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PubMed1995

[Preventive anti-D after massive fetomaternal hemorrhage].

In the 36th week of gestation intrauterine death of both twins occurred in a 31-year old primigravida. The examination of the C- and the D-antigen of the mother's blood (result of previous testing: AB Rhesus negative) immediately before delivery showed a mixed field agglutination which pointed to a fetomaternal macrotransfusion. Fetal haemoglobin in the mother's circulation was 7.8% of her total haemoglobin, so that a fetomaternal haemorrhage of about 440 ml whole blood had to be suspected. For Rhesus-prophylaxis 17 standard doses of anti-D-immunoglobulin were administered intramuscularly distributed over 4 days. No adverse effects were seen; fetal haemoglobin dropped to 2.0% 5 days and to 0.1% 15 days after the beginning of the treatment. A control examination after 9 months showed no signs of a Rhesus-(D)-sensitisation of the patient.

Female↗
PubMed1991

[Fetomaternal transfusions in complicated and uncomplicated pregnancy].

Fetomaternal bleeding in pregnancy is the most common cause of rhesus immunization. In this study we evaluated the amount of fetomaternal bleeding during pregnancies with and without complications. The data from 1204 patients are analyzed. Fetomaternal bleeding was of clinical relevance (HbF greater than 0.01%) in 6% of all uncomplicated pregnancies. There was no increased fetomaternal bleeding in pregnancies complicated by gestosis, preliminary labour, placenta praevia, trauma, and diabetes in pregnancy. In cases with premature rupture of the amnion or vaginal bleeding in pregnancy we observed an increased percentage of fetomaternal bleeding into the mother's circulation. Nearly 25% of all patients with hydrops fetalis had clinical relevant fetomaternal bleeding (HbF greater than 0.01%).

Adolescent↗
PubMed1996

Advantages of larger volume, less frequent intrauterine red blood cell transfusions for maternal red cell alloimmunization.

Larger volume intravascular transfusions to manage severe maternal red cell alloimmunization in pregnancy may prolong the interval between procedures without increasing maternal, fetal, or neonatal complications. A retrospective cohort study compared the management and outcome of 19 patients with severe red cell alloimmunization managed at two facilities with different intravascular transfusion protocols. The volume of blood transfused, pre- and post-transfusion fetal hematocrit, and interval (days) between intravascular transfusions were compared. The respective maternal, fetal, and neonatal results were compared. The red blood cell volume transfused per procedure and the post- but not pre-transfusion fetal hematocrits were higher at New York Hospital than at Westchester County Medical Center. The interval between transfusions at New York Hospital (25.2 +/- 8.65 days) was longer than at Westchester County Medical Center (13.5 +/- 6.0 days, p < 0.0001). Although larger volume transfusion was occasionally associated with transient fetal bradycardia, all red blood cell transfusions were completed without complication. The adverse outcomes, complication rates, and neonatal outcomes were otherwise similar in both management protocols. It is possible to significantly increase the interval between intravascular transfusions with larger transfusion volumes for the management of severe maternal red cell alloimmunization without undue risk. The overall risk for the fetus and mother may be reduced by performing fewer transfusions and avoiding additional blood product exposures.

Blood Transfusion, Intrauterine↗
PubMed1994

Oxygenation of the human fetus as a function of hemoglobulin concentration.

We studied the relationships between fetal hemoglobin concentration, acid base status, and lactate concentration in umbilical venous and fetal heart blood in 157 fetuses affected by blood group incompatibility who had been exposed for 214 fetal blood sampling procedures (cordocentesis in 153 and intracardiac puncture in 61 cases). All blood samplings were obtained before fetal blood transfusions were administered. The results indicate that the human fetus can maintain a normal acid-base status until a 50% reduction of the hemoglobin concentration. A further reduction of hemoglobulin is associated with an accumulation of lactate both in umbilical venous and fetal heart blood. The partial oxygen tension and the oxygen saturation in umbilical venous blood remained virtually unchanged with decreasing hemoglobin concentration (r = -0.11, P = 0.21; r = 0.09, P = 0.31, respectively), whereas these parameters decreased significantly (r = 0.33, P = 0.02; r = 34, P = 0.02) in blood obtained from the fetal heart. The partial carbon dioxide tension of umbilical vein blood decreases significantly with a reduced hemoglobin concentration (r = 0.25 P = 0.008). We speculate that these alterations in acid-base status in umbilical vein and fetal heart blood reflect a circulatory transition from a high to a low cardiac output as the hemoglobin concentration decreases.

Acid-Base Equilibrium↗
PubMed1987

Hydrops fetalis associated with immunologic and nonimmunologic factors.

Described is a pregnancy complicated by severe Rh sensitization and hydrops fetalis which was managed aggressively with frequent intrauterine transfusions initiated at 21 1/2 weeks of gestation. No improvement or only temporary improvement of the fetal hydrops was observed after each intrauterine transfusion. Postmortem examination of the infant revealed the additional presence of nonimmunologic factors involved such as pulmonic atresia and lung hypoplasia. In cases of severe Rh sensitization associated with persistent fetal hydrops despite frequent intrauterine transfusions, the presence of coexistent factors for nonimmunologic fetal hydrops should be considered.

Adult↗
PubMed1987

[Histometric studies of placental villi in Rh incompatibility].

The delay in maturation of placental terminal villi in cases of Rh-incompatibility has often been described. The terminal villi of sixteen placentas from pregnancies complicated by Rh-incompatibility histometric were studied. Twenty-two placentas of healthy mothers who had born healthy babies after normal pregnancies served as a control group. The severity of the Rh-incompatibility was classified according to the clinical histories of the newborns and the criteria of Liley. The average area of a cross-section of a terminal villus was 3402 microns 2 (control group 2150 micronsoff; the degree of vascularization was calculated to be 6.5% (control group 30.5%). The other villous parameters measured or calculated show that maturation of the placenta is extremely retarded in cases of Rh-incompatibility. This failure in differentiation can not be compensated for by an enlargement of the organ as a whole. It was shown that the changes in the placental villi are closely correlated to the severity of the fetal disease.

Birth Weight↗
PubMed1987

[Histometric case report of a placenta following intra-uterine therapy of rhesus incompatibility].

In Rh-incompatibility the human placenta shows a prominent retardation of maturation. The placental insufficiency caused by these changes, combined with the existing hemolysis, represents an additional danger to the fetus. In a patient with severe Rh-incompatibility several Rh-negative blood transfusions were performed between the 26th and 30th weeks of gestation via sonographically guided puncture of the umbilical vein. Morphometric studies of the placenta were performed and the results compared with data already obtained from normal mature placentas and placentas from pregnancies complicated by Rh-incompatibility. Small terminal villi with a surface area identical to normal mature placentas were found. There was no improvement in vascularization when compared with other placentas from Rh-incompatible pregnancies. Nevertheless, isolated rebuilding of epithelial plates was found. The authors interpret these morphological phenomena as a "partial postmaturation" of the placenta as regards the development of the terminal villi. The absence of reproliferation of the villous vessels as well as the lack of any extensive regeneration of the epithelial plates could be due to the short time which elapsed between transfusion therapy and the inevitable indication for caesarean section. Intensive intrauterine therapy reduces the risk to the fetus due to immunologic complications, as well that due to placental insufficiency, as evidenced by the additional differentiation of villi.

Adolescent↗
PubMedDate not supplied

[High dosage immunoglobulin therapy in Rhesus incompatibility].

From September 1992 to the end of August 1993 we treated fourteen children who suffered from rhesus hemolytic disease with high-dose intravenous immune globulin G. Eleven patients did not require an exchange transfusion, three needed an exchange transfusion despite immune globulin therapy. Although an exchange transfusion cannot be avoided in all patients, this new method is an important addition to the currently available possibilities of treatment. It is without adverse side effects and helps to lower the number of exchange transfusions.

Bilirubin↗
PubMed2000

Noninvasive diagnosis by Doppler ultrasonography of fetal anemia due to maternal red-cell alloimmunization. Collaborative Group for Doppler Assessment of the Blood Velocity in Anemic Fetuses.

BACKGROUND: Invasive techniques such as amniocentesis and cordocentesis are used for diagnosis and treatment in fetuses at risk for anemia due to maternal red-cell alloimmunization. The purpose of our study was to determine the value of noninvasive measurements of the velocity of blood flow in the fetal middle cerebral artery for the diagnosis of fetal anemia. METHODS: We measured the hemoglobin concentration in blood obtained by cordocentesis and also the peak velocity of systolic blood flow in the middle cerebral artery in 111 fetuses at risk for anemia due to maternal red-cell alloimmunization. Peak systolic velocity was measured by Doppler velocimetry. To identify the fetuses with anemia, the hemoglobin values of those at risk were compared with the values in 265 normal fetuses. RESULTS: Fetal hemoglobin concentrations increased with increasing gestational age in the 265 normal fetuses. Among the 111 fetuses at risk for anemia, 41 fetuses did not have anemia; 35 had mild anemia; 4 had moderate anemia; and 31, including 12 with hydrops, had severe anemia. The sensitivity of an increased peak velocity of systolic blood flow in the middle cerebral artery for the prediction of moderate or severe anemia was 100 percent either in the presence or in the absence of hydrops (95 percent confidence interval, 86 to 100 percent for the 23 fetuses without hydrops), with a false positive rate of 12 percent. CONCLUSIONS: In fetuses without hydrops that are at risk because of maternal red-cell alloimmunization, moderate and severe anemia can be detected noninvasively by Doppler ultrasonography on the basis of an increase in the peak velocity of systolic blood flow in the middle cerebral artery.

Blood Flow Velocity↗
PubMed2006

Doppler ultrasonography versus amniocentesis to predict fetal anemia.

BACKGROUND: Pregnancies complicated by Rh alloimmunization have been evaluated with the use of serial invasive amniocentesis to determine bilirubin levels by measuring in the amniotic fluid the change in optical density at a wavelength of 450 nm (DeltaOD450); however, this procedure carries risks. Noninvasive Doppler ultrasonographic measurement of the peak velocity of systolic blood flow in the middle cerebral artery also predicts severe fetal anemia, but this test has not been rigorously evaluated in comparison with amniotic-fluid DeltaOD450. METHODS: We performed a prospective, international, multicenter study including women with RhD-, Rhc-, RhE-, or Fy(a)-alloimmunized pregnancies with indirect antiglobulin titers of at least 1:64 and antigen-positive fetuses to assess whether Doppler ultrasonographic measurement of the peak systolic velocity of blood flow in the middle cerebral artery was at least as sensitive and accurate as measurement of amniotic-fluid DeltaOD450 for diagnosing severe fetal anemia. The results of the two tests were compared with the incidence of fetal anemia, as determined by measurement of hemoglobin levels in fetal blood. RESULTS: Of 165 fetuses, 74 had severe anemia. For the detection of severe fetal anemia, Doppler ultrasonography of the middle cerebral artery had a sensitivity of 88 percent (95 percent confidence interval, 78 to 93 percent), a specificity of 82 percent (95 percent confidence interval, 73 to 89 percent), and an accuracy of 85 percent (95 percent confidence interval, 79 to 90 percent). Amniotic-fluid DeltaOD450 had a sensitivity of 76 percent (95 percent confidence interval, 65 to 84 percent), a specificity of 77 percent (95 percent confidence interval, 67 to 84 percent), and an accuracy of 76 percent (95 percent confidence interval, 69 to 82 percent). Doppler ultrasonography was more sensitive, by 12 percentage points (95 percent confidence interval, 0.3 to 24.0), and more accurate, by 9 percentage points (95 percent confidence interval, 1.1 to 15.9), than measurement of amniotic-fluid DeltaOD450. CONCLUSIONS: Doppler measurement of the peak velocity of systolic blood flow in the middle cerebral artery can safely replace invasive testing in the management of Rh-alloimmunized pregnancies. (ClinicalTrials.gov number, NCT00295516.).

Amniocentesis↗
PubMed2000

Middle cerebral artery Doppler velocimetric deceleration angle as a predictor of fetal anemia in Rh-alloimmunized fetuses without hydrops.

OBJECTIVE: The purpose of this study was to evaluate the screening performance of a new middle cerebral artery Doppler velocimetric index for the prediction of fetal anemia. STUDY DESIGN: Doppler velocimetry of the middle cerebral artery was performed before cordocentesis in 24 Rh-alloimmunized fetuses without hydrops on 52 occasions. The angle between the line describing the average slope during the diastolic phase of the cardiac cycle and the vertical, the middle cerebral artery standardized deceleration angle, was measured. The deceleration angle values were expressed in multiples of the median for gestational age. The screening performances of deceleration angle for the prediction of anemia (difference between expected mean hemoglobin level and measured value >/=2 g/dL) and severe anemia (hemoglobin deficit >/=5 g/dL) were determined. RESULTS: The mean (+/-SD) gestational age at cordocentesis was 28.6 +/- 5.7 weeks' gestation. The risk of fetal anemia increased with decreasing deceleration angle values. The sensitivity and false-positive rate for the detection of anemia in cases with no previous transfusions (one measurement per patient) were 72.0% and 13.3%, respectively; among those with one previous transfusion the values were 90.0% and 0.0%, respectively. For severe anemia the corresponding values were 100% and 0%, respectively, among those with no previous transfusions and 100.0% and 16.7%, respectively, among those with one previous transfusion. There was no risk of severe anemia when the angle was >0.9 multiples of the median. The risk of anemia was significantly reduced with an angle greater than the median for gestational age (deceleration angle >1.0 multiples of the median; relative risk, 0.09; 95% confidence interval, 0.02-0.37). The risk was significantly increased with an angle less than the median for gestational age (deceleration angle <1.0 multiples of the median; relative risk, 30.0; 95% confidence interval, 5.9-158.4). CONCLUSION: The risk of fetal hydrops is remote in the absence of severe anemia. With a new Doppler velocimetric index in the middle cerebral artery the risk of severe anemia was found to be low when the deceleration angle was >0.9 multiples of the median. Anemia can also be predicted with this index. The high sensitivities and acceptable false-positive rates support the potential clinical applicability of the method to reduce the reliance on cordocentesis in Rh alloimmunization. Our findings appear to validate the utility of the deceleration angle for the prediction of fetal anemia.

Anemia↗
PubMed2001

Ultrasonographic surveillance in red blood cell alloimmunization.

OBJECTIVE: This study was undertaken to audit ultrasonographic measurements of fetal liver length and middle cerebral artery peak velocity in cases of red blood cell alloimmunization between 1986 and 1999. STUDY DESIGN: A total of 200 fetuses at risk for anemia because of red blood cell alloimmunization underwent ultrasonographic measurement of the length of the right lobe of the liver, 45 underwent Doppler recording of middle cerebral artery peak velocity, and 119 underwent fetal blood sampling. RESULTS: The overall survival was 188 of 200 (94%). Among 69 fetuses found to have anemia, liver length values in 64 (93%) were at the 95th percentile or greater, and the other 5 were in the upper part of the normal range. The middle cerebral artery peak velocity was > or =95th percentile in 15 of the 19 cases of anemia in which this value was measured (79%). Among those measured within 1 week of birth, all liver lengths were at least in the upper part of the normal range, with most >95th percentile, including 1 case with a cord blood hemoglobin concentration <90 g/L. CONCLUSIONS: All fetuses with anemia identified at fetal blood sampling had enlarged livers with 93% at > or =95th percentile. The peak velocity in the middle cerebral artery was abnormal in most fetuses with anemia.

Blood Flow Velocity↗