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At least 19 recordsLinked to original sources
PubMed1990

Evaluation of variable decelerations of fetal heart rate with the deceleration index: influence of associated abnormal parameters and their relation to the state and evolution of the newborn.

The deceleration index of the Fetal heart rate (FHR) (Acién P. et al. (1979) J. Perinat Med 7, 7-18) was used to analyze 157 cardiotocographic registers that displayed variable deceleration during labor. We have related the deceleration index value to perinatal results and to other abnormal parameters of FHR. An increase in neonatal pathology was observed in the deceleration group compared to a group of 50 controls with normal FHR, when the deceleration index was greater than 150 and specially if it was greater than 200. The association of other abnormal parameters of FHR (especially absence of variability between or during decelerations, absence of transitory ascents, presence of tachycardia and, of less importance, absence of ascents at the beginning of deceleration or presence of overshoot acceleration following deceleration) yields a worse prognosis for the fetus than does an increased deceleration index alone. The deceleration index is a good method for evaluation of variable decelerations of FHR, and is well correlated to the condition of the newborn.

Apgar Score↗
PubMed2002

V-shaped deceleration differs in the pattern of carotid blood flow from variable deceleration provoked by cord compression.

OBJECTIVE: To investigate whether V-shaped decelerations in fetal heart rate tracing are a physiologic response to fetal movements or secondary to cord compression. STUDY DESIGN: Six pregnant sheep and their fetuses (115-125 days of gestation) were surgically instrumented and studied. Fetal electrocardiogram, carotid blood flow, arterial blood pressure and fetal movement were continuously monitored for 24 hours. Following the undisturbed 24 hour recording, these parameters were monitored during umbilical cord compression (n = 6). Differences in these parameters between V-shaped decelerations and decelerations provoked by cord compressions were examined. RESULTS: Elevation of blood pressure and decreased carotid blood flow were observed coincidentally with the initiation of V-shaped decelerations. In cord compression, elevation of both blood pressure and carotid blood flow were followed by a decreased heart rate. V-shaped decelerations exhibited a different alteration of carotid blood flow compared to decelerations caused by umbilical cord compression. CONCLUSION: V-shaped deceleration is a physiologic response secondary mainly to fetal movements and is not caused by cord compression.

Animals↗
PubMed1986

Growth decelerations among under 5-year-old children in Kasongo (Zaire). I. Occurrence of decelerations and impact of measles on growth. Kasongo Project Team.

The occurrence of growth decelerations in children was studied in more than 16 000 two-to-four-month time intervals, ending at ages 6 through 59 months, during a multi-round survey in Kasongo. Decelerations were measured as changes in standard deviation scores which were compared with international and local weight-for-age, weight-for-height, arm-circumference-for-age and arm-circumference-for-height reference data. Decelerations were strikingly frequent, particularly at younger ages. An important number of decelerations was related to infection with measles which provokes initial wasting; later, recuperation was partly through increase of weight and arm circumference, and partly through delayed stunting. The measurement of growth decelerations has the advantage over isolated weight-for-age or arm-circumference-for-age measurements in that the impact of age-dependency-induced errors is largely eliminated. The relative merits of the local and international reference curves are discussed.

Child, Preschool↗
PubMed1975

A study of fetal heart rate deceleration areas. II. Correlation between deceleration areas and fetal pH during labor.

Three FHR deceleration areas of fixed durations related to the onset of the concomitant uterine contraction were evaluated automatically with a small digital computer during labor. The correlations between these areas and the fetal scalp blood pH values were studied. The deceleration occurring 80 to 140 seconds after the onset of each uterine contraction during the 20 minutes preceding the fetal blood sampling presented the best correlation (r equals minus 0.453) with fetal pH values. In addition to FHR deceleration area, baseline FHR variability should be considered in predicting fetal condition.

Apgar Score↗
PubMed1999

Analysis of blunt trauma injuries: vertical deceleration versus horizontal deceleration injuries.

There are several similarities found in blunt trauma injuries to humans sustained as a result of vertical deceleration (falling) and those sustained as a result of deceleration in a horizontal plane (automobile accidents). However, examination of the patterns of traumatic skeletal injuries can distinguish those injuries associated with falling from heights from those associated with automobile accidents. While there is considerable variation within each type of blunt trauma injury dependent on the angle at which one falls or is struck, there are several characteristic skeletal features associated with each type of trauma. In this study we review both the current literature and human skeletal remains from the University of New Mexico's Documented Collection known to have been subjected to blunt trauma. This collection is used to characterize and differentiate the pattern of skeletal injuries to various parts of the body for each type of trauma. These assessments are applied to investigate the traumatic skeletal lesions observed in a forensic case where the manner of death is unknown. Analyses suggest two possible scenarios that would explain the death of the individual investigated, with death most likely related to a vehicular-pedestrian accident.

Accidental Falls↗
PubMed2004

Decelerated medical education.

The aim of the study was to obtain information regarding the prevalence, structure, student characteristics and outcomes of formal decelerated medical education programs. A 13-item survey was mailed to all US medical schools examining characteristics of decelerated curricular programs. Responses were received from 77 schools (62% response). Some 24 (31%) indicated a formal decelerated option; 13 (57%) decelerate the first year while four (17%) decelerate year 1 or year 2. Participants may be selected before matriculation or after difficulty in 14 (61%) programs while four (17%) select only after encountering difficulty. Students may unilaterally choose deceleration in 10 (43%); 4.3% (0.1-12) of total matriculants were decelerated. The proportion of decelerated students identified as underrepresented minority (URM) was 37% (0-100), representing 10.5% (0-43) of total URM enrollment. Twelve (52%) programs do not provide unique support beyond deceleration. Standards for advancement are identical for decelerated and regular students in 17 schools (81%). In total, 10% (0-100) of decelerated students were dismissed within the last five years, representing 24% (0-90) of all dismissals. Few schools provided grade point average (GPA) or Medical College Admissions Test (MCAT) data but the limited responses indicate that many decelerated students are at risk for academic difficulty. It is concluded that decelerated curricular options are available at a significant number of US medical schools. Decelerated students comprise a small proportion of total enrollment but URM matriculants represent a disproportionate share of participants. Decelerated programs appear to be successful as measured by dismissal rates if one accepts attrition which exceeds that for regular MD students. Variation in dismissal rates is difficult to interpret given the lack of GPA and MCAT data. One half of all programs offer no additional support activities beyond deceleration. More data are needed to determine the relative contribution of deceleration vs. other support measures to the advancement of students at academic risk.

Curriculum↗
PubMed2003

Different types of variable decelerations and their effects to neonatal outcome.

OBJECTIVE: Although the only objective finding of intrapartum fetal distress is obtained through the measurement the fetal scalp pH, this invasive procedure is not available in every institution. The careful examination of fetal heart rate tracings for abnormalities, especially of the most commonly seen one, variable decelerations gains great importance under these circumstances. The aim of the present study is to determine the prognostic significance of variable decelerations in intrapartum fetal heart rate monitoring. METHODS: A total of 96 fetal heart rate tracings were analysed to assess the prognostic significance of variable decelerations. Sixty-six percent (64/96) of cases exhibited atypia characterised with (1) slow return of the fetal heart rate to the baseline; (2) loss of variability during the decelerations; (3) loss of initial and/or secondary accelerations; (4) persistence of secondary acceleration (overshoot); and (5) continuation of the baseline fetal heart rate at a lower level; (6) biphasic deceleration. One and five-minute Apgar scores and umbilical artery pH were used to assess the final fetal condition. RESULTS: Adverse fetal outcome characterised by fetal acidosis and Apgar score lower than 7 at one and five minutes were uncommon with pure variable decelerations. Typical and atypical variable decelerations were associated with low Apgar scores (< 7) at one minute in 9.3% and 54.6% of cases (p < 0.001) and at five minutes in 6.25% and 25% of cases (p < 0.05), respectively. In addition umbilical artery pH found to be lower than 7.2 in these cases ( 18.75% - p < 0.05). There was no danger for the fetal haemodynamic conditions when typical uterus contraction/variable deceleration ratios were two or more than two. However, risk of fetal hypoxia damage was quite high when this ratio was lower than two in atypical variable 5th minute low Apgar scores and pH (81.8% and 36.6% respectively). Atypical features are helpful in the identification of distress characterised by low Apgar scores in fetuses with variable decelerations. Admission to the neonatal intensive care unit was more common in patients with atypical variable decelerations in comparison with typical variable decelerations (34.3% versus 3.1%). CONCLUSION: While typical variable decelerations are frequently harmless, atypical variations pose a significant risk of fetal hypoxia.

Acidosis↗
PubMed1983

Intrapartum fetal heart rate monitoring. VIII. Atypical variable decelerations.

A total of 1,996 fetal heart rate (FHR) tracings were analyzed to assess the prognostic significance of variable decelerations. Nineteen percent (186 cases) of 988 tracings with variable decelerations in the last 30 minutes of monitored labor exhibited signs of atypia listed in order of frequency: (1) loss of initial acceleration, (2) slow return to the baseline FHR, (3) loss of secondary acceleration, (4) prolonged secondary acceleration, (5) biphasic deceleration, (6) loss of variability during deceleration, and (7) continuation of the baseline at a lower level. Variable decelerations with one or more of these features were called atypical variable decelerations and predicted a high incidence of fetal acidosis and low Apgar scores. By contrast, adverse fetal outcome was uncommon with pure variable decelerations (p much less than 0.001) irrespective of the duration and amplitude of the deceleration. Both pure and atypical variable decelerations were associated with other FHR abnormalities in over 60% of the cases. However, the particularly unfavorable combination with decreased FHR variability and tachycardia or bradycardia was seen more frequently with atypical than with pure variable decelerations (p much less than 0.001) and predicted the highest incidence of low Apgar scores. It is concluded that atypical features aid greatly in the identification of distress in fetuses with variable decelerations.

Apgar Score↗
PubMed1978

Clinical significance of fetal heart rate patterns during labor. V. Variable decelerations.

Among a large series of high-risk patients who had direct electronic monitoring, 330 fetuses presented "variable" decelerations and 598 had no decelerations. Among those with variable decelerations, there were 18 who presented such associated fetal heart rate (FHR) alterations as tachycardia, fixed baseline, and slow recovery ("hypoxic components"). The fetal outcome, as well as the characteristics of FHR patterns, were compared among the three groups. Baseline changes were significantly higher among pure variable decelerations and still higher among those having variable decelerations with hypoxic components. Likewise, one- and five-minute Apgar scores were significantly lower in that order. Only 4 per cent with no decelerations had clinical fetal distress while 23 per cent with variable decelerations and 78 per cent of those with variable and hypoxic components had distress. Neonatal death was higher among groups with variable decelerations. Premature rupture of membranes seemed to be the only clearly different (and probably influencing) clinical condition, being higher among the group with variable decelerations. Variable decelerations ("cord patterns") are associated with a relatively high rate of depressed infants. This problem is much worse when elements characteristic of hypoxia are identified in FHR tracings. The degree of drop in FHR frequency is not among those elements so identified. It is thus possible to prevent significant fetal deterioration by meticulous analysis of FHR tracings and active management when "late" components are identified on variable decelerations.

Electrocardiography↗
PubMed1981

Antepartum fetal heart rate monitoring. II. Deceleration patterns.

Fetal heart rate was studied during the antepartum period in 246 patients, yielding a total of 1964 recordings. The following parameters were evaluated and correlated: --the semi-quantitative assessment of fetal heart rate instability (as expressed by the percentage of duration of flat traces); --the presence of decelerations and their relationship to the presence or absence of uterine contractions; --the neonatal condition. Overall, 50% of the patients exhibited uterine contractions while 30% contained decelerations patterns either occurring spontaneously or in association with uterine contractions. A definite relationship was observed between the presence of severe decelerations (irrespective of the time relationship with any uterine contraction) and poor neonatal outcome. A relationship does exist between the presence of severe decelerations and flattening in the recording, which, as demonstrated in the previous part of the paper also exhibited a strong positive relationship with the neonatal outcome. When one considers the different degrees of flattening, it appears that a further correlation between decelerations and neonatal state is demonstrable only in the case of a 10--50% flat recording. Here the probability of a distressed baby is 20% in the absence of decelerations, but 43.4% in the presence of decelerations. In other cases (i.e., less than a 10% or more than a 50% flat recording) the pronostic significance of the instability of the record is not significantly modified by he presence or absence of decelerations. These results indicate that consideration of decelerations is only advisable in these cases where instability is moderately affected (flattening in 10-50% of the record) and that the use of the oxytocin challenge test OCT may be reserved for such cases, when these are neither spontaneous contractions nor decelerations and not contraindications present.

Apgar Score↗
PubMed1998

Significance of sporadic deceleration during antepartum testing in term pregnancies.

We have investigated the significance of single sporadic deceleration during reactive nonstress testing in normal pregnancies at term. A prospective study was performed during a 1-year period including 4742 nonstress tests performed between the 38th and 42nd weeks of pregnancy in patients referred to our department for antepartum testing and without any complication or pathology. Nonstress test (NST) was carried out with the patient lying on her left side, and was defined as reactive if at least two accelerations of 15 beats/min (bpm) or more lasting 15 sec were observed in a 20-min period. Sporadic deceleration was defined as a decrease in the fetal heart rate to less than 90 bpm or a decrease of 40 bpm below the baseline, lasting at least 2 min. The sporadic deceleration was considered as single when only one appeared in the first 20 min of monitoring and repeated when observed again once in at least one subsequent monitoring. Thirty-four cases of single sporadic deceleration were observed among women with reactive NST. In 14 cases there were repeated sporadic decelerations. The patients were divided into two groups according to the presence or absence of repeated decelerations. Outcomes of patients with repeated sporadic decelerations were compared with a group of 34 patients where sporadic decelerations were not observed during the antepartum testing. A significantly higher percentage of pathological fetal heart rate traces during labor were observed in the group of repeated decelerations. In conclusion the presence of repeated sporadic decelerations during a reactive NST suggests that the cause of cord compromise is persistent and recurrent cord compression is possible. Therefore, in these cases an increased fetal risk could be expected.

Adult↗
PubMed1994

The 'deceleration response' to transient perturbation of upright stance.

Characterizing the postural perturbation due to a transient support-surface displacement in terms of acceleration and deceleration events leads to a new framework for understanding the control of the stabilizing response. This study documents the existence of a 'deceleration response', which has not been reported previously, and explores the control of this response by varying the predictability of the timing and pattern of support-surface deceleration. Control features related to the capacity of the subject to predict deceleration were exposed, in part, by including novel 'tri-phasic' perturbations, in which the normal deceleration phase was replaced by a re-acceleration. In all trials, subjects showed a marked response to the onset of deceleration. The capacity of predict the timing and pattern of deceleration had a significant influence on the 'deceleration response', as well as the 'tonic' muscle activation that preceded the onset of deceleration.

Acceleration↗
PubMed2003

Non-invasive estimation of left ventricular end-diastolic pressure by pulmonary venous flow deceleration time.

AIMS: The scope of this study was to assess the potential value of pulmonary venous flow diastolic deceleration time to predict end-diastolic pressure and stratify patients with regard to elevation of left ventricular end-diastolic pressures. METHODS AND RESULTS: In 174 consecutive patients, pulmonary venous flow diastolic deceleration time was determined and compared with left ventricular end-diastolic pressures measured invasively. The sample was randomly divided into two subgroups of equal size for modelling of prediction and independent testing of the model. Predicted left ventricular end-diastolic pressures calculated from pulmonary venous flow diastolic deceleration time (left ventricular end-diastolic pressures=-10.87 + 5261/pulmonary venous flow diastolic deceleration time) agreed well with measured left ventricular end-diastolic pressures (mean difference: -1.3 +/- 3.4 mmHg). The correlation of left ventricular end-diastolic pressures with pulmonary venous flow diastolic deceleration time is fair (r=0.73989). A value of pulmonary venous flow diastolic deceleration time <220 ms is suggestive of elevated left ventricular end-diastolic pressures and should be monitored. A value of pulmonary venous flow diastolic deceleration time <190 ms predicts elevated left ventricular end-diastolic pressures. A value of pulmonary venous flow diastolic deceleration time <165 ms predicts severely elevated left ventricular end-diastolic pressures. With 190 ms as a cut-off value for elevated and 165 ms for severely elevated left ventricular end-diastolic pressures, cross-table analysis classifies all patients with normal left ventricular end-diastolic pressures correctly. No patient with severe elevation (<18 mmHg) of left ventricular end-diastolic pressures is classified as normal (chi2=102, P<0.0001). CONCLUSION: Pulmonary venous flow diastolic deceleration time is an appropriate non-invasive measurement to stratify patients with respect to elevation of left ventricular end-diastolic pressures.

Adult↗
PubMed1993

Large fetal heart rate decelerations at term associated with changes in fetal heart rate variation.

OBJECTIVE: The objective was to determine whether large antepartum decelerations in fetal heart rate were associated with a switch from high to low fetal heart rate variation, suggestive of a change in sleep state, and whether the variation predicted outcome. STUDY DESIGN: Retrospective computerized analysis of 10,272 cardiotocographic records from 3998 patients at 37 to 42 weeks' gestation from four centers in England and Italy identified 140 good-quality records with large decelerations (more than 20 lost beats in area). RESULTS: In otherwise normal cardiotocograms a large deceleration had a 40% chance of association with a downward change in fetal heart rate variation (69% when the deceleration exceeded 100 lost beats). The change resembled that occurring naturally with behavioral states. Uterine contractions did not always precede large decelerations. When they did, the lag time (peak of contraction-trough of deceleration) increased from 28 seconds (at 20 to 29 lost beats) to > 100 seconds with increase in deceleration area. Of patients with large decelerations 76% had a normal vaginal delivery. CONCLUSION: Large decelerations near term, present in up to 5% of patients with otherwise normal fetal heart rate and variation, are often associated with a fall in fetal heart rate variation characteristic of a change in sleep state, without ominous significance.

Female↗