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PubMed1996

Decelerating gastric emptying: therapeutic possibilities in type 2 diabetes.

There is clear evidence of a positive correlation between carbohydrate absorption, plasma concentration of glucose, and the rate of gastric emptying. This suggests that clinical manipulation of gastric emptying rates may have therapeutic potential in glycaemic control. Cholecystokinin (CCK-8) has been shown to delay gastric emptying in individuals with Type 2 diabetes, but its potential as a therapy is limited by the need to administer it intravenously. The preferred routes of administration would be intramuscular injections, an intranasal spray or the use of orally ingested CCK analogues. Alternatively, the oral administration of an agent that enhances endogenous release of CCK could represent an important approach to the treatment of Type 2 diabetes. Agents such as POT II may have a therapeutic indication in patients with recently diagnosed Type 2 diabetes.

Blood Glucose↗
PubMed2001

Late second-trimester nonstress test characteristics in preterm delivery before 32 weeks of gestation.

OBJECTIVE: To clarify electronic fetal heart rate (FHR) monitoring characteristics in pregnancies with preterm delivery before 32 weeks of gestation, using the late second-trimester nonstress test. METHODS: Among 953 children born from 1993 to 1996, we identified 100 singleton infants born before 32 weeks of gestation in whom second-trimester (24-27 weeks of gestation) electronic fetal monitoring (EFM) records were obtained. Individual components of the FHR patterns [baseline rate, baseline FHR variability, presence of acceleration (at least 10 beats/min for at least 10 s) and periodic or episodic deceleration (at least 25 beats/min for at least 15 s)] and birth characteristics were compared between pregnancy with or without second-trimester decelerations. RESULTS: Among 100 infants, 65 had and 35 did not have second-trimester decelerations. There were no significant differences in gestational age at birth, birth weight, cord arterial blood pH, Apgar score and meconium staining between pregnancies with second-trimester decelerations and those without second-trimester decelerations. There were no significant differences in baseline rate and baseline variability between pregnancies with or without second-trimester decelerations. The number of accelerations in pregnancies with second-trimester decelerations was significantly more frequent than that in pregnancies without second-trimester decelerations (p < 0.001). There was a significant increase in the occurrence of premature rupture of the membranes (PROM; 60.0%) in pregnancies with second-trimester decelerations, when compared with events (37.1%) related to pregnancies without second-trimester decelerations (p < 0.05). There were no significant differences in the onset of breech presentation, cervical incompetency, preeclampsia and abnormal FHR pattern at birth between pregnancies with second-trimester decelerations and those without second-trimester decelerations. Pregnancies with PROM after second-trimester EFM were significantly more likely to have second-trimester decelerations than those without PROM (75.0 vs. 54.2%, p < 0.05). CONCLUSION: Periodic or episodic decelerations during late second-trimester EFM were associated with an increased risk of the occurrence of PROM in pregnancies with preterm delivery before 32 weeks of gestation.

Adult↗
PubMed2001

Is intrapartum vibroacoustic stimulation an effective predictor of fetal acidosis?

OBJECTIVE: The hypothesis of this prospective study is that intrapartum vibroacoustic stimulation (VAS) is an effective predictor of fetal acidosis during labor. Various clinical conditions, such as term versus preterm gestation, first stage versus second stage of labor, and fetal heart rate (FHR) variable decelerations versus late decelerations will be tested. METHODS: During the study period, 113 patients were studied prospectively in either active phase of first stage (n = 53) or during the second stage of labor (n = 60). They were selected from cases exhibiting moderate to severe FHR variable decelerations or late decelerations. The fetuses of study subjects received a VAS for three seconds and FHR changes were recorded. Fetal scalp blood pH or umbilical arterial blood pH was obtained within 15 minutes of VAS. The relationship between FHR responses to VAS and fetal blood pH in term and preterm gestations, the relationship of two tests (VAS and fetal blood pH) to type of FHR decelerations, and the predictability of neonatal morbidity by two tests were analyzed. Where appropriate, Fisher's exact test (p < 0.05 was considered statistically different) and the odd ratio with 95% confidence intervals were used for statistical analyses. RESULTS: Excellent association between acceleration response to VAS and pH > or = 7.20, and between a negative response to VAS (no acceleration or decelerations) and pH < 7.20 were found in the first stage of labor, the second stage of labor, and the combination of both stages together (p = 0.0001, OR = 10.6 [3.3-34.0]). It was observed that negative VAS responses for predicting fetal acidosis (pH < 7.20) were comparable between term (> or = 37 weeks) and preterm (< 37 weeks, > or = 34 weeks) fetuses. Since the preterm fetuses enrolled in the study were limited in number, it is difficult to draw adequate conclusions. The positive predictive value (PPV) of fetal acidosis was 67% in both groups of FHR variable decelerations and late decelerations, but the false negative rate of acceleration VAS response for predicting no acidosis was significantly higher in the group of late decelerations (29% vs 8%, p = 0.034). Finally, both a negative VAS response and fetal acidosis (pH < 7.20) have equal predictability for neonatal morbidity. The PPV of NICU admission by a negative VAS response was two times higher than that of fetal acidosis (PPV = 61% vs 29%, p = 0.038). CONCLUSION: We found that intrapartum VAS was an effective predictor of fetal acidosis in cases of FHR variable decelerations, but its predictability for fetal acidosis in cases of FHR late decelerations was limited. Both VAS and fetal blood pH are good predictors of neonatal morbidity.

Acidosis↗
PubMed1975

[The clinical importance of abnormal heart rate tracings during labour (author's transl)].

A continuous fetal heart rate tracing of the first and second stage of labour was available for 221 labours and deliveries with varying histories of the present pregnancy. The importance of the abnormalities of the fetal heart rate in these tracings was interpreted in comparison to the development of fetal acidosis. There were no cases of fetal acidosis when changes of the basal frequency occured as an isolated phenomenon independant of the oscillation type. Variable decelerations without silent oscillation of loss of oscillation at the low of the deceleration led to a slight increase of fetal acidosis only after 10 decelerations. Late or combined decelerations were associated with fetal acidosis in 25% of the cases. The incidence of acidosis increase with the increase in the number of decelerations. According to our results the loss of oscillation at the low of the deceleration is of very great importance. Without loss of oscillation at the low of deceleration only 7.2% of the pH values were below normal whereas after 1 to 5 such losses of ascillation already 23.5% of the pH values were below normal. Following more than 10 decelerations with loss of oscillation 75% of the fetuses showed an acidosis. The first abnormal pH values were detectable not earlier than 20 minutes after the first sign of variable, late or combined decelerations in the cardiotocogram. Decelerations in combination with silent oscillation of the basal frequently or loss of fluctuation at the low of the deceleration were associated with fetal acidosis in 50% of the cases. Indications for fetal skalp blood sampling or termination of the labour were proposed in the light of our results.

Acidosis, Respiratory↗
PubMed2004

Intrapartum fetal heart rate monitoring in cases of cytomegalovirus infection.

OBJECTIVE: Several studies have shown that abnormal intrapartum fetal heart rate patterns are the results from pre-existing fetal brain damage. We evaluated intrapartum fetal heart rate pattern of cytomegalovirus-infected fetuses and correlated the patterns with neurologic outcomes. STUDY DESIGN: Between 1991 and 2001, there were 20 cytomegalovirus-infected fetuses. We selected 40 fetuses as control subjects that were matched for gestational age and birth weight. Fetal heart rate was interpreted according to the guidelines of the National Institute for Child and Human Development. The incidence of abnormal fetal heart rate pattern and umbilical blood gases were compared between both groups. We also investigated the factors that contributed to abnormal fetal heart rate pattern in the cytomegalovirus group. RESULTS: Nonreassuring fetal heart rate patterns (prolonged deceleration and recurrent late deceleration) were observed in 8 of 20 fetuses (prolonged deceleration, 7 fetuses; recurrent late deceleration, 1 fetus) in the cytomegalovirus group and in 3 of 41 fetuses (prolonged deceleration, 1 fetus; recurrent late deceleration, 2 fetuses) in the control group (P<.05, Fisher test). Baseline fetal heart rate variability was minimal in 4 of the 7 prolonged deceleration cases in the cytomegalovirus group. Umbilical pH <7.1 was found for 1 fetus in the cytomegalovirus group. The average umbilical arterial pH values were similar in both the groups. In the cytomegalovirus group, there were no differences in the incidence of contributing factors between 8 fetuses with abnormal fetal heart rate pattern (prolonged deceleration and recurrent late deceleration) and 8 fetuses with no change. There were 3 fetuses with cerebral palsy: 2 fetuses in the no change group and 1 fetus in the prolonged deceleration group. Antigenemia was positive exclusively in 4 cases with abnormal fetal heart rate pattern (P<.05). CONCLUSION: Cytomegalovirus-infected fetuses are more likely to show abnormal intrapartum fetal heart rate patterns than low-risk control fetuses, which suggests that the perinatal detection of cytomegalovirus is necessary to distinguish hypoxic-ischemic encephalopathy.

Cerebral Palsy↗
PubMed2002

[Predictive value of umbilical artery lactate levels and fetal heart rate monitoring for fetal distress].

OBJECTIVE: Measuring umbilical artery lactate levels to evaluating the predictive value of abnormal fetal heart rate (FHR) monitoring patterns for fetal distress. METHODS: There were 73 neonates with abnormal fetal heart monitoring patterns in the distress group. The abnormal patterns included abnormal baseline FHR, severe variable decelerations, mild variable decelerations and tachycardia. There were 118 normal neonates (Apgar score > or = 9) in the control group. Twenty min fetal heart monitoring was performed at the time of admitting, laboring and in labor and in active phase. Continuous fetal heart monitoring was performed during the second stage of labor. All neonatal umbilical artery lactate levels were measured at delivery. RESULTS: The rate of using forceps in distress group was significantly higher than that of the control (P < 0.01), the rate of spontaneous labor was significantly lower than the control group (P < 0.01). In the distress group, severe variable decelerations were generally emerged in the second stage of labor. The incidence of neonatal Apgar score < or = 7 in neonates with abnormal baseline FHR was higher than those with severe variable decelerations, mild variable decelerations and tachycardia (P < 0.05). As for neonatal umbilical artery lactate levels, the neonatatuses with abnormal baseline FHR was (4.55 +/- 0.23) mmol/L, the neonatatuses with severe variable decelerations was (3.84 +/- 0.40) mmol/L, all significantly higher than the control group's (P < 0.01). The neonatatuses with mild variable decelerations was (2.63 +/- 0.32) mmol/L, the neonatatuses with tachycardia was (2.55 +/- 0.46) mmol/L, and there are no significant differences between the neonatatuses with mild variable decelerations and tachycardia and the control group's (P > 0.05). CONCLUSIONS: Measuring umbilical artery lactate levels is an efficient and accurate technique for fetal distress diagnosis. There was a close correlation between baseline FHR with abnormal changes and severe variable deceleration with fetal distress. There was no certainly correlation between mild variable decelerations and tachycardia with fetal distress. It should be evaluated later.

Female↗
PubMed1991

Diagnosis and management of intrapartum fetal distress.

Fetal distress is a frequent reason for obstetric intervention during labour. The final diagnosis generally is based upon the information in the cardiotocographic tracings, whether or not combined with the information from fetal scalp blood sampling. Reading, classification and interpretation of fetal heart rate (FHR) recordings is subject to considerable interobserver variation, even among experienced obstetricians. Far too often, individual decelerations in the heart rate are classified as early or late, merely on the basis of the relationship between the decelerations and the accompanying contraction. Hon's original flow sheet for classification of decelerations dictates assessment of the full tracing with, as a primary step: are decelerations uniform or not? Non-uniform decelerations should automatically be classified as variable. Comparison between the onset of the deceleration and the uterine contraction curve is the second step. Variable decelerations are the predominant type in the majority of intrapartum recordings. Features in the FHR rhythm to be assessed in case of variable decelerations include assessment of the baseline level, presence or absence of accelerations, variability in the baseline pattern and during the decelerative part of the tracing, initial and secondary acceleration, overshoot following the deceleration whether or not with smoothing, recovery from the deceleration, continuation of the baseline level and the time intervals between contractions or recurrent efforts of pushing activity. The paper further addresses pathophysiologic mechanisms of fetal distress, maternal and fetal risk factors and various alternatives in the management of intrapartum distress.

Female↗
PubMed1991

Effects of mental exercise in patients with dilated cardiomyopathy and congestive heart failure. An echocardiographic Doppler study.

To assess the effects of mental stress on left ventricular diastolic function in patients with congestive heart failure, nine patients aged 57 +/- 12 years with dilated cardiomyopathy (end-diastolic volume, more than 110 ml/m2; ejection fraction, less than 40%; mean, 28 +/- 8%) and congestive heart failure in New York Heart Association functional class II or III and 14 normal volunteers (mean age, 49 +/- 8 years) were studied during mental arithmetic lasting 10 minutes with echocardiographic Doppler monitoring of transmitral flow velocity. During mental arithmetic, the ratio of peak flow velocity in early versus late diastole (E/A) and deceleration time of early diastole did not change in normal controls. However, E/A increased significantly (from 1.6 +/- 1.5 to 1.9 +/- 1.7; p less than 0.01) and deceleration time markedly decreased (from 156 +/- 49 to 108 +/- 31 msec; p less than 0.001) in patients with congestive heart failure. In 16 postinfarct patients with ejection fraction of less than 40% studied during mental arithmetic with simultaneous hemodynamics and Doppler recordings, good correlations were found between pulmonary wedge pressure and Doppler parameters (wedge pressure versus E/A, r = 0.89; wedge pressure versus deceleration time, r = -0.87). During mental arithmetic, the pulmonary wedge pressure-E/A correlation was weaker (r = 0.67), whereas the correlation between pulmonary wedge pressure and deceleration time was stronger (r = 0.91). The value of 153 msec in deceleration time was the best cutoff point in predicting 12 mm Hg pulmonary wedge pressure, both at rest and during mental arithmetic: the higher the deceleration time, the lower the pulmonary wedge pressure, and vice versa. Among patients with congestive heart failure, five showed normal baseline deceleration time (195 +/- 21 msec; pattern 1), and the remaining four showed a short (less than 153 msec) deceleration time (108 +/- 13 msec; pattern 2). During mental arithmetic, deceleration time markedly decreased to as short as 119 +/- 20 msec in all patients except one with baseline pattern 1. Deceleration time further decreased to 75 +/- 6 msec in all patients with baseline pattern 2. Mental arithmetic induces changes in left ventricular diastolic function in patients with congestive heart failure. Transmitral echocardiographic Doppler provides a simple noninvasive method of estimating and monitoring pulmonary wedge pressure in patients with severe left ventricular dysfunction.

Cardiomyopathy, Dilated↗
PubMed1999

Comparison of late-second-trimester nonstress test characteristics between small for gestational age and appropriate for gestational age infants.

OBJECTIVE: To compare electronic fetal heart rate (FHR) monitoring characteristics between appropriate for gestational age (AGA) fetuses and small for gestational age (SGA) fetuses and to determine whether SGA fetuses have specific abnormalities at second-trimester electronic fetal monitoring (EFM), using nonstress test. METHODS: Among 953 children born from 1993-1996, we identified 500 singleton infants born after 36 weeks' gestation of uncomplicated pregnancies in whom second-trimester (24-27 weeks' gestation) EFM records were obtained. Individual components of FHR patterns (baseline rate, baseline FHR variability, presence of acceleration [at least 10 beats per minute for at least 10 seconds], and periodic or episodic deceleration [at least 25 beats per minute for at least 15 seconds]) and birth characteristics were compared between AGA and SGA infants, or between pregnancies with or without second-trimester decelerations. RESULTS: Among 500 infants, 443 were AGA and 57 SGA; 105 had and 395 did not have second-trimester decelerations. Baseline FHR variability (12.9+/-3.2 beats per minute) in SGA fetuses was significantly higher than variability (10.3+/-3.4 beats per minute) in AGA fetuses (P<.001). Small for gestational age fetuses were significantly more likely to have second-trimester decelerations than AGA fetuses (33.3% vs. 19.4%, P<.05). There were no significant differences in baseline rate and accelerations between AGA and SGA infants. Small for gestational age infants were more frequent in pregnancies with second-trimester decelerations, compared with those without second-trimester decelerations (18.1% vs. 9.6%, P<.05). Baseline FHR variability in pregnancies with second-trimester decelerations was significantly higher than in pregnancies without second-trimester decelerations (12.2+/-3.7 vs. 10.0+/-3.1 beats per minute, P<.001). CONCLUSION: Periodic or episodic decelerations and increased FHR variability during late second-trimester EFM were associated with an increased risk of SGA birth weight.

Cardiotocography↗
PubMed2005

Braking of elbow extension in fast overarm throws made by skilled and unskilled subjects.

A previous computer simulation study of overarm throws in 2D showed that reversal of elbow torque by antagonist muscle action late in the throw led to increased wrist flexion velocity and to increased ball speeds. We tested the hypothesis that the skill of making fast overarm throws in 3D involves deceleration (braking) of elbow extension before ball release, and that this is an active mechanism. Skilled and unskilled throwers were instructed to throw baseballs at a fast speed. Arm segment angular positions in 3D at 1,000 Hz were recorded with the search-coil technique (which records angular motions). In skilled throws, but not in unskilled throws, there was a period (mean 17 ms) of rapid elbow extension deceleration before ball release. However, there was relatively little biceps EMG activity associated with the very large magnitude of elbow deceleration. This finding and other work suggests that elbow extension deceleration results in part from interaction torques associated with late-occurring shoulder rotations, and only in part from elbow flexor contraction. During the period when elbow extension was decelerating, the forearm in space was undergoing angular acceleration (because of internal rotation at the shoulder) which would be expected to produce a torque at the wrist in the extensor (not flexor) direction. The results show that elbow extension deceleration occurs before ball release in fast (skilled) 3D throws, and that it does not produce forearm angular deceleration. Whether it produces forearm translational deceleration, which could increase wrist flexion velocity, remains to be determined.

Adult↗
PubMed1988

Comparison of Doppler echocardiographic and hemodynamic indexes of left ventricular diastolic properties in coronary artery disease.

Transmitral flow velocity was measured by Doppler echocardiography in 15 patients with coronary artery disease simultaneously with high-fidelity recording of left ventricular pressure. Doppler echocardiographic recordings were also performed in 14 age- and heart rate-matched normal subjects. Statistically significant differences (p less than 0.05) in acceleration half-time (55.3 +/- 8.2 vs 70.4 +/- 14.9 ms), deceleration half-time (83.1 +/- 17.9 vs 109.5 +/- 18.1 ms), deceleration rate (4.9 +/- 0.9 vs 3.1 +/- 0.9 m/s2), peak velocity of early diastolic left ventricular inflow (E wave) (0.78 +/- 0.13 vs 0.61 +/- 0.13 m/s) and A/E ratio (0.74 +/- 0.20 vs 0.98 +/- 0.31) between normal subjects and patients were noted. There was no significant difference in peak velocity of atrial systolic flow (A wave) between normal subjects and patients. Correlation between transmitral flow indexes and hemodynamic indexes of left ventricular diastolic properties were poor, with r values ranging from 0.02 to 0.65. Significant correlations between deceleration rate versus maximal isovolumic left ventricular pressure decrease (maximum -dP/dt) and A wave versus maximum -dP/dt (p less than 0.05) were found (0.53 and 0.65, respectively). Deceleration rate was the most sensitive index of isovolumic relaxation assessed by hemodynamic methods, whereas the A/E ratio was a poor indicator of hemodynamic measurements of isovolumic relaxation. An abnormal deceleration rate had 100% specificity for detecting abnormal maximum -dP/dt, while abnormal acceleration half-time, deceleration half-time and A/E ratio had 80% specificity for detecting abnormal time constant. The deceleration rate, acceleration half-time, deceleration half-time and A/E ratio had a predictive value of 60 to 100% for the detection of abnormal maximum -dP/dt and time constant.

Adult↗
PubMed1977

Intrapartum fetal heart rate profiles with and without fetal asphyxia.

Fetal heart rate profiles for periods up to 12 hours prior to delivery have been reviewed in 515 patients with a fetus at risk. Mechanisms other than fetal asphyxia will cause fetal heart rate decelerations, and fetal asphyxia may in some instances develop in the absence of total or late decelerations. However, an increasing incidence of total decelerations and late decelerations and particularly a marked pattern of total decelerations and late decelerations are of value in the prediction of fetal asphyxia. Fetal heart rate deceleration patterns can predict the probability of fetal asphyxia at the time of initial intervention, while a progression of fetal heart rate deceleration patterns in the individual fetus can be of assistance in the subsequent scheduling of serial acid-base assessments during labor.

Asphyxia↗