Biomedical subjects

K A Kuhlman

Publications and source records attributed to K A Kuhlman.

3 recordsLinked to original sources

PubMed1991

Doppler evaluation of umbilical and uterine-arcuate arteries in the postdates pregnancy.

To assess the correlation between Doppler velocimetry and perinatal outcome in the postdates pregnancy, 75 women who were at least 41 weeks' gestation were evaluated twice weekly until delivery. Evaluation included Doppler velocimetry of the umbilical and uterine-arcuate arteries, as well as nonstress testing and amniotic fluid volume estimation. The mean umbilical artery systolic-diastolic ratio (S/D) was significantly higher in the pregnancies with subsequent abnormal perinatal outcomes than in those with normal outcomes (2.42 versus 2.19; P = .03). Using a receiver operating characteristic curve, an abnormal umbilical artery S/D was defined as 2.40 or greater. Using this value, sensitivity was 57.1% and specificity was 77.8%. Our study suggests that an umbilical artery S/D of 2.40, rather than the more traditionally accepted cutoff of 3.0, may be a useful threshold to identify those postdates pregnancies at high risk for abnormal perinatal outcome.

Adult↗

PubMed1988

Ultrasonic imaging of normal fetal response to external vibratory acoustic stimulation.

Fetal facial reactions and response decrement patterns to external noise stimulation were studied to characterize normal fetal neurobehavior in the third trimester. Response decrement, or habituation, is thought to reflect higher central nervous system function. Two hundred women with uncomplicated pregnancies, who were subsequently delivered of healthy infants at term, were studied between 26 and 41 weeks' gestation. After ultrasound views of the fetal face were obtained, a vibratory acoustic stimulus was applied repetitively to the maternal abdomen near the fetal head. Response decrement was defined as cessation of all components of the facial reaction, except eye blinking, over two sequential stimuli. Three response patterns were scored: (1) no startle, (2) startle without response decrement, and (3) response decrement by 12 stimuli. Whereas only 53% of fetuses between 26 and 27 weeks displayed startle reaction, all fetuses displayed startle responses by 28 weeks. As gestational age advances, an increasing number of fetuses exhibit response decrement, from no decrement at 26 to 27 weeks to 100% decrement at 40 to 41 weeks. A maturation of neurobehavioral response patterns takes place in normal third-trimester pregnancies. Response decrement testing may be a useful tool for in utero neurologic evaluation.

Acoustic Stimulation↗

PubMed1988

Acoustic stimulation testing.

The nonstress test is the most widely employed method of fetal health assessment. The current approach is to use the OCT or biophysical profile as a means of identifying the fetus at very high risk should the nonstress test be either nonreassuring or equivocal. The acoustic stimulation test may have a predictive ability similar to that of the biophysical profile and thus may be used to complement nonstress testing as early as 28 weeks' gestation. It reliably invokes a reactive NST in those fetuses destined to demonstrate reactivity with persistence in monitoring and facilitates more rapid and efficient testing. The acoustic test may have the additional benefit of providing a screening mechanism for anomalies in which neurologic performance is suboptimal. However, because the test has not been studied on large numbers of patients and because different applications of such stimuli may elicit differing responses, its adaptation for clinical use should be cautious at the present time.

Acoustic Stimulation↗