Continuous epidural analgesia for postoperative pain: Benefits, adverse effects, and outcomes

INTRODUCTION — Continuous epidural analgesia may be used for postoperative pain control after thoracic, abdominal, or lower extremity surgery. Whereas continuous epidural was once considered the standard method of postoperative analgesia for many procedures, other equally effective, potentially safer, and more cost-effective options have emerged. This topic will discuss the potential benefits and adverse effects of continuous epidural analgesia, and outcomes when used for some specific surgical procedures.

Epidural placement technique and management of continuous epidural analgesia are discussed separately. (See "Epidural and combined spinal-epidural anesthesia: Techniques" and "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Choosing catheter insertion site'.)

INDICATIONS — Continuous epidural analgesia is primarily used for open thoracic and open abdominal surgery, though it may be used for genitourinary or lower extremity surgery as well. Epidural catheters are typically used for patients who will be hospitalized for more than 24 hours after surgery and is rarely used for minimally invasive surgery.

Over time the indications for and the use of continuous epidural analgesia have decreased with reduced length of hospital stay for many procedures, increased emphasis on minimally invasive surgery, and the evolution of perioperative pain control strategies. Multimodal opioid sparing analgesic strategies with nonopioid analgesics, peripheral nerve blocks, local anesthetic infiltration and other techniques may provide analgesia equivalent to epidural analgesia for many procedures, without the risks, adverse effects, and cost of epidurals. Epidural analgesia is included in some enhanced recovery after surgery protocols, in some cases as an alternative along with other regional anesthesia options. (See "Anesthetic management for enhanced recovery after thoracic surgery", section on 'Regional anesthetic techniques'.)

Epidural analgesia may be indicated for patients in whom other more peripheral regional anesthesia techniques (eg, paravertebral or fascial plane blocks, local anesthetic infiltration) are not appropriate. Importantly, epidural analgesia may also be indicated for patients whose pain is likely to be difficult to control (eg, patients with chronic opioid use, high levels of pain related anxiety, or a history of difficulty with pain control).

For most indications for perioperative analgesia, thoracic epidural analgesia is used rather than lumbar epidural analgesia, as lumbar block increases the risk of urinary retention and lower extremity weakness. (See 'Side effects' below and "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Thoracic versus lumbar catheter placement'.)

CONTRAINDICATIONS — There are a few absolute contraindications to neuraxial analgesia/anesthesia procedures. They include patient refusal, severe systemic infection, local infection at the needle insertion site, epidural abscess or central nervous system infections, and inability to position the patient for epidural placement.

The decision to perform neuraxial anesthesia/analgesia procedures must always involve a risk-benefit analysis. Epidural anesthesia/analgesia procedures should be carefully considered and may be relatively contraindicated in patients with coagulopathy or taking anticoagulant or antiplatelet medications, spinal stenosis, spine abnormalities at the needle placement site, or intracranial mass lesions with increased intracranial pressure. These issues are discussed separately. (See "Overview of neuraxial anesthesia", section on 'Preoperative evaluation'.)

POTENTIAL BENEFITS OF EPIDURAL ANALGESIA — A number of the benefits historically thought to be associated with epidural analgesia are less clear in the context of multimodal opioid sparing analgesia and the use of other alternative regional anesthesia techniques. The decision to use continuous epidural analgesia must balance the benefits that are discussed in this section with the side effects and adverse effects that are discussed below. (See 'Side effects' below.)

Analgesia — Postoperative epidural analgesia can provide excellent pain control, as well as reduced systemic opioid requirement, and reduced opioid related side effects [1-6]. Whether epidural analgesia is more effective than other analgesic techniques is less clear, particularly in the current era of multimodal postoperative analgesia. Multimodal postoperative analgesia includes nonpharmacologic strategies, nonopioid analgesics, regional anesthesia techniques (eg, neuraxial analgesia, peripheral nerve blocks, local anesthetic infiltration), and opioids as necessary. Such strategies are discussed in detail separately. (See "Approach to the management of acute pain in adults".)

Analgesic efficacy found in randomized trials may not reflect the benefit in clinical practice because of the significant rate of failure or dislodgement of epidural catheters, as discussed below. (See 'Inadequate or failed analgesia' below.)

In multiple studies, patient satisfaction with epidural analgesia appears to be high, and higher than with intravenous (IV) patient controlled analgesia (PCA) [4,5,7,8]. However, conclusions are limited by lack of a standardized method for assessing patient satisfaction with analgesic regimens.

●Epidural analgesia versus patient controlled analgesia – The literature comparing postoperative epidural analgesia versus IV PCA is conflicting, with some studies finding modestly improved pain control with epidural analgesia [9], and others suggesting similar analgesia with the two techniques [10,11].

In one multicenter trial (the PAKMAN trial) of 248 patients who underwent pancreaticoduodenectomy and were randomly assigned to postoperative IV PCA versus perioperative thoracic epidural analgesia, postoperative pain scores at rest and with movement were low (<3.5/10) and similar in the two groups [10]. There were structured pain management programs and the support of acute pain services in the participating centers.

●Epidural analgesia versus peripheral nerve blocks (including paravertebral blocks) – For many surgical procedures, peripheral nerve blocks may provide analgesia equivalent to epidurals, often with a lower incidence of side effects with nerve blocks. (See 'Side effects' below.)

Examples of relevant studies are as follows:

•Transversus abdominus plane (TAP) blocks – A meta-analysis of randomized trials comparing TAP blocks with epidural analgesia for abdominal surgery found statistically significant but clinically unimportant reductions in pain scores and postoperative opioid consumption with epidural analgesia [12]. The quality of evidence was low or very low.

Similarly, in a trial comparing epidural analgesia versus continuous TAP and rectus sheath blocks after hepatic resection, median postoperative pain scores were low (<3/10) in both groups, and were lower with epidural analgesia up until postoperative day 2 [13].

•Thoracic paravertebral block – In a meta-analysis of randomized trials that compared thoracic epidural analgesia versus thoracic paravertebral block (TPVB) for analgesia after thoracotomy (14 trials, 698 patients), postoperative pain scores at rest and with cough were similar in the two groups [14]. The quality of evidence was moderate. (See "Anesthesia for open pulmonary resection", section on 'Choice of technique'.)

In a randomized trial that compared TPVB versus epidural analgesia after hepatic resection, mean postoperative pain scores were slightly lower with epidural analgesia up to 48 hours (mean difference 0.89/10) [15]. Postoperative opioid consumption was similar in the two groups.

The role of epidural analgesia in preventing persistent postsurgical pain is unclear, without high quality evidence of benefit. This is discussed in detail separately. (See "Chronic postsurgical pain: Incidence, risk factors, and potential risk reduction", section on 'Regional anesthesia techniques for analgesia'.)

Improved pulmonary function — Postoperative epidural analgesia can improve respiratory function and may reduce the risk of respiratory complications. However, such benefits are also true of peripheral nerve blocks, as discussed above. (See 'Analgesia' above.)

Adequate pain control can improve the patient’s ability to take deep breaths, facilitate coughing, and avoid atelectasis, particularly after abdominal or thoracic surgery. Effective epidural analgesia may also reduce the risk of respiratory depression by decreasing systemic opioid requirements. (See "Strategies to reduce postoperative pulmonary complications in adults", section on 'Pain control' and "Anesthesia for open pulmonary resection", section on 'Regional anesthesia'.)

Historically, improved respiratory function has been one of the most consistently reported positive impacts of epidural analgesia [2,3,16-18]. In a 2014 meta-analysis of randomized trials that compared postoperative epidural analgesia with systemic opioid analgesia for various surgical procedures, epidurals reduced the incidence of pneumonia, respiratory depression, and atelectasis, with similar rates of reintubation and prolonged ventilation [16]. A subsequent randomized trial of patients who had major abdominal cancer surgery found that postoperative patient controlled epidural analgesia reduced the rate of pneumonia, compared with patient controlled intravenous analgesia [1].

In contrast, the PAKMAN trial described below found similar rates of postoperative pneumonia in patients who had thoracic epidural analgesia versus patient controlled intravenous analgesia after pancreaticoduodenectomy [10].

Faster return of bowel function/gastrointestinal outcomes — Whether epidural analgesia reduces postoperative ileus and postoperative gastrointestinal complications is unclear. Possible mechanisms for such benefits include reduced opioid administration, parasympathetic predominance as a result of the epidural induced sympathectomy, or an effect of systemic absorption of local anesthetic [17,19]. There may be less incremental benefit of epidural analgesia with increasing use of multimodal opioid sparing analgesia and some peripheral nerve blocks that may cause sympathetic block as well (eg, thoracic paravertebral block).

Literature on the effects of epidural analgesia on gastrointestinal outcomes is conflicting.

●A number of studies have found that epidural analgesia improves recovery of gastrointestinal motility, particularly when thoracic epidural analgesia is used [3,16,17,20,21].

●In contrast, in an international trial (PAKMAN) of 248 patients who underwent pancreaticoduodenectomy and were randomly assigned to thoracic epidural analgesia versus intravenous patient controlled analgesia (PCA), gastrointestinal complications were similar in the two groups [10].

●Two retrospective studies found an association between the use of epidural analgesia and increased gastrointestinal complications (eg, delayed return of bowel function, fistulae), though conclusions are limited by potential confounding [22,23].

Reduced thrombosis — Whether continuous epidural analgesia reduces the incidence of deep vein thrombosis (DVT) or pulmonary embolism in contemporary practice is unclear. Older studies suggested a possible benefit of epidurals [24,25]. In contrast, other studies of surgical patients and those with major trauma are mixed, with some showing similar or increased risk of venous thromboembolism in patients who had epidural catheters placed [26-29]. Possible mechanisms for reduced thromboembolism include improved lower extremity blood flow due to sympathectomy associated with epidurals placed at T10 to L2, better pain control and improved postoperative mobilization, altered coagulation, and reduced inflammation and/or stress response. (See "Overview of neuraxial anesthesia", section on 'Physiologic effects of neuraxial anesthesia'.)

This issue may be less relevant with contemporary use of mechanical and pharmacologic antithrombotic therapy and the emphasis on early postoperative mobilization.

Reduced cardiac morbidity and mortality — The impact of epidural analgesia on cardiovascular (CV) outcomes is unclear. In the current era of enhanced recovery after surgery (ERAS) protocols and multimodal analgesia, it is becoming increasingly challenging to isolate the impact of the epidural analgesia on cardiac morbidity or mortality. The sympathectomy associated with epidural analgesia may be cardioprotective, but it may also cause hypotension and reduced myocardial perfusion (see 'Hypotension' below).

In addition, beneficial effects could be the result of optimal analgesia, which can be achieved with strategies that do not involve epidurals. (See 'Analgesia' above.)

The literature on the effects of epidural analgesia on cardiovascular adverse events is inconsistent. Whereas some studies have found that epidural analgesia reduces adverse cardiovascular events compared with systemic opioids [1], others have found no difference in cardiovascular complications in most patients [10,22,30], or even an increase in complications [31-33].

It is unlikely that epidural analgesia reduces mortality after major surgery.

●A 2002 multicenter randomized trial (MASTER) compared major adverse outcomes in over 900 high risk patients who had major surgery and were randomly assigned to receive general anesthesia and postoperative systemic opioid analgesia, versus combined general and epidural anesthesia followed by postoperative epidural analgesia [2]. Major morbidity and mortality were similar in the two groups.

●In a 2014 meta-analysis of 10 randomized trials (2200 patients) that compared postoperative epidural analgesia versus systemic opioids in adults who had general anesthesia for surgery, mortality within 30 days was lower in patients who had epidural analgesia (3.1 versus 4.9 percent, odds ratio [OR] 0.60, 95% CI 0.39–0.93) [16]. When three outlier studies were excluded from the analysis, the mortality rate was still lower in the epidural group, but the 95% CI for the odds ratio crossed 1 (1.8 versus 2.4 percent, 95% CI 0.42–1.02).

●A subsequent randomized trial of patients who underwent open pancreatectomy [10], and several large database studies [22,31,34] also found similar rates of mortality in patients who had postoperative epidural analgesia versus those who did not.

Reduced stress response to surgery — Epidural analgesia may reduce the postoperative stress response [35], particularly when used along with other elements of ERAS protocols. One of the goals of ERAS protocols is to reduce the perioperative stress response. However, many ERAS protocols do not prefer epidural analgesia, and other forms of analgesia (eg, thoracic paravertebral block) may reduce the stress response as well as or better than epidural analgesia [36]. (See "Enhanced recovery after colorectal surgery".)

The surgical stress response is a complex neuroendocrine/metabolic and inflammatory/immune process that can result in perioperative complications. A full discussion of the stress response is beyond the scope of this topic. Briefly, neuraxial analgesia primarily blocks the hypothalamic-pituitary-adrenal axis response to surgery, partly by providing effective pain control, thereby reducing plasma corticotropin (ACTH), cortisol, adrenaline, and growth hormone secretions [37]. Observational studies have found reduced levels of urinary cortisol, plasma catecholamines, and postoperative protein catabolism in patients who had epidural analgesia [24,35,38,39].

Reduced length of stay — Epidural analgesia alone likely has little impact on length of stay. Determinants of length of stay after surgery are multifactorial and evolving with changes in perioperative care. Whereas optimal analgesia may improve mobility and enhance recovery, associated hypotension or motor block could have the opposite effect.

In a randomized trial of patients who underwent pancreaticoduodenectomy, length of stay was similar in patients who had postoperative epidural analgesia versus IV PCA [10]. Similarly, a meta-analysis of 16 trials including patients who underwent colorectal surgery found no difference in length of stay with the use of epidural analgesia versus IV PCA [40]. Retrospective database studies have found conflicting results, with some showing reduced length of stay associated with epidural analgesia for open surgery [34], and others finding longer length of stay [22,31,41].

SIDE EFFECTS

Hypotension — Hypotension is a common side effect of epidural analgesia due to the associated sympathectomy and is more common with thoracic epidural analgesia (up to 14 percent of patients). Risk factors for hypotension include patient factors (eg, comorbidities, type of surgery, intravascular fluid volume) and the degree of sympathetic blockade. These issues are discussed in detail separately. (See "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Hypotension'.)

Motor block — Motor block is a relatively common side effect of epidural analgesia, occurring more frequently with lumbar than with thoracic catheter placement [42]. Motor block limits postoperative mobilization and participation in physical therapy and can increase the risk of falls.

The reported rate of motor block associated with thoracic epidural analgesia is from 0.6 to approximately 10 percent [8,42], and up to 30 percent after lumbar catheter placement [42]. As an example, in a single center review of approximately 19,000 cases in which epidural analgesia was used after abdominal cancer surgery, lower extremity weakness or numbness occurred in 30 percent of patients who had lumbar epidural catheters placed, versus 10 percent of those who had thoracic catheters [42]. Most resolved after discontinuation of the epidural; 6 patients (0.03 percent) had persistent deficits of uncertain etiology. In another single institution study of over 4700 cases of postoperative epidural analgesia, motor block occurred in 0.6 percent of patients who had thoracic catheters, and 4 percent of those who had lumbar catheters [8]. In one percent of patients the epidural was discontinued because of motor block.

Management of motor block during epidural analgesia is discussed separately. (See "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Motor block'.)

Urinary retention — Epidural analgesia may inhibit bladder sensation and function, and can cause postoperative urinary retention. Urinary retention may require bladder catheterization, which can limit postoperative mobilization and cause urinary tract infection. Postoperative urinary retention is a common, multifactorial problem, and the role of epidural analgesia is often unclear. Urinary retention is less common after thoracic epidural placement, compared with lumbar placement, as the afferent and spinal segments that innervate the bladder and internal urethral sphincter are primarily from lumbar and sacral nerve roots [43].

The choice of epidural analgesic solutions as it relates to side effects, including urinary retention, is discussed separately. (See "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Choice of epidural drugs for postoperative analgesia'.)

Pruritus — Pruritus is a side effect of neuraxial opioids, though it can occur with systemic opioids as well. It is rarely severe enough that the patient asks to discontinue the epidural or change the infusion [7,8]. If necessary, pruritus can be treated with low dose naloxone or nalbuphine. This is discussed separately. (See "Adverse effects of neuraxial analgesia and anesthesia for obstetrics", section on 'Pruritus'.)

Pruritus may be more common with epidural analgesia than with systemic opioids. In one meta-analysis of randomized trials, pruritus occurred in 17.3 percent of patients who had an epidural, compared with 12.5 percent of patients with IV PCA [16]. Another large review also found modestly increased pruritus with epidural analgesia (16.1 versus 13.8 percent) [44].

Nausea — Nausea may be a side effect of epidural opioids, and can also result from hypotension. In the absence of hypotension, in most cases epidural analgesia reduces the need for systemic opioids, and therefore reduces the incidence of postoperative nausea. A lower incidence of nausea with epidural analgesia compared with systemic opioids has been found in a number of studies [16,44,45]. In a single institution prospective study of patients who had low thoracic postoperative epidural analgesia, nausea declined from 12.8 percent of patients in the PACU to 4.6 percent on postoperative day 3, and in 0.4 percent of patients the epidural was removed due to nausea [8].

Sedation/respiratory depression — Respiratory depression and sedation may occur as a result of systemic absorption of epidural opioids. However, the incidence of respiratory depression in patients who receive neuraxial opioids is low, and lower or similar to systemic opioids. A meta-analysis of six trials that compared neuraxial versus systemic opioids for postoperative pain found a lower rate of respiratory depression in patients who received neuraxial versus systemic opioids (odds ratio 0.32, 95% CI 0.12–0.86) [46]. All patients who have continuous epidural administration of opioids should be monitored for respiratory depression. The American Society of Anesthesiologists has published guidelines for respiratory monitoring in these patients [46]. Monitoring for respiratory depression and management when sedation or respiratory depression occur are discussed separately. (See "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Monitoring during epidural analgesia'.)

COMPLICATIONS — Complications common to all epidural anesthesia procedures (ie, post dural puncture headache, nerve or spinal cord injury, local anesthetic systemic toxicity) are discussed separately. Those that are related to continuous epidural analgesia are discussed here. (See "Post dural puncture headache" and "Overview of neuraxial anesthesia".)

Inadequate or failed analgesia — The reported incidence of failure of epidurals to provide satisfactory analgesia is between 6 and 41 percent, depending on the definition of failure. Inadequate analgesia may be the result of patient factors, surgical issues, or technical factors (eg, catheter dislodgement, inadequate drug dose or pump failure, or an epidural site incongruent with the required dermatome). These issues and management of inadequate analgesia are discussed in detail separately. (See "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Inadequate analgesia'.)

Infection — Serious infection related to placement of an epidural catheter is extremely rare, and the incidence is difficult to determine. The reported rates of deep spinal infection associated with continuous epidural in non-obstetric patients is from 1:1368 to 1:13,888 [8,42,47]. Superficial infection or inflammation at the insertion site is more common. The incidence of both superficial and deep infection likely increases with the duration of epidural catheter use.

●In a database study of approximately 19,000 patients who had epidural analgesia for a mean of 3 days after oncologic surgery, insertion site tenderness, blistering, and erythema occurred in 4.4, 3.0, and 2.0 percent, respectively, and purulent exudate in 0.1 percent [42].

●In a retrospective multi-institution German study of over 20,400 patients who had continuous postoperative epidural analgesia for up to 15 days, the risk of infection increased at 4 days, and increase further with each day of continued catheter use thereafter [48]. There was a 1 percent risk of infection on day 4 of use, 5 percent on day 7 of use, and 27 percent risk at day 15. Infection was broadly defined and included signs and symptoms ranging from erythema, edema and localized pain at the site of insertion to a severe infection requiring surgical intervention. The overall incidence of mild infection, moderate, and severe infection was 3.3, 0.6, and 0.07 percent, respectively [48].

Risk factors for infection with epidural analgesia include older age, chronic kidney dysfunction, and cirrhosis. Spinal epidural abscess is discussed in detail separately [42]. (See "Spinal epidural abscess", section on 'Epidemiology'.)

Spinal epidural hematoma — Spinal epidural hematoma is an extremely rare complication of epidural anesthesia techniques in patients with normal coagulation. The reported incidence of SEH based on retrospective data is from 1:18,000 to 1:7200 neuraxial anesthetics. (See "Neuraxial anesthesia/analgesia techniques in the patient receiving anticoagulant or antiplatelet medication", section on 'Incidence and risk factors for SEH after neuraxial anesthesia'.)

The risk is increased in patients with coagulopathy, including those who are receiving anticoagulant or antiplatelet medication. Spinal epidural hematoma can be devastating, with potential for neurologic injury or paralysis. Thus, the American Society of Regional Anesthesia and Pain Medicine (ASRA) and European anesthesia societies have published guidelines for regional anesthesia in patients receiving antithrombotic or thrombolytic therapy, shown in tables (table 1 and table 2). Importantly, there is a risk of bleeding when the epidural catheter is removed, and the guidelines make recommendations for timing related to anticoagulant dosing for both performing the block and for removing an epidural catheter. These issues are discussed in detail separately. (See "Neuraxial anesthesia/analgesia techniques in the patient receiving anticoagulant or antiplatelet medication".)

USE AND OUTCOMES FOR VARIOUS TYPES OF SURGERY

Thoracic surgery

●Thoracotomy – Thoracic epidural analgesia (TEA) provides effective pain control after open thoracotomy, which can result in severe pain. TEA has been included as an option in enhanced recovery after thoracic surgery protocols. However, continuous paravertebral block may provide similar analgesia, with a lower incidence of hypotension and urinary retention. These issues are discussed in detail separately. (See "Anesthesia for open pulmonary resection", section on 'Regional anesthesia'.)

●Video assisted thoracoscopic surgery (VATS) – The optimal method of pain relief after video-assisted thoracoscopic surgery is unclear, and practice varies. Postoperative pain after VATS is usually less than after open thoracotomy, though there can be significant incisional and ipsilateral shoulder pain. The choice of analgesic strategy, including the role of thoracic epidural analgesia, is discussed separately. (See "Anesthesia for video-assisted thoracoscopic surgery (VATS) for pulmonary resection", section on 'Postoperative pain management'.)

Abdominal surgery — Most of the data regarding the benefits of epidural analgesia come from studies of its use for abdominal surgery. As described above, much of the purported benefit of the routine use of continuous epidural analgesia after major abdominal surgery has been questioned or disproven in contemporary practice. Several trials have found no mortality benefit and a limited reduction in morbidity from epidural analgesia. (See 'Potential benefits of epidural analgesia' above.)

Epidural analgesia may be most appropriate for patients who undergo major abdominal surgery and those who will be hospitalized for at least several days (eg, radical cystectomy, open nephrectomy, liver resection, major gynecologic surgery). For less painful surgery, patient factors should be considered (eg, chronic pain, opioid use disorder, opioid sensitivity); the analgesic benefits may outweigh the risks for patients whose pain is difficult or less safe to control with other methods. For patients who undergo minimally invasive surgery, epidural analgesia has limited application, since patients are often discharged the same or next day, and pain is less severe than after open surgery.

For a number of specific types of abdominal surgery, the literature comparing outcomes with epidural analgesia versus other options is conflicting, particularly with current use of multimodal analgesia and alternative regional anesthesia techniques (eg, fascial plane blocks) [49,50]. In some protocols for enhanced recovery after surgery, epidural analgesia is one option, but it is rarely recommended more highly than other proposed methods.

The use of epidural analgesia for hepatic resection is controversial due to postoperative liver dysfunction and coagulopathy, and practice varies. Practices which utilize epidurals for postoperative analgesia in these procedures frequently monitor for evolving coagulopathies. This is discussed separately (see "Anesthesia for the patient with liver disease", section on 'Coagulopathy and epidural analgesia').

In one retrospective study of 50 patients who underwent open hepatic resection, the use of a thoracic epidural analgesia was compared to the use of a continuous erector spinae block [51]. Opioid consumption for 24 and 48 hours postoperatively was significantly lower in the epidural group and pain scores remained significantly lower in the epidural group through postoperative day 5.

Urology — Epidural analgesia is often included as an option in enhanced recovery after surgery (ERAS) protocols for major urologic surgery, and may be appropriate for these often very painful procedures. However, evidence regarding outcomes for some procedures is conflicting.

●Radical cystectomy – Some studies have reported benefits of postoperative epidural analgesia after radical cystectomy, including reduced time to first bowel movement [52], earlier oral intake, and earlier ambulation [53]. In contrast, a study of patient data in the National Surgical Quality Improvement Program (NSQIP) database for the years of 2014 to 2016 found that thoracic epidural use for radical cystectomy was associated with an increased length of stay, an increased rate of transfusion, and an increased rate of major and minor complications [54]. Similarly, in a study of a Medicare database for approximately 8000 patients who underwent radical cystectomy for cancer, epidural analgesia was associated with increased length of hospital stay, increased rate of discharge to a facility other than home, and increased 30 day readmission, compared with patients who did not have epidural analgesia [31]. Epidural analgesia was also associated with a slight increase in postoperative myocardial infarction within 30 days (2.6 versus 1.3 percent), without a difference in 30 day mortality. Conclusions from these studies are limited by their retrospective nature and potential confounding.

Radical cystectomy ERAS bundles that include epidural analgesia have been associated with decreased pneumonia, bowel obstruction, myocardial infarction (MI), deep vein thrombosis (DVT), and blood transfusion, as well as earlier ambulation and improved quality-of-life score [53,55]. However, the contribution of epidural analgesia to these benefits has not been determined.

●Open nephrectomy – Epidural analgesia has been found to provide superior analgesia to intravenous opioids after open nephrectomy. Limited evidence comparing epidural with other regional anesthesia techniques is mixed.

•One single institution trial randomly assigned 60 patients having open nephrectomy to epidural analgesia, continuous surgical site analgesia, or patient controlled intravenous analgesia (PCA) [45]. Continuous surgical site analgesia (CSSA) consisted of two catheters placed by the surgeon, one in the transversus abdominis plane, and another placed subcutaneously. Pain scores and opioid consumption were lower in both regional anesthesia groups. Pain at rest was lower in the epidural group than the CSSA group for the first 6 hours and was lower with cough for the first 72 hours. At one month after surgery, residual pain was lower in both regional anesthesia groups, and lowest in the CSSA group. There was less nausea and vomiting and a quicker return of bowel function in both regional anesthesia groups, compared with PCA.

•In a small randomized trial that compared epidural analgesia with quadratus lumborum block in 55 patients who underwent open nephrectomy, epidural analgesia reduced opioid consumption in the first 72 hours (median 70 mg versus 30 mg morphine equivalents), without a clinically relevant difference in pain scores [56]. Of note, this study was stopped early when futility boundaries were crossed when the second interim analysis was performed.

Gynecologic surgery — Continuous epidural use has limited application for minimally invasive gynecologic surgery, no matter the benefits, because patients are often discharged the same day or the next morning. In contrast, patients having open abdominal gynecologic surgery may benefit from a continuous thoracic epidural [57-59]. Results of studies of the use of epidurals in these patients are mixed.

●In a single institution randomized trial of 100 patients who underwent open gynecologic surgery for cancer, epidural analgesia resulted in less pain with movement and less sedation than PCA, whereas there was more motor block with epidurals. Pain scores at rest, nausea and vomiting, and ileus were similar in the two groups [58].

●In a single institution retrospective study of 561 patients who underwent laparotomy for gynecologic cancer, 305 of whom had epidural analgesia, epidural analgesia was associated with decreased postoperative pain and opioid, decreased length of stay, and reduced incidence of wound complications [59]. Epidurals were associated with more postoperative hypotension.

●Two studies have found increased length of stay in patients who had epidural analgesia after open gynecologic surgery [22,41]. However, both used observational data, and confounding is possible.

Open aortic surgery — Thoracic epidural analgesia may provide improved analgesia and may reduce morbidity and length of ICU stay for patients who undergo open aortic surgery. Complications of epidurals may be increased in these patients due to comorbidities and the need for anticoagulation. These issues and relevant evidence are discussed in detail separately. (See "Anesthesia for open abdominal aortic surgery", section on 'Postoperative pain management'.)

Orthopedic surgery — In contemporary practice, continuous epidural analgesia is not routinely used for patients who undergo elective lower extremity orthopedic surgery (eg, arthroplasty), because of the increasing use of other regional anesthesia techniques and the emphasis on early physical therapy and reduced length of stay. Epidural analgesia may be beneficial for patients who are having complex procedures, or who will have pain that is difficult to control (eg, patients chronically using opioids or those with high levels of pain). (See "Anesthesia for total knee arthroplasty", section on 'Epidural analgesia'.)

Epidural analgesia may also be appropriate for patients with severe trauma (eg, pelvic fracture, femur fracture), who will require analgesia for several days, or patients with severe lower extremity trauma. (See "Anesthesia for orthopedic trauma".)

Lower extremity amputation — Pain following lower extremity amputation is complex and multifactorial, often including residual limb pain, chronic ischemic pain and phantom limb sensations and pain in addition to acute postoperative pain. Neuraxial analgesia has been widely used as part of the multimodal analgesia after amputation. However, the role of epidural analgesia in the prevention of phantom limb pain is not well-defined. The existing literature is limited. In two randomized trials, epidural analgesia after lower limb amputation did not reduce the incidence of phantom limb pain at six months or a year, compared to systemic opioid analgesia [60,61]. (See "Lower extremity amputation", section on 'Phantom limb pain' and "Chronic postsurgical pain: Incidence, risk factors, and potential risk reduction", section on 'Regional anesthesia techniques for analgesia'.)

Use of neuraxial analgesia must be carefully considered in patients who need antithrombotic therapy; many patients who undergo amputation have vascular disease and related comorbidities [62]. (See 'Spinal epidural hematoma' above.)

Continuous peripheral nerve block may be the preferred method of analgesia for many patients who undergo amputation, particularly for below the knee amputation. Peripheral nerve blocks avoid concerns about anticoagulation, and may allow earlier mobilization and rehabilitation, compared with epidural analgesia. However, epidural analgesia provides complete coverage even for above the knee amputation, avoiding the need for multiple nerve blocks. (See "Chronic postsurgical pain: Incidence, risk factors, and potential risk reduction", section on 'Regional anesthesia techniques for analgesia'.)

Cardiac surgery — In the United States, epidural analgesia is not typically used after cardiac surgery, primarily due to the risk of spinal epidural hematoma in patients who receive the anticoagulation required for cardiopulmonary bypass. Neuraxial analgesia is more commonly used in other countries.

Compared with other forms of analgesia, thoracic epidural analgesia may reduce some adverse outcomes after cardiac surgery (myocardial infarction, respiratory depression, atrial fibrillation), but likely not mortality. These issues are discussed separately. (See "Postoperative care after cardiac surgery", section on 'Neuraxial and regional anesthetic techniques'.)

Spine surgery — Continuous epidural analgesia is possible after posterior spine surgery; in some institutions, surgeons place epidural catheters prior to wound closure. In one randomized trial including 26 patients who underwent major lumbar spine surgery, epidural analgesia substantially reduced pain scores and opioid consumption for the 72 hours of the study [63]. Retrospective studies have found similar results [64,65]. (See "Anesthesia for elective spine surgery in adults", section on 'Analgesia after major spine surgery'.)

Rib fractures — For inpatients with rib fractures, continuous epidural analgesia is an option for those who have inadequate pain control with other multimodal analgesic strategies. Adequate analgesia is a fundamental aspect of management of patients with rib fractures, to decrease splinting, atelectasis, and reduce the risk of pneumonia. Literature supporting the use of epidural analgesia for rib fracture is weak. A joint guideline from the Eastern Association for the Surgery of Trauma and the Trauma Anesthesiology Society made a conditional recommendation to consider epidural analgesia for patients with rib fracture, based on very low quality evidence [66]. (See "Inpatient management of traumatic rib fractures and flail chest in adults", section on 'Pain control'.)

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: Local and regional anesthesia" and "Society guideline links: Acute pain management".)

SUMMARY AND RECOMMENDATIONS

●Indications – Continuous epidural analgesia is primarily used for patients who will be hospitalized for >24 hours after thoracic and open abdominal surgery and may be used for open genitourinary or lower extremity surgery. It is rarely used after minimally invasive surgery. Epidural analgesia may be particularly beneficial for patients whose pain is likely to be difficult to control (eg, patients with chronic opioid use, pain related anxiety, or history of difficulty with pain control). (See 'Indications' above and 'Use and outcomes for various types of surgery' above.)

●Contraindications – Absolute contraindications for epidural analgesia include severe systemic infection, infection at the needle insertion site, epidural or central nervous system infection. Epidural anesthesia or analgesia should be considered carefully in patients with coagulopathy, spinal stenosis, spine abnormalities at the insertion site, or increased intracranial pressure. (See 'Contraindications' above.)

●Potential benefits – Some of the benefits that have historically been thought to result from epidural analgesia are less clear in the context of multimodal analgesia and the use of alternative regional anesthesia techniques (eg, fascial plane blocks). Compared with systemic opioid analgesia, benefits of epidural analgesia may include (see 'Potential benefits of epidural analgesia' above):

•Excellent analgesia and reduced opioid requirements

•Improved pulmonary function

•Earlier postoperative return of bowel function

•Reduced surgical stress response

Effects of epidurals on cardiac morbidity, mortality, and length of stay are unclear.

●Side effects

Common side effects of epidural analgesia include (see 'Side effects' above):

•Hypotension, more common with thoracic epidurals

•Motor block, more common with lumbar epidurals

Other side effects include urinary retention, pruritus, nausea, and rarely, respiratory depression. All patients who have continuous epidural administration of opioids should be monitored for respiratory depression. (See "Continuous epidural analgesia for postoperative pain: Technique and management", section on 'Monitoring during epidural analgesia'.)

●Complications – Complications specific to continuous epidural analgesia include the following:

•Inadequate analgesia – Failed analgesia occurs in up to 40 percent of patients, and may be due to patient, surgical, or technical factors. (See 'Inadequate or failed analgesia' above.)

•Infection – The risk of catheter related infection probably increases with the duration of catheter use. Severe, deep infection is extremely rare; infection or inflammation at the insertion site occurs in as many as 3 to 4 percent of patients. (See 'Infection' above.)

•Spinal epidural hematoma is very rare in patients with normal coagulation but may be increased in patients with coagulopathy. (See 'Spinal epidural hematoma' above and "Neuraxial anesthesia/analgesia techniques in the patient receiving anticoagulant or antiplatelet medication".)

●Use for specific types of surgery – Use of epidural analgesia for specific types of surgery is discussed above. (See 'Use and outcomes for various types of surgery' above.)