induction and augmentation of labour

INDUCTION AND AUGMENTION OF

LABOUR

PRESENTED BY:HEMLATAM.Sc.Nursing 2nd YearM.M.CON

CASE SCENARIO

Mrs. X was referred from community with a POG of 40 weeks + 4 days not in labour . All her scans, blood tests had been in normal limits. She had no problem during her pregnancy and had no previous medical or surgical problems.

INTRODUCTION Initiation of uterine contraction (after

the period of viability) for the purpose of Vaginal Delivery.

DEFINITIONS Induction Of Labour

(IOL)

Artificial initiation of labour mechanism prior to its spontaneous onset after 28 wks of gestation i.e. after period of viability but before spontaneous onset of labour with aim of vaginal delivery.

DEFINITIONS

AUGMENTATION OF LABOUR-

The artificial stimulation of labor that has been started spontaneously to increase the rate of progress of labor

Q. What is the difference between augmentation and induction of labour INDUCTION OF

LABOUR

Initiation of labour mechanism prior to its spontaneous onset

AUGMENTATION OF LABOUR

Increase the rate of progress of labor

PURPOSES OF IOL

Risk of continuation of pregnancy either to the mother or fetus is more.

PRELIMINARIES-

Gestational age Pulmonary maturity of

the fetus

INDICATION FOR IOL

CONTRAINDICATION OF IOL

Contracted pelvis and CPD Malpresentation (breech , transverse or

oblique lie) Previous classical ceasearean section or

hysterectomy Uteroplacental factors: unexplained

vaginal bleeding , vasa praevia, placenta

praevia

High risk pregnancy with fetal compromise Active genital herpes infection Heart disease Pelvic tumour Elderly primigravida with obstetric or

medical complications Umbilical cord prolapsed Cervical carcinoma.

CONTRAINDICATION OF IOL

PARAMETERS TO ASSESS PRIOR TO IOL

MATERNAL To confirm the indication for IOL Exclude the contraindication of IOL Assess Bishop score (>6,

favourable) Perform clinical pelvimetry to

assess pelvic adequacy Adequate counselling about the

risks, benefits and alternatives of IOL with the women and the family members

PARAMETERS TO ASSESS PRIOR TO IOL

FETALTo ensure fetal gestational

age To estimate fetal weight

(clinical and USG )Ensure fetal lung maturation

statusEnsure fetal presentation

and lie Confirm fetal well- being

FACTORS FOR SUCCESSFUL IOL

Period of gestation- term or post term

Pre- induction score- Bishop score >6 is favorable .

Cervical ripening - favourable in parous women and in case with PROM

FACTORS FOR SUCCESSFUL IOL

Sensitivity to uterus- positive oxytocin sensitivity test is favourable to IOL.

Presence of fibro-nectin in vaginal swab (> 50ng/ml) - favorable for successful IOL

Case profile - a low bishop score < 5 is unripe and unfavourable cervix.

CERVICAL RIPENING

CERVICAL RIPENING

Series of complex biochemical changes in the cervix which is mediated by the hormones.

There is alteration of both cervical collagen and ground substances .

Ultimately the cervix become soft and pliable.

MODIFIED BISHOP SCORE

Proposed by Bishop in 1964 (3) and is the most widely used score.

It was originally proposed to determine the suitability of a patient for IOL in patients who were parous, at term , had an uncomplicated pregnancy and the fetus was in cephalic presentation.

MODIFIED BISHOP SCOREFavourable score->6 Best score-8

MODIFIED BISHOP SCORE

Burnett later on modified the original Bishop’s score giving a maximum score of 2 to each of Bishop's five categories, giving a total maximum score of 10.

He considered effacement in terms of length and not percentage and considered previous term birth and cephalic presentation to be pre-requisites for induction.

TIME, PLACE & PREPARATION Time of induction: Preferably early morning

Place of induction: where facility for intervention and fetal monitoring is available

Preparation of Patient : Enema may be given to patients prior to induction

•Time of induction: Preferably early morning•Place of induction: where facility for intervention and fetal monitoring is available•Preparation of Patient : Enema may be given to patients prior to induction

•Time of induction: Preferably early morning•Place of induction: where facility for intervention and fetal monitoring is available•Preparation of Patient : Enema may be given to patients prior to induction

METHODS OF INDUCTION

OF LABOUR

MECHANICAL MEDIC

AL SURGIC

AL COMBINED

MECHANICAL

Nipple Stimulation Sweeping membranes Extra Amniotic insertion

catheter/balloon

Extra Amniotic insertion catheter/balloon

MEDICAL METHOD OF IOL

Oxytocin Prostaglandins (PGs) Progesterone receptor antagonist Relaxin


OXYTOCINNeurohormone originating hypothalmus and secreated by the posterior lobe (pituitary gland)Uterine activity (CONTRACTION)

Produce cervical dilation and effect delivery (WHEN RIPEN)


OXYTOCINDOSE- 0.5 -2.5 mu/minInitiated at the dosage of 1 mu/min , with with increases of 1 or 2 mU/minute every 20–30 minutes until a maximum administration rate of 16–32 mU/minute is reached or adequate uterine activity is present


Prostaglandins (PGE1,PGE2):

It act locally on the contiguous cells and both causes the myometrial contraction .

Intracervical application of dinoprostone ( PGE2-0.5mg) gel is the gold standard for cervical ripening


Prostaglandins (PGE1,PGE2): It may be repeated after 6

hours for 3 – 4 doses if required.

The women should be in bed 30 min following application and is monitored for uterine activity and fetal heart rate .

Misoprostol PGE1

ROUTE- Transvaginally or orally

DOSE- 25µg vaginally every 4 hours is found either superior or similarily effective to that of PGE2

for cervical ripening and labour induction. Maximun dose is 6-8

Misoprostol PGE1

CONTRAINDICATED-previous LSCS.

SIDEEFFECT - Uterine hyperstimulation , meconium stained liquor and fetal heart irregularities

MIFEPRISTONE It blocks both progesterone and

glucocorticoid receptor . RU 486

200mg vaginally daily for 2 days has been found to ripen the cervix and to induce labour.

Onapristone is a more selective progesterone receptor antagonist.

RELAXIN

Polypeptide hormone ( similar to insulin, produced by the ovaries, decidua, and chorion)

Because it affects connective tissue remodeling, it has been

studied as a cervical ripening agent.

RELAXIN

Several clinical trials using purified porcine relaxin, administered either vaginally or intracervically, demonstrated its effectiveness in cervical ripening.

Recently, however, studies employing vaginal recombinant human relaxin (1–4 mg) have shown no significant benefit as a pre-induction cervical ripening agent

SURGICAL METHOD OF IOL ARTIFICIAL RUPTURE OF MEMBRANE

ARM (Artificial Rupture of Membarne)

INDICATION :

Abruption placentaChronic hydroaminosSevere pre-

eclampsia /eclampsiaTo place scalp

electrode for electronic fetal monitoring.

CONTRAINDICATIONS:

IUFD

Maternal AIDS

Genital active Herpes Infection

PROCEDURE

Preliminaries : empty the bladder . the procedure can be done in labour room or in OT if the risk of cord prolapsed is high

Actual steps 1. Position the patient in lithotomy position2. Full surgical asepsis to be maintained 3. Two fingers are introduced into the

vagina smeared with antiseptic ointment4. The index finger is passed through the

cervical canal beyond the internal os

PROCEDURE

5. The membranes are swept free from the lower segment as far as reached by the fingers

6. With one or two fingers still in the cervical canal with the palmer surface upwards , a long kocher’s forceps with the blades closed or an amnion hook is introduced along the palmer aspect of the fingers up to the membranes

7. The blades are opened to seize the membranes and are torn by twisting movemements

8. Amnihook is used to scratch over the membranes . This is followed by visible escape of amniotic fluid .

ARM (Artificial Rupture of Membrane)

SEPARATION OF THE MEMBRANE (LIBERATION

OF PROSTAGLANDINS

STRETCHING OF THE CERVIX

REDUCTION OF AMNIOTIC FLUID VOLUME

TIMING

AMNI HOOK

RESEARCH EVIDENCE

HAZARDS OF ARM

COMBINED METHODS

SCHEME OF INDUCTION PROTOCOL

SUMMARY

ANY QUESTIONS

RESEARCH ABSTRACT

TITLE: Misoprostol versus Foley catheter insertion for induction of labor in pregnancies affected by fetal growth restriction.

AUTHOR:Chavakula PR, Jeyaseelan, et al

OBJECTIVE: To compare 25μg of vaginal misoprostol with a Foley catheter for induction of labor (IOL) for fetal growth restriction.

RESEARCH ABSTRACT METHODS: A randomized controlled trial was

conducted in a tertiary center in South India. Women with fetal growth restriction (n=100) were randomized to be induced with three doses of vaginal misoprostol (25μg) every 6hours or with an intracervical Foley catheter, inserted 12hours before rupture of membranes, and oxytocin if needed. The primary outcome was uterine tachysystole with fetal cardiotocography abnormalities. Secondary outcomes pertained to effectiveness, complications, and patient satisfaction.

RESEARCH ABSTRACT RESULTS: One woman in the misoprostol group and none in

the Foley catheter group had uterine tachysystole. The duration of labor from IOL to delivery was similar in both groups (P=0.416). More women in the misoprostol group had a vaginal delivery within 12hours (26.1% versus 5.6%; P=0.005). Women induced with misoprostol were less likely to deliver by lower-segment cesarean delivery (15.2% versus 29.6%; P=0.168) and to require oxytocin augmentation (60.9% versus 85.2%; P=0.007). Complications were few in both group.

CONCLUSION: Few women had uterine tachysystole with cardiotocography abnormalities. Vaginal misoprostol at 25μg was more effective than a Foley catheter for IOL in fetal growth restriction

CONCLUSION

Labor induction appears to be a safe alternative to spontaneous labor. Regardless of the method employed. The goal of labor induction must always be to ensure the best possible outcome for mother and newborn.

induction and augmentation of labour

Health & Medicine