Assessment of Uterine ContractionsAugust 2011

Inpatient Review Course

Sandy Warner RNC-OB, MSN

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.

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

Tracing of Uterine Activity

Relaxation

Intensity

TOCO placed on upper part of uterus to assess frequency and duration of contractions. Palpation done to determine intensity And relaxation. .

duration

frequency

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

Malinowski, 1989 6

Assessment – Uterine Contractions by Palpation

Contraction

Intensity

Mild Moderate Strong

Corresponds to Palpation of

Body Part

Tip of nose Chin 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.

Intrauterine Pressure Catheter

Requires ROM Pressure of

contractions measured 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

More accurate due to direct measurement of intrauterine pressure

Terminology for Describing Uterine Activity

Normal Hypotonus and Hypertonus Multiphasic – dysfunctional Tachysystole

Normal, Hypotonic & Hypertonic Contractions

Bell shaped

Uncoordinated contraction pattern

Weak contraction

Uterine Hypertonus

Hypertonus - insufficient relaxation between contractions. Uterus not soft between contractionsIf IUPC in place pressure between UC is 20-25 mmHg.

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

receptor sites

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

Tachysystole

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 periodor

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)

Category I(Reassuring FHR Tracing)

Continue to observe for approximately 30 minutes as long as FHR is reassuringConsider the following interventions:Maternal position changeIV Fluid hydrationIncreased frequency of observationDocument and report interventions

Did Uterine Tachysystole resolve?

YES NO

Continue increasing Pitocin as ordered

Decrease the Pitocin by ½. Continue to observe for an additional 30 minutes providing the FHR remains reassuring

If uterine Tachysystoledoes not resolve after 60

minutes, notify the provider

Category II / III(Indeterminate/Abnormal FHR Tracing)

Discontinue the Oxytocin administration Notify the provider and document report and interventions used to resolve the clinical situationInterventions:Maternal position changeIVF bolusOxygen at 10-12 LpmIncreased frequency of observationDocument and report interventions

Observe for 10-30 minutes, Pitocinmay be restarted at ½ the previous dose if FHR is reassuring and uterine activity is inadequateConsider IUPC placement

If uterine Tachysystole reoccurs, notify provider

YES NO