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Neuraxial analgesia for labor and delivery (including instrumental delivery)

Neuraxial analgesia for labor and delivery (including instrumental delivery)
Literature review current through: Jan 2024.
This topic last updated: Jan 24, 2024.

INTRODUCTION — Neuraxial analgesia is the most effective and most commonly used therapy for pain relief during labor and delivery. Epidural, combined spinal-epidural (CSE), and other central neuraxial techniques, including dural puncture epidural (DPE), single-shot spinal, and continuous spinal analgesia, are among the many options available to alleviate the pain of childbirth. In most cases, these techniques provide excellent analgesia with minimal risk to both mother and fetus.

This topic will discuss the indications, common techniques, and drugs used for neuraxial labor analgesia. The pain pathways applicable to labor and delivery, other pharmacologic methods for control of labor pain, neuraxial techniques, and adverse effects of neuraxial block are discussed in detail separately. (See "Pharmacologic management of pain during labor and delivery", section on 'Pain pathways' and "Pharmacologic management of pain during labor and delivery", section on 'Adverse consequences of labor pain' and "Adverse effects of neuraxial analgesia and anesthesia for obstetrics" and "Spinal anesthesia: Technique" and "Epidural and combined spinal-epidural anesthesia: Techniques".)

INDICATIONS FOR NEURAXIAL ANALGESIA — Neuraxial labor analgesia may be performed to relieve the pain of labor and to provide an in-situ epidural catheter for rapid conversion to surgical anesthesia for operative delivery, should it become necessary.

Pain relief — Neuraxial analgesia is appropriate for laboring women regardless of parity, cervical dilation, and fetal station, unless there is a contraindication [1]. The techniques are usually easily performed, life-threatening complications are rare, and side effects such as pruritus and hypotension are transient or easily treated. (See "Adverse effects of neuraxial analgesia and anesthesia for obstetrics" and "Serious neurologic complications of neuraxial anesthesia procedures in obstetric patients".)

The following general considerations apply to neuraxial analgesia for labor:

The American College of Obstetricians and Gynecologists (ACOG) and the American Society of Anesthesiologists (ASA) concur that maternal request is sufficient indication for pain relief during labor, barring a medical contraindication [1-3].

Neuraxial analgesia must block T10 to L1 for the first stage of labor and extend to S2 to S4 during the late first stage and second stage of labor.

Neuraxial analgesia may be initiated at any stage during labor, including in early labor and at full cervical dilation.

Labor often progresses more quickly for parous patients than for nulliparous patients and, for all parturients, may be more intense at the later stages of cervical dilation and during the second stage of labor. Parous patients may require more rapid onset of neuraxial block that covers the sacral nerve roots.

Pain relief may improve the course of labor by blunting the adverse maternal cardiovascular, respiratory, and gastrointestinal effects of catecholamines. The provision of adequate labor analgesia may also improve uteroplacental perfusion and decrease the incidence of postpartum depression and persistent postpartum pain. (See "Pharmacologic management of pain during labor and delivery", section on 'Adverse consequences of labor pain'.)

Absolute contraindications to neuraxial labor analgesia are rare. The risks and benefits of initiation of neuraxial blockade in laboring women must be considered on a case-by-case basis. Some relative contraindications include coagulopathy, infection of the lower back, and increased intracranial pressure due to an intracranial lesion. (See "Neuraxial anesthesia/analgesia techniques in the patient receiving anticoagulant or antiplatelet medication" and "Obstetric and nonobstetric anesthesia for patients with neurologic disorders", section on 'Brain tumors'.)

Studies of the effects of neuraxial analgesia on the risk of cesarean delivery, the length of labor, breastfeeding success, and preexisting or new-onset low back pain have been largely reassuring. (See "Adverse effects of neuraxial analgesia and anesthesia for obstetrics", section on 'Effects on the progress and outcome of labor'.)

Preparation for surgical anesthesia — Early administration of neuraxial labor analgesia should be considered for both high-risk women and for laboring women who are likely to require surgical anesthesia for operative delivery. The goal for early epidural placement in this setting is to reduce the need for general anesthesia for an unplanned, cesarean delivery or for anesthesia during the management of postpartum hemorrhage (PPH) [2]. We usually place a neuraxial catheter early in labor for patients with the following conditions:

Twin gestation

Preeclampsia

Trial of labor after cesarean delivery

Category II fetal heart rate (FHR) tracing during attempted vaginal delivery (see "Intrapartum category I, II, and III fetal heart rate tracings: Management", section on 'Category II pattern (Indeterminate)')

History of prior PPH

Obesity (body mass index [BMI] >40 kg/m2) with challenging anatomic landmarks for neuraxial procedures or with obstructive sleep apnea

Anticipated or known difficult airway

History (in patient or biologic relative) of malignant hyperthermia

Once a neuraxial catheter is in place, it should be dosed for labor analgesia and then reassessed frequently to ensure functionality, with a low threshold to replace a poorly functioning catheter. Early administration of local anesthetic (LA) provides information on the functionality of the catheter and also provides an initial block, which can be augmented for cesarean delivery anesthesia. Risk factors for the failed conversion of neuraxial labor analgesia to cesarean delivery anesthesia include one to two unscheduled top-ups during labor, greater urgency for the cesarean delivery, and provision of care by a non-obstetric anesthesiologist [4,5].

PREPARATION FOR NEURAXIAL LABOR ANALGESIA — Preparation for neuraxial labor analgesia should include the following:

Preanesthesia evaluation – Perform a focused preanesthesia evaluation, including the patient's obstetric, anesthetic, and general medical history. Perform a targeted physical examination, including vital signs, airway, heart, lungs, and back.

Laboratory evaluation Routine lab work is not required prior to initiation of neuraxial blockade in healthy parturients.

A platelet count may be indicated in selected patients, including those with a known etiology for thrombocytopenia (eg, with gestational thrombocytopenia, immune thrombocytopenia, thrombocytopenia associated with hypertensive disorders of pregnancy), those receiving heparin therapy for more than four days, and those with a bleeding history and/or signs of disseminated intravascular coagulation (algorithm 1) [6,7]. (See "Neuraxial anesthesia/analgesia techniques in the patient receiving anticoagulant or antiplatelet medication", section on 'Unfractionated heparin (UFH)' and "Adverse effects of neuraxial analgesia and anesthesia for obstetrics", section on 'Spinal epidural hematoma'.)

Type and screen or crossmatch is not necessary in healthy patients; sending a blood sample to the blood bank should be considered for parturients at risk of postpartum hemorrhage (PPH) or for those at risk of having blood cell antibodies [2].

Informed consent – Informed consent should include a discussion of the risks and benefits of available options for labor analgesia and anesthesia for cesarean delivery, as well as information about the anesthesiologist's role in the management of obstetric emergencies. This and any patient concerns or questions should be discussed as early as possible, preferably upon admission, early in the intrapartum course, or during an antenatal obstetric anesthesia consult.

Establish intravenous access – All patients undergoing neuraxial block should have vascular access for fluid and drug administration.

Equipment check Ensure availability of emergency airway equipment and resuscitation medications. Lipid emulsion (20 percent) should be immediately available for treatment of local anesthetic systemic toxicity (LAST) (table 1). (See "Local anesthetic systemic toxicity", section on 'Management of LAST'.)

Monitors – Apply maternal monitors (ie, blood pressure [BP] cuff and pulse oximeter) and fetal heart rate (FHR) monitors, as indicated by obstetric, nursing, and institutional policies. (See 'Monitoring during neuraxial labor analgesia' below.)

Time out – Perform a preprocedure "time-out," including patient identification, confirmation of correct procedure, verification of consent, dose and timing of drugs administered for thromboprophylaxis, and a review of any concerns about coagulation status.

Aspiration prophylaxis Oral intake during labor is limited to clear liquids, primarily to reduce the risk of aspiration if general anesthesia is required for cesarean delivery. We do not routinely administer pharmacologic aspiration prophylaxis to laboring patients prior to initiation of neuraxial blockade. However, it is reasonable to administer sodium citrate-citric acid, 30 mL orally, for patients at risk for emergency conversion to cesarean delivery (eg, patients with category 2 tracing). (See "Labor and delivery: Management of the normal first stage", section on 'Oral intake'.)

Aseptic technique – Neuraxial anesthesia should always be performed using strict aseptic technique. (See "Spinal anesthesia: Technique", section on 'Aseptic technique'.)

PRE-PROCEDURAL ULTRASOUND — Pre-procedural neuraxial ultrasound may be used to identify the interspace for needle placement and to estimate the distance from the skin to the epidural space. We use ultrasound to build proficiency and find it particularly useful for patients with scoliosis, prior back surgery, or potentially difficult anatomic landmarks.

A number of studies have evaluated the use of preprocedural ultrasound in obstetric patients. A 2021 meta-analysis of 22 randomized trials that compared preprocedural ultrasound with landmark palpation in obstetric patients found that ultrasound increased the first-pass success rate in patients with difficult anatomy, but not in patients with easy-to-palpate landmarks [8]. Time to complete the neuraxial procedure was similar between groups for patients with difficult anatomy, whereas the procedure took approximately one minute longer with ultrasound in patients with easy anatomy. Complications such as postpartum backpain and headache were decreased with preprocedural ultrasound. Overall quality of the evidence was low to very low.

Ultrasound may be less helpful for experienced practitioners and for patients with easily palpable landmarks [9]. However, routine use of ultrasound is recommended to build technical proficiency. Neuraxial ultrasound for anesthesia is discussed in detail separately. (See "Ultrasound guidance for neuraxial anesthesia techniques".)

PATIENT POSITIONING — Optimal positioning is critical to the success of neuraxial procedures, and both the sitting and lateral decubitus positions are used effectively. (See "Epidural and combined spinal-epidural anesthesia: Techniques", section on 'Positioning for epidural procedure'.)

We recommend using the lateral position in specific clinical circumstances (eg, in the setting of advanced cervical dilation, for patients with vasovagal syncope, or for those at increased risk of cord prolapse). Initiation of neuraxial block in the lateral position may facilitate fetal heart rate (FHR) monitoring, reduce the risk of intravascular placement of the epidural catheter, enhance patient comfort during the procedure, and require less assistance from skilled support personnel. The sitting position may be particularly useful for larger patients in whom the bony landmarks may be difficult to feel.

MONITORING DURING NEURAXIAL LABOR ANALGESIA — During initiation and maintenance of neuraxial labor analgesia, the following monitors should be applied:

During initiation of neuraxial analgesia Maternal oxygen saturation and heart rate (HR) should be measured continuously with the pulse oximeter, and blood pressure (BP) should be measured every five minutes for at least 15 to 20 minutes, or until the patient is hemodynamically stable. Fetal HR (FHR) should be monitored at minimum before and after initiation of neuraxial analgesia and according to institutional protocol.

During maintenance of neuraxial labor analgesia – Maternal BP should be measured every 30 minutes, or more frequently in the setting of maternal hypotension and during category 2 and 3 FHR tracings. FHR should be monitored as per American College of Obstetricians and Gynecologists (ACOG) and institutional protocol. Pain control, motor function, and sensory level, as needed, should be assessed at regular intervals to ensure a properly functioning block. We assess the patient's vital signs and pain assessment, as well as the FHR, every one to two hours.

NEURAXIAL TECHNIQUES

Choice of technique — Continuous epidural and combined spinal-epidural (CSE) are the most commonly used neuraxial techniques for labor analgesia. Many obstetric anesthesiologists use the CSE technique for all uncomplicated laboring patients. Dural puncture epidural (DPE) may be increasingly used for labor analgesia. Single-shot and continuous spinal techniques may be used in selected clinical scenarios. Although the choice of technique must be individualized, the following general considerations apply:

Spinal techniques (ie, the spinal portion of the CSE, single-shot spinal, continuous spinal) provide more rapid onset of symmetric analgesia, including sacral analgesia, than a conventional epidural technique. Single-shot spinal and continuous spinal are rarely used.

Continuous techniques (ie, continuous epidural, the catheter component of the CSE, continuous spinal) provide analgesia throughout labor and delivery, with the option to convert rapidly to surgical anesthesia for operative delivery.

Although the functionality of the epidural catheter is not known at the onset of the block with the CSE technique, the evidence suggests that epidural catheters placed during CSE (and DPE) procedures are at least as reliable, or more reliable, than stand-alone epidurals [10-13].

Epidural analgesia requires higher drug doses than spinal analgesia. In current clinical practice, low concentrations of local anesthetic (LA) are commonly used for labor epidural solutions (eg, 0.0625 to 0.1% bupivacaine or 0.08 to 0.1% ropivacaine). With these low-concentration epidural solutions, the risk of systemic toxicity is very low, even with inadvertent intravascular injection. However, high or total spinal anesthesia can occur if an epidural dose of medication is administered in an unrecognized spinal catheter.

DPE and CSE may be used to help confirm the position of the epidural needle tip when loss of resistance is equivocal. (See 'Dural puncture epidural analgesia' below.)

A continuous spinal catheter, the least common of the neuraxial techniques, may be placed after accidental dural puncture during a routine epidural procedure by threading the catheter directly into the intrathecal space. It is essential to label the catheter as spinal in order to avoid the injection of high doses of local anesthesia, which may lead to a high spinal. Alternatively, smaller gauge needles and catheters are made for this purpose, but are not routinely used in the United States.

Epidural versus CSE — The choice between conventional epidural and combined spinal-epidural (CSE) techniques is often determined by the clinical situation, institutional norms, available equipment, and clinician preference.

CSE techniques may provide some benefits over traditional labor epidurals, including faster onset of analgesia (three to five minutes) [14] and reduced need for rescue analgesia. In addition, a meta-analysis of randomized controlled trials reported a lower risk of unilateral block with CSE, without a difference in the need for catheter replacement or unscheduled top-ups [10]. Despite the dural puncture with the CSE technique, the risk of post dural puncture headache (PDPH) does not appear to be increased. CSE technique has, however, been associated with a higher incidence of pruritus and fetal bradycardia than epidural labor analgesia [14]. (See "Adverse effects of neuraxial analgesia and anesthesia for obstetrics".)

Epidural analgesia technique — For epidural analgesia or anesthesia, an epidural needle is positioned below the L2 to L3 lumbar interspace. An epidural catheter is threaded through the needle into the epidural space; the needle is removed, and the catheter is secured and connected to an infusion pump system.

Epidural anesthesia equipment and the epidural technique are discussed in detail separately. (See "Epidural and combined spinal-epidural anesthesia: Techniques", section on 'Epidural anesthesia technique'.)

The epidural test dose in obstetrics — A test dose may be administered through the epidural catheter to evaluate for unintentional intravascular or subarachnoid catheter placement. A commonly used test dose solution consists of 3 mL of lidocaine 1.5% (to test for subarachnoid injection) with 5 mcg/mL of epinephrine (to test for intravascular injection). Motor block within three to five minutes [15] is suggestive of subarachnoid catheter placement, while an increase in maternal HR of 20 percent or greater (or an increase in HR of 10 to 25 beats/minute [bpm]) within one minute is suggestive of an intravascular catheter.

The sensitivity, specificity, and safety of the intravascular and intrathecal test dose using LAs and epinephrine have been questioned [16], and the use of a test dose varies among obstetric anesthesiologists. As examples, one author of this topic routinely uses a test dose, and the other does not.

If the test dose is used, it should not be administered during a contraction. In laboring patients, an increase in heart rate (HR) after the test dose may be a physiologic response to a painful contraction, resulting in a false-positive interpretation and unnecessary catheter removal and re-instrumentation. To evaluate for intrathecal injection, wait up to five minutes to confirm that the patient is not developing a motor block.

Caution should be used when administering an epinephrine-containing test dose in patients with hypertension or with uteroplacental insufficiency, as systemic epinephrine can precipitate profound hypertension and can theoretically decrease uteroplacental perfusion in these patients [17]. Some UpToDate contributors avoid epinephrine containing test doses in such patients.

Alternative measures can reduce the risk of intravascular and intrathecal catheter placement and associated complications, including the following:

Use flexible wire-reinforced epidural catheters to reduce the incidence of epidural vein cannulation [18].

Use dilute LA solutions for labor (eg, bupivacaine 0.0625 to 0.1% or ropivacaine 0.08 to 0.1%), thereby reducing the total dose of LA should intravascular or intrathecal injection occur. (See 'Epidural analgesia drug choice' below.)

Treat every injection (ie, for initiation of epidural analgesia, top-ups, and dosing for cesarean delivery) as a test dose: inject in ≤ 5 mL increments and aspirate prior to each injection, except when administering alkalinized 3% 2-chloroprocaine for emergency cesarean delivery (aspirate prior to injection). Aspiration of an epidural catheter for blood or CSF after insertion helps detect misplaced catheters [19].

Replace catheters that result in irregular block or inadequate analgesia.

No test dose or safety measure is 100 percent effective at preventing intravascular or intrathecal injection of LA. Serious complications have been reported in obstetric patients as a result of unrecognized intrathecal catheters [19], even after an uneventful test dose. Therefore, awareness of potential complications, maternal and fetal monitoring, and availability of emergency equipment and lipid emulsion (20 percent) for treatment of local anesthetic systemic toxicity (LAST) are mandatory on labor and delivery floors. (See 'Preparation for neuraxial labor analgesia' above and "Local anesthetic systemic toxicity".)

Initiation of epidural analgesia — Labor epidural analgesia is established by the incremental injection of LA, most commonly in combination with opioid and, less commonly, with other adjuvant medications. (See 'Epidural analgesia drug choice' below.)

Once the catheter has been placed and secured, our procedure is as follows:

After negative aspiration, initiate the block by injecting a premixed epidural solution (eg, bupivacaine 0.0625 to 0.1% with 2 mcg/mL fentanyl or ropivacaine 0.08 to 0.1% with 2 mcg/mL fentanyl) in 5 mL increments, with aspiration between injections, for a total of 10 to 20 mL. (See 'Epidural analgesia drug choice' below.)

Alternatively, the block can be initiated with a lower volume of more concentrated LA (eg, 6 to 10 mL of bupivacaine 0.125% or ropivacaine 0.2%), combined with opioid (eg, fentanyl 50 to 100 mcg or sufentanil 5 to 10 mcg), with or without a test dose. However, these doses may result in more motor block than dosing with more dilute solutions [20,21] (table 2).

Measure maternal blood pressure (BP) every five minutes for at least 15 to 20 minutes, until stable, while assessing fetal HR (FHR) and pain relief.

Initiate maintenance labor epidural analgesia. (See 'Maintenance of labor epidural analgesia' below.)

Patients are typically positioned with left uterine displacement for up to 30 minutes after initiation of epidural blockade to alleviate aortocaval compression, although there is a lack of definitive data to support this practice [22]. (See "Anesthesia for cesarean delivery", section on 'Intraoperative positioning'.)

Maintenance of labor epidural analgesia — Unless delivery occurs soon after epidural initiation, labor epidural analgesia is most commonly maintained by continuous and/or intermittent administration of a solution of dilute LA with opioid, often the same solution that is used to initiate epidural analgesia. (See 'Epidural analgesia drug choice' below.)

Epidural analgesia should be continued throughout the second and third stages of labor. Historically, it was not uncommon for the obstetrician to request discontinuation of epidural analgesia late in labor in order to improve maternal expulsive efforts and thereby reduce the need for operative delivery (ie, forceps or vacuum). This practice is not supported by the literature or practice guidelines [23]. (See "Adverse effects of neuraxial analgesia and anesthesia for obstetrics", section on 'Effects on the progress and outcome of labor'.)

Modes of drug administration — For maintenance of labor epidural analgesia, the epidural solution is usually administered by infusion pump. The drug can be given by continuous infusion; by patient-controlled epidural analgesia (PCEA), with or without background continuous infusion; or by programmed intermittent bolus (PIEB), with or without PCEA. Clinician-administered boluses (ie, top-ups) may be required for breakthrough pain.

Continuous epidural infusion techniques — Continuous epidural infusion (CEI) reduces clinician workload, decreases fluctuations in pain, contributes to greater patient satisfaction, and may reduce the risks of LAST and hemodynamic instability when compared with large, manual boluses of LAs [24,25]. CEI does not eliminate motor block or the need for rescue boluses.

Patient-controlled epidural anesthesia — PCEA is a technique that permits the patient to self-administer a bolus of epidural drug solution, with or without a continuous background infusion or programmed, intermittent pump-delivered boluses. PCEA with continuous background infusion may reduce the need for unscheduled clinician interventions and improve maternal analgesia when compared with PCEA alone [26]. The incidence of motor block with PCEA appears to be related to the concentration of LA and, perhaps, to the presence or absence of a continuous background infusion. In a meta-analysis of nine randomized controlled trials, there was a lower incidence of motor block when PCEA (without background infusion) was used when compared with CEI alone [27]. Because patient participation is required, cultural factors, patient expectations, and patient training influence efficacy [28]. Optimal PCEA settings have not been determined. Common regimens include a variety of background infusions, with the following PCEA settings:

8 to 10 mL of 0.0625% bupivacaine with 2 mcg/mL fentanyl every 10 minutes, or

6 to 8 mL of 0.1% bupivacaine with 2 mcg/mL fentanyl every 15 minutes, or

10 mL of 0.1% ropivacaine with 2 mcg/mL fentanyl every 10 to 15 minutes

New pump technologies continue to be developed, including a disposable PCEA device [29] and a computer-integrated infusion pump (CIPCEA) that modifies the background infusion rate based on the patient's bolus dose requirements during the previous hour [30,31].

Programmed intermittent epidural bolus — Programmed intermittent epidural bolus (PIEB) allows the infusion pump to deliver epidural boluses at predetermined intervals. A meta-analysis of 27 studies including 3133 patients reported superior pain control during the first four hours after epidural initiation, reduced risk of breakthrough pain, and a trend toward reduced motor weakness with the use of PIEB versus CEI [32]. No difference was found with other side effects (eg, hypotension, pruritus, nausea). The mechanism for improved analgesia with PIEB may relate to the high injectate pressure associated with the automated bolus technique and the favorable spread of large volumes of epidural solution.

One study found equivalent labor pain control with PIEB and PCEA if similarly large bolus doses were programmed. In this multicenter trial, 336 nulliparous patients who had CSE for labor analgesia were randomly assigned to epidural maintenance with either PCEA (10 mL bolus, 30 minute lockout) or PIEB (10 mL bolus each hour, with additional 5 mL PCEA bolus with 30 minute lockout), both using ropivacaine 0.12% with sufentanil 0.75 mcg/mL [33]. Breakthrough pain, pain scores, motor block, maternal satisfaction, and neonatal outcomes were similar in the two groups. Mean ropivacaine consumption was lower in the PCEA group (63.3 versus 78.5 mg).

An increasing number of institutions are using PIEB with PCEA with low-concentration LA/opioid epidural solutions (eg, 0.0625% bupivacaine with fentanyl 2 mcg/mL or 0.1% ropivacaine with sufentanil 0.3 mcg/mL). The pump is commonly programmed with a pump-bolus interval of 5 to 10 mL every 30 to 60 minutes, starting after CSE or epidural placement, in addition to a PCEA. A smaller PIEB bolus dose is programmed when shorter time intervals are selected.

Optimal settings for PIEB have not been determined. Examples of relevant studies include the following:

In one study, 190 parturients were randomized to one of three PIEB regimens using bupivacaine 0.0625% with fentanyl 1.95 mcg/mL (2.5 mL every 15 minutes, 5 mL every 30 minutes, or 10 mL every 60 minutes) after CSE and a lidocaine 1.5% with epinephrine test dose [34]. Extending the programmed bolus interval and increasing the volume slightly reduced bupivacaine consumption without compromising patient comfort or satisfaction.

Another study found that the PIEB volume of 0.0625% bupivacaine with fentanyl 2 mcg/mL could not be reduced below 10 mL without compromising the quality of analgesia when using a 40-minute time interval [35]. These settings (10 mL boluses at 40-minute intervals) provided good quality of analgesia without the use of supplementary PCEA boluses. However, a high proportion of patients developed sensory block above T6.

Another small study determined that the optimal interval for 5 mL boluses of more concentrated local anesthetic for labor analgesia (0.125% bupivacaine with fentanyl 2 mcg/mL) was 35 minutes; similar to the previously mentioned study, over one-half of the patients who received effective analgesia had a sensory level above T6 [36].

It is essential to maintain vigilance for high spinal or total spinal block when using PIEB, particularly if concentrated local anesthetic is used, as the scheduled bolus doses are delivered at predetermined intervals (without patient participation). Rare cases of high block after inadvertent intrathecal catheter insertion or catheter migration have been reported [37].

CSE analgesia — Combined spinal-epidural (CSE) includes intrathecal injection of drugs to initiate spinal analgesia and insertion of an epidural catheter to allow maintenance of analgesia or conversion to surgical anesthesia. This technique combines the advantage of rapid onset (with the intrathecal injection) with the option to continue analgesia throughout labor and delivery and, if necessary, provide a means of rapid conversion to surgical anesthesia (through the epidural catheter).

CSE equipment — CSE is usually performed with a standard epidural needle and a long spinal needle. Alternatively, specialized equipment is available, including a double-lumen epidural needle, an epidural needle with a separate hole for the spinal needle, and epidural/spinal needle sets with hubs that lock together.

Typically, a roughly 4.7 to 5 inch (119 to 127 mm), small-gauge, pencil-point spinal needle (ie, 25- to 27-gauge) is used with a standard 8.89 cm (3.5 inch) epidural needle. In the rare instance in which a longer epidural needle is used, an even longer spinal needle is required.

CSE technique — As for single-shot spinal anesthesia, CSE is performed below the L2 to L3 interspace to avoid the spinal cord. The intercristal line (ie, Tuffier's line) is an unreliable surface anatomic landmark in the pregnant patient, and studies show that even experienced anesthesiologists misidentify the lumbar interspace by palpation, not uncommonly being at least one or two interspaces higher than anticipated [38-40]. Therefore, we recommend choosing a lower lumbar interspace with palpation or using ultrasound for better precision. (See "Spinal anesthesia: Technique", section on 'Anatomy'.)

CSE is usually performed with a needle-through-needle technique. The epidural needle is sited with the tip in the epidural space; a long spinal needle is then inserted through the epidural needle to puncture the dura and arachnoid membranes. It is helpful to ask the patient to administer a bolus (or to have the pump administer a bolus) within 30 minutes to an hour after the spinal medication has been administered, even in the absence of pain, to provide a smooth transition to the epidural block. Combined spinal epidural anesthesia technique is discussed in detail separately. (See "Epidural and combined spinal-epidural anesthesia: Techniques", section on 'Combined spinal-epidural anesthesia'.)

Single-shot spinal analgesia — A single-shot spinal technique involves spinal (ie, subarachnoid, intrathecal) injection of low dose medication (eg, 1.25 to 3 mg isobaric bupivacaine with 10 to 15 mcg fentanyl) for labor analgesia without placement of an epidural catheter. Onset of analgesia is rapid, but the duration is limited by the duration of action of the drug injected. (See 'Intrathecal analgesia drug choice' below.)

Single-shot spinal may be indicated in selected clinical circumstances, including the following:

The multiparous parturient in rapidly progressing, advanced labor may benefit from fast onset of spinal analgesia, without the need for extended (ie, epidural) block, although a catheter-based technique (ie, CSE) may be preferable for unexpectedly prolonged labor or postpartum complications.

Spinal injection may be feasible when epidural catheter placement is expected or found to be difficult (eg, in patients with abnormal anatomy with or without extensive spinal surgery). In this setting, repeated spinal injections may be used throughout labor or an epidural procedure may be reattempted once the patient is comfortable.

For difficult spinal placement in patients with obesity, an epidural Tuohy needle can be used as the introducer needle, paired with a long spinal needle, as in the CSE technique. Ligamentous tissue and other landmarks may be easier to reach and feel with the Tuohy needle compared with the typical short spinal introducer or the smaller-gauge spinal needle. Neuraxial ultrasound may also be helpful in this setting.

Spinal anesthesia technique is discussed separately. (See "Spinal anesthesia: Technique", section on 'Anatomy' and "Spinal anesthesia: Technique", section on 'Technique'.)

Continuous spinal analgesia — The continuous spinal technique combines the rapid onset of dense, symmetric analgesia with the ability to incrementally extend analgesia and convert to surgical anesthesia [41]. Continuous spinal labor analgesia is rarely the first choice technique because of a high incidence of PDPH with currently available equipment and a historical association with cauda equina syndrome with the older, smaller-gauge microcatheters. In the United States, the continuous spinal technique is occasionally used for parturients in whom epidural placement may be difficult or ineffective for anatomic reasons (eg, patients who have had extensive spinal surgery). The continuous spinal technique is also a reasonable option after an accidental dural puncture (ADP) during attempted epidural placement.

Continuous spinal equipment Continuous spinal is usually performed with the 17- or 18-gauge epidural needle and the 19- or 20-gauge epidural catheter that is used for epidural analgesia. Microcatheters (28- to 32-gauge) were associated with neurologic injury in the past, and the US Food and Drug Administration (FDA) banned their use in 1992. Spinal microcatheters (eg, 28-gauge) have again become available, although these catheters may be associated with a higher incidence of technical difficulty and catheter failure than epidural catheters [42].

Continuous spinal technique Continuous spinal technique is discussed separately. (See "Spinal anesthesia: Technique", section on 'Continuous spinal'.)

Mode of continuous spinal drug administration – The same LA/opioid combination solution used for epidural analgesia may be used for continuous spinal analgesia (eg, bupivacaine 0.0625 to 0.1% with 2 mcg/mL fentanyl or ropivacaine 0.08 to 0.1% with 2 mcg/mL fentanyl). The drug delivery mode most commonly used for spinal infusions is the continuous infusion, but the rate must be decreased to a range of approximately 1 to 5 mL/hour, depending on the concentration (eg, 1 mL/hour 0.1% bupivacaine, 3 mL/hour 0.0625% bupivacaine), and slowly adjusted as appropriate; the demand bolus option should be eliminated and PIEB should not be used. Most importantly, all members of the nursing, obstetric, and anesthesiology teams must be notified that the catheter is in the intrathecal space. We place "intrathecal" or "spinal" labels on the catheter, labor room door, infusion pump, and on the patient's chart.

Continuous spinal after dural puncture The decision to place a spinal catheter and administer continuous spinal analgesia after ADP should be individualized, and management varies among obstetric anesthesiologists. One author often places spinal catheters after ADP, whereas the other rarely places spinal catheters in this setting, unless the epidural attempt was extremely difficult. Evidence for the best strategy for neuraxial analgesia after ADP is inconclusive and is based on retrospective and observational studies. The effect of spinal catheter placement on the incidence of PDPH after ADP is discussed separately. (See "Post dural puncture headache", section on 'Prevention of PDPH after dural puncture'.)

Spinal catheters after ADP may provide less reliable labor analgesia, for unclear reasons. A review of 236 cases of ADP during epidural placement compared outcomes for patients managed with insertion of an intrathecal catheter with those who had a re-sited epidural catheter [43]. Intrathecal catheters were associated with a higher rate of failed analgesia requiring catheter replacement compared with re-sited epidurals (14 versus 2 percent). It is possible that lack of familiarity with the technique contributed to this finding.

The decision to place a spinal catheter or to re-site an epidural should be made quickly to avoid excessive egress of CSF from the large-bore epidural needle. If a new epidural procedure is performed immediately after an accidental dural puncture with a large-bore needle, there may be increased effect from the administered LA for the first several hours. A reduced initial dose and basal rate may be required. In practice, in this setting, we administer a test dose of 3 mL lidocaine with epinephrine or 5 mL of the epidural loading dose through the catheter and wait five minutes to gauge whether the patient has a higher-than-expected sensory and motor block. If not, we continue to administer the full loading dose in increments, as usual, assessing for motor and sensory block throughout. We then start the epidural infusion and titrate to effect.

Dural puncture epidural analgesia — The dural puncture epidural (DPE) technique is essentially a CSE technique without injection of intrathecal drugs. The dura is punctured as though performing a CSE technique, the spinal needle is removed after visualization of CSF, the epidural catheter is inserted, and epidural analgesia is initiated. The risk of PDPH does not appear to be increased compared to the standard epidural technique.

We sometimes use DPE to confirm epidural needle position when loss of resistance is equivocal. CSF flow through the spinal needle provides supportive evidence that the tip of the epidural needle is close to the dura and therefore likely in the epidural space. Attempting to thread the epidural catheter can also provide confirmation, although it is possible for any catheter (especially stiffer catheters) to thread along fascial planes or elsewhere outside of the epidural space.

We may consider using the DPE technique to initiate labor analgesia in patients who are likely to require conversion to cesarean delivery anesthesia or when replacing a failed catheter after one or two unscheduled top ups. Catheters placed with the DPE (or aCSE) technique are associated with more reliable conversion to surgical anesthesia and fewer catheter failures requiring replacement when compared with the standard epidural technique [44]. One study suggested that DPE may speed onset and improve block quality if the epidural is extended for surgical anesthesia, compared with conventional epidural. In this single institution trial, 136 patients scheduled for elective cesarean delivery were randomly assigned to receive DPE (using a 25 gauge spinal needle) versus conventional epidural placed approximately one hour prior to surgery, with epidural analgesia established and maintained with 0.0625% bupivacaine with fentanyl [45]. At the time of surgery, the epidural was extended with 3% chloroprocaine. The time to achieving a T6 sensory level was approximately 3 minutes faster and a composite outcome of block quality was better in patients who had DPE.

The suggested mechanism for improved analgesia with DPE is the leakage of drugs from the epidural space to the subarachnoid space.

The literature comparing the efficacy of DPE with other neuraxial analgesia techniques for labor is inconclusive [46-48]. Several factors, such as initial epidural bolus volume (ie, loading dose), concentration of LA in the epidural solution (ie, total epidural drug mass), size of the dural puncture, and mode of delivery (ie, CEI, PCEA, PIEB), may affect the rate of drug transfer through the dural puncture. Examples of relevant studies include the following:

Some studies that have compared DPE with continuous epidural analgesia show more symmetric analgesia, more extensive caudal spread, and/or faster onset of analgesia when a 25- or 26-gauge spinal needle was used to puncture the dura; similar outcomes have not been demonstrated with the use of a 27-gauge needle [49-53].

In one trial, 120 parturients in early labor were randomly assigned to receive a DPE, CSE, or standard epidural technique for labor analgesia [51]. Analgesia onset was faster for the CSE technique, the quality of analgesia was comparable with CSE and DPE, and both CSE and DPE provided superior analgesia compared with the standard epidural technique. There were fewer maternal and fetal adverse effects with DPE and epidural techniques than with the CSE technique (eg, pruritus, hypotension, uterine tachysystole and hypertonus).

In a randomized trial that compared PIEB labor analgesia after DPE versus conventional epidural analgesia in 132 parturients with obesity (body mass index [BMI] ≥ 35 kg/m2) there was no difference in the quality of analgesia between the two groups [48]. Conclusions from this study are limited by the small bolus volumes used, which may have obscured differences in outcomes [54].

CLINICIAN EPIDURAL TOP-UPS — Clinician-administered neuraxial bolus doses, or top-ups, may be required during labor despite an appropriate epidural loading dose and maintenance regimen. Breakthrough pain may result from obstetric or anesthetic issues, or a combination of the two. We use a systematic approach to the evaluation and management of pain during neuraxial labor analgesia, as follows:

Assess the pain The quality and location of pain may help determine the etiology and treatment. As examples, unilateral pain may suggest a problem with the epidural catheter, while increasing perineal pain may suggest progression of labor and inadequate sacral block. (See 'Pain relief' above.)

Assess the anesthetic The position of the epidural catheter and equipment function should be assessed. Confirm that the pump is appropriately delivering medication and that the patient is using self-administered boluses if the regimen includes PCEA.

Check the sensory level of the block – Assess the bilateral sensory level to cold stimulus (eg, using alcohol swab or ice) and sharp touch or ask the patient to indicate where there is breakthrough pain. A low level (ie, below T10) may suggest a problem with the catheter or inadequate dosing. Whereas the sensory level may be helpful, the dermatomal distribution may not always correspond with diffusely localized visceral pain, particularly during the first stage of labor. If pain persists despite an apparently adequate sensory level, a top up bolus may still be indicated.

Check catheter position Confirm that the epidural catheter looks as though it remains in the epidural space (eg, if loss of resistance was at 5 cm and the catheter was taped at 10 cm, confirm that the catheter remains at 10 cm at the skin). Subsequent steps depend on the catheter marking at the skin, as follows:

-If the catheter looks as though it has moved out at all, have a very low threshold to replace it.

-If the catheter looks as though it has moved in, then it has likely moved into the subcutaneous tissue rather than into the epidural space; do not change its position.

-If the catheter was originally inserted more than 6 cm and/or has advanced several cm, withdraw the catheter so that no more than 6 cm remain in the epidural space to minimize the risk of unilateral block (see below) and administer a top up bolus as described below.

-If the catheter appears to be appropriately placed and the sensory and motor block are equivocal, consider administering a more concentrated bolus dose (eg, 3 to 5 mL of 2% lidocaine), which should produce a sensory and motor block. If the bolus does not produce a block, replace the epidural catheter.

Top-up – Once proper catheter placement is confirmed by visual inspection, then, depending on the source and degree of pain, consider a clinician top-up, as follows:

-Mild pain – For a low sensory level with mild pain, either ask the patient to administer one or two PCEA boluses or provide a high-volume top-up with a dilute LA solution (8 to 10 mL), with or without an opioid, similar to the epidural solution. Following this, consider increasing the basal pump rate or decreasing the bolus dosing intervals.

-Moderate to severe pain – If the pain is moderate to severe, the patient is likely to need a more concentrated bolus than the infusion (eg, 6 to 10 mL 0.125% bupivacaine), especially if the infusion is dilute (eg, 0.0625% bupivacaine with 2 mcg/mL fentanyl).

-Unilateral pain – Place the patient in the lateral position with the uncomfortable side down. Consider withdrawing the catheter 1 cm, depending on how far the tip is in the epidural space, as discussed above. Administer a bolus (eg, 6 to 10 mL of 0.125% bupivacaine). If pain persists after 20 minutes, replace the epidural catheter.

-Pain after a CSE – A top-up may be required during a CSE technique once the intrathecal drug has worn off if the epidural component of analgesia has not yet been established. Consider an epidural bolus that is more concentrated than the labor epidural infusion for faster onset of analgesia (eg, 6 to 10 mL of 0.125% bupivacaine).

-Sacral pain – Sacral pain should raise the possibility that the patient is fully dilated and should prompt a discussion with the obstetrician or nurse for assessment or that the epidural has been inadvertently placed at a low thoracic level. The patient may feel better or worse when pushing and may or may not need replacement of the epidural catheter.

One option for clinician top-ups for sacral pain is 6 to 10 mL bolus of 0.125% bupivacaine or equipotent doses of ropivacaine, with or without 50 to 100 mcg of epidural fentanyl. In cases where the patient is still not comfortable, the obstetrician may choose to perform a pudendal block.

-Persistent pain after bolus – If the patient remains uncomfortable or there is an inadequate sensory level after a top-up, consider early replacement of the catheter. Once an epidural needs more than one or two unscheduled boluses, it is more likely to fail for both labor analgesia and for surgical anesthesia during cesarean delivery [4,5,11,55]. In our experience, repeating the procedure, particularly with either a CSE or DPE under these circumstances almost always results in improved analgesia.

DOSING A REPLACED EPIDURAL CATHETER — Dosing after repeating a neuraxial technique for a failed block depends on the patient’s preexisting analgesia.

If the patient has no pain relief and minimal sensory or motor block, then it is reasonable to use the full epidural loading dose or the usual combination of low-dose opioid with LA for the spinal portion of a CSE.

If there is a partial sensory or motor block, then administer a clinician top-up bolus according to the degree of pain and reassess. (See 'Clinician epidural top-ups' above.)

Bolus dosing (top-ups) for instrumental vaginal delivery is discussed separately. (See 'Analgesia for instrumental vaginal delivery' below.)

DRUG CHOICE FOR NEURAXIAL ANALGESIA — The drugs used for neuraxial labor analgesia techniques usually include a combination of dilute local anesthetic (LA) and lipid-soluble opioid. The American Society of Anesthesiologists (ASA) and the Society for Obstetric Anesthesia and Perinatology (SOAP) Practice Guidelines for Obstetric Anesthesia recommend using the lowest dose of LA and opioid that provides effective maternal analgesia and satisfaction with minimal adverse effects [2].

Goals for neuraxial drug choice — Goals for using the lowest effective total dose of LA and opioid include:

Minimize motor block, preserve the ability to push, and maintain maternal satisfaction

Avoid maternal hypotension

Minimize placental transfer of drugs to the fetus

Reduce the risks of LA systemic toxicity (LAST) for unrecognized intravascular catheters and of high or total spinal for unrecognized intrathecal catheters (see "Adverse effects of neuraxial analgesia and anesthesia for obstetrics")

Epidural analgesia drug choice — For epidural labor analgesia, we suggest the use of a high volume of low-concentration LA epidural solution (eg, 10 to 20 mL bolus of 0.0625 to 0.1% bupivacaine, most commonly with a lipid-soluble opioid such as fentanyl 2 mcg/mL). The use of high-volume, low-concentration solutions results in superior analgesia and a lower total dose of LA compared with higher-concentration, lower-volume regimens, based on small randomized studies [56-58]. This principle applies to both bolus administration and infusion of LA solutions. As an example, one study evaluated the effect of a fourfold difference in concentration and volume of LA for epidural analgesia for labor [56]. Patients were randomized to receive epidural analgesia with a 5-mL bolus of 0.25% bupivacaine with 1 mcg/kg fentanyl followed by infusion of plain bupivacaine 0.25% at 5 mL/hour, or a 20 mL bolus of 0.0625% bupivacaine with fentanyl 1 mcg/kg followed by infusion of plain bupivacaine 0.0625% at 20 mL/hour (equivalent mg dose/hour). Patient satisfaction was greater, and the median subsequent PCEA bupivacaine dose was lower with the bupivacaine 0.0625% solution.

More concentrated epidural LA solutions may be administered for labor analgesia top-ups, particularly to provide a sacral block during the second stage of labor, and for assisted vaginal delivery.

Epidural local anesthetics

Bupivacaine and ropivacaine – The LAs most commonly used for epidural labor analgesia in the United States are bupivacaine and ropivacaine, which are homologous, long-acting amide LAs. Bupivacaine 0.0625 to 0.1% or ropivacaine 0.08 to 0.1% is usually administered in combination with fentanyl or sufentanil. The authors use different concentrations of LA (ie, bupivacaine 0.0625% and bupivacaine 0.1%, respectively) in combination with fentanyl 2 mcg/mL for our epidural solutions.

-Potency – The analgesic potency of ropivacaine is approximately 60 percent that of bupivacaine [59]. At equipotent doses and at the dilute concentrations currently used for labor analgesia, the two LAs appear to produce clinically comparable motor blocks [60].

-Cardiotoxicity – Animal and human studies that compared cardiotoxicity of ropivacaine and bupivacaine have reported conflicting results, with some showing cardiac conduction abnormalities at lower doses of bupivacaine than ropivacaine, and others showing no difference between the two LAs. Any difference in cardiotoxicity may be of little consequence at the clinically relevant, low concentrations routinely used for labor analgesia.

-Efficacy – Maternal satisfaction, onset of analgesia, incidence of instrumental delivery, and duration of the second stage of labor are also comparable when clinically relevant, low-dose solutions of bupivacaine and ropivacaine are used [61].

LidocaineLidocaine is rarely used as the primary LA for labor analgesia because of its short duration of action and relatively high degree of motor block. Occasionally, lidocaine 1 to 2% can be used as part of a clinician top-ups, to confirm that the catheter is working properly or to provide a denser block during second-stage labor and for instrumental delivery. (See 'Clinician epidural top-ups' above.)

2-chloroprocaine – 2-chloroprocaine is an ester LA with rapid onset of action and short duration. This drug is used during labor primarily for rapid extension of labor analgesia for instrumental delivery or for urgent cesarean delivery. There is some evidence that epidural chloroprocaine reduces the efficacy of subsequently administered epidural bupivacaine and opioids [62,63], though this issue is controversial.

Epidural opioids – In contrast to intrathecal opioids, epidural opioids alone, without LA, do not provide complete analgesia, even during the first stage of labor [64]. Lipid-soluble opioids (eg, fentanyl 50 to 100 mcg or sufentanil 5 to 10 mcg) are occasionally administered in the epidural space along with an LA to initiate epidural analgesia when a combination opioid/LA solution is not immediately available, or alone as a top-up to alleviate second-stage labor pain. However, opioids are most commonly administered in the epidural space in combination with an LA.

The combination of an opioid (eg, fentanyl 1 to 3 mcg/mL or sufentanil 0.2 to 0.5 mcg/mL of LA solution) with an LA in an epidural solution allows a reduction in the dose of both drugs, improved analgesia compared with LA alone, and a more rapid onset of analgesia.

Epidural adjuvant drugs Other medications can be added to the LA solution with the goal of decreasing LA requirements and improving the quality and duration of analgesia.

EpinephrineEpinephrine is rarely used for labor epidural infusions in current practice. Epinephrine prolongs the duration of action of some LAs administered in the epidural space and may improve the analgesic quality of both opioids and LAs [65]. However, epidural epinephrine can increase the intensity of motor block. Also, systemically absorbed epinephrine can theoretically cause an undesirable relaxant effect on the uterus, as well as transient increases in maternal heart rate (HR) and blood pressure (BP), although these effects are rarely seen clinically.

In-situ epidurals may be dosed with epinephrine-containing lidocaine and sodium bicarbonate to establish surgical anesthesia for cesarean delivery.

Novel epidural adjuvants Clonidine and neostigmine are adjuvant drugs for epidural labor analgesia that appear to reduce LA requirements for labor analgesia and improve the quality and duration of analgesia, but additional research is required before they are considered for routine clinical use [66-72]. The addition of dexmedetomidine to LA epidural solutions has also been shown to provide comparable or superior labor analgesia with fewer side effects (eg, pruritus, nausea, vomiting) when compared with opioid adjuvants [73].

Intrathecal analgesia drug choice — Intrathecal injection of a lipid-soluble opioid (eg, sufentanil, fentanyl) for the combined spinal-epidural (CSE) or single-shot spinal technique provides rapid onset of labor analgesia that may be adequate in early labor. Combining opioid with LA (eg, bupivacaine, ropivacaine) for intrathecal administration increases the duration and quality of analgesia and makes it possible to reduce the amount of each individual drug [74-76]. CSE opioid dose ranges include 10 to 15 mcg fentanyl or 2.5 to 5 mcg sufentanil when combined with LA; 15 to 25 mcg fentanyl or 5 to 8 mcg sufentanil without LA. CSE LA dose ranges include 1.25 to 3.0 mg bupivacaine or, less commonly, 1.25 to 3.0 mg ropivacaine. We use a combination of fentanyl (10 to 15 mcg) with bupivacaine (2 to 2.5 mg) for optimal effect.

Intrathecal opioids Pruritus is a common side effect of intrathecal opioids. Transient fetal bradycardia may also occur with intrathecal opioid administration, particularly when higher doses are used (eg, when intrathecal opioid is used alone, without the addition of LA) [77]. (See "Adverse effects of neuraxial analgesia and anesthesia for obstetrics", section on 'Pruritus'.)

Fentanyl – Intrathecal fentanyl (15 to 25 mcg) may be used alone for CSE or single-shot techniques to provide short-acting analgesia early in labor. In practice, fentanyl is usually administered for these techniques in combination with intrathecal bupivacaine, allowing a reduced dose (10 to 15 mcg), improved quality of analgesia, and a longer duration of analgesia [2]. We use fentanyl combined with isobaric bupivacaine for the spinal portion of the CSE technique and for single-shot spinal labor analgesia.

SufentanilSufentanil is more potent than fentanyl [78], with a longer duration of action. Intrathecal sufentanil (5 to 8 mcg) may be used alone for CSE or single-shot techniques. In early labor, a reduced dose of sufentanil (eg, 2.5 mcg) may be sufficient. Like fentanyl, sufentanil is usually combined with bupivacaine or ropivacaine for intrathecal administration during CSE and single-shot spinal techniques, which allows a reduced dose (2.5 to 5 mcg), longer duration of action, and improved analgesia [75].

Given the high potency of sufentanil and the small doses routinely used in labor analgesia, the potential for drug error exists. As such, premade syringes of diluted sufentanil or sufentanil in combination with LA may be provided by the pharmacy for intrathecal administration.

Intrathecal local anesthetics Long-acting amide LAs (eg, bupivacaine, ropivacaine) are usually used for labor analgesia with a lipid-soluble opioid (eg, fentanyl, sufentanil) for effective analgesia; the combination is synergistic, allowing a lower dose of LA.

Bupivacaine – Intrathecal bupivacaine (up to 5 mg) can be used alone for labor analgesia but is more commonly combined with fentanyl (10 to 15 mcg) or sufentanil (2.5 to 5 mcg) at a reduced dose of 1.25 to 3 mg.

RopivacaineRopivacaine is less potent than bupivacaine. Intrathecal ropivacaine (1.25 to 3 mg) is usually combined with fentanyl (10 to 15 mcg) or sufentanil (2.5 to 5 mcg).

ANALGESIA FOR INSTRUMENTAL VAGINAL DELIVERY — The goal for instrumental vaginal delivery is to provide adequate analgesia while preserving the parturient's ability to push. Vacuum-assisted delivery is usually less painful than forceps delivery.

Vacuum-assisted delivery If a functioning epidural catheter is in place, maintenance epidural labor analgesia may be adequate for vacuum-assisted delivery. If needed, we administer an epidural bolus as we would for forceps delivery.

Forceps delivery – A forceps delivery is likely to be more painful than a vacuum-assisted delivery, may result in a larger perineal tear, and usually requires analgesia beyond the maintenance epidural sensory level. With an existing labor epidural in place, we administer an epidural bolus of 5 to 10 mL of 1 to 2% lidocaine with or without epinephrine or 3% 2-chloroprocaine. Bicarbonate may be added, as it may speed the onset and improve the density of the block.

In the absence of an existing epidural catheter, for instrumental delivery, we perform a single-shot spinal or combined spinal-epidural (CSE), using intrathecal local anesthetic (LA) and opioid (eg, bupivacaine 1.25 to 2.5 mg with fentanyl 10 to 15 mcg). CSE may be preferred, since the epidural can be used for anesthesia for cesarean delivery if assisted vaginal delivery fails. Higher doses of LA (eg, hyperbaric bupivacaine 6 to 8 mg or hyperbaric lidocaine 25 to 50 mg) may be required for forceps delivery. (See "Spinal anesthesia: Technique", section on 'Baricity'.)

If the assisted vaginal delivery fails, then a cesarean delivery is necessary. A functioning epidural catheter can be dosed rapidly to achieve surgical anesthesia. Anesthesia for cesarean delivery is discussed separately. (See "Anesthesia for cesarean delivery", section on 'Epidural drugs for CD'.)

PATIENTS WITH COVID-19 — UpToDate has added information on many aspects of COVID-19, including infection control, airway and other aspects of anesthetic management, intensive care, and obstetric concerns, in other topics. Important considerations specific to obstetric anesthesia include the following:

COVID-19 is not a contraindication to neuraxial anesthesia. Early epidural analgesia may reduce the need for general anesthesia and airway management should emergency cesarean delivery become necessary.

Patients with COVID-19 often receive venous thromboembolism prophylaxis. The anticoagulation regimen should be carefully considered so that the initiation of neuraxial techniques may be appropriately timed. (See "Neuraxial anesthesia/analgesia techniques in the patient receiving anticoagulant or antiplatelet medication".)

Although data are limited, an epidural blood patch to treat post dural puncture headache (PDPH) in patients with COVID-19 is likely safe. The theoretical risk of seeding the central nervous system by injecting viremic blood into the epidural space must be weighed against the risk of complications of untreated PDPH. The patient’s coagulation status must also be considered.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Post dural puncture headache" and "Society guideline links: Local and regional anesthesia" and "Society guideline links: Local anesthetic systemic toxicity" and "Society guideline links: COVID-19 – Index of guideline topics" and "Society guideline links: Obstetric anesthesia".)

PATIENT PERSPECTIVE TOPIC — Patient perspectives are provided for selected disorders to help clinicians better understand the patient experience and patient concerns. These narratives may offer insights into patient values and preferences not included in other UpToDate topics. (See "Patient perspective: Managing pain during labor and delivery".)

SUMMARY AND RECOMMENDATIONS

Indications and contraindications

Neuraxial techniques (ie, epidural, combined spinal-epidural [CSE], dural puncture epidural [DPE], single-shot spinal, and continuous spinal) may be initiated at any stage during labor to provide pain relief. Neuraxial analgesia must block T10 to L1 for the first stage of labor and extend to S2 to S4 during the late first stage and second stage of labor. (See 'Indications for neuraxial analgesia' above.)

Early neuraxial labor analgesia should be considered for both high-risk women and for laboring women who are likely to require surgical anesthesia for operative delivery to minimize the chance that general anesthesia would be required for cesarean delivery or management of peripartum hemorrhage. (See 'Preparation for surgical anesthesia' above.)

Absolute contraindications to neuraxial analgesia are rare. Some relative contraindications include coagulopathy, thrombocytopenia (algorithm 1), infection of the lower back, and increased intracranial pressure. (See 'Pain relief' above.)

Choice of neuraxial technique – Continuous epidural and CSE are the most commonly used neuraxial techniques for labor analgesia (see 'Choice of technique' above):

Spinal techniques (ie, the spinal portion of the CSE, single-shot spinal, continuous spinal, and DPE) may provide a more rapid onset of symmetric analgesia, including sacral analgesia, than a conventional epidural technique.

Catheter-based techniques (ie, continuous epidural, CSE, DPE, continuous spinal) provide analgesia with the option to convert to anesthesia for operative delivery. (See 'Epidural analgesia technique' above and 'Continuous spinal analgesia' above.)

Single-shot spinal analgesia is limited by the duration of action of the intrathecal drug injected. The single-shot technique may be indicated for patients who are in rapidly advancing labor and are expected to deliver quickly, or when epidural catheter placement is technically prohibitive. (See 'Single-shot spinal analgesia' above.)

Continuous spinal is rarely used when epidural catheter placement is not feasible and a titratable technique is needed. Continuous spinal is also a reasonable option after an accidental dural puncture during attempted epidural placement. (See 'Continuous spinal analgesia' above.)

Drug combinations – The drugs used for neuraxial labor analgesia techniques usually include a combination of dilute local anesthetic (LA) and an opioid. The goal should be to use the lowest effective total dose of drugs to minimize motor block, avoid hypotension, minimize placental drug transfer, and reduce the chance of LA toxicity. The combination of LA with opioid allows the use of lower doses of each class of drug (table 2). (See 'Drug choice for neuraxial analgesia' above.)

CSE technique

CSE analgesia is usually performed with a needle-through-needle technique, followed by insertion of an epidural catheter. CSE is initiated with subarachnoid injection of LA and/or opioid. (See 'CSE technique' above.)

For CSE or single-shot spinal analgesia, the combination of an opioid (eg, fentanyl or sufentanil) with LA (eg, bupivacaine, ropivacaine) for intrathecal administration increases the duration and quality of analgesia and makes it possible to reduce the amount of each individual drug. We use a combination of fentanyl (10 to 15 mcg) with bupivacaine (2 to 2.5 mg) (table 2). It is helpful to ask the patient to administer a bolus (or to have the pump administer a bolus) within 30 minutes to an hour after the spinal medication has been administered, even in the absence of pain, to provide a smooth transition to the epidural block. (See 'Intrathecal analgesia drug choice' above.)

Epidural technique

Continuous epidural analgesia is initiated with a bolus of a solution that usually includes a combination of LA with opioid, with or without an epidural test dose.

For epidural labor analgesia, we suggest the use of a high volume of low-concentration LA epidural solution, rather than a lower volume of high-concentration solution (Grade 2B). We generally administer a 15 to 20 mL bolus in 5 mL increments, with aspiration between boluses, of 0.0625 to 0.1% bupivacaine with fentanyl 2 mcg/mL or ropivacaine 0.08 to 0.1% with fentanyl 2 mcg/mL, with or without an epidural test dose (eg, 3 mL lidocaine 1.5% with epinephrine), to initiate epidural analgesia. There are many acceptable alternative regimens (table 2). (See 'Initiation of epidural analgesia' above and 'Epidural analgesia drug choice' above and 'The epidural test dose in obstetrics' above.)

More concentrated LAs may be used for top-ups or for instrumental vaginal delivery. (See 'Clinician epidural top-ups' above.)

Epidural test dose – If a traditional test dose (ie, 3 mL of lidocaine with epinephrine) is used to evaluate appropriateness of epidural catheter placement, it should not be administered during a contraction. To evaluate for intrathecal injection, wait at least three to five minutes to confirm that the patient is not developing a motor block. (See 'The epidural test dose in obstetrics' above.)

Epidural maintenance – Epidural analgesia is maintained with a dilute LA with opioid solution (eg, bupivacaine 0.0625 to 0.1% with fentanyl 2 mcg/mL, or ropivacaine 0.08 to 0.1% with fentanyl 2 mcg/mL), which is administered via an infusion pump, programmed for continuous infusion, patient-controlled epidural analgesia (PCEA), or programmed intermittent epidural bolus (PIEB), or a combination of these modalities (table 2). (See 'Modes of drug administration' above.)

Breakthrough pain – Breakthrough pain during neuraxial labor analgesia may be the result of anesthetic and/or obstetric issues. We replace unilateral, patchy, or otherwise nonfunctioning epidurals in parturients who remain uncomfortable after one or two unscheduled clinician top-ups unless there is a plausible explanation for their breakthrough pain (eg, a period of rapid cervical dilation). Replacing the catheter usually results in improved comfort. (See 'Clinician epidural top-ups' above.)

Instrumental delivery – Instrumental delivery, particularly forceps delivery, often requires more dense analgesia than spontaneous delivery. The goal is to provide adequate analgesia while preserving the ability to push. With an existing labor epidural analgesic, we administer 5 to 10 mL of 1 to 2% lidocaine, with or without epinephrine, or 3% 2-chloroprocaine through the catheter. In the absence of an in-situ labor epidural, options include a CSE, a single-shot spinal, or a pudendal block. (See 'Analgesia for instrumental vaginal delivery' above.)

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