Use of Doppler ultrasound in the management of uteroplacental perfusion during cardiopulmonary bypass in pregnancy.

Cardiopulmonary bypass, the extreme of non-obstetric surgery during pregnancy, presents unique challenges to minimize maternal and fetal risk. We present our experience with a woman who was diagnosed with a left atrial myxoma following an ischemic cerebrovascular accident. We discuss clinical management specific to cardiopulmonary bypass during pregnancy and delivery in the context of a multidisciplinary team approach. We recommend using intermittent Doppler ultrasound as a non-invasive real-time assessment of uteroplacental perfusion during non-obstetric surgery in pregnancy. Monitoring of perfusion facilitates active feedback for appropriate in utero resuscitation in these cases.

Biodistribution, with high uptake by the reproductive tract, of an intraperitoneally infused radiohalogenated steroidal estrogen-receptor ligand.

We infused [123I]16 alpha-(123I)-iodo-estradiol ([123I]E2) intraperitoneally (i.p.) into swine to study its biodistribution and to explore the i.p. use of radiohalogenated steroid estrogen-receptor (ER) ligands as a potential option for diagnosing and treating intra-abdominal, retroperitoneal, and distant sites of advanced ER-rich malignancies. Fifty to 80% of the radiolabel was absorbed from the peritoneal cavity within 30 minutes, and 30 to 50% of the infused radiolabel was excreted in the urine within 2 hr. The rate of biliary clearance was maximal within 25 minutes. At 3 hr, the ER-rich reproductive tract had greater than 63 times the concentration of radiolabel in blood; the former was blocked by non-labeled competitors for ER. Uptake by non-ER-rich tissues, compared to blood, ranged from 0.7:1 (heart and lungs) to 16:1 (spleen); the omentum, however, exhibited a concentration as high as 64:1, which was not blocked by non-labeled ER ligands. Uptake by ER-rich target tissue remained high when charcoal was used to prevent reabsorption of radiolabel from the digestive tract after its biliary excretion, and when the products of biliary excretion were removed by catheterization of the common bile duct. Neither charcoal nor exteriorization of bile appeared to affect urinary clearance of the radiolabel over the time course of the experiments. Taken together with the recent development of syntheses that yield radiohalogenated sex steroid receptor ligands of high specific activity, our findings are encouraging for the potential application of radiolabeled ligands as i.p. administered pharmaceuticals. The advantage of the i.p. route is that it provides direct uptake of the pharmaceutical by free-floating clusters and individual cancer cells in ascitic fluid, as well as delivery via the circulation to vascularized intra- and/or extraperitoneal metastases.

Prenatal diagnosis of nonrhizomelic chondrodysplasia punctata (Conradi-Hünermann syndrome).

Chondrodysplasia punctata has been classified into two major types including the rare autosomal recessive "rhizomelic type" and a more common but genetically heterogenous nonrhizomelic type (referred to by some authors as "Conradi-Hünermann (CH) type"). The former is typically lethal, manifesting serious anomalies, and allowing several instances of confident prenatal diagnosis. The latter being milder has more subtle anomalies and prenatal diagnosis has been uncommonly reported (confined to cases diagnosed incidentally by flat-plate X-ray examination of the mother in late third trimester, and a case found by directed ultrasound performed in a Mendelian affected mother). Cases included 1) a young primigravida thought to be affected with Conradi-Hünermann syndrome presented at 16 weeks gestation for prenatal diagnosis and counseling. Ultrasound examination of the fetus detected assymetric limb shortness allowing the presumptive diagnosis of an affected fetus which was confirmed after delivery near term. 2) A normal 38-year-old multipara with unremarkable family history underwent routine fetal ultrasound evaluation at 18 weeks gestation. Disorganization of the spine, premature echogenicity of femoral epipheses, and frontal bossing with depressed nasal bridge were described. Neonatal examination confirmed suspicion of CH. Case 1 demonstrates the importance of solid clinical diagnosis in Mendelian malformation-affected parents for directing prenatal diagnostic efforts. Case 2 represents the first index case of CH diagnosed antenatally by ultrasound. Diagnostic clues which must be considered in establishing these diagnoses are discussed, as are some of the difficulties and limitations in antenatal counseling such cases.

Two consecutive hydrolethalus syndrome-affected pregnancies in a nonconsanguinous black couple: discussion of problems in prenatal differential diagnosis of midline malformation syndromes.

Hydrolethalus syndrome is a rare autosomal recessive (AR) disorder characterized by polyhydramnios, CNS abnormalities, cleft lip/palate, micrognathia, and polydactyly. Its molecular basis is unknown and prenatal diagnosis is challenging due to phenotypic overlap with several other midline malformation syndromes. A 34-year-old G3P2, nonconsanguinous, married, African-American woman was referred at 19 weeks of gestation after ultrasound findings of "multiple congenital anomalies." A previous pregnancy had been terminated following ultrasound findings of polyhydramnios, cleft lip/palate, polydactyly, severe hydrocephalus, and a Dandy-Walker malformation (DWM). Level II ultrasound evaluation of the current pregnancy demonstrated all of the anomalies which had been present in her previous pregnancy. Karyotype of amniocytes was 46,XX. Autopsy following pregnancy termination confirmed ultrasound findings. The pedigree, sonographic, and autopsy findings in this case were most consistent with hydrolethalus syndrome, although other AR multiple midline malformation syndromes were considered. Our case was detected by 19 weeks. Confident differential diagnosis is difficult for the geneticist and even more so for the sonologist given the technical limitations of ultrasound. It is uncertain whether these mendelian midline malformation syndromes represent slightly different phenotypic expressions of a common genetic defect or are manifestations of allelic and or locus heterogeneity. We suggest that for prenatal diagnostic purposes, in the absence of knowledge of the molecular basis of these disorders, the fine distinctions are not crucial as long as their mendelian inheritance is recognized and presence or absence of manifestations which make them severe are ascertained.

Familial omphalocele: considerations in genetic counseling.

Nonsyndromal omphalocele is generally regarded as a sporadic malformation. Recurrence risk is considered negligible. We report on a patient in whom 5 consecutive pregnancies (by 2 separate nonconsanguineous partners) were complicated by omphalocele as an isolated defect. Neither the patient nor her partners had history of relatives with omphalocele, although the patient's brother and his son had large umbilical hernias requiring repair in infancy. Some familial cases of nonsyndromal omphalocele have been previously reported; most such pedigrees suggest vertical transmission, although there are a few cases with only a single generation involved. In our case, the multigenerational finding of ventral wall hernias makes an autosomal dominant mechanism with variable expressivity a tenable explanation. The collected instances of familial nonsyndromal omphalocele emphasize omphalocele heterogeneity and caution in counseling recurrence risks.

Triply discordant triplets: probability, management options, and risks.

The spontaneous occurrence of triplets is rare. With increased utilization of "assisted reproductive technologies," multifetal gestations have become more common. The empiric fetal risk for major malformation is approximately 3%. In a triplet pregnancy each fetus independently carries this risk so that the probability of having at least one malformed fetus is approximately 9%. It is much less likely to have 2 or 3 simultaneously but discordantly malformed fetuses in a multizygotic triplet gestation (.09% and .0027% risk, respectively). We report on the first case, to our knowledge, of an ovulation-stimulated triplet pregnancy complicated by 3-way discordance for major malformations diagnosed in the late second trimester by ultrasound. Fetus A was affected by congenital diaphragmatic hernia and trisomy 21; fetus B had encephalocele, a midline facial defect, and a cleft palate; and fetus C had evidence of unilateral claw hand but an otherwise normal fetal survey. At 19 weeks of gestation, fetus A was found to have spontaneously died, and a selective termination of triplet B was performed. We conclude: (1) the finding of a single major malformation in one fetus should lead to extensive search for malformations in all members of the pregnancy, and (2) the simultaneous occurrence of major malformations in more than one member of a multifetal gestation is a circumstance under which multiple selective termination deserves consideration. In this article we discuss important issues and caveats in the performance of selective termination for abnormal members of multifetal gestations.

Gastroschisis: can antenatal ultrasound predict infant outcomes?

OBJECTIVE: To test previously proposed but unproven antenatal ultrasound prognostic criteria in fetal gastroschisis. METHODS: Thirty consecutive gastroschisis-affected pregnancies and their outcomes were reviewed retrospectively. Data were tabulated by review of antenatal ultrasound videotapes, with blinded comparison to indicators of short- and long-term infant outcomes obtained from the medical records. Criteria of previous reports were applied to these data, focusing on their ability to prognosticate effectively. RESULTS: Applying a criterion of 10 mm bowel dilatation proved minimally useful in prognosticating infant outcomes. However, a stricter 17-mm criterion for clinically important bowel dilatation provided prognostic information, with remarkable improvement in specificity (75 versus 37%) and positive predictive value (55 versus 37%) for infant morbidity, with comparatively little loss of sensitivity (71 versus 85%). CONCLUSIONS: Bowel dilated more than 17 mm on antenatal ultrasound appears to be associated with increased short- and long-term infant morbidity. Whether this finding warrants obstetric intervention in the preterm gastroschisis-affected pregnancy with substantial bowel dilatation remains to be determined.

Spontaneous resolution of nonimmune hydrops fetalis secondary to human parvovirus B19 infection.

Many instances of nonimmune hydrops fetalis ascribed to human parvovirus B19 have been reported. The leading proposed pathophysiologic mechanism of hydrops in affected fetuses is viral invasion of red blood cell progenitors, causing a profound reticulocytopenic fetal anemia. Although the natural history of fetal parvovirus infection remains to be elucidated fully, there have been recent reports of funipuncuture and intrauterine blood transfusions to diagnose and manage this problem. We report two pregnancies in which parvovirus-related hydrops fetalis was observed to resolve without intervention, followed by uncomplicated vaginal deliveries of healthy infants. These observations emphasize the need for further investigation before recommending routine fetal blood transfusion in affected cases.

Fetal intracardiac potassium chloride injection to avoid the hopeless resuscitation of an abnormal abortus: II. Ethical issues.

Following the diagnosis of a genetic anomaly, some couples choose to have a legal abortion. However, following later abortions at greater than 20 weeks, the rare but catastrophic occurrence of live births can lead to fractious controversy over neonatal management. To avoid this situation, we have added fetal intracardiac potassium chloride injection to cause fetal cardiac arrest before induction of labor. The ethical issues surrounding such a practice are complex. We support this practice for three reasons: 1) The women's decision for abortion is protected because this practice assures her right for non-interference; 2) potential psychological harm to the patient and other family members is avoided; and 3) the potential for coercive intervention by other health care personnel is eliminated. At least three objections can be raised: 1) All abortions are unjust; 2) newborns and second-trimester fetuses at similar weights with identical defects should be managed in like fashion; and 3) the patient is not entitled to death of the fetus, only to evacuation of the uterine contents. On balance, we believe that our approach is justifiable ethically as it reduces the burden of conflict between the wishes of the patient and those of the neonatal care givers. It should be introduced only in situations in which the likelihood of civil or criminal liability or unwarranted medical intervention is high.

Perinatal death and tocolytic magnesium sulfate.

OBJECTIVE: To determine whether there is a significant association between perinatal mortality and exposure to total doses of tocolytic magnesium sulfate larger than 48 g. METHODS: We did a case-control study in which cases were defined as neonates or fetuses who died after being exposed to tocolytic magnesium sulfate and controls were those who survived exposure. The study included fetuses and neonates who weighed between 700 and 1249 g and whose mothers had received tocolytic magnesium sulfate at Chicago Lying-in Hospital between January 1, 1986, and March 31, 1999. We excluded women who received prophylactic magnesium sulfate for preeclampsia or preeclampsia superimposed on chronic hypertension, and fetuses or neonates with major congenital anomalies. Data were analyzed by Fisher exact test, chi(2) test, Student t test, Mann-Whitney U test, multivariable logistic regression, and Cochrane-Armitage trend test. RESULTS: Controlling for birth weight or gestational age, year of delivery, receipt of betamethasone, acute maternal disease, and maternal race in a multivariable model, we found that exposure to total doses of tocolytic magnesium sulfate exceeding 48 g was significantly associated with increased perinatal mortality (adjusted odds ratio 4. 7; 95% confidence interval 1.1, 20.0; P =.035). Using the Cochrane-Armitage trend test, we found that a significant dose response was present (P =.03), but one that was most consistent with a threshold effect. CONCLUSION: Our findings support the hypothesis that high doses of tocolytic magnesium sulfate are associated with increased perinatal mortality among fetuses and neonates weighing 700-1249 g.

Umbilical cord serum ionized magnesium level and total pediatric mortality.

OBJECTIVE: To estimate whether higher magnesium levels in umbilical cord blood at delivery are associated with increased total pediatric (fetal + neonatal + postneonatal) mortality. METHODS: During the Magnesium and Neurologic Endpoints Trial, in addition to randomizing mothers having preterm labor into arms containing magnesium sulfate, other tocolytic agents, or saline controls, we obtained biologic specimens at delivery, including umbilical cord venous blood on which was determined the serum ionized magnesium level using the AVL 988-4 analyzer (Graz, Austria). Laboratory results were then matched with the pediatric mortalities. The study power was based on the anticipated reductions in neonatal intraventricular hemorrhage related to magnesium usage from 18.9% to 4.4%. For alpha =.05, 1-beta (power)=80%, two tailed, the total number of infants needed would be 140. RESULTS: Of 149 mothers who gave permission for randomization, ionized magnesium levels were available for 82 children. Seven deaths occurred (one immediately before delivery, three as neonates, and three in the postneonatal period). The median level of ionized magnesium among the seven dead children was 0.76 mmol/L; among the 75 survivors, the median level of ionized magnesium was 0.55 mmol/L (Mann-Whitney U test, P =.03). Using multivariable logistic regression analysis, the association remained statistically significant when controlling for possible confounding factors (adjusted odds ratio 7.7, 95% confidence interval 1.2, 47.6, P =.03). CONCLUSION: These findings of a dose response between serum ionized magnesium and deaths in children increase our concern about the improper use of tocolytic magnesium.

Chorionic villus sampling: transabdominal versus transcervical approach in more than 4000 cases.

OBJECTIVE: To address the evolving trends in the choice of transabdominal or transcervical chorionic villus sampling (CVS) at a teaching hospital and to evaluate the influence of gestational age on the approach chosen. METHODS: We analyzed our CVS data base, which contained information from 1986-1991. The proportions of transabdominal and transcervical CVS were tabulated for each year. In addition, the distribution of the CVS approaches over the various gestational ages was examined. RESULTS: During the study period, 4290 CVS procedures were performed. The rate of the transabdominal technique was stable at about 15% per year except for the first 2 years, when essentially all procedures were transcervical. Use of transabdominal CVS increased with advancing gestational age, from 3.6% at less than 10 weeks' gestation to 97.6% at greater than 14 weeks (chi 2 = 120, P less than .001; r = 0.791). CONCLUSIONS: The choice between the transabdominal and transcervical approach to CVS largely reflects the route emphasized during the physician's training. When choice is based strictly on technical limitations due to placental position, the overall transabdominal CVS rate is approximately 15%. A shift from transcervical to transabdominal CVS occurs with increasing gestational age as the placenta gains bulk and moves away from the cervix. After 14 weeks' gestation, most procedures are performed transabdominally.

Determinants of parental decision to abort or continue after non-aneuploid ultrasound-detected fetal abnormalities.

OBJECTIVE: This study evaluated factors influencing the decision to abort after abnormalities in the karyotypically normal fetus were found through ultrasonography. METHODS: We reviewed all pregnancies complicated by ultrasound-detected abnormalities managed on our service from April 1990 through August 1991 (N = 262). Cases with associated karyotypic abnormalities were excluded (N = 35), as were cases diagnosed after the legal gestational age limit for abortion (N = 68). The remaining 159 cases were stratified into prognosis groups of "severe," "uncertain," and "mild." RESULTS: The prognostic severity of the ultrasound abnormality strongly correlated with the decision to abort (P less than .0001). Rates of termination were 0, 12, and 66% in the "mild," "uncertain," and "severe" groups, respectively. The patients' age, gravidity, and parity, and the fetal gestational age at diagnosis did not differ significantly between the groups. CONCLUSIONS: 1) In non-aneuploid pregnancies with an ultrasound diagnosis of fetal abnormality, the major predictor of the decision to abort was the severity of fetal prognosis. 2) The gestational age at diagnosis was not an important variable in the decision to abort for fetal structural abnormalities. 3) Parents who had fetuses with abnormalities associated with uncertain prognoses usually opted to continue the pregnancy. This appeared to be particularly true for defects that were potentially correctable in utero or by neonatal intervention (even if investigational).

Fetal intracardiac potassium chloride injection to avoid the hopeless resuscitation of an abnormal abortus: I. Clinical issues.

OBJECTIVE: With the intention of preventing the attendant medical, ethical, and legal problems arising from the birth of live-born, anomalous fetuses, we initiated a program offering fetal intracardiac potassium chloride injection as an adjunctive measure in the setting of genetically indicated second-trimester abortion. METHODS: A lethal fetal injection was offered to patients carrying chromosomally or structurally abnormal fetuses at 19-24 weeks' gestation who desired abortion. When the patient elected this procedure, real-time ultrasound guidance was used to inject 3-5 mL of potassium chloride (2 mEq/mL) directly into the fetal cardiac chambers, followed by observation of fetal heart activity to ascertain cessation. Labor was subsequently induced with uterotonic prostaglandins. RESULTS: The procedure caused immediate cessation of fetal heart motion in 20 of 21 cases. There were no maternal complications. No fetuses were live-born. CONCLUSIONS: Direct fetal intracardiac potassium chloride injection effectively causes immediate fetal cardiac arrest. This approach may be adopted in cases of abortion by labor-induction methods at advanced gestations to ensure that the abortus is stillborn.

Maternal neurosurgical shunts and pregnancy outcome.

OBJECTIVE: To assess pregnancy outcome in women with ventriculoperitoneal or lumboperitoneal shunts. METHODS: Charts were reviewed retrospectively for mothers with ventriculoperitoneal or lumboperitoneal shunts delivered at Hutzel Hospital from 1976-1992. Patients were identified by cross-referencing medical records from Children's Hospital Neurosurgical Division and medical records at Hutzel Hospital during this period. RESULTS: Eight patients with 25 pregnancies were identified from 1976-1992. Indications for shunt placement were pseudotumor cerebri (four with lumboperitoneal shunts) and congenital hydrocephalus (four with ventriculoperitoneal shunts). Pregnancy outcomes were two elective abortions, five spontaneous abortions, two preterm vaginal deliveries, one mid-forceps rotation, two primary low transverse cesareans, two repeat low transverse cesareans, and 11 spontaneous vaginal deliveries. No patient received prophylactic antibiotics during labor and vaginal delivery because of the shunt. There were no shunt-related complications. CONCLUSIONS: This series doubles the number of previously reported pregnancy outcomes in women with neurosurgical shunts. Contrary to the literature suggesting cesarean delivery and prophylactic antibiotics for all patients, our experience suggests that vaginal delivery can be considered and that prophylactic antibiotics are not an absolute necessity in uncomplicated vaginal deliveries.

Adverse and beneficial effects of tocolytic therapy.

In addition to questions raised about the efficacy of many tocolytics, appropriate concern has been voiced about the safety of these potent drugs. Although some degree of risk for adverse effects with drugs promising a strong therapeutic effect can be accepted, caution needs to be exercised when benefits are marginal or unproven. Unfortunately, some of the tocolytics, most notably the betamimetics and magnesium sulfate, have been found to have considerable potential for adverse maternal cardiovascular and respiratory effects. Although less clearly established, the use of indomethacin appears to be associated with increased fetal and neonatal risks. Concerning magnesium sulfate, in addition to the well-known maternal effects, the accumulating evidence showing an increased frequency of adverse outcomes in the fetus and neonate has led to the recommendations to abandon its use entirely as a tocolytic. Given the limitations of our current state of knowledge, nifedipine would appear to be among the more efficacious and safer tocolytics available to use when properly indicated.

Platelet activating factor-acetylhydrolase activity following chorionic villus sampling and amniocentesis.

OBJECTIVE: Platelet activating factor (PAF) is essential for embryonic development and is a potent vasodilator. It increases vascular permeability and stimulates prostaglandin E2 (PGE2) production. Platelet activating factor-acetylhydrolase (PAF-AH), the enzyme that degrades PAF, is synthesized by decidual macrophages. The aim of this study was to test the hypothesis that chorionic villus sampling (CVS) and/or amniocentesis might cause an increase in maternal PAF-AH activity. METHODS: Maternal plasma PAF-AH activity was evaluated before and after genetic amniocentesis (N = 13) and transcervical CVS (N = 29). A control group (N = 9) was evaluated to study the effects of venipuncture. RESULTS: Chorionic villus sampling caused a significant elevation in PAF-AH activity (P < .0005). No changes were noted in PAF-AH activity in the amniocentesis or the control group. CONCLUSIONS: Chorionic villus sampling causes subclinical release of PAF-AH, possibly from the decidual macrophages. Increased PAF-AH activity might result in decreased PAF levels, which might lead to vasoconstriction in the placental circulation due to lack of the vasodilator effects of PAF and possibly PGE2. This mechanism might explain the increased risk for fetal limb reduction noted with CVS performed at very early gestational ages.

Hyperemesis gravidarum. Effects on fetal outcome.

OBJECTIVE: To study perinatal outcomes in pregnancies complicated by hyperemesis gravidarum (HG) as compared to controls. STUDY DESIGN: Between 1984 and 1991, 138 patients were diagnosed with HG according to Fairweather's criteria. Subjects were stratified into groups of mild and severe HG according to the presence of at least one of the following criteria: ketonuria, increased blood urea nitrogen and hematocrit, and/or abnormal electrolytes. All patients without HG on whom records were available and who delivered during the study period were included as controls. Multiple gestations and stillbirths were excluded from the analysis. Student's t test and X2 were used for statistical analysis. RESULTS: Demographic data were not significantly different between the groups. Forty patients were diagnosed as having mild HG and 98 patients as having severe; 12,335 patients were defined as controls. Mean fetal birth weights were 3,110, 3,093, and 3,160 g in the mild, severe and control groups, respectively. The incidence of congenital anomalies was 2.5%, 2.0% and 1.6%, respectively. The incidence of prematurity was 17.5%, 11.2% and 10.7% in mild and severe HG and controls, respectively. None of the outcome variables for mild or severe HG were significantly different as compared to the controls. Differences in other neonatal outcomes, including frequency of five-minute Apgar score < 7 and neonatal intensive care unit admissions, were not significantly different between the three groups. CONCLUSION: In contrast to previous reports, this study demonstrated that fetuses of gravidas admitted for HG are not at increased risk of growth retardation, congenital anomalies or prematurity. No beneficial effect on pregnancy outcome was detected.

Constriction of the umbilical cord leading to fetal death. A report of three cases.

Constriction of the umbilical cord is characterized by localized absence of Wharton's jelly, leading to narrowing of the cord, thickening of the vascular walls and narrowing of the vascular lumens. This may result in a compromised fetal blood supply, leading to fetal anoxia and eventual fetal death. Approximately 50 cases have been reported in the world literature over the last three centuries. Three cases of umbilical cord constriction leading to intrauterine fetal demise are reported. Two of the patients presented during the late second trimester with loss of sensation of fetal movements. Intrauterine fetal demise was diagnosed, and autopsy revealed constricted umbilical cords associated with torsion. The third patient is unique in that fetal death was precipitated by a routine, technically uncomplicated, transplacental amniocentesis procedure performed in the early second trimester. At the time of termination of the pregnancy we found marked stenosis with torsion over a 1-cm segment of the umbilical cord juxtaposed against the fetal insertion site. Umbilical cord constriction is a rare, almost invariably fatal condition, usually undiagnosed antenatally. In case 3, disruption of the placenta by amniocentesis may have initiated a terminal event in a fetus already compromised by a cord constriction. Three possible mechanisms could have contributed to the fetal death after amniocentesis in the presence of cord constriction: acute vasospasm, acute oligohydramnios and uterine contraction, or an obliterating thrombus.

Color Doppler ultrasonography for distinguishing myomas from uterine contractions in pregnancy.

OBJECTIVE: To determine the applicability and reliability of color Doppler ultrasonography (US) for distinguishing a uterine myoma from a focal myometrial contraction. STUDY DESIGN: Images from 36 patients with uterine thickenings were classified as myomas when color Doppler US demonstrated no centralized flow with a circumscribed vessel pattern at the border. Thickenings were classified as focal myometrial contractions when there was demonstrable vascular flow throughout the thickening. RESULTS: Using these diagnostic criteria, images from 36 patients were reliably characterized as representing myomas or contractions. The diagnosis was made more reliable by using the lowest velocity settings and exclusion of power Doppler US in nonretroplacental lesions. CONCLUSION: Color Doppler US is a sensitive and reliable tool for distinguishing uterine myomas from focal myometrial contractions.