It initiates hyperventilation leading to maternal hypocarbia, respiratory alkalosis and subsequent compensatory metabolic acidosis. The oxygen dissociation curve is shifted to the left and thus reduces tissue oxygen transfer, which is already compromised by the increased oxygen consumption associated with labor
Electrodes are placed about 2cm over the T10-L1 dermatomes in 1st stage & S2-S4 in the 2nd stage
Central neuraxial blockade is the gold standard technique for labor analgesia that is currently available
Induction of labor& pain reief inlabor for undergraduate
Induction of LaborInduction of Labor
Dr Manal BeheryDr Manal Behery
Induction of labor is the artificial initiation ofInduction of labor is the artificial initiation of
labor prior to its spontaneous onsetlabor prior to its spontaneous onset
The artificial stimulation of labor thatThe artificial stimulation of labor that
has been started spontaneouslyhas been started spontaneously toto
increase the rate of progress of laborincrease the rate of progress of labor
TTime, place & preparationime, place & preparation
Time of inductionTime of induction:: Preferably early morningPreferably early morning
Place of inductionPlace of induction: where facility for: where facility for
intervention and fetal monitoring is availableintervention and fetal monitoring is available
Preparation of PatientPreparation of Patient :: Enema may be givenEnema may be given
to patients prior to inductionto patients prior to induction
Indication for InductionIndication for Induction
General conceptsGeneral concepts
Elective inductionElective induction
induction, in the absence of maternal or fetal indication,induction, in the absence of maternal or fetal indication,
should not be undertakenshould not be undertaken
-increase CS (especially, nulliparas)-increase CS (especially, nulliparas)
Emergent indicationEmergent indication
-ruptured membranes with chorioamnionitis-ruptured membranes with chorioamnionitis
severe preeclampsiasevere preeclampsia
Factors to assess prior to inductionFactors to assess prior to induction
--Contracted pelvisContracted pelvis
Pregnancy following classical C.sectionPregnancy following classical C.section
Pregnancy following repair of a vesico-vaginalPregnancy following repair of a vesico-vaginal
-Acute fetal distress-Acute fetal distress
-Abnormal presentation-Abnormal presentation
--Presence of active herpetic genital lesionsPresence of active herpetic genital lesions
Cervical RipeningCervical Ripening
promotion of cervical change bypromotion of cervical change by
pharmacological or other meanspharmacological or other means
not primarily intended to induce labor but tonot primarily intended to induce labor but to
increase the success of subsequent inductionincrease the success of subsequent induction
Modified Bishop’s ScoreModified Bishop’s Score
Favourable score->6 Best score->8
Stripping of membraneStripping of membrane
performed by inserting the index finger throughperformed by inserting the index finger through
the internal os as as far possible and rotatingthe internal os as as far possible and rotating
twice through 360 degrees to separate thetwice through 360 degrees to separate the
membranes from the lower segmentmembranes from the lower segment
Amniotomy (ARMAmniotomy (ARM((
WidelyWidely used methodologyused methodology
No anaesthesia or analgesiaNo anaesthesia or analgesia
Cord prolapseCord prolapse
Synthetic Oxytocin preparations, SyntocinonSynthetic Oxytocin preparations, Syntocinon
and Pitocin are commonly usedand Pitocin are commonly used
Syntocinon is avaiable in injectionsSyntocinon is avaiable in injections
Complications of SyntocinonComplications of Syntocinon
Incoordinate uterine action;Incoordinate uterine action;hyperstimulationhyperstimulation
Routes of administrationRoutes of administration
Vaginal-Gel orVaginal-Gel or
Local via catheterLocal via catheter
Mechanism of actionMechanism of action
Change the myometrial cellChange the myometrial cell
memb permeablity andmemb permeablity and
alteration in the membranealteration in the membrane
bound calciumbound calcium
sensitises the mometrium tosensitises the mometrium to
the oxytocinthe oxytocin
PGE2 has its collagenolyticPGE2 has its collagenolytic
activityactivityalter the groundalter the ground
substance of cervixsubstance of cervixcxcx
reasons for induction must be convincing and
risk and benefits must be discussed with patient
patient preference must be considered
ripen the cervix as much as possible
do not use oxytocin if cervix unfavourable
don't overestimate your ability to succeed
DOES LABOR PAIN NEEDDOES LABOR PAIN NEED
Potential effects of maternal hyperventilation and subsequentPotential effects of maternal hyperventilation and subsequent
hypocarbia on oxygen delivery to the fetushypocarbia on oxygen delivery to the fetus
Why is labour painfulWhy is labour painful??
Ischemia of uterine muscles.Ischemia of uterine muscles.
Dilatation and stretching of the cervix.Dilatation and stretching of the cervix.
Stretching of the perineum in the secondStretching of the perineum in the second
stage of labour.stage of labour.
Panadol + NSAIDPanadol + NSAID
Simple analgesia is usually ineffective in controllingSimple analgesia is usually ineffective in controlling
labour painlabour pain
The ideal analgesic in labourThe ideal analgesic in labour
Easy to administer.Easy to administer.
Safe to the mother and baby.Safe to the mother and baby.
Easily reversible if necessary.Easily reversible if necessary.
Does NOT interfere with uterine contractions.Does NOT interfere with uterine contractions.
Does NOT effect mobilityDoes NOT effect mobility..
Types of pain relief in labourTypes of pain relief in labour
Phar macologicalPhar macological
Essential in all cases.Essential in all cases.
Antenatal classes to educate the mothers onAntenatal classes to educate the mothers on
what to expect.what to expect.
Helps mothers to cope with pain andHelps mothers to cope with pain and
satisfaction with pain relief.satisfaction with pain relief.
Transcutaneous nerve stimulation(TENSTranscutaneous nerve stimulation(TENS((
Low grade electronic waves to nerves supplyingLow grade electronic waves to nerves supplying
the uterus via skin electrode.the uterus via skin electrode.
Provides good pain relief to 25% of patients.Provides good pain relief to 25% of patients.
Woman controls intensity and sensation patternsWoman controls intensity and sensation patterns
Drawback – interfers with FHRDrawback – interfers with FHR
Contraindication – cardiac pacemakersContraindication – cardiac pacemakers
Transcutaneous electrical nerve stimulation equipment
general Birthday Trust's latest survey, only about 5.5% of women use TENS
Intradermal Water InjectionIntradermal Water Injection
Hypnosis and acupunctureHypnosis and acupuncture
Reported to be successfulReported to be successful..
Needs special skill and preparationNeeds special skill and preparation..
Carries no risk to the mother or fetusCarries no risk to the mother or fetus..
??????Placebo effectPlacebo effect
Does this matterDoes this matter????????
Pethidine and diamorphine are thePethidine and diamorphine are the
commonly used drugs.commonly used drugs.
Given inter-muscular or intravenousGiven inter-muscular or intravenous
repeated when necessary.repeated when necessary.
Offers good pain relief for most patients.Offers good pain relief for most patients.
Short duration of action.Short duration of action.
Nausea and vomiting. (antiemetic(Nausea and vomiting. (antiemetic(
Can cross BPB respiratoryCan cross BPB respiratory
depression in the new born.depression in the new born.
Inhalational anesthesiaInhalational anesthesia
The commonest is nitrous oxide.The commonest is nitrous oxide.
Self administered to the patient via face mask.Self administered to the patient via face mask.
Given in a 50-50 mixture with oxygen (EntanoxGiven in a 50-50 mixture with oxygen (Entanox).).
Provides analgesia varying from good toProvides analgesia varying from good to
Under control of the patient.Under control of the patient.
Minimal adverse effects to mother andMinimal adverse effects to mother and
not adequate for second stage, instrumental delivery,not adequate for second stage, instrumental delivery,
suturing of perineum or manual removal of placenta.suturing of perineum or manual removal of placenta.
Light headedness and nausea.Light headedness and nausea.
Not suitable for prolonged useNot suitable for prolonged use..
Alternative Regional AnaestheticAlternative Regional Anaesthetic
Epidural blockEpidural block
Plastic catheter introduced into the epidural space.Plastic catheter introduced into the epidural space.
Catheter is left in and the analgesia is givenCatheter is left in and the analgesia is given
Bupivican andBupivican and FentanylFentanyl
The most effective pain relief.The most effective pain relief.
The absence of pain allows enjoyment andThe absence of pain allows enjoyment and
control of labour.control of labour.
Reduces maternal fatigue and anxiety.Reduces maternal fatigue and anxiety.
Ideal in high risk pregnancies e.g. breech, MP,Ideal in high risk pregnancies e.g. breech, MP,
and PET.and PET.
Restriction of movement during labour.Restriction of movement during labour.
Requires CTG.Requires CTG.
Requires resident anesthesia, cardio-Requires resident anesthesia, cardio-
respiratory facilities and one to one care.respiratory facilities and one to one care.
?increase rate of instrumental delivery.?increase rate of instrumental delivery.
Failure 3%.Failure 3%.
Epidural tap (headache)Epidural tap (headache)
? Back pain.? Back pain.
Paralysis !!!!!!!!!.Paralysis !!!!!!!!!.
Analgesia used in second stage andAnalgesia used in second stage and
third stagethird stage..
Nerve blocks.Nerve blocks.
Spinal anesthesia.Spinal anesthesia.
General anesthesia.General anesthesia.
Pudendal blockPudendal block
Performed by the obstetricianPerformed by the obstetrician..
Used for outlet forceps and vacuumUsed for outlet forceps and vacuum
Spinal anesthesiaSpinal anesthesia
Can be used for …Can be used for …
Instrumental delivery.Instrumental delivery.
Manual removal of placenta.Manual removal of placenta.
Repair of third degree tear.Repair of third degree tear.
Contraindications to spinal or epiduralContraindications to spinal or epidural
Maternal refusal.Maternal refusal.
Sever back deformities,Sever back deformities,
Local infection.Local infection.
Coagulation disorders.Coagulation disorders.