II. Indications
- Contractions regular and strong
- Fetal head engaged
- Adequate cervical dilatation
- Multiparous: Cervix dilated to 4-5 cm
- Nulliparous: Cervix dilated to 5-6 cm
III. Contraindications
IV. Disadvantages
- Indwelling catheter limits mobility
- Larger volume of Anesthetic required to fill the epidural space
- Onset of pain relief delayed 15 minutes from catheter insertion (contrast with Intrathecal Morphine's instantaneous onset)
V. Technique
- Insert indwelling catheter into epidural space
- Gauge: 18-20
- Insertion Site: L3-4 interspace with Touhy Needle
- Elevate head of bed 20-30 degrees
- Early active phase
- Bupivacaine 0.25% 6-8 ml every 1 to 1.5 hours
- Spinal level: T10 to L1
- Later first stage to early second stage
- Bupivacaine 0.25% 8-12 ml every 1 to 2 hours
- Spinal level: T10 to S5
VI. Technique: Combination Regional Anesthesia (Walking Epidural, low-dose epidural protocol)
- Uses a combined injection of spinal (intrathecal) and Epidural Anesthesia
- Epidural needle enters epidural space
- Spinal needle is threaded through epidural needle and then punctures dura and enters subarachnoid space
- Spinal Anesthesia (intrathecal Analgesic or Anesthetic) is injected into subarachnoid space
- Spinal needle is withdrawn
- Epidural catheter is advanced within the epidural space
- Epidural catheter is left in place for further Epidural Anesthesia and its needle is withdrawn
- Lower dose Anesthetic (bupivicaine or ropivicaine) with or without Fentanyl (Duragesic)
- Anesthetic only (without Opioid) in subarachnoid space results in fewer side effects (see below)
- However, adding Opioid offers faster Analgesic onset and lower Anesthetic dosing
- Benefits
- Faster onset of pain relief with decreased rescue Anesthesia
- Fewer assisted vaginal deliveries
- Allows patients to remain ambulatory despite epidural
- Similar pain relief to standard epidural
- Shorter Second Stage of Labor
- Adverse Effects
- Increased maternal Pruritus and Nausea
- Nonreassuring Fetal Heart Tones
- Adverse effects are increased with Opioid and Anesthetic are used in contrast to Anesthetic alone
- Reference
VII. Adverse Effects: General
- Risks of maternal Hypotension (occurs in up to one third of patients)
- Preadministration of Normal Saline 500 to 1000 cc may prevent Hypotension in Epidural Anesthesia
- Systemic injection
- Fever
- Spinal Headache
- Nerve injury
- High Neuraxial Block (excessive analgesia) with cardiorespiratory compromise (1 in 4000)
- Respiratory arrest (1 in 10,000)
- Spinal catheter placement (1 in 15,000)
VIII. Adverse Effects: Labor progress and outcomes
- Higher risk of Labor Dystocia if Cervix <5 cm in early studies
- Early epidural: 21% Cesarean Section rate
- Late epidural: 11% Cesarean Section rate
- Lieberman (1995) Perinatal Confer, John's Hopkins
- More recent study shows no benefit to epidural delay
- Labor slowed only between 4-5 cm (not <4 cm)
- No increase in ceserean with early epidural
- Vahratian (2004) Am J Obstet Gynecol 191:259-65 [PubMed]
- Most recent data shows no increased rate of Assisted Delivery or cesarean delivery regardless of labor stage
- Measures to reduce first-stage of labor time in Epidural Anesthesia
- Peanut ball with regular position changes reduces First Stage of Labor time by 87 minutes
- Delgado (2022) Obstet Gynaecol 42(5): 726-33 [PubMed]