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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↗
PubMed1995

Biophysical profile testing as an indicator of fetal well-being in high-order multiple gestations.

OBJECTIVE: The purpose of this investigation was to determine the value of biophysical profile testing in preventing intrapartum death in patients with high-order multiple gestations (triplets or quadruplets). STUDY DESIGN: A retrospective review was performed of patients with triplets and quadruplets cared for by Phoenix Perinatal Associates from October 1988 to December 1991. Biophysical profile testing was used as the primary method of fetal surveillance in these pregnancies. Fetal heart rate monitoring on an external monitor was used as back-up and in cases sent to labor and delivery for problems. The ultrasonographic parameters of the biophysical profile score were used without the nonstress test component because of technical difficulty with that test in high-order multiple pregnancies. A score of 6 to 8/8 was therefore considered reassuring, 4/8 equivocal, and 0 or 2/8 possibly abnormal. Testing was done twice per week. RESULTS: Eighteen patients with triplets and six patients with quadruplets constituted the study group. The last biophysical profile before delivery was examined to evaluate the value of the test. There were no antepartum deaths in these 78 babies. The last biophysical profile score was 2/8 in nine fetuses of five triplet pregnancies and two fetuses of one quadruplet pregnancy. These six pregnancies (25%) were delivered on the basis of biophysical profile results and clinical circumstances. There was no morbidity or mortality in the 19 babies delivered because of abnormal biophysical profile testing. Four pregnancies had poor outcome at delivery in spite of 8/8 biophysical profile scores on all babies within 4 days of delivery. Of these four, two patients had worsening pregnancy-induced hypertension, one had abruptio placentae, and one had a severely growth-retarded infant. CONCLUSION: There were no stillbirths in this series. Twenty-five percent of these pregnancies eventually were delivered for nonreassuring biophysical profile testing, with good outcome. Four pregnancies had poor neonatal outcome in spite of normal biophysical profile testing. All of these pregnancies had active changes in physiologic features leading to delivery (two worsening pregnancy-induced hypertension, one abruptio placentae, one spontaneous rupture of membranes and labor). The biophysical profile appears to be a reliable antepartum test of fetal well-being in triplets and quadruplets.

Female↗
PubMed1994

Perinatal outcome with the modified biophysical profile.

OBJECTIVE: Our purpose was to evaluate perinatal outcomes in high-risk pregnancies monitored with a modified biophysical profile. STUDY DESIGN: All non-insulin-dependent patients referred for antepartum fetal surveillance received a modified biophysical profile biweekly. A modified biophysical profile is a combination of a nonstress test and an amniotic fluid index. Patients with a singleton gestation and intact membranes were entered into a protocol of randomized backup testing for an abnormal modified biophysical profile. Those patients having a nonreactive fetal heart rate, significant variable decelerations, late decelerations, or an amniotic fluid index < or = 5.0 cm received either a contraction stress test or a biophysical profile immediately. Once randomized, a patient received the same backup test, when indicated, with subsequent testing. RESULTS: A total of 2774 patients had 17,429 tests with an uncorrected perinatal mortality rate of 2.9 per 1000. The overall incidence of an adverse perinatal outcome (i.e., perinatal death or nursery death before infant hospital discharge, cesarean delivery for fetal distress within the first 2 hours of labor, 5-minute Apgar score < 7, neonatal seizures or grade III or IV central nervous system hemorrhage) was 7.0%. When compared with patients having persistently normal modified biophysical profile, patients requiring a backup test had a significantly greater incidence of adverse perinatal outcome (9.3% vs 4.9%, p < 0.001, odds ratio 2.0, 95% confidence interval 1.5 to 2.7) and small-for-gestational-age infants (5.2% vs 2.4%, p < 0.001, odds ratio 2.2, 95% confidence interval 1.5 to 3.5). No differences in outcomes between patients randomized to a contraction stress test versus a biophysical profile could be identified either overall or in limiting the analysis to outcome after a negative last test. However, patients having contraction stress test as a backup test had a significantly higher rate of intervention for an abnormal test result than did those having a biophysical profile backup test (23.7% vs 16.6%, p < 0.002, odds ratio 1.6, 95% confidence interval 1.2 to 2.1). CONCLUSION: The modified biophysical profile is an excellent means of fetal surveillance and identifies a group of patients at increased risk for adverse perinatal outcome and small-for-gestational-age infants. There does not appear to be a significant benefit with the contraction stress test compared with the biophysical profile as a backup test. Further, the contraction stress test is associated with a higher rate of intervention for an abnormal test than is the biophysical profile.

Adult↗
PubMed1991

The relationships among umbilical artery velocimetry, fetal biophysical profile, and placental inflammation in preterm premature rupture of the membranes.

The relationships among umbilical artery velocimetry, fetal biophysical profile, and placental inflammation in 44 consecutive patients with preterm premature rupture of the membranes were determined. All patients were followed up with daily fetal biophysical profiles and systolic/diastolic ratios. After delivery, placental pathologic examination for histologic evidence of infection (umbilical vasculitis) was performed in all cases according to a standard protocol. The longitudinal trends of fetal biophysical profile scores and systolic/diastolic ratios were analyzed for patients with and without umbilical vasculitis. Analysis of the longitudinal trend during the period of 2 to 7 days before delivery showed that there were no differences of biophysical scores of systolic/diastolic ratios in either group. However, in the last examination, within 24 hours of delivery, patients with umbilical vasculitis had higher systolic/diastolic ratios and lower biophysical profile scores as compared with previous examinations. In addition, the biophysical profile score of the last examination 24 hours before delivery in patients with umbilical vasculitis was found to be significantly lower as compared with patients without umbilical vasculitis (mean +/- SD, 6.6 +/- 2.3 versus 8.2 +/- 2.4, respectively). These data suggest that subclinical stages of infection are associated with biophysical alterations of the fetoplacental unit (i.e., simultaneous decrease in fetal biophysical activities and increase in systolic/diastolic ratios). Daily umbilical artery systolic/diastolic ratios, in conjunction with biophysical profiles, may be useful to follow up patients with preterm premature rupture of the membranes.

Blood Flow Velocity↗
PubMed1994

Effect of intravenous magnesium sulfate on the biophysical profile of the healthy preterm fetus.

OBJECTIVE: The null hypothesis is that intravenous magnesium sulfate does not affect the biophysical profile of the healthy preterm fetus. STUDY DESIGN: Thirty-one fetuses of 25 patients between the gestational ages of 24 and 35 weeks, median 31.4 and mean (+/- SD) 30.4 (+/- 2.9), who required tocolysis for uterine contractions were prospectively studied. After normal fetal biophysical assessment was documented, intravenous magnesium sulfate was started as a 4 or 6 gm loading dose and then infused at 2 to 3.5 gm/hr to achieve tocolysis. Blood was drawn for measurement of maternal serum magnesium levels immediately before intravenous magnesium sulfate was administered and at 2 and 12 hours after the loading dose. Biophysical profiles, consisting of a possible 12 points, were performed at the same time as blood was drawn. Serum magnesium levels were compared with one-way analysis of variance for repeated measures and biophysical profile scores with Friedman's test. Statistical significance was considered p < 0.05. RESULTS: Mean (+/- SD) serum magnesium levels were 1.7 (+/- 0.1) mg/dl before infusion, 4.3 (+/- 0.6) mg/dl at 2 hours, and 5.2 (+/- 0.7) mg/dl at 12 hours (p < 0.001). Six fetuses did not have a 12-hour biophysical profile; three were delivered for severe variable decelerations, two progressed in labor, and in one tocolysis was discontinued. The median biophysical profile score was 11 before intravenous magnesium sulfate, at 2 hours, and at 12 hours after the loading dose. The biophysical parameters present and the percentage of fetuses with each parameter were as follows: breathing (> 30 seconds), 88% (22/25) before magnesium sulfate, 84% (21/25) at 2 hours, and 92% (23/25) at 12 hours; nonstress test (reactive), 84% (21/25) before magnesium sulfate, 68% (17/25) at 2 hours, and 80% (20/25) at 12 hours; movement (normal), 100% (25/25) before magnesium sulfate, 100% (25/25) at 2 hours, and 96% (24/25) at 12 hours. CONCLUSION: Intravenous magnesium sulfate did not significantly alter the biophysical profile in the 25 fetuses evaluated by three biophysical profiles in spite of the significant increase in maternal serum magnesium levels.

Adult↗
PubMed1993

Fetal biophysical profile score. VI. Correlation with antepartum umbilical venous fetal pH.

OBJECTIVE: Our objective was to determine the relationship, if any, between the fetal biophysical profile score and antepartum umbilical venous pH. STUDY DESIGN: This was a prospective observational study conducted concurrently in two centers and involving two discrete high-risk groups of fetuses. Fetal biophysical profile scores were compared with umbilical venous pH values measured in blood obtained by immediate cordocentesis. A total of 493 paired observations of biophysical profile score and pH were made; 104 observations were of fetuses with intrauterine growth retardation and 389 observations were of fetuses with alloimmune anemia. RESULTS: In both data sets there was a highly significant linear correlation between biophysical profile score and umbilical venous pH. Poor biophysical profile score performance (a score of 0 of 10) was always associated with a pH < 7.20, whereas the pH was always > 7.20 when the biophysical profile score was 10 of 10. Sequenced sensitivity of short-term biophysical variables in the detection of acidemia was observed. CONCLUSION: The fetal biophysical profile score accurately predicts antepartum umbilical venous pH.

Analysis of Variance↗
PubMed1999

A randomized clinical trial of daily nonstress testing versus biophysical profile in the management of preterm premature rupture of membranes.

OBJECTIVE: Our purpose was to evaluate the ability of 2 different antepartum testing modalities to predict infectious morbidity in patients with preterm premature rupture of membranes. STUDY DESIGN: During a 36-month period, patients with preterm premature rupture of membranes (at 23 to 34 weeks of gestation) were randomly assigned to either a daily nonstress test or a biophysical profile, after a 24-hour observational period. We used the original scoring system of Manning et al for the biophysical profile, with a score of </=6 considered abnormal. Nonstress test results were considered abnormal if the test was nonreactive or if the patient had late decelerations or significant variable decelerations; abnormal results led to further evaluation with a biophysical profile. Results of the last test before delivery were evaluated to determine whether infectious complications had been predicted. RESULTS: One hundred thirty-five patients were enrolled in the study. Demographics, pregnancy characteristics, and neonatal outcomes were similar. Neither the daily nonstress test nor the daily biophysical profile had good sensitivity for predicting infectious complications (39.1% and 25.0%, respectively). However, both had good specificity (84.6% and 92.6%, respectively). Positive and negative predictive values were 52.9% and 75.9%, respectively, for the daily nonstress test and 66.7% and 68.4%, respectively, for the daily biophysical profile. Cost was significantly higher in the daily biophysical profile group. Nonstress testing of patients at <28 weeks' gestation generally required a backup biophysical profile. CONCLUSION: Neither the daily nonstress test nor the daily biophysical profile had good sensitivity for predicting infectious complications after preterm premature rupture of membranes.

Adult↗
PubMed1992

Biophysical profile as a predictor of amniotic fluid culture results.

The biophysical profile has been proposed as a noninvasive method of detecting fetal infection in patients with preterm premature rupture of membranes (PROM). The purpose of this study was to evaluate the biophysical profile as a rapid predictor of amniotic fluid (AF) culture results in women with PROM. Amniocentesis was performed on 111 patients with PROM at or before 34 weeks' estimated gestational age. Aerobic, anaerobic, Ureaplasma, and Mycoplasma cultures were performed on the AF. A biophysical profile was performed just before the amniocentesis. Women with positive AF cultures had a significantly lower total biophysical profile score, as well as significantly lower scores for nonstress test, fetal breathing movements, fetal movements, and AF volume, than those with negative AF cultures. However, neither the total biophysical profile score nor any of the individual components had sufficient sensitivity, specificity, or positive or negative predictive value to be useful clinically in predicting culture results. Although the incidence of positive AF cultures was inversely related to the biophysical profile score, 48% of patients with a score of 8 and 27% of those with a score of 10 had positive AF cultures. The results of this study do not support use of the biophysical profile as an early predictor of AF culture results in patients with PROM.

Amniotic Fluid↗
PubMed1991

The relationship between fetal biophysical assessment, umbilical artery velocimetry, and fetal acidosis.

In a prospective study of 62 patients undergoing cesarean delivery before the onset of labor, fetal biophysical assessment and umbilical artery systolic-diastolic ratios (S/Ds) were performed within 3 hours of delivery. There was a significant relationship between the fetal biophysical profile score and cord arterial as well as cord venous pH. However, there was no identifiable relationship between S/D and cord arterial or venous pH. The efficacies of the biophysical components alone (nonstress test [NST] and fetal biophysical profile) and in combination with S/D to predict fetal acidosis were determined. The NST had the best sensitivity (100%) and negative predictive value (100%). The fetal biophysical profile had the best specificity (91%), positive predictive value (62%), and overall efficiency (90%). The S/D had the lowest sensitivity (66%), specificity (42%), positive predictive value (16%), negative predictive value (88%), and overall efficiency (45%). The addition of S/D to the NST or fetal biophysical profile did not improve diagnostic accuracy. These data suggest that the NST should be used as a primary test for the antepartum detection of fetal acidosis, whereas the fetal biophysical profile is a reasonable adjunct test. The umbilical artery S/D, as determined by continuous-wave Doppler velocimetry, has no value as a primary method or an adjunct in the antepartum detection of fetal acidosis.

Acidosis↗
PubMed1993

Relationship between the fetal biophysical profile score, umbilical artery Doppler velocimetry, and fetal blood acid-base status determined by cordocentesis.

OBJECTIVE: Fetal hypoxia-acidosis is part of the terminal pathway leading to intrauterine fetal death. A central premise of antepartum surveillance is that identification and timely delivery of the hypoxic or acidotic fetus will prevent intrauterine death and decrease long-term neurologic damage. The optimal method to identify fetal hypoxia-acidosis has not been determined. We attempted to compare the performance of the biophysical profile score and umbilical artery Doppler velocimetry in the identification of fetal acidemia, hypoxemia, and hypercarbia as determined by pH and gas analysis of fetal blood obtained by cordocentesis. STUDY DESIGN: Fetal biophysical profile and umbilical artery Doppler velocimetry studies were performed before cordocentesis in 24 patients (26 to 40 weeks). Umbilical vein pH and blood gas values were determined in all cases. The pulsatility index of the umbilical artery was obtained with pulsed Doppler equipment. Receiver-operator characteristic curve analysis and stepwise multiple logistic regression were performed to examine the relationship between biophysical profile score, umbilical artery Doppler velocimetry, and acid-base status. RESULTS: The prevalence of fetal acidemia (pH 2 SD below the mean for gestational age) was 41.7% (10/24). There was a significant relationship between the change in umbilical artery pulsatility index and fetal acidemia (chi 2 = 26.6, p < 0.001) and hypercarbia (chi 2 = 22.9, p < 0.001), but not hypoxemia (chi 2 = 1.0, p > 0.1), and between the biophysical profile score and fetal acidemia (chi 2 = 11.1, p < 0.001) and hypercarbia (chi 2 = 9.0, p < 0.005), but not hypoxemia (chi 2 = 2.3, p > 0.1). Stepwise multiple logistic regression demonstrated that umbilical artery Doppler velocimetry was a better explanatory variable for acidemia and hypercarbia than the biophysical profile score. CONCLUSION: A strong relationship between the degree of fetal acidemia and hypercarbia and the results of umbilical artery Doppler velocimetry and biophysical profile was found. However, umbilical artery Doppler velocimetry was a better explanatory variable for these outcome than the biophysical profile score.

Acid-Base Equilibrium↗
PubMed1998

Fetal assessment based on fetal biophysical profile scoring. VIII. The incidence of cerebral palsy in tested and untested perinates.

OBJECTIVE: The intent of this comparative clinical study was fourfold: (1) to determine the incidence of cerebral palsy in a large obstetric population, (2) to compare the incidence of cerebral palsy in patients at high risk referred for and managed according to the fetal biophysical profile score result with the incidence among unreferred and untested patients, (3) to determine the relationship, if any, between the last fetal biophysical profile score and the incidence of cerebral palsy, and (4) to categorize cases of cerebral palsy according to the clinical parameters and the probable time and nature of the damaging insult. STUDY DESIGN: In this retrospective 5-year comparative study (1987 to 1991) the incidence of cerebral palsy was determined by analysis of International Classification of Diseases, Ninth Revision, -coded related medical services. The clinical records were then sought and reviewed in index cases and obstetric, neonatal, and postnatal clinical data were abstracted. Cross-correlation with partial registries was done to confirm completeness of capture of index cases. The population of referred high-risk patients who received serial fetal biophysical profile scoring and were managed according to test results was determined by review of a prospective computer-stored database and by review of patient log books. The population of untested patients was calculated as the residual of total cases minus tested cases. The rate of cerebral palsy for all patients and for the tested and untested population was calculated and compared. The tested and untested perinates were compared for birth age, weight, and assigned timing or etiology of cerebral palsy. In the tested population the distribution of test results by last recorded biophysical profile score was determined and the relationship between the last test result and cerebral palsy and predictive accuracy parameters of the fetal biophysical profile score were calculated. RESULTS: The incidence of cerebral palsy among the 84,947 live births was 3.68 per 1000 live births (313 cases). The rate of cerebral palsy in the 26,290 referred high-risk tested patients was 1.33 per 1000 (35 cases) compared with a rate of 4.74 per 1000 live births in the 58,657 untested mixed low-risk/high-risk patients (278 cases). These differences were highly significant. A significant declining trend in the annual incidence of cerebral palsy was observed in the total population and the untested population, whereas the rate in the tested population remained relatively constant over the 5-year study interval. The differences in the cerebral palsy rate between the tested and untested population were not related to differences in gestational age, birth weight, or assigned timing or etiology category. In the tested population the relationship between the incidence of cerebral palsy and the last test fetal biophysical profile score was inverse, exponential, and highly significant. CONCLUSIONS: Antepartum assessment by fetal biophysical profile scoring is associated with a significant reduction in the incidence of cerebral palsy compared with untested patients. The relationship between the last test score and the incidence of cerebral palsy is inverse and exponential, suggesting that antenatal asphyxia is an important and potentially avoidable cause of cerebral palsy.

Birth Weight↗
PubMed2003

The effect of glucocorticosteroid administration on fetal movements and biophysical profile scores in normal pregnancies.

OBJECTIVE: To evaluate and quantify the effect of glucocorticosteroid administration on fetal movements and biophysical profile scores. METHODS: Eighteen women at 32-34 weeks' gestation were enrolled. Inclusion criterion was an uncomplicated singleton pregnancy not considered to be at high risk. Patients participated for 3 consecutive days. On day 1, the patients underwent a baseline biophysical profile including a non-stress test followed by a 12-mg betamethasone intramuscular injection. On day 2, the patients received a non-stress test and a second dose of betamethasone. On day 3, a biophysical profile with non-stress test was performed. Maternal counts of fetal kicks were also recorded before, during and after the study period. Each test was conducted at approximately the same time of day to control for diurnal variation. Comparison was made between pre-betamethasone biophysical profile scores and fetal movement and post-betamethasone biophysical profile scores and fetal movement. RESULTS: Biophysical profile scores were reduced in 28% of the study population after betamethasone administration (p < 0.05). Amniotic fluid index on day 3 was decreased from baseline in 72% of patients after betamethasone administration (p < 0.05). Forty-four per cent of patients reported a decrease in fetal movement. Of these patients, 87% had a decreased amniotic fluid index when compared to baseline (p < 0.05). CONCLUSIONS: Fetal movements and breathing motion were decreased after glucocorticosteroid administration, as evidenced by biophysical profile scores and kick counts. The decrease in the amniotic fluid index observed after glucocorticosteroid administration may have been the result of decreased fetal breathing and, therefore, decreased efflux of alveolar fluid into the amniotic sac.

Amniotic Fluid↗
PubMed2005

Probing bacterial interactions: integrated approaches combining atomic force microscopy, electron microscopy and biophysical techniques.

Recent developments in the application of Atomic Force Microscopy (AFM) and other biophysical techniques for the study of bacterial interactions and adhesion are discussed in the light of established biological and microscopic approaches. Whereas molecular-biological techniques combined with electron microscopy allow the identification and localization of surface constituents mediating bacterial interactions, with AFM it has become possible to actually measure the forces involved in bacterial interactions. Combined with the flexibility of AFM in probing various types of physical interactions, such as electrostatic interactions, specific ligand-receptor interactions and the elastic forces of deformation and extension of bacterial surface polymers and cell wall, this provides prospects for the elucidation of the biophysical mechanism of bacterial interaction. However, because of the biochemical and a biophysical complexity of the bacterial cell wall, integrated approaches combining AFM with electron microscopy and biophysical techniques are needed to elucidate the mechanism by which a bacterium interacts with a host or material surface. The literature on electron microscopy of the bacterial cell wall is reviewed, with particular emphasis on the staining of specific classes of cell-wall constituents. The application of AFM in the analysis of bacterial surfaces is discussed, including AFM operating modes, sample preparation methods and results obtained on various strains. For various bacterial strains, the integration of EM and AFM data is discussed. Various biophysical aspects of the analysis of bacterial surface structure and interactions are discussed, including the theory of colloidal interactions and Bell's theory of cell-to-cell adhesion. An overview is given of biophysical techniques used in the analysis of the properties of bacterial surfaces and bacterial surface constituents and their integration with AFM. Finally, we discuss recent progress in the understanding of the role of bacterial interactions in medicine within the framework of the techniques and concepts discussed in the paper.

Bacteria↗
PubMed2001

The effect of steroids on the biophysical profile and Doppler indices of umbilical and middle cerebral arteries in healthy preterm fetuses.

OBJECTIVE: To examine the effect of antenatal steroids on the biophysical profile and the Doppler parameters of umbilical and middle cerebral arteries of healthy fetuses. STUDY DESIGN: Thiry-five singleton pregnancies between the gestational ages of 28 and 34 weeks, who received two consecutive doses of betamethasone 24h apart to accelerate pulmonary maturation were prospectively studied. Fetal biophysical profile and Doppler assessment were performed at 0 (pre-steroid), 24, 48, 72, 96 and 120 h after the administration of first dose. We compared the percentage of the fetuses with biophysical parameters present for each of the five components of the biophysical profile and the Doppler indices, using Cochran's Q-test, Friedman's test and one way analysis of variance of repeated measures where appropriate. The statistical significance was defined as P<0.05. RESULTS: The mean delivery time was 36.9(+/-1.8) weeks. There was a statistically significant difference in the frequency of the following findings in the pre- compared to post-steroid measurements: absence of body movements (48 h, P<0.05), non-reassuring fetal heart rate tracings (24, 48 and 72 h, P<0.05) and absence of breathing movements (24, 48 and 72 h, p<0.05). Initially none of the biophysical profile score was <or=6, whereas at 24, 48 and 72 h, 13.3, 76.7, 16.7% of them, respectively, were <or=6 (P<0.05). None of the Doppler indices was found to be affected by the steroid administration. CONCLUSION: Maternal betamethasone administration can cause a significant but transient, reduction in biophysical profile scores, however the middle cerebral and umbilical artery Doppler indices were found to be unaffected suggesting the reliability of this modality for the evaluation of the fetuses previously exposed to the antenatal steroids.

Adult↗
PubMed1992

Refining the biophysical profile with a risk-related evaluation of test performance.

OBJECTIVE: Our objective was to determine the ability of biophysical profile variables to predict bad perinatal outcome in high-risk third-trimester pregnancy. STUDY DESIGN: The outcomes of 1146 fetuses were correlated with abnormal single or multiple variables occurring in biophysical profile done within 72 hours of delivery. Theoretic risks of poor outcomes for different combinations of abnormal variables, calculated with Shortlife's formula, were compared with the actual risks observed (chi 2 tests). RESULTS: Two hundred forty-six fetuses had at least one abnormal biophysical profile variable with the risk of bad outcome, for a single abnormal variable, ranging from 8% (body movements) to 100% (tone) and increasing from 14% (any variable abnormal) to 63% (all variables abnormal). In most (57%) observed combinations of biophysical profile variables, significant differences between theoretic and actual risks of bad outcomes were found. By stepwise logistic regression the best predictive model contained all variables except fetal movement. CONCLUSIONS: Dynamic biophysical profile variables appear to be interdependent. Not all combinations of abnormal variables occur and specific combinations improve prediction of poor outcome. Risk-related scales for biophysical profile outcomes might prove superior to more conventional scoring systems.

Biophysics↗
PubMed2006

Project support of practical training in biophysics.

The Department of Biophysics ensures practical training in biophysics and related subjects for students of medical and health study programmes. Demonstrations of medical technology are an important part of this training. Teaching for Faculty of Sciences in biophysical study programmes becomes also very important. Some lectures and demonstrations of technology are involved, but the practical trainig is missing. About 1 mil. CZK for additional laboratory equipment was obtained from the HEIDF project No. 1866/ 2005 "The demonstration and measuring technology for education in medical biophysics and radiological physics" for measuring system DEWETRON for high frequency signal analysis, Fluke Ti30 IR camera, PM 9000B patient monitor, ARSENAL AF 1 fluorescence microscope, and Nikon Coolpix 4500 digital camera with accessories for microphotography. At the present time, further financial resources are being provided by a development project of Ministry of Education "Inter-university co-operation in biomedical technology and engineering using top technologies" in total amount of almost 5 mil CZK, whereas over 2 mil CZK from this project are reserved for student laboratory equipment. The main goal of this project is to ensure the participation of Medical Faculty in educational co-operation in the biomedical technology and engineering, namely with the Faculty of Electrical Engineering and Communication (FEEC), Brno University of Technology. There will be taught those areas of biophysics which are not covered by FEEC, thus forming a separate subject "General Biophysics". The following instruments will be installed: UV-VIS spectrophotometers, rotation viscometers, tensiometers, microscopes with digital image processing, cooled centrifuge, optical benches, and some smaller instruments for practical measurements.

Biophysics↗
PubMed2000

Effect of antenatal steroid administration on the fetal biophysical profile.

PURPOSE: Our objective was to determine whether antenatal steroid administration affects the biophysical profile score in fetuses. METHODS: A prospective study was conducted in 84 fetuses between 28 and 34 weeks' menstrual age at risk of preterm delivery. Two intramuscular injections of 12 mg of betamethasone were given to the mother 24 hours apart. All fetuses underwent biophysical profile testing prior to and between 24 and 48 hours after steroid administration. Biophysical profiles (including nonstress tests) were evaluated by two maternal-fetal medicine specialists blinded to the timing of steroid administration. Neonatal outcome, including Apgar score, menstrual age at delivery, admission to and length of stay in the neonatal intensive care unit, and mortality, was analyzed in all subjects. RESULTS: In 31 (37%; 95 confidence interval, 26.6-47.2%) of 84 cases, the biophysical profile score decreased at least 2 points after steroid administration. The most commonly affected variables were fetal breathing and the nonstress test. There was no significant difference in the neonatal outcome between the fetuses whose biophysical profile decreased and those whose did not. CONCLUSIONS: Biophysical profile scores were decreased in more than one third of fetuses within 48 hours of antenatal steroid administration, but neonatal outcome was not affected. Knowledge of this occurrence could avoid incorrect decision making regarding fetal well-being.

Adult↗
PubMed1990

The abnormal fetal biophysical profile score. V. Predictive accuracy according to score composition.

The relationship between last abnormal biophysical profile score, in total and by variable composition, and a spectra of abnormal perinatal outcome end points was examined in 525 fetuses. Highly significant inverse relationships between last test score and outcome were observed; relationships were linear for most end points and exponential for perinatal mortality end points. For biophysical profile scores less than or equal to 6, 25 of the 26 possible variable combinations were observed, at varying frequencies. For a biophysical profile score of 6, the positive predictive accuracy for some end points was significantly higher with either nonreactive nonstress test/fetal tone absent or nonreactive nonstress test/absent fetal breathing movement, and significantly lower with absent fetal breathing movement and decreased amniotic fluid volume. For a biophysical profile score of 4, the positive predictive accuracy for some end points was significantly higher with nonreactive nonstress test/absent fetal breathing movement/decreased amniotic fluid and was significantly lower with absent fetal movement/fetal breathing movement/fetal tone. No significant variation was observed for a biophysical profile score of 2. These data indicate that not all abnormal biophysical profile scores are equal.

Apgar Score↗