The document discusses electronic and manual assessment of uterine contractions through tocodymanometry, intrauterine pressure catheters, and palpation. Tocodymanometry is used to assess contraction frequency and duration while palpation determines intensity. Intrauterine pressure catheters directly measure pressure in mmHg. Normal contractions are bell-shaped while tachysystole is defined as more than 5 contractions in 10 minutes over 30 minutes. If tachysystole develops with a reassuring fetal heart rate, interventions like position changes and IV fluids are implemented.

1. Assessment of Uterine
Contractions
August 2011
Inpatient Review Course
Sandy Warner RNC-OB, MSN

2. Electronic Assessment of Uterine
Contractions
 Electronic assessment monitoring of
Contractions is done with:
 Tocodynamometer when placed on upper portion
of uterus frequency and duration of contractions
can be determined
 Intrauterine pressure catheter (IUPC) catheter
placed in uterus measures pressures in the uterus
before during and after contraction is over in
mmHg. Palpation between contractions still
necessary.

3. Timing Contractions: Frequency, Duration
& Intensity
 To assess (time) frequency of UC
 beginning of one contraction until beginning of
next contraction
 To assess duration
 from beginning of contraction until end of
contraction
 To assess intensity
 palpate fundus of uterus to determine firmness of
contraction

4. Tracing of Uterine Activity
frequency
Intensity
duration
Relaxation
TOCO placed on upper part of uterus to assess frequency
and duration of contractions. Palpation done to determine intensity
And relaxation.

5. Timing Contractions:
Uterine Resting Tone
 To assess relaxation
Palpate fundus of uterus (between UC). Uterus should be
very relaxed (soft). If not soft, then not relaxed. Between
UC is when fetus gets blood through spiral arteries of
uterus. Resting tone palpation needs to be done with
either external or internal UC monitoring

6. Assessment – Uterine Contractions by
Palpation
 Contraction  Corresponds to Palpation of
Intensity Body Part
 Mild  Tip of nose
 Moderate  Chin
 Strong  Forehead
Place hand on fundus of uterus to assess uterine contractions. Keep hand on fundus throughout
several contractions to determine difference between relaxation and contraction increasing
in intensity to peak and then decreasing in intensity to relaxation. Use key above.
Malinowski, 1989 6

7. Intrauterine Pressure Catheter
 Requires ROM  More accurate due to
 Pressure of direct measurement of
contractions measured intrauterine pressure
in mm Hg
 Provides measurement
of strength of UC
 Notation must be made
of resting tone (should
be below 20 mm Hg)
 Can be re-zeroed if
baseline increases

8. Terminology for Describing Uterine
Activity
 Normal
 Hypotonus and Hypertonus
 Multiphasic – dysfunctional
 Tachysystole

9. Normal, Hypotonic & Hypertonic Contractions
Bell shaped
Weak contraction
Uncoordinated contraction pattern

10. Uterine Hypertonus
Hypertonus - insufficient relaxation between contractions.
Uterus not soft between contractions
If IUPC in place pressure between UC is ≤ 20-25 mmHg.

11. Multiphasic Contractions – (coupling or tripling)
- may be caused by over saturation of uterine oxytocin
receptor sites

12. Tachysystole
 > 5 in 10 minutes contractions averaged over a 30
minute window
 Always in relation to the presence or absence of
decelerations.
 Applies to both spontaneous or stimulated labor
 Interventions MUST be performed AND documented
 Appropriate management of pitocin is essential

13. Tachysystole

14. Administer Oxytocin drip as ordered by Primary Care Provider to achieve cervical
dilation and adequate contraction pattern while maintaining a normal Fetal Heart
Rate pattern.
If Tachysystole develops:
Contractions lasting > 2 minutes over a 10 minute period
or
>5 (6 or more) Contractions in 10 minutes averaged over a 30 minute period
or
Contractions occurring within 1 minute of each other over a 10 minute period
Is the FHR reassuring?
(Moderate variability and absence of recurrent late/variable decelerations)
YES NO
Category I Category II / III
(Reassuring FHR Tracing) (Indeterminate/Abnormal FHR Tracing)
Continue to observe for approximately 30 Discontinue the Oxytocin administration
minutes as long as FHR is reassuring Notify the provider and document report
Consider the following interventions: and interventions used to resolve the
Maternal position change clinical situation
IV Fluid hydration Interventions:
Increased frequency of observation Maternal position change
Document and report interventions IVF bolus
Oxygen at 10-12 Lpm
Increased frequency of observation
Did Uterine Tachysystole resolve? Document and report interventions
YES NO
Continue Decrease the Pitocin by Observe for 10-30 minutes, Pitocin
increasing ½. Continue to observe may be restarted at ½ the previous
Pitocin as for an additional 30 dose if FHR is reassuring and
ordered minutes providing the uterine activity is inadequate
FHR remains reassuring Consider IUPC placement
If uterine Tachysystole If uterine Tachysystole reoccurs,
does not resolve after 60 notify provider
minutes, notify the
provider