GE Corometrics 172 - Tocotransducer (External Method); Methodology; Establishing a Baseline

6-2 170 Series Monitor Revision D
2003023-001
Uterine Activity Monitoring: Tocotransducer (External Method)
Tocotransducer (External Method)
Methodology
A tocotransducer applied to the maternal abdomen records relative changes in
abdominal tension caused by uterine contractions. The value is displayed in relative
units from 0–100. Uterine activity is continuously plotted on the bottom (or right) of
the strip chart paper as a plain black line.
GE Medical Systems Information Technologies offers two models of
tocotransducers: Nautilus and Trimline. Each model is available in a loop-style and
button-style. Both styles are discussed in the “Maternal/Fetal Monitoring
Operator’s Manual”.
IMPORTANT
FOR TRIMLINE TOCOTRANSDUCERS ONLY—You must
wait at least ten seconds from the time you power the monitor on
or connect a tocotransducer before pressing the
UA Reference
button.
Establishing a Baseline
Monitoring uterine activity using a tocotransducer provides relative pressure
measurements—compared to a baseline or UA reference. The quality of
measurements depends on the following:
 position of the tocotransducer;
 belt tension;
 size of the patient; and
 established baseline.
All 170 Series Monitors provide a UA Reference button which sets the baseline.
When a baseline is established, all pressure measurements are relative to that
baseline. The baseline can be set manually by two different methods or
automatically, when necessary. Whenever the baseline is set, the bottom line of the
bottom strip chart grid is annotated with
.
UA
REF