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Epidural Anesthesia

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Epidural Anesthesia, Combination Regional Anesthesia in Labor, Walking Epidural, Neuraxial Anesthesia in Labor

  • See Also
  1. Active Labor Anesthesia
  2. Latent Labor Anesthesia
  3. Non-Pharmacologic Pain Control in Labor
  4. Intrathecal Morphine
  5. Paracervical Block
  6. Pudendal Block
  • Indications
  1. Contractions regular and strong
  2. Fetal head engaged
  3. Adequate cervical dilatation
    1. Multiparous: Cervix dilated to 4-5 cm
    2. Nulliparous: Cervix dilated to 5-6 cm
  • Contraindications
  1. Coagulopathy
  2. Increased Intracranial Pressure
  3. Hypovolemia
  • Disadvantages
  1. Indwelling catheter limits mobility
  2. Larger volume of Anesthetic required to fill the epidural space
  3. Onset of pain relief delayed 15 minutes from catheter insertion (contrast with Intrathecal Morphine's instantaneous onset)
  • Technique
  1. Insert indwelling catheter into epidural space
    1. Gauge: 18-20
    2. Insertion Site: L3-4 interspace with Touhy Needle
    3. Elevate head of bed 20-30 degrees
  2. Early active phase
    1. Bupivacaine 0.25% 6-8 ml every 1 to 1.5 hours
    2. Spinal level: T10 to L1
  3. Later first stage to early second stage
    1. Bupivacaine 0.25% 8-12 ml every 1 to 2 hours
    2. Spinal level: T10 to S5
  1. Uses a combined injection of spinal (intrathecal) and Epidural Anesthesia
    1. Epidural needle enters epidural space
    2. Spinal needle is threaded through epidural needle and then punctures dura and enters subarachnoid space
      1. Spinal Anesthesia (intrathecal Analgesic or Anesthetic) is injected into subarachnoid space
    3. Spinal needle is withdrawn
    4. Epidural catheter is advanced within the epidural space
      1. Epidural catheter is left in place for further Epidural Anesthesia and its needle is withdrawn
  2. Lower dose Anesthetic (bupivicaine or ropivicaine) with or without Fentanyl (Duragesic)
    1. Anesthetic only (without Opioid) in subarachnoid space results in fewer side effects (see below)
    2. However, adding Opioid offers faster Analgesic onset and lower Anesthetic dosing
  3. Benefits
    1. Faster onset of pain relief with decreased rescue Anesthesia
    2. Fewer assisted vaginal deliveries
    3. Allows patients to remain ambulatory despite epidural
    4. Similar pain relief to standard epidural
    5. Shorter Second Stage of Labor
  4. Adverse Effects
    1. Increased maternal Pruritus and Nausea
    2. Nonreassuring Fetal Heart Tones
    3. Adverse effects are increased with Opioid and Anesthetic are used in contrast to Anesthetic alone
  5. Reference
    1. (2001) Lancet 358:19-23 [PubMed]
    2. Hattler (2016) Anesth Analg 123(4): 955-64 [PubMed]
    3. Grangier (2020) Int J Obstet Anesth 41:83-103 [PubMed]
    4. Simmons (2012) Cochrane Database Syst Rev (10): CD003401 [PubMed]
  • Adverse Effects
  • General
  1. Risks of maternal Hypotension (occurs in up to one third of patients)
    1. Preadministration of Normal Saline 500 to 1000 cc may prevent Hypotension in Epidural Anesthesia
  2. Systemic injection
    1. Stop if Dizziness or Tinnitus after test dose
  3. Fever
  4. Spinal Headache
  5. Nerve injury
  6. High Neuraxial Block (excessive analgesia) with cardiorespiratory compromise (1 in 4000)
  7. Respiratory arrest (1 in 10,000)
  8. Spinal catheter placement (1 in 15,000)
  • Adverse Effects
  • Labor progress and outcomes
  1. Higher risk of Labor Dystocia if Cervix <5 cm in early studies
    1. Early epidural: 21% Cesarean Section rate
    2. Late epidural: 11% Cesarean Section rate
    3. Lieberman (1995) Perinatal Confer, John's Hopkins
  2. More recent study shows no benefit to epidural delay
    1. Labor slowed only between 4-5 cm (not <4 cm)
    2. No increase in ceserean with early epidural
    3. Vahratian (2004) Am J Obstet Gynecol 191:259-65 [PubMed]
  3. Most recent data shows no increased rate of Assisted Delivery or cesarean delivery regardless of labor stage
    1. Anim-Somuah (2018) Cochrane Database Syst Rev (5): CD000331 [PubMed]
  4. Measures to reduce first-stage of labor time in Epidural Anesthesia
    1. Peanut ball with regular position changes reduces First Stage of Labor time by 87 minutes
    2. Delgado (2022) Obstet Gynaecol 42(5): 726-33 [PubMed]
  • References
  1. Schrock (2012) Am Fam Physician 85(5): 447-54 [PubMed]
  2. Smith (2021) Am Fam Physician 103(6): 355-64 [PubMed]