced red cell hemolysis was directly responsible for three perinatal deaths in this interval and probably contributed to two others. Catheter-induced red cell hemolysis was prevented completely by removal of the catheter tip and side hole openings, allowing donor red fell egress through the open end of the catheter. Following the institution of real-time ultrasound scan surveillance during and after intrauterine transfusion, survival for the interval from July 1980 to June 1982 was 92% (22 of 24 transfused), by far the series' best intrauterine transfusion survival rate. Hydropic fetal survival rate in the same period was 75% (six of eight transfused). With meticulous prenatal care, amniotic fluid delta OD450 measurements beginning at 20.5 weeks' gestation, and intrauterine transfusion carried out under ultrasound guidance, beginning as early as 22.5 weeks' gestation if necessary, the Rh Laboratory has achieved extremely satisfactory perinatal salvage following intrauterine transfusion. Intensive plasma exchange, as an adjunct to the above measures, should be reserved for the pregnant woman with a history of hydropic fetal death before 28 weeks' gestation.