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Published on: February 18, 2012
Vibroacoustic Stimulation of the Fetus Using a Conventional Mechanical Alarm Clock
1Department of Obstetrics and Gynecology, Innsbruck University, Innsbruck, Austria
Journal of Maternal-Fetal Investigation : the Official Journal of French Society of Ultrasound in Medicine and Biology ... [Et Al.]
|May 18, 1999
Summary
A standard wind-up alarm clock is an effective and inexpensive alternative for vibroacoustic stimulation testing (VAST) in fetuses with low heart rate variability. This method safely stimulates fetal heart rate acceleration and movement patterns.
Area of Science:
- Obstetrics and Gynecology
- Fetal Monitoring
- Bioacoustics
Background:
- Vibroacoustic stimulation testing (VAST) is crucial for managing fetal heart rate patterns with low variability.
- The artificial larynx is a common VAST tool, but other devices require proper evaluation.
Purpose of the Study:
- To evaluate the efficacy of standard mechanical wind-up alarm clocks for VAST.
- To compare different alarm clock placements and the use of ultrasound gel for VAST effectiveness.
Main Methods:
- VAST using an alarm clock was performed on 80 pregnant women (36 weeks to term).
- Tested alarm clock placement (fetal head vs. contralateral side) and use of ultrasound gel.
- Investigated effects on fetal heart rate, variability, and movement patterns using kineto-cardiotocography (K-CTG).
Main Results:
- All fetuses exhibited heart rate acceleration, increased variability, and movement post-VAST.
- No significant difference in fetal response based on alarm clock placement or gel use.
- K-CTG agreement with perceived movements depended on patient visibility of the tracing.
Conclusions:
- A conventional wind-up alarm clock is a safe, inexpensive, and effective VAST alternative.
- It adheres to the ALARA (As Low As Reasonably Achievable) principle.
- This method can be a practical tool in fetal well-being assessments.
