Transcript Obstetric analgesia and anesthesia

Obstetric analgesia
and anesthesia
Dr Hiba Ahmed Suhail
M.B. Ch. B./F.I.B.O.G.
College of medicine
University of Mosul
The major objectives of obstetric analgesia
and anesthesia include:
1- Pain control during labour and delivery that
is safe for mother and fetus
2- Anesthetic management during cesarean
delivery that does not harm the mother or
the neonate.
3- Assisting the obstetrician with blood
pressure and heart rate of complicated
pregnancy and with the management of
comorbidities during labour.
Labor pain in the first stage
Uterine contractions leading to : myometrial
ischemia. The pain felt through hypogastric
plexuses , pre aortic plexuses to spinal cord
through (T10-L1).
Cervical dilatation and stretching Sensation
pass through nerve entering to sacral root.
At this stage this pain is visceral pain, diffuse,
poorly localized , in lower abdomen radiated
to the back.
Labor pain in the second stage
Uterine contractions
Pressure on the pelvic floor structures .
Stretching of the perineum
The last two felt through pudendal nerve
(S2, 3, 4) .
This pain is somatic pain so its well localized.
Pain control
Analgesia
 non pharmacological
 pharmacological
• parenteral
• inhalational
Anesthesia
 General anesthesia
 Regional anesthesia
• spinal
• epidural
 Regional block
• Pudendal
• Para cervical
Analgesia:
Analgesia refer to pain relief not involve the removal of
complete sensation it is include:
1-non pharmacological
Effective in relieving mild pain
 Massage.
 Homeopathy.
 Acupuncture.
 Hypnosis.
 Emotional support.
 Transcutaneous electrical nerve stimulation TENS
work by block pain fibres in posterior ganglia of the
spinal cord by stimulating small afferent fibres the
( gate theory ) it does not reduce pain score.
2- Pharmacological analgesia
Ideal analgesia should be:Easily administered.
Rapid onset of action.
Provide good analgesia.
No or low side effect on both mother and
fetus.
No effect on the process of labour ( not
affect uterine contraction or pelvic floor
tone)
 Parenteral ( Opiates)
Fentanyl
More potent synthetic analgesia .
Easily administered ( parenteral ).
Rapid onset.
Short duration of action
Cross placenta and cause neonatal complications.
Side effect GIT ( nausea , vomiting , delay gastric
emptying and constipation ),CNS ( confusion ) and
respiratory depression.
Inhalational analgesia Nitrous oxide NO
mixed with oxygen Entonox has:
Quick onset.
Short duration of effect.
More effective than pethidine.
It used for short duration latter on in labour or
while awaiting for epidural analgesia.
Side effect include nausea light headache and
not suitable for prolonged use.
Excreted through the lung.
Epidural (extradural) analgesia and anesthesia
Play important role in obstetrics.
The decision to have it should be combined between
woman obstetric team and anesthetist.
Is injected into the epidural space between L2 - L3
or L3-L4.
It necessitates a block from the T10 to the S5
dermatomes
A test dose is given to confirm the catheter position,
if no unwanted signs is observed after 5 min of
injection, a loading dose can be administered.
The main indications
1)
2)
3)
4)
5)
6)
Effective pain relief.
Prolonged labour.
Hypertension.
Multiple pregnancy.
Certain medical disease (cardiac disease).
High risk of operative delivery
The main contraindication:
1)
2)
3)
4)
5)
Coagulation disorder.
Local or systemic sepsis.
Hypovolaemia.
Insufficient numbers of trained staff.
Patient refusal.
Complications:
Maternal Complications:
1) Accidental dural puncture causing post dural
headache due to leakage of CSF mainly in the top
of the head and relieved by lying flat treated by
injection of autologous blood patch in the epidural
space.
2) Accidental total spinal anesthesia injection of local
anesthetic drug in subarachnoid space.
3) Hypotension treated by IV bolus isotonic solution
vasopressor phenylephrine.
4) Respiratory failure.
5) Loss of consciousness.
6) Death intubation ventilation circulatory support
delivery.
7) Spinal haematoma.
8) Drug toxicity (injection in to blood vessels).
9) Bladder dysfunction over distension catheterization.
10) Hypotension un common here but more in spinal
anesthesia .
11) Cardiac arrest.
Fetal complications
1) Fetal compromised if maternal hypotension
developed.
2) Short term respiratory depression of the
baby because of using opiates in epidural
solution which is a mixture of low dose
local anesthesia bupivacaine and opiates
fentanyl.
Anesthesia
Anesthesia refer to rendering the patient
completely insensate to pain it is either general or
local Combined spinal epidural analgesia has the
advantage of producing rapid onset and provision
of prolonged analgesia.
1) Regional anesthesia involve administration
of local anesthetic to render specific part of
body insensate In obstetrics it consist of
spinal and epidural.
Spinal anesthesia:
1.
2.
3.
4.
5.
Drug here small volume of local anesthesia
inject into subarachnoid space.
It considered more effective.
Faster onset.
Indications anesthesia for :
Caesarean section.
Trial of instrumental delivery in theatre.
Manual removal of placenta.
Repair of difficult vaginal or perineal tear.
Used when GA are contraindicated
It is not used for analgesia in labour.
Complication for spinal anesthesia:
1- Headache.
2- Convulsion (rare).
3- Blindness (rare).
4- Hypotension.
5- Bradycardia.
6- Injury to spinal cord.
7- Hematoma.
8- Infection.
9- Retention of urine
10- Fair of technique.
Contraindication :
1) Hypovolemia.
2) Clotting disorders.
3) Septicemia.
4) Aanatomical deformities.
5) Neurological disease.
6) Patient refusal.
Epidural Anesthesia
In cesarian delivery, a block extending
from the T4 to the S1.
2) General anesthesia given IV or inhalation to
render patient unconscious and all body
insensate.
Indications of GA.
1. Emergency CS
2. When regional anesthesia is contraindicated.
3. Mother prefers.
4. A prolonged surgery.
5. No available staff for regional anesthesia.
Risks of GA.
1. Aspiration of gastric content.
2. Neonatal depression.
Regional blocks:
Para cervical block the innervation of the uterus
and cervix injection of LA submucosally in to
the fornix of vagina laterally to cervix It effect
only first stage of labour D and C analgesia It
can cause fetal bradycardia.
2) Pudendal block Somatic pain of second stage
of labour transmitted via pudendal n., it involve
injection of local anesthetic below the ischial
spines ( the approximate location of the
pudendal nerve ). This block is administered in:
Second stage of labor.
Operative delivery.
Suturing of perineum following delivery.
1)