Labour Analgesia

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Labour Analgesia

• Human Reproduction and Sexuality Block
• Medical Students, Year 2
• Catherine Gallant MD FRCPC

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Introduction

• Objectives
• Understand what the pain of childbirth is
• Understand the pain pathways of labour
• Basic understanding of the options for labour
  analgesia
• Non-pharmacological/supportive
• Systemic analgesics
• Epidural analgesia
• Other regional analgesic techniques
• Basic understanding of the technique of epidural
  analgesia
• Anatomy of the lumbar spine and epidural space
• Categories of medications used in the epidural
  space
• Effects of epidural analgesia on the mother and
  fetus
• Complications of epidural analgesia

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Outline

• Pain of childbirth
• Effects on mother,fetus
• Pain management options
• Non-pharmacological
• Systemic analgesia
• Epidural analgesia
• Other regional techniques
• General anesthesia

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Pain of Childbirth

• Labour and delivery result in severe pain for
  most women !!!

• Causalgia (chronic)
• Digit amputation (acute)

• Severity varies greatly
• Severe to intolerable
• Nulliparous gt multiparous

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Pain of Childbirth
Chronic
Acute
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Pain of Childbirth
61
patients
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Pain of Childbirth
46
patients
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Pain of Childbirth

• Increased pain
• Occiput posterior
• h/o severe dysmenorrhea
• Young maternal age
• Increased maternal /or fetal weight

• Decreased pain
• Regular exercise
• Presence of supportive companion
• Realistic expectations

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Pain of Childbirth

• Three distinct kinds of pain
• Abdominal contraction pain
• Low back contraction pain
• Continuous low back pain
• Contraction pain worsens as labour progresses
• 1/3 experience continuous low back pain

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Pain of Childbirth

• Stimuli
• Pressure, distention, stretching, tearing
• Ischemia
• Organs
• Uterus
• Adnexa
• Cervix

• Pelvic floor
• Vagina
• Perineum

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Pain of Childbirth

• Visceral pain
• First stage
• T10 - L1
• Intrauterine pressure gt 25mmhg
• Somatic pain
• Second stage
• S2-S4

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Pain of Childbirth
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Effects

• Labour pain results in responses that can harm
  the mother fetus
• Effect of pain on physiology
• Respiratory
• Cardiovascular
• Humoral/Metabolic
• Uterine activity

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Pain Management Options

• Non-pharmacological
• Emotional Support
• Touch Massage
• Heat Cold
• Hydrotherapy
• Vertical Position

• Biofeedback
• TENS
• Acupuncture
• Hypnosis

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Pain Management Options

• Systemic Analgesia
• Opioids - meperidine, morphine, nalbuphine,
  fentanyl

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Systemic Opioids

• Indications for IV Opioid Analgesia
• No epidural
• Early labour
• Very late first stage
• Problems
• Maternal side effects
• Fetal side effects
• Neonatal side effects

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Systemic Opioids

• Intravenous Patient Controlled Analgesia (IV
  PCA)
• Benefits over intermittent injections
• Indications
• Alternative to epidural anesthesia
• Intrauterine fetal death
• Routine early labour use in selected cases
• N2O

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Pain Management Options Epidural variants

• Indications
• Contraindications
• Technique
• Preparation
• What goes in
• Maintenance
• CSE and PCEA
• The effects of epidural anesthesia
• Complications

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Epidural Analgesia

• Indications
• Pain !
• Obstetric
• Vaginal breech
• Vaginal twins
• Preeclampsia
• Medical Conditions
• Paraplegia
• Valvular heart disease

• Contraindications
• Consent
• Co-operation
• Active neurologic disorder
• Coagulopathy
• Hypotension
• Systemic / local infection

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Epidural Analgesia

• Technique
• Lumbar inter-spinous space, between L2 and L5
• Midline approach
• Patient sitting usually, well dorsiflexed to
  increase intra-laminar space

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Epidural Analgesia
Boundaries of the epidural space Bony and Tissue
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Epidural Analgesia

• Path of the epidural needle
• Skin, subcutaneous tissue
• Inter-spinous, supraspinous ligaments
• Ligamentum flavum

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Epidural Analgesia

• Bony margins that epidural needle must negotiate
  around

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Epidural Analgesia

• Drugs (what goes in)
• Local anesthetics
• Bupivacaine
• Ropivacaine
• Lidocaine
• Chloroprocaine

• Opioids
• Fentanyl
• Sufentanil
• Meperidine
• morphine

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Epidural Analgesia Effects

• Labour Progress
• First stage
• Second stage
• Mode of Delivery

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Epidural Complications

• Early
• IV toxicity
• LA toxicity
• Hypotension
• High block/total spinal
• Extensive motor block
• Fetal effects
• Urinary retention
• Labour progress
• Mode of delivery

• Late
• PDPH
• Neurological injury
• Epidural abscess
• Epidural hematoma
• Back pain

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Epidural Complications

• Local Anesthetic Toxicity
• Most to least toxic bupivacainegtropivacainegtlido
  cainegtchloroprocaine
• Usually secondary to accidental IV injection
• Accumulation may occur if long labour with
  multiple top-ups and/or progression to c-section

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Pain Management Options

• Alternative Regional Techniques
• First Stage
• Paracervical block

• Second stage
• Pudendal block
• Perineal infiltration

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Pain Management Options

• General anesthesia
• Rarely performed because of associated risks
• Some indications
• Stuck after-coming head
• Regional contraindicated
• Forceps
• Version

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Conclusion
There is no other circumstance where it is
considered acceptable for a person to experience
severe pain, amenable to safe intervention, while
under a physicians care.

American Society of Anesthesiologists
and American College of Obstetricians and
Gynecologists. Pain relief during labor. 1992.