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A Capponi

Publications and source records attributed to A Capponi.

At least 19 recordsLinked to original sources
PubMed2004

Accuracy of the ICD-9 codes for identifying TIA and stroke in an Italian automated database.

The object of this study was to evaluate the sensitivity and positive predictive value (PPV) of International Classification of Diseases, 9th revision (ICD-9) codes 430-438 in the Sistema Informativo Sanitario Regionale (SISR), an Italian health care automated database. We compared the SISR with a manual search of all cases of transient ischaemic attack (TIA) and stroke discharged from the Novara Hospital, NW Italy. Results were as follows: SISR list: 1017 patients; manual list 1005. Linked: 896; false negatives: 109; false positives: 121. Sensitivity of codes 430-438: 77% at the primary position only and 89% at either the primary or secondary position; PPV: 93% and 88%. Sensitivity and PPV for specific codes vs. each subcategory (sensitivity at the primary position only/any position; PPV at the primary position only/any position): for 430, subarachnoid haemorrhage (33/35%; 46/43%); for 431, cerebral haemorrhage (57/59%; 77/75%); for 434, cerebral infarction (35/37%; 90/87%); for 436, stroke of unknown type (29/29%; 19/16%); and for 435, TIA (75/82%; 80/78%). The SISR database has a high PPV; sensitivity is high for TIA, but low for specific stroke ICD codes.

Aged↗
PubMed2003

Abnormal cardiac function in fetuses with increased nuchal translucency.

OBJECTIVE: To evaluate cardiac function in structurally and chromosomally normal fetuses with increased nuchal translucency (NT). METHODS: Forty-two structurally and chromosomally normal fetuses with increased NT at 11-14 weeks of gestation underwent fetal echocardiographic examination at 20-23 weeks. Fifty fetuses with normal NT values were considered as controls. Pulmonary and aortic peak velocity and time to peak velocities were measured as indices of ventricular systolic function. The ratios between the E-wave and A-wave (E/A) and the ratios between the E-wave and time velocity integral (E/TVI) at the level of both atrioventricular valves were evaluated as indices of ventricular diastolic function. RESULTS: In fetuses with increased NT the E/A ratios were significantly decreased when compared to control fetuses at the level of both the mitral (0.52 +/- 0.09 vs. 0.60 +/- 0.10, P = 0.0002) and tricuspid (0.51 +/- 0.09 vs. 0.61 +/- 0.09, P < 0.0001) valves. Similar results were found for the E/TVI ratios (mitral valve 4.79 +/- 1.03 vs. 5.63 +/- 1.23, P = 0.0007 and tricuspid valve 4.40 +/- 0.88 vs. 5.19 +/- 0.82, P < 0.0001). No significant relationship was found between the degree of NT and the abnormalities in Doppler indices. There were no significant differences in Doppler systolic indices. CONCLUSION: Structurally and chromosomally normal fetuses with increased NT have low E/A and E/TVI ratios at 20-23 weeks of gestation. These findings might indicate cardiac diastolic dysfunction.

Blood Flow Velocity↗
PubMed2000

Blood flow velocity waveforms from fetal peripheral pulmonary arteries in pregnancies with preterm premature rupture of the membranes: relationship with pulmonary hypoplasia.

OBJECTIVES: To measure fetal peripheral pulmonary artery velocity waveforms by Doppler ultrasonography in pregnancies complicated by premature rupture of membranes under 24 weeks' gestation and to relate the Doppler indices to the development of fetal pulmonary hypoplasia. DESIGN: A prospective longitudinal study of fetal peripheral pulmonary artery velocity waveforms from premature rupture of membranes to delivery. SUBJECTS: Twenty pregnancies complicated by premature rupture of membranes before 24 weeks of gestation and delivering after 26 weeks. METHODS: Peripheral pulmonary artery velocity waveforms were recorded by Doppler technique at weekly intervals until delivery and Pulsatility Index (PI) calculated. Pregnancies were managed conservatively according to an institutional management protocol. Pulmonary hypoplasia was defined at autopsy by lung/body weight ratios and radial alveolar counts. Pulsatility Indices of fetuses developing pulmonary hypoplasia were compared with those with a normal lung development. RESULTS: After premature rupture of membranes PI values were higher than normal reference limits for gestation, but no differences were found between the six fetuses which developed pulmonary hypoplasia and the remaining 14 fetuses with normal lung development. In this latter group PI values progressively decreased with advancing gestation (ANOVA for repeated measurements F = 11.61; P < or = 0.001), while they increased in fetuses developing pulmonary hypoplasia (F = 8.44; P < or = 0.001). As a consequence of these opposite trends significant differences in PI values were present between the two groups of fetuses from 2 weeks after the premature rupture of membranes. Two weeks after the premature rupture of membranes a PI value from the peripheral pulmonary arteries above the 95th centile had a sensitivity of 62.5%, specificity of 94.6%, positive predictive value of 83.3%, negative predictive value of 78.5% and relative risk of 3.88 (95th confidence interval 1.34-11.28) for the prediction of pulmonary hypoplasia. CONCLUSION: The measurement of peripheral pulmonary velocity waveforms may help to establish the risk of developing pulmonary hypoplasia in pregnancies complicated by premature rupture of membranes.

Adult↗
PubMed1998

The value of transvaginal ultrasonographic examination of the uterine cervix in predicting preterm delivery in patients with preterm premature rupture of membranes.

The objective of this study was to compare the value of ultrasonographic assessment of the uterine cervix and amniotic fluid tests in the prediction of the interval from admission to delivery in patients with preterm premature rupture of membranes. Ninety-two patients admitted to the hospital for preterm premature rupture of membranes between 24 and 32 weeks of gestation underwent both transabdominal amniocentesis and transvaginal ultrasonographic evaluation of the uterine cervix. Amniotic fluid analyses included cultures for aerobic and anaerobic bacteria, mycoplasmas and ureaplasmas, white blood cell count and glucose and interleukin-6 determinations. The ultrasonographic variables evaluated were cervical length, presence of funneling and cervical index ((funnel length + 1)/cervical length). The outcome measure was the interval from admission to delivery. The median interval from admission to delivery was 4.5 days (range 0-36). An abnormal uterine cervix was associated with a short time interval (cervical length < or = 20 mm, median 2 days, range 0-14 vs. median 6 days, range 0-36; p < or = 0.0001; presence of funneling, median 3 days, range 1-31 vs. median 8 days, range 0-36; p < or = 0.001; cervical index > 0.50, median 2 days, range 0-7 vs. median 8 days, range 1-36; p < or = 0.0001). However, interleukin-6 concentration in the amniotic fluid was the best predictor of the interval from admission to delivery when compared to the ultrasonographic indices and to all the amniotic variables considered. Moreover, when a multiple model was applied, the cervical index significantly and independently improved the performance of interleukin-6 in the prediction of the interval from admission to delivery. These data suggest that the combined use of the amniotic fluid interleukin-6 assay and the cervical index in patients with preterm premature rupture of membranes provides a good prediction of the interval from admission to delivery, thus identifying a subgroup of patients at high risk of imminent delivery.

Adult↗
PubMed1998

Ultrasonographic assessment of the uterine cervix and interleukin-8 concentrations in cervical secretions predict intrauterine infection in patients with preterm labor and intact membranes.

OBJECTIVE: Interleukin-8 concentrations in cervical secretions have been related to microbial invasion of the amniotic cavity and histological chorioamnionitis. Since a short uterine cervix may be a risk factor for intrauterine infection, we set out to determine the interrelationship between cervical-secretion interleukin-8 concentration, cervical length measured by transvaginal sonography and intrauterine infection in women with preterm labor and intact membranes. DESIGN: The study group comprised 144 pregnant women admitted to hospital for preterm labor and intact membranes. At admission, interleukin-8 in cervical secretions was assayed. The uterine cervix was evaluated by transvaginal sonography and the cervical index (funnel length + 1)/cervical length) was measured. In all cases, amniotic fluid was obtained by amniocentesis immediately after cervical examination and was cultured for aerobic and anaerobic bacteria including Ureaplasma ureolyticum and Mycoplasma hominis. Placentas were analyzed at delivery for the presence of histological chorioamnionitis. RESULTS: Forty-three per cent (62/144) of pregnancies delivered preterm and 12.5% (18/144) of the amniotic fluid cultures were positive. Placentas were available from 54 pregnancies which delivered preterm and histological chorioamnionitis was found in 59.2% (32/54) of the cases. Interleukin-8 concentrations in cervical secretions were significantly higher in the presence of microbial invasion of the amniotic cavity (median 1191.5 ng/ml, range 812-5234 ng/ml vs. median 109 ng/ml, range 12-2231 ng/ml; p < or = 0.0001) and histological chorioamnionitis (median 982.5 ng/ml, range 430-5234 ng/ml vs. median 435 ng/ml, range 40-1750 ng/ml; p < or = 0.0001). Similarly, higher values for cervical index were obtained in the presence of a positive amniotic fluid culture (median 1.23, range 0.35-5.88 vs. median 0.29, range 0.024-4.85; p < or = 0.0001) or histological chorioamnionitis (median 1.18, range 0.043-5.88 vs. median 0.562, range 0.040-2.48; p = 0.011). Multiple logistic regression analysis indicates significant independent associations with a positive amniotic fluid culture and histological chorioamnionitis for the cervical interleukin-8 concentrations (amniotic fluid culture positive > or = 850, histological chorioamnionitis > or = 450) and for the cervical index (amniotic fluid culture positive < or = 0.58, histological chorioamnionitis < or = 0.56). CONCLUSIONS: Intrauterine infection is associated with increased interleukin-8 concentrations in cervical secretions and a short cervix. Their combined analysis may reduce the indications for invasive procedures and improve the selection of women in preterm labor who may benefit from antimicrobial treatment.

Adult↗
PubMed1998

Interleukin-6 concentrations in cervical secretions in the prediction of intrauterine infection in preterm premature rupture of the membranes.

The objective of this study was to determine the value of interleukin-6 (IL-6) in cervical secretion to diagnose microbial invasion of the amniotic cavity in patients with premature rupture of the membranes. Cervical secretions were sampled immediately before amniocentesis in 124 patients with singleton pregnancies and preterm premature rupture of the membranes. Gestational age ranged between 24 and 32 weeks. Amniotic fluid was cultured and IL-6 measured in amniotic fluid and cervical secretions. A total of 33.8% (21/124) of the amniotic fluid cultures had positive results. In cervical secretions the median concentration of IL-6 was 672 pg/ml (range 5-1,250) in the presence of intra-amniotic infection in contrast to 95.5 pg/ml (range 12-640) in women with negative amniotic fluid culture (p </=0.001). There were no differences between IL-6 concentrations in the cervical secretions of patients with or without obvious leakage of amniotic fluid. A significant relationship was found between IL-6 levels in amniotic fluid and in cervical secretions (rho = 0.74, p </=0.001). An IL-6 level in cervical secretions >200 pg/ml had a sensitivity of 78.5%, a specificity of 73.1% and a relative risk of 4.6 for intra-amniotic infection. Receiver-operator characteristics curve analysis showed that IL-6 assay in cervical secretions is comparable to IL-6 assay in amniotic fluid in predicting intra-amniotic infection (p = 0.468). In conclusion, intra-amniotic infection is associated with increased levels of IL-6 and concentrations in cervical secretions are related to amniotic levels. The measurement of IL-6 in cervical secretions may help to noninvasively identify intra-amniotic infection among pregnancies with preterm premature rupture of membranes.

Adult↗
PubMed1998

Ultrasonographic and Biochemical Markers of Preterm Labor.

> At present preterm delivery is the leading cause of perinatal morbidity and mortality and its incidence is remained stable during the past 10 years. Conventional methods of identifying patients at risk of preterm delivery such as obstetrics history, demographic factors or evaluation of uterine contractions and cervix by digital examination show disappointintly low sensitivity and positive predictive value. In this review we describe new ultrasonographic and biochemical approaches that have been recently proposed to screen for preterm labor both in patients with intact and with premature rupture of the membranes. The ultrasonographic detection of a short uterine cervix and/or of a dilation of the internal os, expression of weakening of the lower uterine segment or cervical ripening, seems to efficiently predict patients at risk of preterm delivery. The efficiency of this marker may be improved by the association with the assay of fetal fibronectin or pro inflammatory cytokines (interleukin-6 and interleukin-8) in cervical secretions. Further by the concentrations of interleukin-6 and interleukin-8 in cervical secretions seems to be possible to predict among patients in preterm labor those secondary to subclinical endoamniotic infection or chorioamnionitis. The use of these new markers in the future may allow a better identification of patients at risk of preterm labor and a proper selection of the treatment (medical or surgical) required for such patients.

Journal Article↗
PubMed1997

Indomethacin modifies the fetal hemodynamic response induced by percutaneous umbilical blood sampling.

OBJECTIVE: Percutaneous umbilical blood sampling induces a marked decrease of impedance to flow in the umbilical artery. Because these changes are believed to be the result of the release of prostanoids, we conducted a study to determine whether indomethacin administration before percutaneous umbilical blood sampling affects the hemodynamic response induced by this procedure. STUDY DESIGN: Percutaneous umbilical blood sampling was performed in 20 singleton pregnancies that were treated for 3 days before the procedure with indomethacin (25 mg orally 6 hours apart) as tocolytic agent and in 22 untreated pregnancies. All the procedures were uncomplicated, and sampling of the umbilical vein was confirmed by blood pressure measurement at the time of the procedure. The umbilical artery pulsatility index and the fetal heart rate were measured immediately before and after the procedure. The first and last aliquots of umbilical vein plasma obtained at the beginning and closing of the procedure were assayed for endothelin-1, 6-keto-prostaglandin F1 alpha and thromboxane B2. RESULTS: In untreated pregnancies percutaneous umbilical blood sampling induced a decrease of the umbilical artery pulsatility index (p < 0.0001) and an increase in 6-keto-prostaglandin F1 alpha (p < 0.001) and endothelin-1 levels (p = 0.001), whereas no significant changes were present in fetal heart rate and thromboxane B2 levels. In pregnancies treated with indomethacin, 6-keto-prostaglandin F1 alpha, and thromboxane B2, concentrations at the beginning of the procedure were both significantly less (p < 0.0001) than those found in untreated pregnancies. In pregnancies treated with indomethacin percutaneous umbilical blood sampling did not affect umbilical artery pulsatility index, and 6-keto-prostaglandin F1 alpha and thromboxane B2 levels did not vary during the procedure. However, endothelin-1 (p < 0.001) and fetal heart rate (p < 0.0001) increased after the procedure. CONCLUSION: Indomethacin affects the fetal hemodynamic response to percutaneous umbilical blood sampling by inhibiting the release of prostanoids and the fall in umbilical artery pulsatility index. Under this condition the fetus adapts to the procedure by increasing the heart rate.

6-Ketoprostaglandin F1 alpha↗
PubMed1997

Splenic artery velocity waveforms in small-for-gestational-age fetuses: relationship with pH and blood gases measured in umbilical blood at cordocentesis.

OBJECTIVE: Our purpose was to relate velocity waveforms from the splenic artery with pH and blood gas levels measured at cordocentesis in small-for-gestational-age fetuses and to compare the diagnostic efficiency of splenic artery waveforms with that of other fetal arterial and venous vessels in predicting acid-base status. STUDY DESIGN: Cross-sectional recordings from the splenic artery were obtained by color and pulsed Doppler techniques in 316 appropriately grown fetuses, 12 small-for-gestational-age fetuses with normal umbilical artery velocity waveforms (group 1), and 30 small-for-gestational-age fetuses with abnormal umbilical artery velocity waveforms (group 2). Measurements of splenic artery pulsatility index values in small-for-gestational-age fetuses were compared with those of appropriate-for-gestational-age fetuses. Associations of splenic artery pulsatility index with Po2, Pco2, and pH values measured at cordocentesis were examined and compared with those of umbilical artery, middle cerebral artery, and inferior vena cava. RESULTS: In appropriately grown fetuses pulsatility index values from the splenic artery decrease with advancing gestation (r = 0.51, p < 0.0001). Splenic artery pulsatility index values are lower in group 2 (p < 0.001) but not in group 1 small-for-gestational-age fetuses (p = 0.211). The amplitude of the decrease in the pulsatility index is significantly associated with fetal hypoxemia (r = 0.646, p < 0.001), acidemia (r = 0.593, p < 0.001) and hypercapnia (r = 0.577, p < 0.001). However, logistic regression demonstrates that hypoxia is better predicted by middle cerebral artery pulsatility index, whereas hypercapnia and acidosis are more closely associated with the percent of reverse flow in inferior vena cava. CONCLUSION: A decrease in the splenic artery pulsatility index occurs in small-for-gestational-age fetuses in the presence of abnormal pH and blood gas values, but a more accurate assessment of acid-base status may be obtained with the study of the middle cerebral artery and inferior vena cava.

Blood Flow Velocity↗
PubMed1997

Atrial natriuretic peptide levels in fetal blood in relation to inferior vena cava velocity waveforms.

OBJECTIVE: To determine whether blood levels of atrial natriuretic peptide in small for gestational age (SGA) fetuses are related to Doppler indices measured in arterial and venous vessels. METHODS: Atrial natriuretic peptide was assayed in fetal blood obtained at funipuncture in 42 third-trimester fetuses, of whom 11 were appropriate for gestational age (AGA) and 31 were SGA. Small for gestational age fetuses were divided into three groups according to Doppler findings in the umbilical artery and inferior vena cava: 1) normal in both vessels (n = 10); 2) abnormal in the umbilical artery but normal in the inferior vena cava (n = 10); and 3) abnormal in both vessels (n = 11). Atrial natriuretic peptide levels were related to Doppler indices and acid-base status of the fetal blood. RESULTS: Small for gestational age fetuses with abnormal waveforms in both vessels had higher atrial natriuretic peptide blood levels (median 544.8 pg/mL, range 404.2-1112.3) compared with AGA fetuses (median 316.8 pg/mL, range 159.3-470.1; P < or = .001), SGA fetuses with normal waveforms only in both vessels (median 299.8 pg/mL, range 242.6-480.5; P < or = .001), and SGA fetuses with abnormal waveforms only in the umbilical artery (median 367.6 pg/mL, range 192.7-748.9; P = .002). Blood levels of atrial natriuretic peptide were significantly related to the preload index in the inferior vena cava (p = 0.554, P < or = .001). This relation remained significant when the analysis was restricted to the SGA fetuses with abnormal waveforms in the umbilical artery and the inferior vena cava (p = 0.673, P = .03). CONCLUSIONS: Small for gestational age fetuses with abnormal velocity waveforms in the inferior vena cava have significantly higher concentrations of atrial natriuretic peptide. This may represent a compensatory mechanism in the SGA fetus for regulation of an abnormal hemodynamic condition.

Adult↗
PubMed1997

The diagnostic value of interleukin-8 and fetal fibronectin concentrations in cervical secretions in patients with preterm labor and intact membranes.

The objectives of this study were 1) to evaluate interleukin-8 concentrations in cervical secretions in predicting preterm delivery, microbial invasion of the amniotic cavity and histologic chorioamnionitis in patients with preterm labor and intact membranes and 2) to compare the diagnostic value of interleukin-8 with fetal fibronectin determinations in predicting preterm delivery, microbial invasion of the amniotic cavity and histologic chorioamnionitis in patients with preterm labor and intact membranes. Interleukin-8 and fetal fibronectin were assayed in cervical secretions in 106 patients with singleton pregnancies and intact membranes admitted for preterm labor. Amniotic fluid obtained by amniocentesis was cultured and placentas (No = 43) analyzed for the presence of chorioamnionitis. The prevalence of pregnancies delivered preterm was 46.2% (49/106) and 15.09% (16/106) of amniotic fluid cultures were positive. Interleukin-8 levels in cervical secretions were significantly increased in patients who delivered preterm (p < or = 0.0001), in presence of positive amniotic fluid culture (p = 0.0016) and histological chorioamnionitis (p = 0.008) than in patients with negative findings. Receiver-operator characteristics curve analysis showed that an interleukin-8 value > 450 pg/ml is comparable to that of a fetal fibronectin value > 50 ng/ml in predicting preterm delivery (p = 0.247). Among patients who delivered preterm interleukin-8 concentrations > 860 pg/ml predicted a positive amniotic fluid culture with a sensitivity of 81.2% and a specificity 66.6%. Further, in patients who delivered preterm and had a negative amniotic fluid culture, IL-8 concentrations > 480 pg/ml predicted histological chorioamnionitis with a sensitivity 78.5% and specificity 61.5%. A positive fetal fibronectin > 50 ng/ml was not predictve of either a positive amniotic fluid culture or the presence of histological chorioamnionitis. In conclusion, increased concentrations of interleukin-8 and fetal fibronectin are associated with impending delivery and their diagnostic value seems comparable. However, interleukin-8 concentrations identify patients at risk of a positive amniotic fluid culture and the presence of histological chorioamnionitis. Measurement of interleukin-8 in cervical secretion is a non-invasive method to identify patients at risk for both preterm delivery and intrauterine infection.

Adult↗
PubMed1996

The value of fetal fibronectin in cervical and vaginal secretions and of ultrasonographic examination of the uterine cervix in predicting premature delivery for patients with preterm labor and intact membranes.

OBJECTIVE: We compared the diagnostic performances of fetal fibronectin assay of cervical and vaginal secretions and of transvaginal ultrasonographic evaluation of the uterine cervix in the prediction of preterm delivery of patients presenting with preterm labor and intact membranes. STUDY DESIGN: One hundred eight patients admitted to the hospital for preterm labor and with intact membranes underwent assay of fibronectin in the cervical and vaginal secretions and transvaginal ultrasonographic evaluation of the uterine cervix. The ultrasonographic parameters evaluated were cervical length, presence of funneling, and cervical index ([Funnel length + 1]/Cervical length). Outcome measures were occurrence of preterm delivery, defined as birth before the thirty-seventh week of gestation, and the admission-to-delivery interval. RESULTS: Forty-seven patients (43.5%) were delivered preterm. Receiver characteristic curve analysis showed that a level of fetal fibronectin in cervical secretions > or = 60 ng/ml had the highest diagnostic performance in predicting preterm delivery (sensitivity 80.9%, specificity 83.6%). Multiple stepwise logistic regression analysis indicated that the cervical index significantly improved the prediction of preterm delivery achieved by the fetal fibronectin assay. In patients with cervical secretion fibronectin levels > or = 60 ng/ml, survival analysis showed a shorter admission-to-delivery interval in the presence of an abnormal cervical index (p < or = 0.001). CONCLUSIONS: The assay of fetal fibronectin in cervical secretions is more accurate than ultrasonographic evaluation of the uterine cervix in the prediction of preterm delivery. Combined use of the fetal fibronectin assay and the cervical index improves the diagnostic efficiency and allows prediction of the admission-to-delivery interval, identifying a subgroup of patients who may require aggressive treatment.

Adult↗
PubMed1996

Interleukin-6 concentrations in cervical secretions identify microbial invasion of the amniotic cavity in patients with preterm labor and intact membranes.

OBJECTIVE: The objectives of this study were to determine whether cytokine levels in cervical secretions were increased in the presence of microbial invasion of the amniotic cavity in patients with preterm labor and intact membranes and to relate concentrations to cytokine levels in amniotic fluid, cervicovaginal microflora, and the presence of chorioamnionitis. STUDY DESIGN: Cervical secretions were sampled immediately before amniocentesis in 92 patients admitted for preterm labor with singleton pregnancies and intact membranes. Amniotic fluid was cultured and the following cytokines were measured in amniotic fluid and cervical secretions: interleukin-1 beta, interleukin-1 receptor antagonist, tumor necrosis factor-alpha, and interleukin-6. The cervicovaginal microflora and placentas (n = 42) were also analyzed. RESULTS: A total of 19.56% (18/92) of the amniotic fluid cultures had positive results. All the cytokines tested showed significantly higher levels in cervical secretions in the presence of intraamniotic infection. There were significant relationships between the concentrations of interleukin-6 and interleukin-1 receptor antagonist in amniotic fluid and cervical secretions. A concentration of interleukin-6 in cervical secretions > 410 pg/ml had a sensitivity of 66.8% and a specificity of 90.5% and a relative risk of 7.7 for intraamniotic infection, higher than the other cytokines tested. There were no relationships between the presence of bacterial vaginosis and cervicovaginal pathogens and cervical cytokine levels. In the presence of chorioamnionitis, cervical concentrations of interleukin-6 and interleukin-1 receptor antagonist were significantly increased in spite of negative amniotic fluid culture results. CONCLUSION: The measurement of interleukin-6 in cervical secretions may help to noninvasively identify intraamniotic infection among pregnancies with preterm labor and intact membranes.

Adult↗
PubMed1996

Doppler indices from inferior vena cava and ductus venosus in predicting pH and oxygen tension in umbilical blood at cordocentesis in growth-retarded fetuses.

The objective of this study was to assess the value of Doppler indices calculated from the inferior vena cava and ductus venosus in the identification of acidemia and hypoxemia as determined by pH and gas analysis of fetal blood obtained by cordocentesis in growth-retarded fetuses. Doppler measurements were performed in the inferior vena cava and ductus venosus in 209 normally grown fetuses and in 89 growth-retarded fetuses. All growth-retarded fetuses were free from structural and chromosomal abnormalities, and uteroplacental insufficiency characterized by Doppler changes in the umbilical and middle cerebral arteries was the most likely etiology of the growth defect. In this group of fetuses, Doppler recordings were performed immediately before cordocentesis. Ten different indices were calculated from venous velocity waveforms, and reference limits for gestation were constructed by the cross-sectional analysis of data from normally grown fetuses. Logistic regression and receiver operator characteristic curve analysis were performed to examine the relationship between Doppler indices and acid-base status. The pre-load index (peak velocity during atrial contraction/peak velocity during systole) in the inferior vena cava was the best explanatory variable for acidemia (chi 2 = 48.33; p < or = 0.001). Hypoxemia was predicted less well by venous indices and the best results were achieved by the S/A ratio in the ductus venosus (chi 2 = 9.46; p < or = 0.005). In conclusion, our data suggest that acidosis in growth-retarded fetuses may be non-invasively identified by Doppler measurements of the inferior vena cava and that a higher efficiency can be achieved by the use of the pre-load index.

Acidosis↗
PubMed1996

Blood flow velocity waveforms from peripheral pulmonary arteries in normally grown and growth-retarded fetuses.

The objective of this study was to describe blood flow velocity waveforms of fetal peripheral pulmonary arteries in normally grown and growth-retarded fetuses. Doppler studies were performed in 182 normally grown fetuses (gestational age 18-40 weeks) and in 61 growth-retarded fetuses (gestational age 24-36 weeks) that were free from structural and chromosomal abnormalities and whose umbilical and middle cerebral artery Doppler findings suggested uteroplacental insufficiency as the most likely etiology of the growth defect. The pulsatility index was used to quantify the velocity waveforms. Successful recordings were obtained in 90.1% of the normally grown and 93.4% of the growth-retarded fetuses. In normally grown fetuses the pulsatility index values significantly decreased with advancing gestation. In growth-retarded fetuses the pulsatility index values were significantly elevated compared to those of normal fetuses. A significant relationship was observed between the severity of hypoxia and pulsatility index values from the peripheral pulmonary arteries in 29 fetuses in which Doppler recordings were obtained immediately before cordocentesis. In conclusion, these data show that in normal fetuses the Doppler-measured impedance to flow in the peripheral pulmonary circulation decreases with advancing gestation. Impedance to flow in the lungs is elevated in the presence of growth retardation and this increase is related to the severity of fetal hypoxia.

Acid-Base Equilibrium↗
PubMed1996

Release of vasoactive agents during cordocentesis: differences between normally grown and growth-restricted fetuses.

OBJECTIVE: The purpose of this study was to evaluate whether cordocentesis is associated with the release of vasoactive substances and whether there are differences between normally grown and growth-restricted fetuses. STUDY DESIGN: 6-Keto-prostaglandin F1 alpha (the stable metabolite of prostacyclin), endothelin-1, and cyclic guanosine monophosphate were measured in fetal blood at the beginning and closing of cordocentesis in 30 normally grown fetuses and 25 growth-restricted fetuses. This latter group was characterized by abnormal Doppler index values in umbilical artery and middle cerebral artery, suggestive of chronic hypoxemia as the causative factor of the impaired growth. In six growth-restricted fetuses bradycardia occurred at the end of the procedure. Umbilical artery pulsatility index was measured by Doppler ultrasonography immediately before and after the procedure. RESULTS: The median interval between the two blood samples obtained by cordocentesis was 90 seconds (range 60 to 320 seconds). During this interval a significant rise of 6-keto-prostaglandin F1 alpha (p < or = 0.0001) and endothelin-1 (p = 0.03) was evidenced in normally grown fetuses. The increase in 6-keto-prostaglandin F1 alpha was significantly related (r = 0.52, p = 0.002) to the fall of umbilical artery pulsatility index occurring after the procedure. In growth-restricted fetuses cordocentesis induced a marked increase of endothelin-1 (p = 0.0002), which was significantly related to the severity of acidosis (r = 0.52, p = 0.018), whereas no modifications were evidenced for the other agents tested. The increase of endothelin-1 was higher in those growth-restricted fetuses showing bradycardia at the end of the procedure than in growth-restricted fetuses that did not (p = 0.04). The variations of the vasoactive substances assayed were not significantly related to the type of procedure (transamniotic or transplacental), the amount of blood aspirated during the procedure, the interval elapsing between the first and second samples, the gestational age at which the procedure was performed, and the degree of fetal smallness. CONCLUSION: Cordocentesis induces the rapid release of vasoactive substances and the effect differs between normally grown and growth-restricted fetuses. This may explain the different hemodynamic response and the higher rate of complications occurring in the latter group after cordocentesis.

6-Ketoprostaglandin F1 alpha↗
PubMed1996

The effects of fetal blood sampling and placental puncture on umbilical artery and fetal arterial vessels blood flow velocity waveforms.

This study was performed to investigate whether fetal blood sampling and/or transplacental puncture are associated with changes of blood flow velocity waveforms in umbilical artery and fetal circulation. The pulsatility index (PI) was measured from umbilical artery, thoracic descending aorta, renal artery, and middle cerebral artery immediately before and after fetal blood sampling (n = 28) or third trimester amniocentesis (n = 32). No significant changes in PI values were evidenced after amniocentesis performed either transamniotically (n = 21) or transplacentally (n = 11). Fetal blood sampling induced a significant decrease of PI values in all the vessels investigated. However, in presence of a transplacental procedure (n = 15) the amplitude of the decrease of PI in umbilical artery was significantly higher than after a transamniotic procedure (n = 13), while no differences were evidenced in the other vessels tested. These findings indicate that umbilical cord puncture at the time of fetal blood sampling is associated with a decrease in PI in umbilical artery and several peripheral arterial vessels. The isolated placental puncture does not induce Doppler-detectable hemodynamic effects, while in conjunction with cord needling, it increases the amplitude of the effects in umbilical artery.

Amniocentesis↗