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At least 1,207 records · Page 67Linked to original sources
PubMed1994

Left ventricular diastolic dysfunction in lymphocytic myocarditis as assessed by Doppler echocardiography.

Pulsed-wave Doppler echocardiography of left ventricular (LV) inflows was performed in 30 consecutive patients with biopsy-proven lymphocytic myocarditis. There were 21 men and 9 women (mean age 50 +/- 15 years). LV ejection fraction was < or = 30% in 73% of the patients. Sixty-six percent were in New York Heart Association functional class III to IV. Peak early (E) velocity, late (A) velocity, deceleration time and filling pattern were assessed. These values were compared with a control population. E velocity in lymphocytic myocarditis was significantly higher than in control subjects (79 +/- 34 vs 67 +/- 14 cm/s, p = 0.0034). A velocity was lower in patients with myocarditis than in control subjects (38 +/- 20 vs 49 +/- 12 cm/s, p = 0.0001). Correspondingly, the E/A ratio was greater in the myocarditis group (2.5 +/- 1.3 vs 1.5 +/- 0.5, p < 0.0001). In particular, mean deceleration time in patients with myocarditis was significantly lower than that of control subjects (151 +/- 52 vs 194 +/- 30 ms, p < 0.0001). Diastolic filling patterns were abnormal in 29 of 30 patients (97%) with lymphocytic myocarditis, revealing a restrictive pattern in 25, abnormal relaxation in 4 and a normal pattern in 1. Lymphocytic myo-carditis is therefore associated with LV diastolic dysfunction of a predominantly restrictive pattern.

Adult↗
PubMed1975

Elevation of the fetal presenting part: A method of intrauterine resuscitation.

Traditional methods of diagnosing fetal distress have become obsolete. This diagnosis should be suggested by fetal heart rate patterns that demonstrate recurrent late or severe variable decelerations. Based upon our understanding of these patterns, methods of treating fetal distress in utero have evolved. This paper presents several cases in which elevation of the fetal presenting part was employed in an attempt to improve severe variable decelerations. It is suggested that this might be a salutary procedure when other methods of intrauterine resuscitation have failed.

Adult↗
PubMed1975

The oxytocin challenge test in the management of high-risk pregnancies.

Appearance of a repetitive late deceleration pattern following oxytocin-induced uterine contractions in the prepartum patient may indicate fetal compromise, while absence of this finding may reflect fetal well-being. In this study, 72 patients at risk for intrauterine asphyxia underwent 81 satisfactory oxytocin challenge tests. Eight tests in seven patients were interpreted as positive; 72, as negative; and one, as suspicious. In 64 patients with negative tests, no fetal deaths or neonatal asphyxial depressions were observed. One patient developed intrapartum fetal distress with late decelerations 8 days after a negative test and was delivered by cesarean section. The positive test appears to correlate meaningfully with other clinical parameters reflecting intrauterine compromise.

Adolescent↗
PubMed1976

Umbilical cord compression associated with amniotomy: laboratory observations.

Impairment of umbilical cord blood flow has been associated with periodic fetal heart rate changes termed "variable decelerations." These patterns may be observed after amniotomy. A chronic fetal rhesus monkey preparation has been used to investigate this clinical observation. Loss of amniotic fluid produced variable deceleration patterns, while restoration of amniotic fluid volume eliminated such changes. These experimental data demonstrate that amniotic fluid may be critical in protection of the cord and maintenance of normal umbilical cord blood flow.

Amniotic Fluid↗
PubMed1976

Clinical significance of fetal heart rate patterns during labor. I. Baseline patterns.

From a population of 2,774 high-risk patients monitored during labor, 1,304 single pregnancies in cephalic presentation and with direct monitoring for at least 1 hour before completion or cesarean-section were studied. The maternal and fetal clinical data and the tracings were hand reviewed, coded, and programmed for computer analysis. In the record were studied baseline, its changes (tachycardia, fixed, saltatory), the accelerations, and the decelerations (early, variable, late). Fifty-four per cent had some type of FHR deceleration. Accelerations were recorded in over 12 per cent of all cases and were associated with cord problems in 41 per cent. Subgrouping the patients by age of gestation (less than or equal to 36 weeks, 37 to 41 weeks, and greater than or equal to 42 weeks) revealed a 10 per cent prolonged gestation rate and only 6.8 per cent premature; these had a lower 5 minute Apgar score. Fetal weight and age were positively correlated with Apgar score. Baseline changes were much frequent among pre- and postmature infants, particularly tachycardia in the latter (40 per cent). The premature infants had a 25 per cent incidence of fetal distress and the postmature infants had 20 per cent. Neonatal morbidity and mortality rates were very high among premature infants and a mortality rate of 2.3 per cent was found among postmature infants. Saltatory pattern and particularly fixed baseline seem characteristic of prolonged gestation and placental insufficiency. With tachycardia, they constitute subtle symptoms of fetal distress.

Delivery, Obstetric↗
PubMed1977

The prediction of fetal oxygenation by an on-line computer analysis of fetal monitor output.

The deceleration delay index (DDI) is a statistical parameter computed by an on-line system which analyzes fetal monitor output for the temporal relationship between each uterine contraction and any associated deceleration of the fetal heart rate. A similar parameter describing this relationship is known to be quantitatively predictive of fetal oxygenation in the rhesus monkey, a species for which the level of fetal oxygenation is also known to be directly and progressively related to aberrations in the vital signs, to brain damage, and to fetal death. Thus, the DDI should be of significant, practical value in predicting fetal hypoxia at a time early enough to avert severe neonatal depression and/or hypoxic brain damage. A blind clinical trial of 106 parturients is presented which supports this concept by showing the DDI to be highly correlated with another oxygenation-associated parameter, the one-minute Apgar score.

Apgar Score↗
PubMed1977

Intrapartum fetal asphyxia: clinical characteristics, diagnosis, and significance in relation to pattern of development.

The clinical and fetal heart rates and acid-base characteristics and their sequelae have been reviewed in 587 patients. The relevant clinical factors in the asphyxia group were the preterm fetus, the intrauterine growth retarded fetus, maternal toxemia, and midforceps delivery. The duration of the developing metabolic acidosis in the asphyxia group ranged from terminal to the last two hours of labor. Marked patterns of total decelerations and moderate and marked patterns of late decelerations are of predictive value in the diagnosis of intrapartum fetal asphyxia with a trend to an increased incidence in the longer duration categories, between four and two hours prior to delivery, and a significant increase in all categories during the last two hours of labor. The significance of intrapartum fetal asphyxia to the newborn infant is evident from the low Apgar scores, increased incidence of moderate and severe respiratory distress syndrome, and central nervous system complications in the asphixia group in relation to the normal group.

Acid-Base Equilibrium↗
PubMed1978

Effect of oxytocin and oral prostaglandin E2 on uterine contractility and fetal heart rate patterns.

The incidnce of uterine contractility and of abnormalities of fetal heart rate (FHR) pattern was determined in a series of 2,834 monitored gravid women with singleton pregnancies producing mature infants in vertex presentation. Those subjected to uterotonic agents for induction or augmentation of lbaor had significantly more tetanic contractions, baseline hypertonus, and coupling of contractions. Similarly, significantly more variable and late FHR decelerations occurred in stimulated labors, and these were concentrated primarily in those receiving oxytocin. The overall incidence of FHR decelerations associated with the use of prostaglandin E2 (PGE2) was comparable to that encountered in unstimulated labor. The similarity between the contractions of spontaineous labor and those labors produced by PGE2 is noted.

Female↗
PubMed1979

Acceleration of the fetal heart rate.

Acceleration of the fetal heart rate during contractions was usually followed by deceleration, and evidence is presented to show that it results from increased sympathetic drive and may be associated with fetal tissue hypoxia. However, the presence of accelerations are not serious and merely warn the obstetrician of the possibility of the occurrence of subsequent decelerations. The mechanism thought most likely to produce accelerations is uterine compression of the umbilical vein during contractions.

Bradycardia↗
PubMed1981

Numerical analysis of the human fetal heart rate: modulation by breathing and movement.

Signal averaging has been used to identify the modulation of fetal heart periods (pulse intervals) by body movements and breathing, identified by a real-time ultrasound scan in normal pregnancies of 37 to 39 weeks. Accelerations were associated with fetal movements and were accompanied by arrest of fetal breathing and a decrease in beat-to-beat variation. They were commonly succeeded by decelerations, with an increase in beat-to-beat variation, within 15 to 20 seconds. In the absence of gross accelerations or decelerations, fetal breathing was associated with a high-frequency modulation of heart periods, measureable as a small increase in beat-to-beat variation. There was clustering of this characteristic pattern around and within fetal breathing episodes, which suggests that it may be a more sensitive index of breathing than visual identification with ultrasound. The conclusions are: (1) the grosser episodic changes in fetal heart rate are associated with the regular repetition of a pattern of accelerations and movements repeated at intervals less than 2 minutes; (2) fetal breathing episodes are independent of these gross changes; (3) beat-to-beat variation alters in a complex fashion and in different directions in association with physiologic changes.

Electrocardiography↗
PubMed1981

Pregnancy outcome in the patient with a nonreactive nonstress test and a positive contraction stress test.

The pregnancy outcomes for 41 patients with high-risk pregnancies who had undergone antepartum fetal heart rate testing between July 5, 1977, and April 10, 1980, and demonstrated a nonreactive nonstress test (NST) and a positive contraction stress test (CST) were reviewed. The estimated gestational ages of the time of the positive CST ranged from 28 to 44 weeks' gestation. Of the 41 pregnant women with a positive CST, 30 were allowed to labor. The remaining 11 patients underwent immediate cesarean section (8) or were managed expectantly because of immature phospholipid profiles (3). In the laboring group, 60.0% had evidence of late decelerations. Cesarean section for persistent late decelerations was necessary in 33.3%. The overall cesarean section rate for the positive CST group was 58.5%. The neonatal outcome for these 41 pregnancies demonstrated 29.3% of fetuses to be growth retarded and 17.1% of fetuses to have congenital abnormalities. The overall perinatal mortality rate was 7.3%. This investigation further substantiates the increased fetal and neonatal risks associated with a nonreactive NST and a positive CST. Induction of labor with direct fetal monitoring should be attempted in a term gestation where the cervix is ready for induction of labor and where rapid intervention by cesarean section is possible.

Adolescent↗
PubMed1981

Numerical analysis of the human fetal heart rate: the quality of ultrasound records.

A method is described for the computerized numerical analysis of fetal heart periods (pulse intervals). It uses a digital filter to separate the record into its high- and low-frequency components and, after removal of baseline variation, identifies accelerations and decelerations of all sizes. It provides an objective method for separating episodes of high heart period variation, normally associated with fetal movements, from episodes of low variation. When Doppler ultrasound is used in the last 10 weeks of gestation, failure time averages 40%. Signal loss is not randomly distributed; it is on average 75% greater during episodes of high heart period variation, although it is not particularly associated with fetal movements as identified by nurse or patient. Nevertheless a comparison of simultaneous direct ECG and ultrasound records shows that the latter provide reasonable statistical measures of heart period variation, and also of accelerations and decelerations provided that signal loss is taken into account. The system thus provides a particularly useful adjunct to the analysis of antenatal human fetal heart rate records.

Abdomen↗
PubMed1982

Fetal heart rate and tissue pH changes associated with repetitive aortic occlusion in the pregnant dog.

Variations in fetal heart rate (FHR) and tissue pH (tpH) were studied simultaneously in 10 pregnant dogs at term during experimental fetal distress produced by subjecting the fetuses to short episodes of acute anoxia, which was produced by occlusion of thr maternal aorta. The fetal response to these anoxic episodes dependent on the initial value of the tpH. With tpH higher than or equal to 7.20, the tpH and FHR showed minimal or no response. With tpH between 7.20 and 7.10, the FHR showed a "delayed" deceleration and there was a sharp decline in tpH. With lower tpH, the variations in FHR and tpH were less accentuated. Also noted were unusual variations, such as "transient" or "irregular" FHR decelerations, and tpH "reactive alkalosis." In this acute experimental situation, tpH seemed to be a very sensitive indicator of fetal anoxia. The combined continuous monitoring of FHR and tpH for the diagnosis of fetal distress deserves further investigation.

Animals↗
PubMed1982

The development of fetal acidosis in the presence of an abnormal fetal heart rate tracing. I. The average for gestational age fetus.

An abnormal fetal heart rate (FHR) tracing is a sensitive indicator of positivity that disease exists, but the intrinsic predictive value of such a tracing is disappointingly low because of the large number of false positive results. Abnormal FHR tracings, defined as those having a persistent quantitative score of 4 or less, were measured against time and outcome. A baseline fetal scalp blood sample was taken. Twenty fetuses were acidotic at the first blood sample. There were 121 study cases, all of which were greater than 37 weeks' gestational age. All fetuses were average for gestational age. Amniotic fluid was clear, internal FHR tracings were initially normal, and the first pH was normal. A relative acidosis-free interval could be demonstrated during the first 90 to 100 minutes. Following this time period rapid cumulative acidosis was seen, which varied according to the FHR pattern observed. The P50 acidosis values for various patterns were late decelerations, 115 minutes; variable decelerations, 145 minutes; and flat line tracings, 185 minutes.

Acidosis↗
PubMed1982

Comparison of antepartum testing schemes for the management of the postdate pregnancy.

We analyzed the outcome results of 583 postdate pregnancies managed prospectively by one of three antepartum testing schemes, each predicated on the nonstress test. In scheme 1, we relied upon the contraction stress test for evaluation of the nonreactive nonstress test. In scheme 2, we used a modified biophysical profile to evaluate the nonreactive nonstress test. In addition, patients were tested semiweekly. In scheme 3, we added routine weekly ultrasound evaluation of amniotic fluid volume to scheme 2. Only in scheme 3 did we induce labor for decreased amniotic fluid volume or fetal cardiac decelerations irrespective of reactivity. The incidence of fetal distress, perinatal mortality, and perinatal morbidity was increased in babies with decelerations or decreased amniotic fluid volume. Nevertheless, outcome results in scheme 2 were improved over those with scheme 1 and were best with scheme 3. These results suggest a benefit to both semiweekly testing and liberalized criteria for intervention in postdate pregnancies. We also compared the outcome results of scheme 3 with those reported for schemes in which the weekly contraction stress test was used as the primary form of surveillance. We found the outcome results comparable in that both schemes showed minimal mortality and morbidity statistics but high intervention rates (25% to 30%). Differences in methodology and test criteria, however, make such comparisons less than ideal.

Amniotic Fluid↗
PubMed1984

Neurological control of fetal heart rate in 20 cases of anencephalic fetuses.

Fetal heart rate (FHR) is influenced by the central nervous system, cardiac automatism, biochemical factors, etc. Changes in FHR were correlated with the anatomic defect in autopsy material from 20 anencephalic infants, and, on this basis, the following hypotheses were formed, subject to later experimental proof. (1) The FHR baseline level is controlled by the medulla oblongata and vagus nerve. (2) The biphasic sleep-awake pattern is controlled by the cerebral cortex. (3) The midbrain is involved in the occurrence of acceleration. (4) A relative high level of short-term variability is shown when small lesions of the lesser central nervous system are present, but we cannot conclude that the cortex is critical for short-term variability. On the other hand, long-term variability seems to be correlated to the presence of the medulla oblongata and midbrain, and might be amplified by the cerebral cortex. (5) U-shaped decelerations are connected with the medulla oblongata, but V-shaped decelerations depend on intracardiac reflexes and myocardial stretch.

Anencephaly↗
PubMed1984

Continuous, noninvasive measurement of fetal oxygen and carbon dioxide levels in labor by use of mass spectrometry.

Clinical evaluation of the continuous, simultaneous measurement of fetal scalp surface oxygen and carbon dioxide partial pressures by mass spectrometry was undertaken for 52 labors. The mass spectrometer (MM8-80, V.G. Gas Analysis, Winsford, England) was easy to operate and had good long-term stability. The mean drifts for both oxygen and carbon dioxide over the study periods were less than 2 mm Hg. The mean (+/- SD) cervical dilatation at the time of transducer application was 6.1 (+/- 1.9) cm and the mean (+/- SD) duration of the studies was 169 (+/- 122) minutes; 10.5% of the transducer applications were unsuccessful. Falls in fetal scalp surface oxygen levels and rises in carbon dioxide levels were more frequent with late than with variable and with variable than with early fetal heart rate decelerations and with increasing severity and frequency of decelerations. Fetal scalp surface pressure changes also occurred with fetal heart rate variability changes, including some related to behavioral state changes. There was not a constant reciprocal relationship between oxygen and carbon dioxide changes, and fetal heart rate patterns were not related to actual blood gas levels. Fetal scalp surface measurements were related to both fetal blood sample and umbilical artery results. Trends in both oxygen and carbon dioxide levels during the course of labor were compared and related to other fetal variables, and most of the time the scalp surface measurements were an accurate guide to systemic blood gas levels. Maternal oxygen administration resulted in significant increase in fetal scalp surface oxygen levels, and on two of eight occasions it also led to decreases in fetal carbon dioxide levels. Scalp surface gas measurement by means of mass spectrometry is a powerful new method of intrapartum fetal monitoring, which should increase the precision of fetal surveillance as well as allow the accurate assessment of both established and new methods for optimizing labor and delivery.

Carbon Dioxide↗
PubMed1985

Meconium below the vocal cords at delivery: correlation with intrapartum events.

Intrapartum events were studied in 272 patients with meconium-stained amniotic fluid. All infants underwent DeLee suction followed by intubation and 58 of 272 had meconium present below the vocal cords at delivery. Neither the total duration of variable fetal heart rate decelerations or a continuous saltatory pattern nor the presence or absence of late decelerations could be related to an increased risk of meconium below the vocal cords. When a rising baseline fetal heart rate and decreased variability were present as well, a significantly greater proportion of patients had meconium below the vocal cords. Routine obstetric and pediatric suctioning did not prevent the single death that occurred in a fetus who had deep meconium aspiration in utero.

Amniotic Fluid↗