Biomedical subjects

A A Baschat

Publications and source records attributed to A A Baschat.

At least 37 records · Page 2Linked to original sources

PubMed2003

Prevalence of viral DNA in amniotic fluid of low-risk pregnancies in the second trimester.

AIM: The association between fetal viral infection and adverse pregnancy outcome is well documented. However, the prevalence of common viral pathogens in the amniotic fluid of normal pregnancies is not established. The purpose of this study was to determine this prevalence in asymptomatic patients. METHODS: This was a prospective observational study of patients at low risk for viral infection who were referred for second-trimester genetic amniocentesis. In patients with normal fetal anatomy on ultrasound and a normal fetal karyotype, a 2-ml aliquot of amniotic fluid obtained at amniocentesis was analyzed by multiplex polymerase chain reaction for cytomegalovirus (CMV), parvovirus B19, adenovirus, enterovirus, herpes simplex virus (HSV), respiratory syncytial virus (RSV) and Epstein-Barr virus (EBV). RESULTS: Among 686 patients, advanced maternal age was the most common indication for genetic testing (n = 469, 68.4%), followed by elevated aneuploidy risk on triple screen (n = 164, 23.9%), elevated maternal serum alpha-fetoprotein (n = 20, 2.9%), previous aneuploidy (n = 16, 2.3%) and family history of inheritable disease (n = 14, 2.1%). Forty-four (6.4%) amniotic fluid samples were positive for viral genome. A single genome was amplified in 41 samples (93%). In three samples, two viral genomes were identified. Adenovirus was most frequently identified (37/44), followed by CMV (5/44), EBV (2/44), enterovirus (2/44) and RSV (1/44). Parvovirus and HSV were not identified. There was a bimodal seasonal variation in prevalence, with the highest prevalence during the summer and late winter. CONCLUSION: Viral genome is commonly found in amniotic fluid with a sonographically normal fetus, and the prevalence follows a seasonal pattern. The mechanism, significance and effects of this asymptomatic viral presence require further study.

Adenoviridae↗

PubMed2002

Prenatal sonographic features of Harlequin ichthyosis.

Harlequin ichthyosis (HI) is a severe and usually fatal congenital keratinization disorder with autosomal recessive inheritance. For over a decade, prenatal diagnosis of HI relied on fetoscopic or sonographically guided skin biopsies, and, therefore, was limited to previously affected families. Only a few cases of prenatal sonographic diagnosis have been published and the sonographic findings are variable. We report a case of HI, in which the typical features were detected during fetal life but the condition remained undiagnosed at 35 weeks' gestational age in this pregnancy complicated by premature rupture of membranes, oligohydramnios and intrauterine growth retardation. The documented prenatal findings were a flat profile with absent nose; a large mouth, widely gaping open; dysplastic ears; abnormal fixed position of the hands; and edema of thighs and feet; and intrauterine growth retardation. Following elective cesarean section the infant died of septicemia 12 days post-partum despite etretinate and antibiotic treatment. The sonographic features of HI are discussed together with those previously reported and an attempt is made to delineate sonographic markers of this rare disorder.

Adult↗

PubMed2002

Flecainide in the intrauterine treatment of fetal supraventricular tachycardia.

OBJECTIVES: To assess the efficacy of flecainide in the intrauterine treatment of fetal supraventricular tachycardia (SVT) with 1 : 1 atrioventricular conduction. DESIGN: Twenty fetuses (21-35 weeks of gestation) with SVT ranging between 215 and 280 bpm were analyzed retrospectively. Fetuses received flecainide and digoxin as either first, second or third line therapy. Intracardiac blood flow, venous Doppler waveforms and cardiotocograms were evaluated before and after drug induced conversion to sinus rhythm. RESULTS: After initiation of combined flecainide and digoxin therapy, the median time interval until final conversion to sinus rhythm was 5 days (range, 0-14 days). The majority of fetuses (n = 15; 75%) converted to sinus rhythm within 7 days of treatment, whereas the remaining five (25%) showed initial reduction of the heart rate to 160-215 bpm over several days, with restoration of a triphasic venous blood flow pattern before late conversion within 7-14 days after initiation of flecainide treatment. One of these fetuses showed a decrease in fetal heart rate to 160-190 bpm without conversion to sinus rhythm but with resolution of hydrops. All fetuses survived. CONCLUSIONS: Flecainide is safe and highly effective in the intrauterine treatment of hydropic fetuses with supraventricular tachycardia. Conversion into sinus rhythm can be expected 72 h after initiation of therapy but may take up to 14 days. Therefore therapy should be continued beyond 72 h, especially when an initial decrease of fetal heart rate is observed which may represent an early therapeutic response.

Anti-Arrhythmia Agents↗

PubMed2002

First-trimester diagnosis of fetal hepatic cyst.

Fetal intra-abdominal cysts seen on antenatal sonography pose a diagnostic problem as they may have many etiological origins. We present a case of a hepatic cyst measuring 11 x 7 x 7 mm that was diagnosed at 13 weeks' gestation by transvaginal sonography. The cyst increased in proportion with the growth of the fetus. Ultrasound-guided needle aspiration of the cyst at 22 weeks' gestation helped to clearly identify the formerly displaced gall bladder and demonstrated the intrahepatic location of the cyst. The aspirated fluid was identified as bile. After aspiration the fluid reaccumulated rapidly. Shortly prior to delivery the cyst measured 75 x 44 x 46 mm. At 39 weeks of gestation a female infant was delivered by forceps (3610 g; Apgar 9/10/10 at 1, 5 and 10 min, respectively). Increasing cyst size and concomitant feeding problems prompted surgery on the 14th day postpartum. A large hepatic cyst was partially excised and marsupialized, confirming the prenatal diagnosis. The postoperative course was complicated by cholangitis, septicemia and recurrence of the cyst. Therefore Roux-en-Y hepatojejunostomy was performed in the second month of life. The postoperative period was uneventful and the child was doing well at the time of writing.

Adult↗

PubMed2002

Antenatal prediction of intraventricular hemorrhage in fetal growth restriction: what is the role of Doppler?

OBJECTIVE: To evaluate relationships between neonatal intraventricular hemorrhage and altered brain blood flow in preterm growth-restricted fetuses. METHODS: One hundred and thirteen growth-restricted fetuses (birth weight < 10th centile and umbilical artery pulsatility index > two standard deviations above gestational age mean) which delivered prematurely (< 34.0 weeks) were studied. Three expressions of altered brain blood flow were defined: 'brain sparing'= middle cerebral artery pulsatility index > two standard deviations below the gestational age mean, 'centralization' = ratio of middle cerebral artery/umbilical artery pulsatility indices (cerebroplacental ratio) > two standard deviations below the gestational age mean, and 'redistribution' = absent or reversed umbilical artery end-diastolic velocity. Intraventricular hemorrhage was graded after Papile (I-IV) by cranial ultrasound performed within 7 days of delivery. RESULTS: Sixty-seven (59.3%) fetuses had brain sparing, 84 (74.3%) had centralization and 51 (45.1%) had redistribution. Fifteen (13.3%) neonates had intraventricular hemorrhage and were more likely to have a biophysical profile < 6, earlier delivery for fetal indications, lower cord artery pH, HCO3, hemoglobin, and platelets, a 10-min Apgar score < 7 and high perinatal mortality (5/15; 33.3%). No associations between intraventricular hemorrhage and brain sparing or centralization were identified. However, neonates with intraventricular hemorrhage had significantly higher umbilical artery pulsatility index deviations from the gestational age mean and a relative risk of 4.9-fold for intraventricular hemorrhage with redistribution (95% confidence interval, 1.5-16.3; P < 0.005). Multiple logistic regression revealed significant associations between intraventricular hemorrhage and a low 10-min Apgar score (r = 0.30, P < 0.005) and low hemoglobin (r = 0.28), gestational age at delivery (r = 0.25) and birth-weight centiles (r = 0.23) (P < 0.05). No Doppler parameter was identified as an independent contributor to intraventricular hemorrhage. CONCLUSION: While loss of umbilical artery end-diastolic velocity early in gestation significantly increases the risk for neonatal intraventricular hemorrhage, prematurity and difficult transition to extrauterine life remain the most important determinants of intraventricular hemorrhage.

Apgar Score↗

PubMed2002

Prenatal diagnosis and management of fetuses with liver hemangiomata.

OBJECTIVES: To study the relationship between prenatal appearance and perinatal outcome of fetuses with hepatic hemangiomata with special emphasis on criteria that may help to improve perinatal management. METHODS: In a tertiary referral center six fetuses with hepatic hemangiomata were evaluated by gray-scale, color, and pulsed wave Doppler ultrasound between 1994 and 2000. Fetal blood sampling was performed in four cases. All data (computerized files and video tapes) were analyzed retrospectively. RESULTS: Two fetuses showed very similar sonographic findings. They had an isolated large ('giant') round hepatic hemangioma (diameter 43 and 68 mm, respectively) supplied by one hepatic artery and drained by one hepatic vein, both of them showing high velocity and low pulsatility blood flow. Fetal blood count and coagulation parameters were normal in one case, whereas the other fetus showed a Kasabach-Merritt sequence with severe thrombocytopenia (10 platelets/nL) and mild disseminated intravascular coagulation. Intrauterine platelet transfusion was performed immediately prior to planned Cesarean delivery. Rapid platelet consumption continued postnatally, requiring several thrombocyte transfusions. Platelet counts stabilized only after tumor resection on the second day of life. One fetus with diffuse neonatal hemangiomatosis developed high-output cardiac failure with hydrops in addition to Kasabach-Merritt sequence (15 platelets/nL), and died following premature delivery. Three fetuses, however, showing an isolated small hyperechogenic hepatic hemangioma (5, 5, and 6 mm in diameter, respectively) did not develop any perinatal complications. CONCLUSION: Large fetal liver hemangiomata and diffuse hemangiomatosis may cause severe perinatal complications, particularly high-output cardiac failure and/or Kasabach-Merritt sequence with severe consumption of platelets and clotting factors and hemolytic anemia. Fetal blood sampling enables the prenatal detection of these potential complications, allowing critical modification of perinatal management such as intrauterine platelet transfusion, especially directly before delivery. In contrast, isolated small hyperreflexic hepatic hemangiomata do not appear to be associated with any of these fetal and postnatal sequelae.

Adult↗

PubMed2002

Two-dimensional and M-mode echocardiography of the fetal coronary sinus.

OBJECTIVE: To document fetal coronary sinus dimensions in normal pregnancy. METHODS: Two hundred and sixty-five normal fetuses in which congenital cardiac defects had been excluded were examined cross-sectionally between 21 and 38 weeks of gestation. From the apical or basal four-chamber view the transducer was tilted towards the inferior cardiac surface in order to visualize the coronary sinus by real-time ultrasound. Maximum systolic and diastolic diameters were measured using M-mode. Reference ranges were constructed and the ratio of systolic and diastolic diameters calculated. Data from two fetuses, one with supraventricular tachycardia and a second one with hydrops secondary to anemia, were also compared. RESULTS: Visualization and measurement of the coronary sinus were successful in 258 (97.4%) patients. The coronary sinus systolic and diastolic diameters increased significantly with gestational age (maximum systolic diameter, 1.6 mm at 21 weeks to 4 mm at 38 weeks; maximum diastolic diameter, 0.9 mm at 20 weeks to 2.2 mm at 38 weeks). The ratio of systolic to diastolic diameters remained relatively constant (range, 1.7-2.1) and therefore was unrelated to gestational age. In the fetuses with supraventricular tachycardia and hydrops, both diameters of the coronary sinus were increased and diminished fluctuation in size during the cardiac cycle was observed. CONCLUSIONS: The described sonographic approach provides an effective method for measurement of coronary sinus dimensions. The normative data may facilitate the detection of coronary sinus dilation as an indirect marker for abnormalities in venous return to the heart.

Diastole↗

PubMed2002

Evaluation of the fetal coronary circulation.

Prenatal ultrasound today allows the detailed study of small caliber vascular beds including the fetal coronary arteries and the coronary sinus. The coronary circulation is unique because of its critical role in myocardial metabolism and function and its ability to adapt in many fetal conditions. The ultrasound examination techniques for the evaluation of the fetal coronary circulation are presented. Evaluation of the coronary arteries is primarily achieved by color flow imaging and pulsed wave Doppler. Conditions such as fetal growth restriction, anemia, ductus arteriosus constriction and bradycardia are associated with evidence of enhanced coronary blood flow. These findings suggest that short-term autoregulation and long-term alterations in myocardial flow reserve are present in the human fetus. At present, examination of coronary sinus blood flow has limited clinical utility, while increases of the coronary sinus diameter or attenuation of coronary sinus dynamics may provide useful markers of abnormalities of central venous drainage. Abnormal vascular connections between the coronary arteries and the ventricular cavities may be observed in outflow tract obstructive cardiac lesions. In these conditions prenatal detection of coronary fistulae may have a potential impact on outcome and therefore counseling and perinatal management.

Coronary Circulation↗

PubMed2001

The sequence of changes in Doppler and biophysical parameters as severe fetal growth restriction worsens.

OBJECTIVE: To test the hypothesis that hemodynamic changes depicted by Doppler precede deteriorating biophysical profile score in severe intrauterine growth restriction. METHODS: Intrauterine growth-restricted fetuses with elevated umbilical artery Doppler pulsatility index (PI) > 2 standard deviations above mean for gestational age and birth weight < 10th centile for gestational age were examined longitudinally. Fetal well-being was assessed serially with five-component biophysical profile scoring (tone, movement, breathing, amniotic fluid volume and non-stress test) and concurrent Doppler examination of the umbilical artery, middle cerebral artery and ductus venosus, inferior vena cava and free umbilical vein. For fetuses with a final biophysical profile score < 6/10, progression of biophysical profile scoring, arterial PI and venous peak velocity indices were analyzed longitudinally. Gestational age effect was removed by converting indices to Z-scores (deviation from gestational age mean, in standard deviations). RESULTS: Forty-four of 236 intrauterine growth-restricted fetuses (18.6%) required delivery for abnormal biophysical profile scoring. The median gestational age at entry was 25 weeks and 1 day and at delivery was 29 weeks and 6 days. The median interval between examinations was 1.5 days and the majority had daily testing in the week prior to delivery. Between first examination and delivery, significant deterioration was observed for Doppler criteria (chi-square, P < 0.001) and biophysical parameters (Fisher's exact, P = 0.02) predominantly confined to the week prior to delivery/stillbirth. Doppler variables changed first. In 42 fetuses (95.5%), one or more vascular beds deteriorated, accelerating especially in the umbilical artery and ductus venosus at a median of 4 days before biophysical profile scoring deteriorated. Two to 3 days before delivery, fetal breathing movement began to decline. The next day, amniotic fluid volume began to drop. Composite biophysical profile score dropped abruptly on the day of delivery, with loss of fetal movement and tone. Three principal patterns of Doppler deterioration were observed: (i) worsening umbilical artery PI, advent of brain sparing and venous deterioration (n = 32, 72.7%); (ii) abnormal precordial venous flows, advent of brain sparing (n = 6, 13.6%); and (iii) abnormal ductus venosus only (n = 4, 9.1%). In the majority (31, 70.5%), Doppler deterioration was complete 24 h before biophysical profile score decline. In the remainder (11, 25%), Doppler deterioration and biophysical profile score < 6/10 were simultaneous. CONCLUSION: In the majority of severely intrauterine growth-restricted fetuses, sequential deterioration of arterial and venous flows precedes biophysical profile score deterioration. Adding serial Doppler evaluation of the umbilical artery, middle cerebral artery and ductus venosus to intrauterine growth restriction surveillance will enhance the performance of the biophysical score in the detection of fetal compromise and therefore optimizing the timing of intervention.

Delivery, Obstetric↗

PubMed2001

Fetal hydrops and hepatosplenomegaly in the second half of pregnancy: a sign of myeloproliferative disorder in fetuses with trisomy 21.

OBJECTIVE: To demonstrate the relationship between fetal hydrops and/or hepatosplenomegaly in the second half of pregnancy with a myeloproliferative disorder in fetuses with trisomy 21 or mosaic trisomy 21. DESIGN: A retrospective case series. SUBJECTS: Cases were selected from 79 cases of trisomy 21 diagnosed in our prenatal unit between 1993 and 1999. METHODS: All fetuses had a detailed sonographic anatomic survey and biometry. Doppler of the umbilical and middle cerebral arteries, ductus venosus, inferior vena cava and umbilical vein was performed whenever possible. Two-dimensional echocardiography supplemented by color Doppler flow mapping and spectral pulsed wave Doppler was performed in all cases of fetal hydrops. Fetal karyotyping was obtained by amniocentesis, chorionic villus sampling or fetal blood sampling. In the presence of fetal hydrops a cordocentesis was performed for fetal hematology, biochemistry and TORCH serology. In cases with diagnosis of myeloproliferative disorder, peripheral blast cells were characterized by microscopy, cytochemistry and determination of surface markers. All cases with myeloproliferative disorder were stillborn and subsequently had a postmortem examination performed. RESULTS: During the study period 79 cases of trisomy 21 were diagnosed. Eleven of these had fetal hydrops. Three of these fetuses presented with hepatosplenomegaly and myeloproliferative disorder in the second and third trimesters. In addition, one fetus with sonographic markers of trisomy 21, where karyotyping was unfortunately unsuccessful, presented with hepatosplenomegaly, hydrops and myeloproliferative disorder. In the four fetuses with hepatosplenomegaly and hydrops, serology was negative for congenital infection. The characteristics of blast cells in the peripheral blood smear revealed a myeloproliferative disorder. CONCLUSION: Fetal hydrops and/or hepatosplenomegaly in the second half of pregnancy, although suggestive of infectious etiology, may be a sign of myeloproliferative disorder in fetuses with trisomy 21 or mosaic trisomy 21. There is a possibility that a transient myeloproliferative disorder is a more common cause of mid or late-trimester hydrops in cases of trisomy 21 than previously thought. In these hydropic fetuses the prognosis seems to be poor. On the other hand we can speculate that a myeloproliferative disorder and the associated hepatosplenomegaly and/or hydrops may show spontaneous remission or that the transient myeloproliferative disorder may be without any detectable ultrasonographic signs and therefore may be more frequent in utero than realized.

Adult↗

PubMed2001

Prenatal diagnosis of ventriculocoronary fistula.

BACKGROUND: Cardiac anomalies may be associated with abnormal coronary vascular connections. We report the prenatal diagnosis of ventriculocoronary fistula in three fetuses with associated cardiac anomalies. MATERIALS AND METHODS: Fetal echocardiography was performed in three patients referred for suspected cardiac anomaly. Two-dimensional fetal echocardiography was complemented by color Doppler flow imaging and spectral Doppler in all cases. RESULTS: A ventriculocoronary fistula was diagnosed in three patients referred at 22, 23 and 32 weeks. The first patient had hypoplastic left heart associated with transposition of the great arteries and pulmonary atresia with an intact interventricular septum. The coronary fistula arose from the transposed aorta to the left ventricle. In two patients ventriculocoronary fistula was found in association with pulmonary atresia and an intact interventricular septum. In all cases there was bidirectional flow within the fistula (diastolic blood flow towards the ventricle with reversal during ventricular systole). The pregnancy with hypoplastic left heart with transposition, and one of those with pulmonary atresia resulted in neonatal death and stillbirth, respectively. In the third instance the ventriculocoronary fistula was verified by postpartum cardiac angiography. The infant initially received a Blalock-Taussig shunt, subsequently replaced by a bidirectional Glenn shunt, and was doing well at the time of writing. CONCLUSION: A ventriculocoronary fistula can be identified prenatally by color and spectral Doppler. This anomaly should be sought in fetuses with outflow tract obstructive cardiac lesions and an intact interventricular septum. Prenatal diagnosis allows early angiography postnatally. Delineation of coronary vascular regions may therefore facilitate preoperative planning.

Adult↗

PubMed2001

Antenatal assessment of the growth restricted fetus.

Babies who are small due to intrauterine growth restriction are at higher risk for poor perinatal and long-term outcome than those who are appropriately grown. Through multiple antenatal testing modalities a sequence of deteriorating fetal status can be documented in such cases. The nature of this compromise is best reflected by the combination of fetal biometry, biophysical profile scoring and arterial and venous Doppler. This combination accurately defines fetal states and therefore risk of stillbirth or poor transition to extrauterine life. In the preterm neonate, fetal factors, gestational age and neonatal course interact significantly to impact on short- and long-term outcomes. The potential for iatrogenic prematurity is great and ongoing appraisal of peripartum management is critical. An integrated management protocol accounting for these factors is examined in this review.

Amniotic Fluid↗

PubMed2000

Umbilical artery doppler screening for detection of the small fetus in need of antepartum surveillance.

OBJECTIVE: Our goal was to test the hypothesis that umbilical artery Doppler velocimetry identifies fetuses who are small for gestational age and in need of antenatal surveillance. STUDY DESIGN: Three hundred eight fetuses with either an ultrasonographic weight estimate <10th percentile for gestational age or an abdominal circumference <2.5th percentile for gestational age or both of these had an umbilical artery Doppler measurement of the systolic/diastolic ratio. A systolic/diastolic ratio >90th percentile for gestation was considered abnormal. The incidences of a birth weight <10th percentile, fetal distress, and metabolic acidemia were recorded for both groups (normal vs abnormal umbilical artery Doppler). RESULTS: Only the umbilical artery systolic/diastolic ratio predicted perinatal outcome in the group of fetuses who were presumed to be small for gestational age. Those 138 fetuses with elevated umbilical artery systolic/diastolic ratios had lower umbilical artery and vein pH values at birth (artery, 7.23 +/- 0.08 vs 7.25 +/- 0.1; P <.02; vein, 7.31 +/- 0.01 vs 7.34 +/- 0.09; P =.01), an increased likelihood of fetal distress consistent with chronic hypoxemia (26.3% vs 8.6%; P <.0001), more admissions to the neonatal intensive care unit (40.7% vs 30.7%; P <.005), and a higher incidence of respiratory distress (66% vs 27.3%; P <.03). However, it is important that no fetus with a normal Doppler flow measurement was delivered with a metabolic acidemia associated with chronic hypoxemia. Further, the likelihood of a false-positive diagnosis of intrauterine growth restriction was increased in the group with a normal umbilical artery Doppler resistance. CONCLUSION: Antenatal surveillance may be unnecessary in fetuses with suspected intrauterine growth restriction if the umbilical artery systolic/diastolic ratio and amniotic fluid volume are normal, because the complications that occur are intrapartum. If these findings are confirmed in prospective trials, the cost implication of reducing the number of antenatal surveillance tests administered in this group of patients is great.

Abdomen↗

PubMed2000

Absent umbilical artery end-diastolic velocity in growth-restricted fetuses: a risk factor for neonatal thrombocytopenia.

OBJECTIVE: To examine the relationship between umbilical artery (UA) end-diastolic flow and neonatal thrombocytopenia. METHODS: We prospectively examined 115 anatomically normal single fetuses with UA pulsatility indices more than two standard deviations above the gestational age mean and subsequent birth weights below the tenth percentile. Peripheral neonatal platelet counts in fetuses with positive UA end-diastolic velocity were compared with those of fetuses with absent or reversed UA end-diastolic velocity. RESULTS: Sixty-seven fetuses (58.3%) had positive UA end-diastolic velocity and 48 (41.7%) had absent or reversed UA end-diastolic velocity. Three neonates in the positive-flow group and 22 neonates in the absent- or reversed-flow group had platelet counts of less than 100, 000/mm(3) (relative risk 10.2; 95% confidence interval; 3.2, 32.3; P <.001). Absent or reversed end-diastolic velocity had a sensitivity of 88%, specificity of 71%, positive predictive value of 46%, and negative predictive value of 96% for predicting neonatal thrombocytopenia. Neonates with absent or reversed flow also had lower median platelet counts (101,500/mm(3) versus 208,000/mm(3), P <.001), hemoglobin levels (15.1 versus 16.4 g/dL, P <.01), and hematocrits (47.6 versus 51.1%, P <.05), as well as higher nucleated red blood cell counts (191 versus 15 per 100 white blood cells, P <. 001). CONCLUSION: Absent or reversed UA end-diastolic velocity in growth-restricted fetuses is associated with a statistically significant increase in risk of neonatal thrombocytopenia.

Adolescent↗

PubMed2000

Gray scale and color Doppler sonography in the third stage of labor for early detection of failed placental separation.

OBJECTIVE: The purpose of this study was the characterization of normal and abnormal third stage placental separation using gray scale and color Doppler sonography. METHODS: The third stage of labor was examined in 62 patients using gray scale and color Doppler sonography. After identification of placental basal plate vessels by color Doppler sonography, the placentation site was examined throughout the third stage with combined gray scale and color Doppler mode. Placental separation from the myometrium was defined clinically and correlated to cessation of color Doppler detected blood flow in basal plate vessels. RESULTS: Three sonographic phases of placental separation were: (1) latent = interval between delivery of the fetus and beginning placental separation; (2) detachment = mono- or multiphasic shearing off of the placenta and (3) expulsion = interval between completed separation and vaginal delivery of the placenta. In 57 cases with clinically normal placental separation blood flow between placenta and myometrium ceased immediately after delivery of the fetus during the latent period. In five cases manual or instrumental removal was necessary because of placenta adhaerens in one case and placenta accreta in four cases. The latter showed maternal blood flow from the myometrium deep into the placenta beyond the latent phase. CONCLUSION: Cessation of blood flow between the basal placenta and myometrium following delivery of the baby is the sonographic hallmark of normal placental separation. Persistent blood flow demonstrated by color Doppler sonography is suggestive of placenta accreta.

Adult↗

PubMed2000

Circulatory effects of acute bradycardia in the human fetus as studied by Doppler ultrasound.

OBJECTIVE: To report on flow changes in fetal arterial, venous and coronary vessels during bradycardia following cordocentesis. Changes in the fetal circulation in response to acute challenges are incompletely understood. METHODS: Fetal blood sampling was performed at 29 + 4 weeks for chromosome analysis in a fetus with multiple malformations including a complete atrioventricular septal defect with competent atrioventricular valve. The procedure was complicated by a 12-min bradycardia of 57 beats/min. 'Heart sparing' (sudden visualization of coronary blood flow) and 'brain sparing' (increased diastolic velocities in the middle cerebral artery) were demonstrated by Doppler examination despite marked circulatory compromise (regurgitation of atrioventricular valve, increased reverse flow in precordial veins and pulsatile umbilical vein flow pattern) which persisted after normalization of the fetal heart rate. The findings had resolved completely at a full cardiovascular examination 6 h after the bradycardia. Pregnancy termination was subsequently performed for partial monosomy 13q. CONCLUSION: Protective fetal changes producing 'heart sparing' and 'brain sparing' and may be operational during episodes of acute fetal bradycardia.

Acute Disease↗

PubMed2000

Coronary artery blood flow visualization signifies hemodynamic deterioration in growth-restricted fetuses.

OBJECTIVE: To determine the relationship between fetal coronary blood flow (CBF) visualization in intrauterine growth restriction (IUGR), longitudinal changes in arterial and venous flow velocity waveforms and perinatal outcome. METHODS: A total of 48 IUGR fetuses (abdominal circumference below the 5th percentile for gestational age) with absent or reversed umbilical artery (UA) end-diastolic velocity (AREDV) were examined longitudinally by echocardiography attempting CBF visualization at each examination. Doppler evaluation of the middle cerebral artery, inferior vena cava (IVC), ductus venosus (DV) and umbilical vein (UV) was performed at each examination. Doppler measurements were correct for gestational age by conversion into Z-scores (delta-indices). Doppler results and outcome from fetuses in which CBF was visualized (group 1, n = 20) and those in which CBF was never visualized (group 2, n = 28) were compared. Outcome parameters analyzed included Apgar scores, cord arterial blood gases, perinatal mortality, respiratory distress, bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis and postpartum circulatory failure requiring pressor support. RESULTS: There was no difference in Doppler indices between groups at study entry. CBF visualization coincides with a significant increase of UA-, IVC- and DV delta-indices. The greatest rate of change was observed for indices in the ductus venosus which occurred in the 24 h preceding CBF visualization. Group 1 fetuses required earlier delivery (median 27 + 4, vs. median 30 + 0), had lower birthweight (682 +/- 305 g vs. 936 +/- 416 g), lower cord pH (7.21 +/- 0.1 vs. 7.27 +/- 0.06) and cord pO2 (13 +/- 4.5 vs. 24.1 +/- 13.5 mmHg) compared to group 2 (all values P < 0.05). Mortality was similar (group 1 = 6/20, 30%; group 2 = 6/28, 21.4%). CONCLUSIONS: In IUGR, fetuses with AREDV and centralization are at high risk for hypoxemia, acidemia and adverse outcome. CBF visualization coincides with deteriorating venous flows. Operator dependence of CBF visualization and the strong association with abnormal venous flow stresses the importance of venous Doppler surveillance in these fetuses.

Blood Flow Velocity↗

PubMed2000

Relationship between arterial and venous Doppler and perinatal outcome in fetal growth restriction.

OBJECTIVE: The aim of this investigation was to assess the relationship between abnormal arterial and venous Doppler findings and perinatal outcome in fetuses with intrauterine growth restriction (IUGR). METHODS: Doppler velocimetry of the umbilical artery (UA), middle cerebral artery (MCA), inferior vena cava (IVC), ductus venosus (DV) and free umbilical vein was performed in 121 IUGR fetuses with a UA pulsatility index (PI) > 2 SD above the gestational age mean and subsequent birth weight < 10th centile for gestational age. Groups based on the last Doppler exam were: 1 = abnormal UA-PI only (n = 42, 34.7%), 2 = MCA-PI > 2 SD below the gestational age mean (= 'brain sparing') in addition to abnormal UA-PI (n = 29, 24.0%), 3 = DV or IVC peak velocity index (PVIV) > 2 SD above the gestational age mean and/or pulsatile UV flow (n = 50, 41.3%). Z-scores (delta indices) were calculated for Doppler indices. Perinatal mortality, respiratory distress (RDS), bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), circulatory failure and umbilical artery blood gases were recorded. RESULTS: Absence or reversal of umbilical artery end-diastolic flow was observed in 4 (9.5%) of fetuses in group 1, 10 (34.5%) fetuses in group 2 and 41 (82%) fetuses in group 3. A low middle cerebral artery pulsatility index was found in 39 (78%) fetuses in group 3. Multiple regression analysis with gestational age at delivery, delta indices and cord artery blood gas as independent parameters and individual perinatal outcomes as dependent variables was performed. In this analysis the association was strongest with gestational age for each complication. There were no significant differences in Apgar scores between groups. At delivery, 'brain sparing' was associated with hypoxemia and abnormal venous flows with acidemia. Perinatal mortality was highest in group 3 and stillbirth was only observed when venous flow was abnormal. All postpartum complications were more frequent in fetuses with abnormal venous flows. The only statistically significant relation between Doppler indices and outcome was the association between abnormal ductus venosus flow and fetal death (r2 = 0.24, P < 0.05). CONCLUSION: Growth restricted fetuses with abnormal venous flow have worse perinatal outcome compared to those where flow abnormality is confined to the umbilical or middle cerebral artery. In fetuses with low middle cerebral artery pulsatility, venous Doppler allows detection of further deterioration. While abnormal venous flows can be significantly associated with fetal demise, gestational age at delivery significantly impacts on all short-term outcomes.

Analysis of Variance↗