Transcript Cervical Ripening: Induction/Augmentation of Labor

Cervical Ripening and
Induction/Augmentation of Labor
Daren Sachet, RNC/MPA
Objectives
List the indications and
contraindications for cervical ripening
and induction of labor.
Discuss the different methods used
for cervical ripening, labor induction
and augmentation.
Discuss the nurses role in the safe
administration of cervical ripening and
induction agents.
Definitions
What is cervical ripening?
Preparation of an unfavorable cervix for
labor induction
What is induction?
Stimulation of uterine contractions
before the spontaneous onset of labor
What is augmentation?
Correcting ineffective uterine
contractions or hypocontractility
Incidence in the United States
National Center for Health Statistics (NCHS) year 2000
data
 Induction of labor- 19.9%
 labor augmentation-17.9%
National Center for Health Statistics (NCHS) year 2009
data
 Induction of labor - 22.5%
 Labor augmentation - 19.9%
Since 1989, this represents a 137% increase in
induction and a 75% increase in augmentation
rates.
NCHS, 2009
Risk-Benefit
Risk of Cesarean Birth for Nulliparous
Women:
17.2% spontaneous labor
30.4% induced labor
77.7% increase for induction
Reisner et al., 2009
Use of pharmacologic agents
increases risk for tachysystole,
indeterminate or abnormal FHR
patterns and failure to progress
Cascade of Interventions
Related to Induction of Labor
Economic Costs
Spontaneous Labor/vaginal birth
$4000
Induction of labor/vaginal birth
$5000
Cesarean Birth/scheduled
$7000
Cesarean Birth/failed induction
$7500
Simpson, KR., 2009
Indeterminate/Abnormal FHR
(Category II and Category III FHR)
Nearly twice the risk, possibly related to:
Tachysystole
Early Amniotomy
Labor Dystocia
Longer Labor
Less Fetal Tolerance
Glantz, 2005, Simpson, KR., 2009
Risks to the Infant
Indications for Cervical Ripening
and Induction of Labor
Decrease the rate in patients with elective delivery at 37 to 39 weeks
gestation.
Joint Commission National Quality Core Measure PC-01
Contraindications-Induction of
Labor
Generally, the contraindications for labor
induction are the same as those for
spontaneous labor and vaginal birth
Vasa previa or complete placenta previa
Transverse fetal lie
Umbilical cord prolapse
Previous transfundal uterine incision
Active genital herpes infection
Pelvic structural deformities
Invasive cervical cancer
Situations Requiring Special
Attention
 One or more previous low-transverse cesarean births
 Breech presentation
 Maternal heart disease
 Multifetal pregnancy
 Polyhydramnios
 Presenting part above the pelvic inlet
 Severe hypertension
 Abnormal FHR patterns requiring emergent birth
 A trial of labor after a previous cesarean birth or history
of prior uterine scar
ACOG 2009, 2002
Indications for Augmentation of
Labor
Dystocia
Uterine Hypocontractility
Uterine hypocontractility should be
augmented only after both the maternal
pelvis and fetal presentation have been
assessed.
ACOG 2009
Pre-induction/Ripening Criteria
Availability of trained nursing and provider staff
Cervical ripening agents should be administered
at or near the labor and birth suite where uterine
activity and FHR can be monitored continually
Assessment of gestational age, cervical status,
pelvic adequacy, fetal size and presentation
A physician capable of performing a cesarean
birth should be readily available.
ACOG 2009
Criteria continued
Considerations to any risks to mother or fetus
Patient counseling regarding indications,
agents/methods, and possibility of repeat
induction or cesarean birth
The medical record should document that a
discussion was held between the pregnant
woman and her health care provider
ACOG 2009
Bishop Score
Has been shown to be an important determinant of
the success or failure of induction
Score
Dilate
cm
Efface%
Station
Consistency
Pos Cx
0
Closed
0-30
-3
Firm
Post
1
1-2
40-50
-2
Med
mid
2
3-4
60-70
-1/0
Soft
Ant
3
5-6
80
+1/+2
___
___
Cervical Status
Includes documentation of the Bishop
score and the presence or absence of
uterine activity
For women at term, a Bishop score of 6 or
more may be useful in predicting onset of
spontaneous labor within 7 days
Rozenberg, Goffinet & Hessabi, 2000
Cervical Ripening Agents
These agents may soften the cervix, change the
Bishop score
Mechanical/Non pharmacologic Methods
Laminaria tents
Synthetic hygroscopic dilators (Lamicel and
Dilapan)
Balloon catheters
Pharmacologic Methods
 Prostaglandins (E1 & E2)
Oxytocin
Mechanical Dilators
Laminaria Tents
Synthetic Osmotic Dilators
Cervical Ripening Balloons
Laminaria Tents
Synthetic Osmotic Dilators
• Lamicel
• Dilapan
Balloon Catheters and
Extraamniotic Saline Infusion
Foley Catheter
Extraamniotic saline infusion- balloon
catheter
Double Balloon Cervical Ripening Catheter
Results seen within 8-12 hours after insertion
Mechanical Ripening Devices
• Double balloon
device
• Foley catheter
Pharmacologic Methods
Not recommended for use in women with
history prior c-birth or uterine scar
Prostaglandin E1: Misoprostol (Cytotec)
Oral, sublingual or vaginal use
Wide variations exist in time of onset of
uterine contractions
Peak action is approximately 1-2 hours but
can be up to 4-6 hours
Re-dosing Parameters
Re-dosing is permissible if:
 Still unripe cervix?
Happy baby?
Redosing is withheld if:
Complications with Misoprostol
(Cytotech)
Tachysystole
Indeterminate/Abnormal FHR pattern
Precipitous Labors
Uterine Rupture
Need careful maternal/fetal assessments
Need consent/protocols
ACOG, 2009
Prostaglandin E2-Dinoprostone
Prepidil
Perform speculum exam, introduce gel just below
cervical os
Patient should remain recumbent for at least 30
minutes
Uterine contractions usually occur within one hour of
administration- peak activity within 4 h
Prostaglandin E2-Dinoprostone
Cervidil
Cervical Ripening Agents
Minimum safe interval from prostaglandin
to oxytocin administration not established
Manufacturers guidelines recommend
Misoprostol- at least 4 hours after last dose
Prepidil- 6-12 hours after last dose
Cervidil-30-60 minutes after removal of
vaginal insert
Not contraindicated with PROM
Induction and Augmentation of
Labor
Mechanical methods of Induction of
Labor
Stripping the Membranes
Amniotomy
Artificial rupture of membranes
• NURSES DO NOT PERFORM AMNIOTOMY
Oxytocin
Most commonly used induction agent in the
United States and worldwide
Kelly & Tan, 2001
Synthetic oxytocin is chemically and
physiologically identical to endogenous
oxytocin
Half life between 10-12 minutes
Dawood, 1995a; Arias, 2000
3 – 4 half-lives to reach steady state
Full effects of oxytocin cannot be
determined until steady-state concentration
has been achieved.
Physiologic steady state 40 min, basis for
dosing interval.
Endogenous Oxytocin
First Stage Labor
Maternal circulating concentration 2-4
mU/min
Fetal Contribution
3 mU/min
Combined effects = 5-7 mU/min
Second Stage Labor
Surge of oxytocin at Ferguson’s reflex
Simpson, KR, 2009
Response to Oxytocin
Oxytocin Dosing
Considerable controversy exists about dosage
and rate increase intervals-there is no consensus
in the literature
Oxytocin Dosing
Only increase oxytocin rate if:
FHR is normal
Labor has not progressed 0.5 -1 cm/hr
Contractions are no closer than every 2-3
minutes
Excessive uterine activity over the course
of 1 hour in first stage of labor is
associated with an umbilical artery pH ≤
7.11 at birth
Decrease or discontinue oxytocin in active
labor
Simpson, KR, 2009
Physiologic Dosage
Start with doses of 0.5-1 mU/min
Increase in 1-2 mU/min increments every 3040minutes until contractions are every 2-3
minutes apart and labor is progressing ACOG, 1999a,
SOGC, 2001
Current literature suggests that 90% of pregnant
women at term will have labor successfully
induced with 6mU/min or less of oxytocin
Dawood, 1995a, 1995b; Seitchik, Amico et al., 1984
Oxytocin Administration
No maximal dose of oxytocin has been
firmly established
Doses above 40mU/min are rarely used,
except in cases of intrauterine fetal demise
(IUFD).
Infusion rates >=20mU/min can decrease
free water clearance by the kidney
resulting in water intoxication.
Smith and Merrill, 2006
High Dose Oxytocin
According to ACOG (2009), protocols that
involve “high-dose” oxytocin are acceptable;
however, high-dose oxytocin is associated with
more uterine tachysystole
SOGC recommends using the minimum dose to
achieve active labor, increasing the dosage no
more frequently than every 30 minutes and
reevaluating the clinical situation if the oxytocin
dosage rate reaches 20 mU/min
Oxytocin and Medication Safety
Nursing responsibilities
Titrate oxytocin infusion drip to achieve
three contractions in 10 minutes with a
duration of 60-90 seconds
Closely monitor fetal response, uterine
activity and resting tone
Monitor maternal vital signs and fluid
balance
Potential Complications-Oxytocin
Tachysystole
Abruptio placentae
Uterine rupture
Hyponatremia (water intoxicaiton)
Nursing Interventions for
Tachysystole with Normal FHR
pattern
Lateral positioning of mother
Increase IV fluid (LR)
If uterine activity not returned to normal
after 10 minutes,  oxytocin by half
If tachysystole persists, D/C oxytocin until
tachysystole resolves
Consider terbutaline 0.25 mg SQ, with
order
ACOG, 2010, AWHONN, 2008
Nursing Interventions for
Tachysystole with Indeterminate
or Abnormal FHR pattern
Discontinue or reduce oxytocin
Lateral positioning of Mother
IV fluid bolus (LR)
If hypotensive, (as with epidural) contact
anesthesia provider, prepare to administer
epinephrine, with order
Oxygen, 10 LPM, non-rebreather mask
Consider terbutaline 0.25 SQ, with order
If unresolved, inform provider immediately,
possibly prepare for C/S.
(ACOG 2010)
Resuming Oxytocin
Women attempting VBAC
Should women with a previous cesarean birth
undergo induction or augmentation of labor?
Spontaneous labor more likely to result in successful
VBAC
Some studies show women with oxytocin
administration undergoing TOLAC may be at
increased risk of uterine rupture than spontaneous
labor. Other studies have not.
Use of prostaglandins are associated with a higher
rate of uterine rupture and are NOT
RECOMMENDED
ACOG, 2010
VBAC Success Rates
VBAC Induction
Physician and surgical team must be
immediately available throughout active
labor
Recommend 1:1 nursing care with an
experienced RN
Continuous EFM
Must have ability to perform emergency
C/birth
Nursing Implications with VBAC
Induction/Augmentation
Access to operating room readily available
Monitor as for high risk
Signs and symptoms of uterine
rupture/dehiscence of prior scar
Patient c/o increasing pain and tenderness even with
epidural
Presentation may take place over period of time or
suddenly like “something has given away”
Vomiting, syncope, vaginal bleeding,
tachycardia, fetal bradycardia or absent fetal
heart rate
Management
Maternal stabilization and immediate
cesarean birth
Key to diagnosis is suspicion of uterine
rupture
Simpson, K.R & Creehan, P., 2001
Conflict? No way!
Summary
Evidence suggests that cervical ripening can
increase the chances of successful induction
Misoprostol (cytotec) is becoming more widely
used for cervical ripening and labor induction
No elective inductions before 39 completed weeks
of gestation
Protocols should be based on ACOG/AHWONN
standards and guidelines
Multiple factors contribute to the steady increase in
the rate of induction in the United States
Consider implementation of an Induction of Labor
Patient Safety Bundle.
References
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
American Academy of Pediatrics & American College of Obstetricians and Gynecologists.
(2007). Guidelines for Perinatal Care (6th Ed.). Elk Grove, IL, Washington DC: Authors.
National Center for Health Statistics (NCHS) year 2000 - 2009 data
American College of Obstetricians and Gynecologists. (August, 2009). Induction of Labor,
Practice Bulletin, Clinical Management Guidelines for Obstetrician-Gynecologists, Number107.
Washington DC: Author.
American College of Obstetricians and Gynecologists. (November, 2010). Management of
Intrapartum Fetal Heart Rate Tracings, Number116. Washington DC: Author.
American College of Obstetricians and Gynecologists. (August 2010).Vaginal Birth After
Previous Cesarean Delivery, Practice Bulletin, Clinical Management Guidelines for ObstetricianGynecologists, Number115, Washington DC: Author.
Association of Women’s Health Obstetric and Neonatal Nurses. (2010). Guidelines for
Professional Registered Nurse Staffing for Perinatal Units, Washington DC: Authors
Glantz, J (April 2005). Elective Induction vs. spontaneous labor Associations and Outcomes. Ele
Med. 50(4):235-240.
International Classification of Diseases, Code ICD-9-CM Description Shortened Description Table
Number 11.07: Conditions Possibly Justifying Elective Delivery Prior to 39 Weeks Gestation
(Ver. 2011A)
Joint Commission. (2010). Specifications Manual for Joint Commission Quality Core Measures
http://jointcommission.org/releases/TJC2010A/MIF0166.html
Phaneuf S., et al, Loss of myometrial oxytocin receptors during oxytocin-induced and oxytocinaugmented labour. Journal of Reproduction & Fertility 2000;120(1):91-97.
Simpson, K.R., (2008). Cervical Ripening and Induction and Augmentation of Labor. 3rd edition.
Association of Women’s Health, Obstetric and Neonatal Nurses. Washington DC.
Tita, A.,et al. (2009). Timing of elective preterm and neonatal outcomes. (Electronic Version).
NEJM. 360:2, 111-120