Transcript Induction of Labour

Induction of Labour (IOL)
Maternal Newborn Orientation Learning Module
Reproductive Care Program of Nova Scotia, 2013
Reproductive Care Program of Nova Scotia, March 2012
http://rcp.nshealth.ca/publications/induction-labour-nova-scotia
Objectives
Review the following topics related to induction of
labour:
• Definition, indications, and implications for
women and the health care system
• Methods, with emphasis on prostaglandin and
oxytocin
• Practices to promote patient safety
Definitions
Induction is the ‘artificial initiation of labour
before its spontaneous onset’. (SOGC, 2001)
• Includes those methods applied to stimulate
contractions and progress in early labour.
Augmentation refers to the process of
stimulating contractions when progress in active
labour has slowed or stopped.
• Active labour has begun when contractions that are
frequent and/or regular have led to effacement and
dilatation of the cervix, at least 3-4 cm. (ALARM, 2012)
NS Induction of Labour 1990 to 2009
35
32.7
30
30
25
25
20
%
18.7
15
10
5
0
90-'94
95-'99
All deliveries
2000-'04
Women who labour
05-'09
What Has Contributed to the
Increased Rate of Induction?
• Changing
demographic
• Guidelines
interpretation
• Maternal choice
Benefits of Induction
Induction can enable vaginal birth when delivery is
indicated before the onset of spontaneous
labour.
Medical indications include postterm pregnancy*,
diabetes, HDP, PROM (without delay if GBS+), IUGR,
chorioamnionitis, suspected fetal compromise, hx of
precipitous birth…
*Postterm pregnancy is by definition > 42+0 weeks
gestation. Induction for postterm pregnancy should not
be initiated before 41+0 weeks.
Risks of Induction
• Inadvertent delivery before term
• Prolonged labour
• Cesarean Section
• Operative vaginal birth
• Postpartum hemorrhage
Implications for Women
Women told us during focus groups…..
• Induction allows control.
• Induced labour is more painful.
In 2005 to 2009, 38.3% of women who laboured
spontaneously received epidural analgesia; 67.6% of
women induced.
• Labour is less ‘natural’ during induction;
increases likelihood of more interventions.
If IOL is followed by C/S, contact with baby at and
following birth might be limited.
Implications for the Health Care
System
Method of delivery by type of
labour 2005 to 2009
90
80
70
60
50
40
30
20
10
0
Cesarean Section:
• 8.3% of women with
spontaneous labour
• 21.7% of women
induced
Oper. Vaginal Delivery:
Spont. Labour
C/S
SVD
IOL
Oper.VD
• 7.1% of women with
spontaneous labour
• 12.2% of women
induced
 Healthcare costs
Making the Decision to Induce
When the maternal/fetal benefits outweigh the risk
of induction (SOGC)…
• Many Labour and Birth Units maintain an ‘induction
list’ with inductions prioritized according to urgency of
need for delivery.
• Additional considerations include gestation or
cervical ‘readiness’ for labour.
Cervical Readiness for Labour
Bishop score:
 Points (0 to 3) are assigned for dilatation,
effacement, consistency and position of the cervix,
and fetal station.
 A score of ≤ 6 is unfavorable; if delivery is indicated,
cervical ripening is recommended as part of the
induction.
Cervical Ripening
Cervical ripening:
• Mechanical methods – Foley catheter, cervical
ripening balloon
• Only option for cervical ripening for a woman with a
previous cesarean section
• Allows simultaneous administration of oxytocin for
induction
Cervical Ripening
Prostaglandin E2 (PGE2)
• Prostin® (vaginal application) – initially 1 mg
followed by 2 mg in ≥6 hours, as necessary
• Cervidil® (controlled-release vaginal insert) –
10 mg; contraindicated if membranes ruptured
• Prepidil® (intracervical administration) – 0.5 mg
Risks of PGE2 are tachysystole or hypertonus with
or without abnormal FHR and rarely, uterine
rupture.
Recommendations for Care
Related to PGE2
• Following administration, a minimum of one to
two hours of electronic fetal monitoring is
suggested.
• Practices related to outpatient use of PGE2 vary
across Canada; in some facilities use of Cervidil®
requires hospital admission.
• Oxytocin can be initiated 30 to 60 minutes
following removal of Cervidil® and 6 or more
hours following administration of either Prostin®
or Prepidil®.
One Final Note about Cervical
Ripening…
• Misoprostol (PGE1) is used in the United States;
however, it is currently not recommended in
Canada except for ripening (and/or induction)
following IUFD.
Methods of Induction
• Amniotomy / ARM (artificial rupture of the
membranes)
• Results in increased levels of prostaglandin
• Risks include variable decelerations, infection and
prolapsed cord
• Oxytocin
Oxytocin
Oxytocin binds to receptor cells distributed
throughout the myometrium, stimulating
contractions.
Uterine response to oxytocin is widely variable.
Oxytocin is one of 12 ‘high-alert’ medications
identified by the Institute of Safe Medication
Practices (ISMP).
Safe Practices Related to Use of
Oxytocin
• Oxytocin is administered by IV infusion, ordered
and documented in mU/min.
• The dosage is carefully titrated according to a
clearly prescribed protocol, and maternal and/or
fetal response.
• A single protocol should be used consistently by
all members of the team.
10 units of oxytocin added to 1 litre of R/L or N/S:
1 mU/min = 6 ml/hour
Oxytocin Protocols
Low-dose protocol:
 initiate at 0.5 to 2 mU/min and increase by 1 to 2
mU/min q 30 to 60 minutes
High-dose protocol:
 initiate at 4 to 6 mU/min and increase by 4 to 6
mU/min q 15 to 30 minutes
*Always titrated according to maternal and/or
fetal response
Electronic Fetal Monitoring
The SOGC (2007) recommends:
During induction:
• Continuous monitoring while the rate of oxytocin
infusion is being titrated
• Interrupting continuous monitoring for periods of up
to 30 minutes (for ambulation, personal care and
hydrotherapy) once the infusion is stable and
provided the tracing is normal
During augmentation:
• Continuous monitoring
Recommendations from the RCP
QA Review re: Oxytocin
• There should be a single protocol for mixing and
administering oxytocin within each Labour and
Birth Unit.
• Oxytocin should be initiated at a low dose and
maintained at the lowest level possible to induce
contractions of normal frequency, strength and
duration.
• The infusion should be reduced or discontinued if
adverse effects occur.
• Care providers should be prepared to reduce the rate
as active labour is established.
Abnormal Uterine Response to
Oxytocin
Tachysystole – more than 5 contractions in
10 minutes, averaged over 30 minutes
Hypertonus – resting tone > 20 to
25 mmHg
Tachystole or Hypertonus:
Recommended Actions
• The oxytocin infusion should be quickly adjusted
downward until a normal contraction pattern
(q2-3 minutes with 30-60 seconds of relaxation
in between) is reestablished.
• The infusion should be discontinued if the
abnormal pattern persists for 10 minutes or
more, or if the FHR becomes atypical or
abnormal.
Restarting the Infusion
AWHONN suggests:
If discontinued for < 30 minutes, the oxytocin should
be restarted at ½ the rate at which the adverse
response occurred.
If discontinued for > 30 minutes, oxytocin should be
restarted at the initial dose.
True or False
1. Induction for postterm pregnancy should be
carried out between 40+0 and 41+0 weeks.
T
F
2. Induction of labour increases the likelihood of
having a cesarean section.
T
F
3. Prostin® is contraindicated if membranes have
ruptured.
T
F
4. Oxytocin infusion should be increased steadily
unless FHR decelerations occur.
T
F
True or False - Answers
1. Induction for postterm pregnancy should be
carried out between 40+0 and 41+0 weeks.
T
F
2. Induction of labour increases the likelihood of
having a cesarean section.
T
F
3. Prostin® is contraindicated if membranes have
ruptured.
T
F
4. Oxytocin infusion should be increased steadily
unless FHR decelerations occur.
T
F
Final Messages…
• Induction allows for labour and vaginal birth
when delivery is indicated prior to spontaneous
labour.
• Careful attention must be made to carrying out
induction safely, including administration of
induction medications and assessment of
maternal and fetal response.
• Accurate documentation and good communication
among team members are essential.
Thank you!
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moments to complete a short evaluation:
http://rcp.nshealth.ca/education/learning-modules/evaluation
If you have any questions, please contact the RCP
office at [email protected] or 902-470-6798