In a pregnant woman in active labor, how should she be prepared and is she eligible for epidural or spinal anesthesia?

Preparing a Patient in Labor for Epidural or Spinal Anesthesia

Yes, she can and should be offered epidural or spinal anesthesia regardless of her cervical dilation, and preparation focuses on establishing IV access, ensuring aspiration prophylaxis, and performing a focused assessment rather than waiting for arbitrary labor milestones. 1

Eligibility for Neuraxial Anesthesia

Neuraxial analgesia should be offered on an individualized basis regardless of cervical dilation—there is no minimum dilation threshold required. 1 The outdated practice of withholding epidural until 4-5 cm dilation has been definitively abandoned by current guidelines.

• Patients in early labor (less than 5 cm dilation) should be offered neuraxial analgesia when the service is available. 1
• Reassure the patient that epidural analgesia does not increase the incidence of cesarean delivery. 1, 2
• The timing should be based on the patient's request for pain relief, not on achieving arbitrary cervical measurements. 2

Pre-Procedure Preparation Steps

1. Focused Assessment

Perform a directed history and physical examination, including airway and back examination when neuraxial anesthesia is planned. 1

Key elements to assess:

• Airway examination (mouth opening, neck mobility, thyromental distance) 1
• Back examination for anatomical landmarks, prior surgery, or spinal abnormalities 1
• Recognition of significant anesthetic or obstetric risk factors should prompt consultation between obstetrician and anesthesiologist 1

2. Laboratory Testing

Routine intrapartum platelet count is not required for healthy, uncomplicated laboring patients. 1

However:

• For suspected preeclampsia or coagulopathy, obtain an intrapartum platelet count before neuraxial placement 1
• An intrapartum blood type and screen should be obtained for all parturients 1

3. Intravenous Access

Establish intravenous access before initiating neuraxial analgesia and maintain it throughout the duration of the neuraxial technique. 1

• Administration of a fixed volume of intravenous fluid is NOT required before neuraxial analgesia is initiated 1—this represents an important change from older practice patterns

4. Aspiration Prophylaxis

For uncomplicated laboring patients:

• Moderate amounts of clear liquids may be allowed 1
• Solid foods should be avoided 1

For patients with additional aspiration risk factors (morbid obesity, diabetes mellitus, difficult airway) or those at increased risk for operative delivery (nonreassuring fetal heart rate pattern), further oral intake restrictions should be determined on a case-by-case basis. 1

Before surgical procedures (cesarean delivery), consider timely administration of nonparticulate antacids, H₂-receptor antagonists, and/or metoclopramide for aspiration prophylaxis. 1

5. Fetal Monitoring

Perianesthetic recording of the fetal heart rate reduces fetal and neonatal complications. 1

• Continuous fetal heart-rate monitoring should be performed for the first 30 minutes after neuraxial initiation 3

Special Populations Requiring Early Epidural Placement

Consider early insertion of a neuraxial catheter for obstetric or anesthetic indications to reduce the need for general anesthesia if an emergent procedure becomes necessary. 1, 2

Specific indications include:

• Twin gestation 1, 2
• Preeclampsia 1, 2
• Anticipated difficult airway 1, 2
• Obesity 1, 2
• Vaginal birth after cesarean (VBAC) attempt 1, 2

In these cases, insertion of the neuraxial catheter may precede the onset of labor or the patient's request for labor analgesia. 1

Technique Selection

Continuous Epidural Infusion

Continuous epidural infusion may be used for effective analgesia for labor and delivery. 1, 2

• When continuous epidural infusion of local anesthetic is selected, an opioid should be added to reduce the concentration of local anesthetic, improve the quality of analgesia, and minimize motor block 1, 2
• Use dilute concentrations of local anesthetics (0.1%-0.125% bupivacaine or ropivacaine) with opioids (fentanyl 2-2.5 µg/mL) to produce as little motor block as possible 1, 3, 2

Single-Injection Spinal

Single-injection spinal opioids with or without local anesthetics may be used to provide effective, although time-limited (approximately 1.5-2 hours), analgesia for labor when spontaneous vaginal delivery is anticipated. 1, 3

• If labor duration is anticipated to be longer than the analgesic effects of the spinal drugs chosen, or if there is a reasonable possibility of operative delivery, then a catheter technique should be considered instead of a single-injection technique 1, 3
• Use pencil-point spinal needles instead of cutting-bevel spinal needles to minimize the risk of postdural puncture headache 1, 3

Combined Spinal-Epidural (CSE)

CSE provides faster onset of analgesia (3-5 minutes) and is especially indicated when cervical dilation is ≥6 cm or when immediate pain relief is required. 3

• Intrathecal dosing: bupivacaine 1.25-2.5 mg combined with fentanyl 12.5-25 µg 3

Post-Placement Monitoring

Immediate monitoring requirements:

• Measure maternal blood pressure every 5 minutes for at least the first 15 minutes after any epidural bolus 3
• An anesthetist must remain present with the patient for at least 10 minutes following the initial bolus 3
• Continuous fetal heart-rate monitoring for the first 30 minutes 3

Ongoing monitoring throughout labor:

• Assess motor block (leg strength using straight-leg-raising test) hourly to detect excessive spinal involvement 3
• Assess sensory block level hourly alongside motor assessment 3
• Inability to raise the heel against gravity signals possible catheter misplacement or neurologic injury 3

Resources and Equipment

When neuraxial techniques that include local anesthetics are chosen, appropriate resources for the treatment of complications (hypotension, systemic toxicity, high spinal anesthesia) should be available. 1

• If an opioid is added, treatments for related complications (pruritus, nausea, respiratory depression) should be available 1
• Basic and advanced life-support equipment should be immediately available in the operative area of labor and delivery units 1

Common Pitfalls to Avoid

• Do not withhold neuraxial analgesia based on arbitrary cervical dilation thresholds—this outdated practice delays effective pain relief without benefit 1, 3, 2
• Do not require a fluid bolus before epidural placement—this is no longer recommended for uncomplicated patients 1
• Do not rely exclusively on sensory-block monitoring—incorporate hourly motor-block assessment to detect potential spinal cord compromise 3
• Avoid using high-concentration local anesthetic solutions without opioids—this increases motor block without improving analgesia 1, 3
• Do not choose single-injection spinal technique if labor is expected to last longer than 1.5-2 hours or if operative delivery is possible—use a catheter technique instead 1, 3

Consent Considerations

Drugs, fatigue, pain, or anxiety may compromise capacity but do not necessarily lead to incapacity unless the degree of compromise is severe. 1

• Labor is the wrong time to burden women with excessive information; every obstetric unit must provide information about pain relief and anesthesia in early pregnancy 1
• The patient must still be provided with appropriate information at the time of the procedure, and the details must be documented 1
• Women who have capacity and request epidural analgesia during labor, despite recording a refusal in their birth plan, must have their request respected 1