Ultrasound Technologies Fetatrack 310, Service Manual

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Ultrasound Technologies Ltd
Operating Procedures
Fetatrack310 Service Manual Issue3 Page 9
©Ultrasound Technologies Ltd, Lodge Way, Portskewett, Caldicot, South Wales NP26 5PS, United Kingdom.
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www.doppler.co.uk
Ultrasound Fetal Monitoring
The FETATRACK 310 ultrasound transducer is used to detect and monitor the fetal heart
beat. The FETATRACK 310 can monitor twins and if this option is chosen it is supplied
with two Ultrasound transducers. The primary Ultrasound Transducer (always supplied )
has a yellow coded plug while the twin channel has a blue coded plug. Push the relevant
plug firmly into is colour coded front panel US socket and turn the unit on.
Locate a clear fetal heart sound using a Doppler Fetal Heart Detector and secure the
stretch belt in position, so that it passes over the transducer site, and clamp in place by
fastening the buckle after feeding the belt through the transducer.
Apply gel to the surface of the transducer locating it approximately in the position
determined by the Doppler detector. Position the transducer to obtain the clearest fetal
heart sound. The heart rate processor will start to calculate heart rate within a few
seconds and the heart rate can be observed on the LCD display. Correct operation
can be verified by observing that the pulse lamp is flashing at the heart rate.
The heart shaped fetal pulse indicator is also used as a signal quality indicator.
When positioning the transducer observe the indicator, which should be solid under the
best signal conditions. If this indicator is only showing an outline heart then this is an
indication that the signal quality is not optimum. Improved recordings can be
obtained by repositioning the transducer so that this indicator always shows a solid
heart. In the absence of signals of adequate quality this indicator will be permanently off.
The audio volume can be increased by pressing the volume up button marked with the
up arrow. Conversely to decrease audio volume press the button marked with the down
arrow. In twins mode the audio output is selected for either channel by pressing the US
1/2 button. The selected channel is indicated on the LCD display by the capital US letters.
Once a clear fetal heart signal has been located set the volume to the desired level
using these controls.
Transducer position should be checked at least half-hourly during labour-monitoring or
prolonged NST. When repositioning the transducer, further coupling gel may be
required When repositioning the transducers always ensure that the fetal pulse indicates
the optimum signal conditions.
Results will vary from one patient to another, but in all cases good transducer
positioning is essential, and this may be aided by the use of a liberal amount of coupling
gel.
With the fetus in the vertex presentation, and the mother sitting or supine, the clearest
sound will normally be found on the midline below the umbilicus. In the lateral
position, clearer sounds may be found with the transducer displaced from the centre line
to the upper surface of the abdomen. The clearest signals in breach presentation may
be located higher and to one side.