Experimental and clinical study on the blood supply of the subdermal vascular network island flap]

Vascular resistances of various fetal areas are assessed by Doppler ultrasound. The PI, RI and S/D indices are measured on the cerebral, renal, aortic and umbilical Doppler spectrum. Ratios of these indices based on the comparison of the cerebral (Rc) and the umbilical (Rp) resistances, or carotid (Rcc) and umbilical resistances, or cerebral (Rc) and aortic (Rao) resistances (Rc/Rp or Rp/Rcc, or Rc/Rao), measure the flow redistribution between the placenta and brain. The umbilical resistance indices, when greater than the upper limit of the normal range (> 2sd) are frequently associated with IUGR. (Sensitivity about 65 to 70%). Absent end diastolic flow is most of the time associated with severe IUGR and hypoxia and poor fetal outcome. A fairly good correlation was found between the existence of significantly decreased (< .2.sd) cerebral resistance and the development of post asphyxial encephalopathy in the neonate (Specificity 75% Sensitivity 87%). The earliest detectors of IUGR and hypoxia are the cerebral-umbilical cerebral-carotid, or cerebral-aortic ratios (Sensitivity 85% specificity 90%). When used as predictor of poor perinatal outcome in growth retarded fetuses, the cerebral umbilical ratio shows a sensitivity of 90% compared with 78% of the middle cerebral artery, and 83% for the umbilical artery indices. Changes of this ratio are well correlated with the fetal pO2 changes. The renal flow response to hypoxia depends on the degree of hypoxia. Opposite responses were found in case of moderate, and severe IUGR or hypoxia. Thus, it is too early to conclude if the renal indices are reliable parameters for the evaluation of fetal hypoxia. The sensitivity in predicting IUGR was for the aortic PI: 41% and for the aortic BFC (Blood flow classes): 57%. In predicting delivery for fetal distress, the corresponding values were 76 and 87%, respectively. Because the resistance indices are heart rate-dependent, it is dangerous to draw any conclusion from one single value of any of these parameters. Only several successive measurement of the Doppler indices or of their ratio, may lead to a reliable evaluation of fetal hemodynamics. In the case of significant IUGR with abnormal Doppler indices it is recommended to repeat the Doppler measurements daily both at the cerebral and umbilical or aortic level in order to follow up the fetal flow redistribution which is highly correlated with the fetal pO2 changes.     

Neural Network Computer Analysis of Fetal Heart Rate

> Objective: A nonsubjective evaluation of intrapartum fetal heart rate (FHR) with a neural network (NNW) computer system and its clinical application. Methods: Eight simple FHR data were input into the NNW computer after 16-step normalizations. The computer was composed of 40 units in the input layer, 30 in intermediate layer, and 3 in the output layer, and the probabilities to be normal, suspicious, and pathological were obtained at the output. Before use, the computer was trained 10,000 times by 50-min teacher FHR data of 20 cases with known outcomes. The trained NNW computer was tested by FHRs of another 29 cases. The outcome probabilities in 15 min were calculated every 5 min in another 10 cases, and the bar graphs of the probabilities were displayed in sequence in the trendgrams. Results: The trained NNW computer was 100% accurate in the internal check; in the external check 86% of the results were evaluated correctly with the cardiotocogram, Apgar score, and umbilical arterial pH of the 29 test cases. The FHR scores of our conventional computer FHR analysis were higher in the suspicious and pathological groups than the normal group, and the fetal distress index was high in the pathological group. The trendgrams were simply accurate in typically normal or abnormal cases, transitory abnormal probabilities were shown in intermediate cases, and mixed suspicious and pathological probabilities suggested pathological outcome. Conclusions: The outcome probabilities and their trendgrams in the NNW FHR analysis are promising in objective decision making in the intrapartum stage.     

Discriminant analysis of the Ullrich-Turner syndrome neurocognitive profile

OBJECTIVES: To evaluate the effect of fetal behavioral states on the relationship between fetal heart rate (FHR) and middle cerebral artery resistance index (MCA RI) in normal fetuses. METHODS: The FHR and MCA RI of 10 normal cases from 37 to 40 weeks of gestation were recorded consecutively over a 45-min period. Correlations between the MCA RI and FHR during resting and active phases, classified by an actocardiotocogram, were analyzed by simple regression analysis. RESULTS: The mean FHR and MCA RI were significantly higher during the active phase (140.3 +/- 6.6 bpm, 0.79 +/- 0.06) than those during the resting phase (137.4 +/- 6.8 bpm, 0.75 +/- 0.07, P < 0.01, two sample t-test). There was a significant negative correlation (r = - 0.22, n = 2642, P < 0.01) between RI and FHR during the active phase and a significant positive correlation (r = 0.28, n = 2066, P < 0.001) during the resting phase. CONCLUSIONS: The relationship between FHR and the MCA RI during the resting phase is different from during the active phase.     

Fetal response to voluntary maternal hyperventilation. A preliminary report

Maternal hyperventilation can cause transient reduction in fetal oxygen tension. Fifty women with normal and high-risk pregnancies, between the 32nd and 43rd week, were voluntarily hyperventilated; in 33, fetal heart rate (FHR) acceleration or transient tachycardia were observed (reactive FHR). Of the 33 pregnancies the outcome was good in 30 (91%) as judged by the absence of perinatal death, no fetal distress in labor and no intrauterine growth retardation (IUGR). In 14 patients in whom there was no FHR response to maternal hyperventilation (non-reactive FHR), the outcome of pregnancy was significantly worse; one infant died neonatally, 10 were either chronically (IUGR), or acutely distressed. Only in 3 was the outcome good (21%). The study showed that there is good correlation between a "reactive" FHR and favorable neonatal outcome, and between a "non-reactive" FHR and an unfavorable neonatal outcome.     

Neuronal responses in monkey anterior putamen during operant bar-press behavior

OBJECTIVE: To determine whether computer assisted fetal heart rate analysis or the biophysical profile score can provide noninvasive prediction of fetal acidaemia. DESIGN: Cross sectional study. SETTING: Harris Birthright Research Centre for Fetal Medicine, King's College Hospital School of Medicine, London. SUBJECTS: Forty-one women with pregnancies complicated by diabetes mellitus. INTERVENTIONS: Fetal heart rate (FHR) monitoring with computer assisted analysis, biophysical profile score (BPS) and cordocentesis for measurement of umbilical venous blood glucose concentration and blood gases, up to 24 h before delivery at 27 to 39 weeks gestation. RESULTS: The mean umbilical venous blood pH was significantly lower than the normal mean for gestation, and was below the 5th centile in 18 pregnancies, including all six cases where the mother had nephropathy and hypertension. The mean pO2 was not significantly different from the normal mean for gestation. There were significant associations between fetal acidaemia and both the BPS (r = 0.46, P < 0.01) and FHR variation (r = 0.42, P < 0.01). However, of the 12 acidaemic fetuses of non-nephropathic mothers, nine had normal BPS and six had normal FHR variation. CONCLUSIONS: In pregnancies complicated by maternal diabetes mellitus, BPS and FHR variation are of limited value in the prediction of fetal blood pH.     

Sampling in social gerontology: a method of locating specialized populations

This study reviews 27 patients with positive OCTs who were subsequently allowed a trial of directly monitored labor. Of these, 19 patients (70%) developed FHR signs of fetal distress and 8 (30%) tolerated labor without late decelerations. These patients were evaluated for signs of fetal reactivity (acceleration of the FHR associated with fetal movement of contractions) during the OCT. Those with a reactive pattern during the OCT (15 patients) uniformly had a good fetal outcome (unless there was birth trauma or premature delivery), but 8 of these 15 patients showed fetal distress during monitored labor. If the positive OCT was associated with a nonreactive baseline FHR recording, a trial of labor uniformly resulted in FHR signs of fetal distress. It is therefore concluded that a patient with a nonreactive positive OCT is unlikely to tolerate subsequent labor without fetal distress.     

Plasma exchange in myasthenia gravis

OBJECTIVE: To evaluate whether fetal heart rate (FHR) patterns obtained in nonstress testing within 24 hours of delivery in patients with preterm delivery were associated with histologic acute infection, and if so, whether the associations are with maternal as opposed to fetal acute inflammation (acute amnionitis versus acute umbilical vasculitis). METHODS: The data set included 351 consecutive patients delivering from 22 to 32 weeks' gestation (excluding cases of preeclampsia; nonhypertensive abruption; stillbirth; fetal structural and karyotypic anomalies; Rh isoimmunization and hydrops fetalis; and maternal diabetes and hypertension). Severe variable decelerations were defined as FHR < 70 beats per minute lasting > 60 seconds, and decreased fetal heart variability included both reduced beat-to-beat variability and long-term heart rate cyclicity. Amniotic fluid volume was graded sonographically as part of a fetal biophysical profile. Acute inflammation of amnion (indicative of maternal inflammation) and umbilical cord (fetal inflammation) were scored by a single pathologist blinded to clinical data. RESULTS: Severe FHR variable decelerations were directly related to acute amnionitis (P = .012) and acute umbilical vasculitis (P = .0013). In preterm labor, decreased FHR variability was related to acute amnionitis (P = .005). All observations were independent of amniotic fluid volume or use of tocolytic agents. CONCLUSIONS: Severe variable decelerations and decreased FHR variability at < 32 weeks' gestation are related to histologic evidence of acute inflammation.     

The spread of methicillin-resistant Staphylococcus aureus in a rural community: will it become a common microorganism colonizing among the general population?

Myocardial perfusion imaging with 99mTc-MIBI was studied in 80 patients with coronary artery disease (CAD), 29 cases of normal controls and 37 cases of noncoronary heart diseases. The perfusion imaging was analysed both by qualitative and quantitative methods. The results revealed that the diagnostic sensitivity, specificity and accuracy for CAD were 91.5%, 83.8%, and 88.5% respectively by qualitativ method, and were 88.1%, 94.6% and 90.6% respectively by quantitative method. The diagnostic sensitivity of electrocardiogram (ECG) was 69.5%. Fourteen cases with the narrowing of coronary artery > 50% shown by coronary angiography also had abnormal myocardial perfusion imaging. It suggests that analysis of perfusion imaging by quantitative method in detecting CAD is superior than qualitative method and ECG.     

Does the onset of neonatal seizures correlate with the timing of fetal neurologic injury?

The onset of seizures after birth has been considered evidence of an intrapartum asphyxial event. The present study was undertaken to determine whether the timing of neonatal seizures after birth correlated with the timing of a fetal asphyxial event. Thus, singleton term infants diagnosed with hypoxic ischemic encephalopathy and permanent brain injury had a mean birth to seizure onset interval of 9.8 +/- 17.7 (range 1-90) hours. When these infants were categorized according to their fetal heart rate (FHR) patterns, the acute group (normal FHR followed by a sudden prolonged FHR deceleration that continued until delivery) tended to have earlier seizures than infants did within the tachycardia group (normal FHR followed by tachycardia, repetitive decelerations, and diminished variability) and the preadmission group (persistent nonreactive FHR pattern intrapartum). These seizure intervals were as follows: acute, 6.6 +/- 18.0 (range 1-90) hours; tachycardia, 11.1 +/- 17.1 (range 1-61) hours; and preadmission, 11.8 +/- 17.9 (range 1-79) hours (p < 0.05). But the range varied widely and no group was categorically distinct. In conclusion, the onset of neonatal seizures after birth does not, in and of itself, appear to be a reliable indicator of the timing of fetal neurologic injury.     

Multicenter study on the clinical value of fetal pulse oximetry. II. Compared predictive values of pulse oximetry and fetal blood analysis. The French Study Group on Fetal Pulse Oximetry

OBJECTIVE: Our purpose was to compare the predictive value of intrapartum fetal pulse oximetry with that of fetal blood analysis for an abnormal neonatal outcome in case of an abnormal fetal heart rate. STUDY DESIGN: A prospective multicenter observational study was conducted from June 1994 to November 1995. Fetal oxygen saturation was continuously recorded with a Nellcor N-400 fetal pulse oximeter in case of an abnormal fetal heart rate during labor. Simultaneous readings of fetal oxygen saturation and fetal blood analysis obtained before birth (i.e., either at full dilatation or before cesarean section when indicated) were compared with the neonatal status. The criteria for an abnormal neonatal outcome were (1) an umbilical arterial blood pH < or = 7.15 and (2) a combined variable including 5-minute Apgar score < or = 7, umbilical arterial pH < or = 7.15, secondary respiratory distress, transfer in a neonatal care unit, or neonatal death. RESULTS: At a 7.20 threshold for fetal scalp pH and 30% for fetal oxygen saturation (i.e., the 10th percentile in the study population), the predictive value of fetal pulse oximetry was similar to that of fetal blood analysis for an arterial umbilical pH < or = 7.15 and for an abnormal neonatal outcome (positive predictive value 56% vs 55%, negative predictive value 81% vs 82%, sensitivity 29% vs 35%, and specificity 93% vs 91%, respectively). The receiver-operator characteristic curve showed similar performance of either technique for cutoff values < or = 7.20 for fetal blood pH and < or = 30% for fetal oxygen saturation, whereas fetal pulse oximetry became superior at higher thresholds. CONCLUSION: The predictive value of intrapartum fetal pulse oximetry can be favorably compared with that of fetal blood analysis. Randomized controlled management trials can now be performed to assess potential clinical benefits of this new tool.     

Premenstrual dysphoric disorder: controversies surrounding the diagnosis

OBJECTIVE: To evaluate the umbilical and uterine arterial Doppler flow velocity waveform systolic to diastolic (S/D) ratios performed at 24-30 weeks gestation for predicting fetal growth retardation (IUGR). METHODS: A prospective double blind study was conducted in 118 cases of high risk singleton pregnant women. The umbilical and uterine arterial S/D ratios were measured at 24-30 gestational weeks and the pregnancy outcomes were followed up. RESULTS: The prevalence of IUGR in our study population was 16.9%. At 24-30 weeks gestation, the S/D ratio of both umbilical artery and uterine artery in IUGR pregnant women were significantly higher than those in normal pregnant women, while the fetal biometric measurements were normal in all the 118 cases. The sensitivity, specificity and positive predictive value of umbilical arterial S/D ratio to predict IUGR were 80.0%, 83.7% and 50.0% with a Kappa index of 0.51 at 24-30 weeks gestation. With lower sensitivity, specificity, positive predictive value and Kappa index (40.0%, 84.5%, 34.8% and 0.23 respectively), the uterine arterial S/D ratio had less predictive value. CONCLUSIONS: The umbilical arterial Doppler flow velocity waveform S/D ratio may be an earlier predictor for screening of IUGR at 24-30 weeks gestation in high risk pregnant women with normal fetal biometric measurements.     

Clinical and ultrasonographic features of dextroposition of the fetal heart

OBJECTIVE: Our purpose was to characterize the findings associated with dextroposition of the fetal heart. STUDY DESIGN: A fetal echocardiography database was retrospectively searched from January 1990 through December 1996 to identify all cases referred or diagnosed with dextroposition of the fetal heart. Dextroposition was defined as most of the normally connected fetal heart found on the right side of the fetal chest. Intracardiac and extracardiac fetal anomalies were reviewed. All available karyotypes and postnatal examinations were reviewed. RESULTS: During the study period 2882 fetal echocardiograms were performed, of which 297 (10.3%) were abnormal. Of these, 14 had dextroposition. Associated anomalies included atrioventricular canal (29%), diaphragmatic hernia (21%), and aneuploidy (14%). Isolated dextroposition with no other significant anomalies was seen in only 1 case. In another, no anomalies were noted except for suspected agenesis of 1 lobe of the right lung; karyotype and postnatal evaluation revealed no other abnormalities in both cases. CONCLUSIONS: Dextroposition of the fetal heart was seen in 0.5% of our fetal echocardiograms and was associated with significant anomalies in 86% of our cases. When diagnosed, a targeted ultrasonogram, fetal echocardiogram, and karyotype should be offered.     

The early and late effects of surgical closure of ventricular septal defects on pulmonary vascular dynamics

In sixty patients who underwent closure of ventricular septal defect (VSD), cardiac catheterizations were performed before and late after surgery together with pressure measurements immediately after closure of the VSD during surgery. Pulmonary arterial mean pressure (PAm), pulmonary arterial systolic pressure to systemic arterial systolic pressure ratio (Pp/Ps), and pulmonary vascular resistance to systemic vascular resistance ratio (Rp/Rs) were measured and calculated. The patients were classified into 5 groups according to the preoperative Rp/Rs and Qp/Qs as was reported by Nakada: Group A: Rp/Rs less than 0.15, Qp/Qs larger than or equal to 1.8, Group B: Rp/Rs less than 0.15, Qp/Qs less than 1.8, Group C: 0.15 less than or equal to Rp/Rs less than 0.50, Group D: 0.50 less than or equal to Rp/Rs less than 0.85, Group E: 0.85 less than or equal to Rp/Rs. These groups were further divided into 3 groups respectively according to age at operation (less than or equal to 2 years, 3 or 4 years, 5 years less than or equal to). The averages of PAm, Pp/Ps, and Rp/Rs were within the normal range in Group A and B patients (normal pulmonary vascular resistance groups) irrespective to the age at operation except the average of PAm before surgery. In Group C, D and E patients (elevated pulmonary vascular resistance group), these variables decreased immediately after closure of VSD, and further decreases were noted at the time of late catheterization. These variables, however, did not completely normalize even at that time. Among the patients operated upon at 2 years of age or less, the averages of these variables normalized immediately after closure of the VSD. When operated upon at 3 or 4 years of age, these variables decreased but did not normalize immediately after closure of the VSD and were found to be within the normal range at the time of late catheterization. When operated upon at 5 years of age or more, these variables decreased immediately after closure of the VSD, and further decrease was found at the time of late catheterization but mostly remained in the abnormal range even at this time. From the data obtained herein, the factors producing the pulmonary vascular resistances in respective age groups were discussed. The closure of VSD in patients with elevated pulmonary vascular resistance is recommended at the latest 4 years of age and preferably at 2 years of age or less, in order to obtain normal pulmonary circulatory dynamics after surgery.     

Fetal heart rate characteristics at 25 to 28 weeks' gestation

The objective of this article is to define normative fetal heart rate (FHR) tracing characteristics between 25-28 weeks' gestation in a low-risk population with normal pregnancy outcomes and to determine which criteria best determine FHR reactivity. Continuous FHR tracings were reviewed from 188 low-risk women participating in a trial of the Mammary Stimulation Test (MST) at 25-28 weeks' gestation. A reactive tracing required the presence of > or =two accelerations in 20 min. Different acceleration criteria were evaluated based upon the width of the acceleration (short vs. long) and the amplitude of the acceleration (10 vs. 15 bpm). Seventy-one percent of the FHR tracings were reactive using the higher amplitude (15 bpm), short criteria. This number increased significantly to 92% when the lower amplitude (10 bpm), short criteria were used (p <0.01). As gestational age advanced, there was a trend toward increased reactivity irrespective of which criteria were used, but these differences were not significant. Reducing the acceleration amplitude criteria to 10 bpm in preterm pregnancies will maximize the number of reactive nonstress tests. This is advantageous because it would improve test specificity and decrease the false-positive rate. Our findings need to be prospectively validated in a high-risk population.     

The use of second-trimester genetic sonogram in guiding clinical management of patients at increased risk for fetal trisomy 21

OBJECTIVE: To test the efficacy of ultrasound in detecting fetuses with trisomy 21. METHODS: From November 1, 1992, to December 31, 1995, a second-trimester genetic sonogram was offered to all women with singleton fetuses at increased risk (at least 1:274) for trisomy 21, who had either declined genetic amniocentesis or chose to have a sonogram before deciding whether to undergo an amniocentesis. In addition to standard fetal biometry, the following ultrasound markers for aneuploidy were evaluated: structural anomalies (including face, hands, and cardiac [four-chamber view and outflow tracts]), short femur, short humerus, pyelectasis, nuchal fold thickening, echogenic bowel, choroid plexus cysts, hypoplastic middle phalanx of the fifth digit, wide space between the first and second toes, and two-vessel umbilical cord. Outcome information included the results of genetic amniocentesis, if performed, or the results of postnatal pediatric assessment and follow-up. RESULTS: Five hundred seventy-three patients had a genetic sonogram between 15 and 23 weeks' gestation: 378 patients had advanced maternal age (at least 35 years), 141 had abnormal serum biochemistry, and 54 had both. The majority (495, or 86.3%) had a normal genetic sonogram (absence of abnormal ultrasound markers); 51 (9%) had one marker present, and 27 (4.7%) had two or more markers present. Outcome was obtained on 422 patients (the remaining were ongoing pregnancies or were lost to follow-up). Twelve of 14 fetuses with trisomy 21, one fetus with trisomy 13, and one fetus with triploidy had two or more abnormal ultrasound markers present; one fetus with trisomy 21 had one abnormal marker and one had a completely normal ultrasound. When one or more abnormal ultrasound markers were present, the sensitivity, specificity, and positive and negative predictive values for trisomy 21 were 92.8%, 86.7%, 19.4%, and 99.7%, respectively. When two or more abnormal ultrasound markers were present, the corresponding values were 85.7%, 96.8%, 48%, and 99.5%. In the study population, the amniocentesis rate was 12.7% overall and 17.3% in cases with known outcome. CONCLUSION: Second-trimester genetic sonogram may be a reasonable alternative for patients at increased risk for fetal trisomy 21 who wish to avoid amniocentesis. In experienced hands, this approach may result in a high detection rate of trisomy 21 (93%), with an amniocentesis rate of less than 20%.     

Etiology and outcome of acute renal failure in elderly patients

OBJECTIVE: To test the usefulness of the fetal transverse cerebellar diameter/abdominal circumference (TCD/AC) ratio in predicting known small-for-gestational-age (SGA) infants. METHOD: The relationship between fetal TCD and AC throughout the second half of pregnancy was investigated in 635 well-dated, normal pregnancies and examined with regard to gestational age and infant birth weight percentiles. RESULTS: One hundred eighteen (19%) fetuses were excluded due to inadequate visualization of the fetal cerebellum. A strong correlation was noted between gestational age determined by the last menstrual period and both fetal TCD (r2 = 0.91338) and AC (r2 = 0.89361) in fetuses with birth weights between the 10th and 90th percentiles (n = 407; mean 14.4, S.D. 1.2). Although the TCD/AC ratio showed a poor correlation with gestational age (r2 = 0.15788), a slight increase was noted during gestation. A TCD/AC ratio greater than 15.5 was present in 80% of SGA infants when measurements were performed within 1 week of delivery. CONCLUSION: Fetal TCD/AC ratio as a gestational age-independent method could improve diagnostic sensitivity and specificity in the early detection of fetal growth abnormalities.     

Barriers to effective psychiatric emergency services for elderly persons

OBJECTIVE: To evaluate the etiology and outcome of fetal hydrops of nonimmune origin diagnosed in utero during the first half of pregnancy. METHODS: We reviewed 45 cases of nonimmune fetal hydrops presenting between 11 and 17 weeks' gestation over a 4-year period. RESULTS: The median gestational age at diagnosis of fetal hydrops was 14 weeks. Placental edema was most commonly associated with generalized skin edema. Ascites was also observed in four cases, but no case presented with pleural or pericardial effusion. The fetal karyotype was abnormal in 35 cases (77.8%). Of the ten fetuses with a normal karyotype, four were classified as idiopathic, three had isolated atrioventricular septal defect, two were associated with maternal infection, and one had multiple pterygium. Fetal heart rate anomalies were found in both chromosomally normal and abnormal fetuses. All but one of the karyotypically abnormal pregnancies and five of ten euploid pregnancies were terminated. In all six pregnancies that continued, resolution occurred before mid-gestation. Three continuing euploid pregnancies resulted in fetal death, and only two had a normal outcome. CONCLUSION: Nonimmune fetal hydrops diagnosed before 18 weeks' gestation is associated with a higher incidence of aneuploidy than hydrops diagnosed during the second half of pregnancy. In most affected fetuses with a normal karyotype, spontaneous resolution occurred before 24 weeks' gestation, although the outcome was generally unfavorable.     

Fetal cardiac responding: Maturational and behavioral correlates.

Intrapartum fetal heart rate (FHR) patterns in 48 full-term or preterm infants were classified as acceleratory or deceleratory. Deceleratory patterns were associated with higher baseline HR, lower birth weight, prematurity, and more abnormal reflexes scored on the Newborn Behavior Assessment Scale. Results suggest that FHR responses in the clinically healthy newborn may be related to early stress tolerance and CNS integrity. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fetal RhD typing by polymerase chain reaction in pregnancies complicated by rhesus alloimmunization

OBJECTIVE: To review the specificity and sensitivity of diagnostic techniques using the polymerase chain reaction (PCR) on amniotic fluid (AF) samples for the determination of fetal RhD status. DATA SOURCES: A MEDLINE computerized search was conducted for January 1991 through March 1996 using the key terms "polymerase chain reaction," "rhesus," and "RhD typing." METHODS OF STUDY SELECTION: All articles describing the use of PCR in AF for RhD typing were reviewed. Only cases in which the results of PCR testing were confirmed by fetal or neonatal serology were included in the final analysis. TABULATION, INTEGRATION, AND RESULTS: The results of PCR typing were compared with serology to determine the sensitivity, specificity, and positive and negative predictive values of DNA-based techniques. A total of 500 cases were reviewed, in which four different sets of oligonucleotide primers were used. The sensitivity and specificity of PCR typing were 98.7% and 100%, respectively, and the positive and negative predictive values were 100% and 96.9%, respectively. In five cases, an RhD-positive fetus was incorrectly diagnosed: Two fetuses died, one neonate needed exchange transfusions, and another neonate needed phototherapy in conjunction with a simple transfusion. The remaining infant was lost to follow-up. A theoretical model indicated that amniocentesis with PCR-based techniques for fetal RhD typing would be associated with a fourfold reduction in perinatal loss compared with funipuncture and serology for fetal typing. CONCLUSIONS: This lower rate of procedure-related loss makes RhD typing using AF the preferred method for assessing the fetal Rh status in cases of a heterozygous paternal genotype.     

Serum neuron-specific enolase as early predictor of outcome after cardiac arrest

OBJECTIVE: To examine the prognostic value of serum neuron-specific enolase for early prediction of outcome in patients at risk for anoxic encephalopathy after cardiac arrest. DESIGN: Prospective study. SETTING: Coronary intensive care unit of the University of Heidelberg. PATIENTS: Forty-three patients (66.8 +/- 12.7 [SD] yrs, range 33 to 85) who had had either primary or secondary cardiac arrest, followed by cardiopulmonary resuscitation (CPR). INTERVENTIONS: Serial blood samples and clinical examinations. MEASUREMENTS AND MAIN RESULTS: Serum neuron-specific enolase concentrations were determined after CPR on 7 consecutive days. Twenty-five patients remained comatose and subsequently died; 18 patients survived the first 3 months and had no relevant functional deficit at 3-month follow-up. Neuron-specific enolase concentrations were correlated with neurologic outcome. Concentrations of >33 ng/mL predicted persistent coma with a high specificity (100%) and a positive predictive value of 100%. Overall sensitivity was 80%, with a negative predictive value of 78%. Serum concentrations of neuron-specific enolase exceeded this cutoff value no more than 3 days after cardiac arrest in 95% of patients in whom these concentrations had exceeded 33 ng/mL. CONCLUSIONS: In patients who have been resuscitated after cardiac arrest, serum neuron-specific enolase concentrations of >33 ng/mL predict persistent coma with a high specificity. Values below this cutoff level do not necessarily indicate complete recovery, because this method has a sensitivity of 80%.