Anesthetic management for enhanced recovery after major noncardiac surgery (ERAS)

INTRODUCTION — Multimodal, multidisciplinary fast-track surgery, also known as enhanced recovery after surgery (ERAS) or enhanced recovery pathways (ERPs), can hasten functional recovery after various types of surgical procedures [1]. ERAS/ERP protocols involve evidence-based therapeutic interventions in the preoperative, intraoperative, and postoperative periods [2,3].

This topic discusses management of components (elements) of anesthetic care for enhanced recovery after major abdominal surgical procedures such as gastrointestinal surgery (eg, colorectal surgery, liver resection, gastrectomy, pancreaticoduodenal surgery). Many of the principles discussed in this topic are applicable to other types of major surgical procedures such as urologic surgery (eg, radical nephrectomy and cystectomy), orthopedic surgery (eg, total joint replacement, complex spine surgery), or breast surgery (eg, radical mastectomy).

Other topics discuss anesthetic management for enhanced recovery after cardiothoracic surgical procedures. (See "Anesthetic management for enhanced recovery after thoracic surgery" and "Anesthetic management for enhanced recovery after cardiac surgery (ERACS)".)

Details regarding surgical management of enhanced recovery after colorectal surgery or gynecologic surgery are found in separate topics. (See "Enhanced recovery after colorectal surgery" and "Enhanced recovery after gynecologic surgery: Components and implementation".)

DEFINITION OF ERAS — ERAS refers to evidence-based protocols that standardize care to minimize surgical stress response and postoperative pain, reduce complications, improve outcomes, decrease hospital length of stay, and expedite recovery following elective procedures.

The overall principles of perioperative care for major surgical procedures, particularly preoperative and intraoperative management, remain the same with a few procedure-specific variations (eg, procedure-specific pain management). (See "Enhanced recovery after colorectal surgery", section on 'Elements of ERAS' and "Enhanced recovery after gynecologic surgery: Components and implementation", section on 'Definition'.)

ERAS ELEMENTS — This table provides an overview of ERAS elements (interventions) (table 1).

Early ERAS protocols in 1990s proposed approximately 20 perioperative elements, which were selected based on the evidence obtained in other surgical settings. Subsequent studies suggested that not all ERAS elements are equally weighted for influence on postoperative complications and recovery [3]. For example, in patients undergoing colorectal surgery, intraoperative minimally invasive approaches and postoperative elements such as early oral intake and early ambulation had the greatest impact to speed recovery [4,5]. However, the overall impact of compliance with ERAS protocols was greatest for procedures performed with an open surgical approach, particularly compliance with postoperative elements [5]. Although achievement of postoperative compliance was more difficult compared with the preoperative and intraoperative phases of ERAS protocols in this study, such postoperative elements may be most important once the surgical stress response has occurred.

Several other ERAS elements including preoperative optimization of comorbid conditions, avoiding prolonged preoperative fasting, routine antiemetic prophylaxis, use of opioid-sparing analgesic techniques, maintenance of normothermia, lung-protective mechanical ventilation, antibiotic prophylaxis, and venous thromboembolism (VTE) prophylaxis have become standard of care based on extensive evidence [3]. These elements are briefly discussed below, and further detail can be found in separate topics:

●(See "Preoperative evaluation for anesthesia for noncardiac surgery".)

●(See "Preoperative fasting in adults".)

●(See "Postoperative nausea and vomiting", section on 'Prevention'.)

●(See "Antimicrobial prophylaxis for prevention of surgical site infection in adults".)

●(See "Mechanical ventilation during anesthesia in adults", section on 'Lung protective ventilation during anesthesia'.)

●(See "Perioperative temperature management".)

●(See "Approach to the management of acute pain in adults".)

●(See "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients" and "Prevention of venous thromboembolism in adults undergoing hip fracture repair or hip or knee replacement".)

Other perioperative ERAS elements such as avoidance of mechanical bowel preparation, carbohydrate loading, goal-directed fluid management, or use of epidural analgesia may be unnecessary [3].

PREOPERATIVE CONSIDERATIONS

Preanesthesia consultation — Important goals during the preanesthesia consultation are to [6]:

●Identify comorbidities and opportunities to optimize the patient's preoperative condition, which may improve postoperative outcomes. (See "Preoperative evaluation for anesthesia for noncardiac surgery", section on 'Patient risk factors' and "Preoperative evaluation for anesthesia for noncardiac surgery", section on 'Conditions that increase perioperative risk'.)

●Emphasize minimizing the fasting period and maintaining hydration during the fasting period. For example, ERAS protocols for patients undergoing colorectal surgery include advice to patients to hydrate during the fasting period, with consumption of two glasses of water prior to going to bed and two glasses of water before traveling to the hospital on the morning of surgery. There is no evidence that restriction of the volume of clear liquids is beneficial [7]. However, we do not use complex carbohydrate loading, as the evidence of benefit in the ERAS setting is weak [8]. Rather, patients are given an option to consume a simple carbohydrate drink (eg, apple juice or Gatorade) instead of two glasses of water, but the drink must be consumed at least two hours prior to surgery. (See "Preoperative fasting in adults" and "Enhanced recovery after colorectal surgery", section on 'Fasting guidelines'.)

●Educate the patient and family to set expectations regarding the patient's own role in the recovery process, and reduce patient anxiety. In particular, preoperative planning for pain management emphasizes realistic expectations regarding postoperative pain relief [6,9-11]. Such efforts lead to increased patient satisfaction [9]. (See 'Postoperative anesthetic management' below.)

Prehabilitation efforts such as nutritional supplementation, physical exercise programs, interventions to improve cognitive function, smoking cessation, and stress reduction are addressed separately. (See "Overview of prehabilitation for surgical patients".)

Medications administered in the preoperative period — Medications administered in the immediate preoperative period include:

●Oral acetaminophen 1 g, administered at least two hours preoperatively if there are no contraindications.

●Oral cyclooxygenase (COX)-2 specific inhibitor (eg, celecoxib 400 mg) at least two hours preoperatively, if no contraindications.

●For selected patients undergoing surgical procedures with a high likelihood of persistent postoperative pain, oral gabapentin 300 to 600 mg may also be administered at least two hours preoperatively [12,13]. However, we avoid gabapentin in patients who are >65 years old or have sleep-disordered breathing (eg, obstructive sleep apnea) due to concerns regarding excessive sedation, ventilatory depression, and dizziness, particularly if gabapentin is combined with opioids [14-17]. In a 2020 meta-analysis of nearly 25,000 patients participating in 281 trials, gabapentinoids were associated with reductions in pain intensity that were clinically insignificant at 6, 12, 24, and 48 postoperative hours, with no effect by 72 postoperative hours, compared with controls who did not receive gabapentinoids [17]. Postoperative nausea and vomiting (PONV) occurred less frequently in patients receiving gabapentinoids (risk ratio [RR] 0.77, 95% CI 0.72-0.82; 17,145 participants). However, a higher incidence of dizziness was noted after gabapentinoid administration (risk ratio [RR] 1.25, 95% CI 1.13-1.39; 12,054 participants) [17].

●For selected surgical procedures, thromboprophylaxis with subcutaneous heparin 5000 units, administered 30 to 60 minutes before surgery. Prophylaxis also includes placement of bilateral sequential compression devices prior to induction of anesthesia. (See "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients", section on 'Selecting thromboprophylaxis' and "Prevention of venous thromboembolism in adults undergoing hip fracture repair or hip or knee replacement".)

●We avoid routine administration of benzodiazepine premedication. Many anesthesiologists administer a small intravenous (IV) dose of a benzodiazepine, typically midazolam 1 to 2 mg, just before transfer of the patient from the holding area to the operating room. Perceived benefits include anxiolysis, sedation, amnesia, and improved patient satisfaction [18], although these benefits are controversial [19]. Potential adverse effects of benzodiazepines include postoperative amnesia, drowsiness, and cognitive dysfunction [20], increased incidence of pharyngeal dysfunction and discoordinated breathing and swallowing [21,22], and occasional unpredictable paradoxical reactions (eg, irritability, aggressiveness, delirium) [23-25]. In one large randomized trial in 1062 adults <70 years of age, premedication with a long-acting benzodiazepine (lorazepam) was associated with modestly prolonged time to tracheal extubation, delayed cognitive recovery, and no improvement in self-reported postoperative patient experiences [26].

INTRAOPERATIVE ANESTHETIC MANAGEMENT — Anesthetic agents and techniques are selected to provide optimal operating conditions with consistent and rapid recovery of cognition and physical functions such as oral intake and ambulation, ideally with minimal or no adverse effects. Other aspects of perioperative ERAS management protocols that are managed by anesthesiologists include fluid administration, temperature control, mechanical ventilation, and prophylaxis against pain and nausea/vomiting can affect both short- and long-term postoperative outcomes [2,27-29].

Induction of anesthesia — Major surgical procedures are typically performed under general anesthesia. For ERAS protocols, an intravenous (IV) anesthetic induction sequence is typically used including IV fentanyl approximately 0.5 to 1 mcg/kg ideal body weight (IBW), given three to five minutes prior to lidocaine 20 to 30 mg, followed by propofol 1 to 1.5 mg/kg to achieve loss of eyelash reflex and/or response to verbal command. In addition, a nondepolarizing neuromuscular blocking agent (NMBA) such as rocuronium 0.6 to 1 mg/kg IBW may be administered to provide muscle relaxation that facilitates laryngoscopy and insertion of an endotracheal tube (ETT). As with other intraoperative settings, it may be necessary to modify selection and dosing of anesthetic induction agents due to patient-specific factors (eg, difficult airway, aspiration risk). (See "Induction of general anesthesia: Overview".)

●Intravenous induction agents – Propofol is usually the IV induction agent of choice for ERAS protocols due to its unique recovery profile, antiemetic properties, and euphoria on emergence.

Commonly used adjuvants include lidocaine to minimize the pain associated with propofol injection and an opioid (usually fentanyl) to blunt the sympathetic responses to laryngoscopy and tracheal intubation as well as reduce the propofol dose required to achieve loss of consciousness [30,31]. (See "Induction of general anesthesia: Overview", section on 'Intravenous anesthetic induction'.)

Dosing of anesthetic induction agents and adjuvants should be judicious; large bolus doses may result in significant post-induction hypotension and need for vasopressor support [32,33]. (See "General anesthesia: Intravenous induction agents", section on 'Dosing considerations' and "Hemodynamic management during anesthesia in adults", section on 'Selection and dosing of anesthetic agents'.)

●Neuromuscular blocking agents – An intermediate-acting non-depolarizing NMBA such as rocuronium is typically selected for the induction sequence. In patients with a high risk for pulmonary aspiration or a potentially difficult airway, we select succinylcholine if there are no contraindications. Further details regarding selection of a muscle relaxant for use during induction are available in separate topics:

•(See "Induction of general anesthesia: Overview", section on 'Neuromuscular blocking agents'.)

•(See "Clinical use of neuromuscular blocking agents in anesthesia", section on 'Endotracheal intubation'.)

•(See "Clinical use of neuromuscular blocking agents in anesthesia", section on 'Adverse effects of succinylcholine'.)

Antibiotic prophylaxis — Routine IV antibiotic prophylaxis is administered 30 to 60 minutes before the surgical incision as standard of care. To achieve this timing goal, we typically administer prophylactic antibiotics immediately after induction of general anesthesia. The choice and dose of the antibiotics are discussed separately. (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults".)

Maintenance of anesthesia

Inhalation versus total intravenous anesthesia techniques — Maintenance of general anesthesia using either inhalation anesthesia or a total intravenous anesthesia (TIVA) technique is acceptable for patients participating in ERAS protocols. For either technique, it is prudent to use short-acting agents administered at the lowest possible doses since residual effects of inhalation anesthetics and IV hypnotic-sedatives, opioids, and muscle relaxants can delay recovery or result in other adverse effects. Goals for emergence from general anesthesia include planning a rapid clearheaded awakening, with adequate analgesia. (See "Maintenance of general anesthesia: Overview", section on 'Inhalation anesthetic agents and techniques' and "Maintenance of general anesthesia: Overview", section on 'Total intravenous anesthesia'.)

However, we avoid deep levels of general anesthesia. (See "Maintenance of general anesthesia: Overview", section on 'Anesthetic depth'.)

●Inhalation anesthesia – For most patients, we prefer an inhalation-based technique with a potent volatile agent (desflurane or sevoflurane) plus nitrous oxide (N₂O) 50 percent in oxygen to achieve an age-adjusted minimum alveolar concentration (MAC) value of approximately 0.8 to 1.0. (See "Inhalation anesthetic agents: Clinical effects and uses", section on 'MAC and MAC-awake values for inhalation agents'.)

Advantages of the potent volatile inhalation anesthetics include (see "Inhalation anesthetic agents: Clinical effects and uses"):

•Some degree of muscle relaxation, allowing minimized dosing of NMBA. (See "Inhalation anesthetic agents: Clinical effects and uses", section on 'Skeletal and smooth muscle relaxation'.)

•Ease of titration. (See "Inhalation anesthetic agents: Properties and delivery", section on 'Factors affecting inhalation anesthetic delivery'.)

•Availability of end-tidal anesthetic concentration (ETAC) to aid in maintenance of adequate anesthetic depth without awareness. We set alarms to detect low ETAC (eg, age-adjusted MAC <0.7). Also, we sometimes employ neuromonitoring such as processed electroencephalography (EEG) such as the bispectral index [34]. (See "Accidental awareness during general anesthesia", section on 'End-tidal anesthetic concentration' and "Accidental awareness during general anesthesia", section on 'Brain monitoring'.)

However, there is insufficient evidence to recommend use of EEG monitoring to prevent postoperative delirium or other neurocognitive disorders [34]. (See "Perioperative neurocognitive disorders in adults: Risk factors and mitigation strategies", section on 'Avoid excessive depth during general anesthesia' and "Inhalation anesthetic agents: Clinical effects and uses", section on 'Continuum of effect: sedation to general anesthesia'.)

•Rapid recovery, particularly with use of the short-acting inhalation anesthetics (sevoflurane or desflurane plus N₂O) [35]. Clinical differences between desflurane and sevoflurane appear to be small, although several studies have reported slightly more rapid emergence with desflurane [36,37]. (See "Inhalation anesthetic agents: Clinical effects and uses", section on 'Sevoflurane' and "Inhalation anesthetic agents: Clinical effects and uses", section on 'Desflurane'.)

●Total intravenous anesthesia – A TIVA technique may be employed in selected patients participating in an ERAS protocol, particularly those at very high risk for postoperative nausea and vomiting (PONV) [38]. Although a propofol-based TIVA technique may result in a reduced incidence of PONV compared with inhalation anesthesia [39,40], data are not consistent. One 2016 meta-analysis found no overall difference in risk of PONV when TIVA was compared with an inhalation technique if at least one prophylactic antiemetic agent was administered [41]. (See "Postoperative nausea and vomiting", section on 'Prevention'.)

A typical TIVA technique includes infusion of propofol 75 to 150 mcg/kg/minute, with titration based on neuromonitoring of the processed or unprocessed EEG, with alarms set to detect high EEG indices that indicate possible awareness. A remifentanil infusion is typically selected for the opioid component of a TIVA technique for ERAS procedures, with titration to achieve hemodynamic stability. (See "Maintenance of general anesthesia: Overview", section on 'Total intravenous anesthesia' and "Accidental awareness during general anesthesia", section on 'Brain monitoring'.)

Nitrous oxide — We routinely use N₂O for ERAS procedures. The amnestic and analgesic properties of N₂O reduce the requirements of other anesthetic and adjuvant agents [42]. Furthermore, N₂O facilitates both uptake and removal of the potent volatile inhalation anesthetics via its "second gas effect," thereby allowing rapid changes in anesthetic depth and rapid emergence from anesthesia [43]. (See "Inhalation anesthetic agents: Clinical effects and uses", section on 'Advantages' and "Inhalation anesthetic agents: Properties and delivery", section on 'Second gas effect'.)

Despite these beneficial effects, some clinicians avoid N₂O due to concerns regarding increased risk of PONV. However, the emetic effects of N₂O can be mitigated with use of prophylactic antiemetics [43-46]. Other concerns include the possibility of bowel distention during colorectal procedures due to expansion of closed spaces. However, several studies have noted that surgeons do not recognize a difference between conditions in patients receiving N₂O during colorectal surgery compared with patients not receiving N₂O [47-49]. (See "Inhalation anesthetic agents: Clinical effects and uses", section on 'Disadvantages and adverse effects'.)

Opioids — Opioids may increase risk for postoperative opioid-related adverse events such as nausea, vomiting, sedation, bladder dysfunction, and respiratory depression, and may increase potential for acute tolerance, delayed hyperalgesia, and paradoxical increases in postoperative pain and opioid dosing requirements [50,51]. Therefore, we avoid high doses of opioids and use opioid-sparing approaches to perioperative pain management. (See "Perioperative uses of intravenous opioids in adults: General considerations", section on 'Prevention and management of adverse opioid effects'.)

As noted above, a remifentanil infusion is typically selected for the opioid component of a TIVA technique. For other techniques, small bolus doses of an opioid (eg, fentanyl 25 to 50 mcg) may be administered during the intraoperative period if indicated (eg, when increased heart rate and/or blood pressure are noted), but we typically limit the dose (eg, ≤1 mcg/kg per hour of fentanyl). Once fentanyl requirements have exceeded 1 mcg/kg per hour, we typically treat hypertension (and/or tachycardia) with vasoactive agents such as beta blockers or vasodilators rather than with additional doses of an opioid.

Notably, intraoperative tachycardia and hypertension often occur due to causes other than pain. For example, during laparoscopic surgical procedures, factors such as increased intra-abdominal pressure, absorption of carbon dioxide (CO₂), and effects of surgical positioning may lead to tachycardia and/or hypertension. Increasing opioid dosing to treat such hyperdynamic responses is not appropriate, as discussed in a separate topic. (See "Anesthesia for patients with hypertension", section on 'Prevention and treatment of intraoperative hypertension'.)

Neuromuscular blocking agents — An NMBA is often administered to facilitate surgical exposure during laparoscopic or open surgical procedures [52,53]. We avoid profound muscle paralysis by using a peripheral nerve stimulator to aim for a moderate level of neuromuscular blockade during laparoscopic procedures (eg, a train-of-four [TOF] count of 2 to 3). Even during laparoscopic abdominal surgery, we administer NMBAs as required by the clinical situation, aiming for the least degree of block necessary for the clinical situation. Detailed discussions regarding dosing and monitoring the effects of NMBAs are found in separate topics:

●(See "Clinical use of neuromuscular blocking agents in anesthesia", section on 'Facilitation of surgery'.)

●(See "Monitoring neuromuscular blockade", section on 'Train-of-four'.)

●(See "Anesthesia for laparoscopic and abdominal robotic surgery in adults", section on 'Neuromuscular blockade'.)

We avoid maintenance of deep neuromuscular blockade as this results in use of high doses of NMBAs and increased risk of residual muscle weakness at the end of the procedure (defined as a TOF ratio <0.9), even after reversal [54-56] (see "Clinical use of neuromuscular blocking agents in anesthesia", section on 'Avoidance of residual neuromuscular blockade'). Furthermore, one study noted that persistent impairment of the peripheral chemoreflex with blunting of the ventilatory response to hypoxia often occurs despite complete reversal of rocuronium with neostigmine or sugammadex [57]. These effects may increase the risk for serious adverse respiratory events [55,58]. Approaches to reducing residual effects of NMBAs include using the smallest dose of an NMBA that provides optimal surgical conditions, avoiding use of long-acting NMBAs, and ensuring complete reversal of any residual neuromuscular blockade near the end of the surgical procedure. Dosing of the reversal agents neostigmine or sugammadex is based on the degree of residual neuromuscular block at the time the agent is administered. Details regarding timing and adequacy of reversal of neuromuscular block are found in separate topics:

●(See "Emergence from general anesthesia", section on 'Assess and reverse effects of neuromuscular blocking agents'.)

●(See "Clinical use of neuromuscular blocking agents in anesthesia", section on 'Reversal of neuromuscular block'.)

●(See "Respiratory problems in the post-anesthesia care unit (PACU)", section on 'Neuromuscular blocking agents'.)

Mechanical ventilation — Intraoperative lung protective mechanical ventilation reduces postoperative pulmonary complications, length of hospital stay, and mortality after major surgery [59]. (See "Ventilator-induced lung injury" and "Clinical and physiologic complications of mechanical ventilation: Overview".)

●Maintenance phase of general anesthesia – Optimal lung protective parameters include (see "Mechanical ventilation during anesthesia in adults", section on 'Lung protective ventilation during anesthesia'):

•Low tidal volumes (ie, 6 to 8 mL/kg IBW). (See "Mechanical ventilation during anesthesia in adults", section on 'Tidal volume'.)

•Initial positive end-expiratory pressure (PEEP) 5 cm H₂O (or 8 to 10 cm H₂O during laparoscopic procedures). However, as surgery progresses, PEEP should be individualized based on patient and surgical factors, in an attempt to avoid both alveolar overdistention and atelectasis. In addition to patients undergoing laparoscopic procedures, those who are obese or undergoing surgery performed in steep Trendelenburg position may need levels of PEEP >5 cm H₂O. (See "Mechanical ventilation during anesthesia in adults", section on 'Positive end-expiratory pressure' and "Mechanical ventilation during anesthesia in adults", section on 'Individualized PEEP'.)

•Plateau pressure ≤16 mmHg and driving pressure (defined as the difference between plateau pressure and PEEP) ≤16 mmHg. (See "Mechanical ventilation during anesthesia in adults", section on 'Plateau pressure' and "Mechanical ventilation during anesthesia in adults", section on 'Driving pressure' and "Mechanical ventilation during anesthesia in adults", section on 'Monitoring driving pressure'.)

•Fraction of inspired oxygen (FiO₂) 0.4 to 0.5. (See "Mechanical ventilation during anesthesia in adults", section on 'Fraction of inspired oxygen'.)

•Initial respiratory rate of 8 breaths/minute, subsequently adjusted to maintain end-tidal carbon dioxide (ETCO₂) levels at approximately 40 mmHg (rather than traditional values of 30 to 35 mmHg). These higher CO₂ level may increase tissue perfusion and oxygenation, due to an increase in cardiac output and vasodilation, and a rightward shift of the oxyhemoglobin dissociation curve. (See "Mechanical ventilation during anesthesia in adults", section on 'Respiratory rate' and "Mechanical ventilation during anesthesia in adults", section on 'Goal end-tidal carbon dioxide'.)

•Performance of recruitment maneuvers only when indicated to improve oxygenation (eg, in an obese patient), or in specific circumstances (eg, after insufflation for laparoscopy or disconnection from the ventilator for suctioning). (See "Mechanical ventilation during anesthesia in adults", section on 'Recruitment maneuvers'.)

During laparoscopic procedures, high peak airway pressures and/or desaturation may necessitate temporary modifications in these ventilator settings. (See "Anesthesia for laparoscopic and abdominal robotic surgery in adults", section on 'Mechanical ventilation'.)

●Emergence from general anesthesia – During emergence, we maintain minute ventilation in an effort to eliminate inhalation anesthetics and facilitate rapid emergence. Although some clinicians reduce the respiratory rate near the end of the procedure in an effort to increase ETCO₂ levels to simulate respiration, this reduction of respiratory rate and minute ventilation can delay removal of inhalation anesthetic agents, thereby delaying emergence. (See "Emergence from general anesthesia", section on 'Preparations for emergence'.)

Fluid management — Intraoperative fluid management is aimed at restoring and maintaining euvolemia. (See "Intraoperative fluid management", section on 'Choosing a fluid management strategy'.)

We typically use a zero-balance fluid therapy approach that minimizes fluid administration for minimally or moderately invasive surgery for patients participating in an ERAS protocol. We administer a balanced electrolyte solution (eg, Ringer's lactate) at 3 mL/kg/hour. We do not "preload" fluid prior to neuraxial block or induction of general anesthesia, or replace urine output, calculated insensible losses, or nonanatomic "third space" losses [60]. (See "Intraoperative fluid management", section on 'Restrictive (zero-balance) strategy' and "Intraoperative fluid management", section on 'Minimally/moderately invasive surgery'.)

For high-risk patients undergoing major surgical procedures that dictate arterial catheter placement, this approach is supplemented with goal-directed fluid therapy, particularly if significant blood losses (eg, >500 mL) and/or fluid shifts are expected. With this approach, supplemental fluid boluses (typically 200 to 250 mL) are administered based on information derived from invasive dynamic hemodynamic parameters such as manual estimation or automated calculation of variations in systolic blood pressure or pulse pressure in the intraarterial waveform tracing, or variations in stroke volume. Further details are available in a separate topic:

●(See "Intraoperative fluid management", section on 'Major invasive surgery'.)

●(See "Intraoperative fluid management", section on 'Goal-directed fluid therapy'.)

●(See "Intraoperative fluid management", section on 'Dynamic parameters to assess volume responsiveness'.)

For patients participating in ERAS protocols and other surgical patients, evidence suggests that these fluid management strategies (zero-balance or goal-directed approaches) are superior to traditional approaches that use liberal fluid administration based on a fixed volume resulting in administration of excessive volumes of crystalloid solution and increased risk for tissue edema and associated adverse outcomes. (See "Intraoperative fluid management", section on 'Avoid traditional liberal or fixed-volume approaches'.)

Temperature control — Core body temperature is routinely monitored at the esophageal or nasopharyngeal site, and warming devices are employed to maintain normothermia (temperature ≥35.5°C) [61-64]. These include upper- and lower-body forced-air warming devices and blankets, insulation water mattresses, and devices for warming all IV fluids. (See "Perioperative temperature management", section on 'Intraoperative hypothermia'.)

Hypothermia is avoided because of potential complications in the immediate- and long-term postoperative periods (eg, shivering, coagulopathy, prolonged duration of stay in the post-anesthesia care unit (PACU), surgical site infection, adverse cardiac events) [64]. (See "Perioperative temperature management", section on 'Postoperative temperature derangements'.)

Glycemic control — Perioperative glycemic control is initiated in the preoperative period, including appropriate advice to diabetic patients regarding hypoglycemic drugs and insulin administration. Perioperative blood glucose levels are monitored and maintained between 140 and 200 mg/dL (7.8 to 11 mmol/L) in both diabetic and nondiabetic patients throughout the perioperative period. More aggressive control is avoided as this incurs risk of hypoglycemia and associated perioperative complications. (See "Perioperative management of blood glucose in adults with diabetes mellitus".)

Antiemetic prophylaxis — We routinely use multimodal antiemetic prophylaxis in all patients participating in ERAS protocols to facilitate early recovery [38]. Although selective risk-based approaches for antiemetic therapy have been proposed, compliance with these strategies may be poor [65]. (See "Postoperative nausea and vomiting", section on 'Risk stratification'.)

We typically use a combination of IV dexamethasone 8 to 10 mg administered after induction of anesthesia, as well as a 5-hydroxytryptamine type 3 (5-HT3) antagonist such as IV ondansetron 4 mg administered at the end of the surgical procedure. Administration of a higher perioperative dose of dexamethasone 0.2 mg/kg did not reduce a composite of serious complications (eg, organ failure) compared with placebo in a trial of more than 1200 patients undergoing major noncardiac surgery, but increased risk for hyperglycemia requiring insulin therapy [66].

For patients at very high risk of PONV (eg, history of motion sickness, history of previous PONV, known high opioid requirements for pain relief), we administer an additional antiemetic agent such as preoperative transdermal scopolamine or intraoperative IV haloperidol 0.5 to 1 mg administered shortly after induction of anesthesia. Notably, use of more than three antiemetics has not been shown to confer additional clinical benefit [67]. In addition, a TIVA technique may be used for such high-risk patients. (See "Postoperative nausea and vomiting", section on 'Antiemetics'.)

Pain prophylaxis — Postoperative multimodal pain management is patient-specific and procedure-specific, with the goal of minimizing pain during rest and also during early mobilization and physical therapy. Combinations of the following agents and techniques may be used to balance analgesic efficacy with overall side effects in multimodal strategies [13] (see "Approach to the management of acute pain in adults", section on 'Creating a plan for analgesia'):

●Nonopioid analgesics – We employ combinations of acetaminophen and a nonsteroidal antiinflammatory drug (NSAID) or a cyclooxygenase (COX)-2 specific inhibitor in multimodal pain management protocols for all patients who have no contraindications (see "Nonselective NSAIDs: Overview of adverse effects" and "Anesthesia for the patient with liver disease", section on 'Other analgesics') [13,68-71]. We typically administer oral acetaminophen two hours preoperatively; IV acetaminophen 1 g is administered after induction of anesthesia only if the patient did not receive preoperative acetaminophen.

Administration of NSAIDs is typically avoided until the surgical procedure itself has been completed (late during the intraoperative period or in the postoperative period) due to antiplatelet effects that may increase risk of perioperative bleeding. We typically administer IV ketorolac 15 to 30 mg (if no contraindications) near the end of the surgical procedure. However, COX-2 specific inhibitors spare the COX-1 enzyme and have no antiplatelet effects; thus, these agents may be administered earlier (in the preoperative period) if desired. Oral or IV preparations of acetaminophen and NSAIDs or COX-2 specific inhibitors are then continued in the postoperative period with regular scheduled dosing.

Although most experts recommend such combinations of an NSAID plus acetaminophen [13,68], only heterogeneous evidence of the efficacy of this approach exists because of differences in the types of surgical procedures studied, specific agents used, and dosing and timing of administration of these agents. One 2013 meta-analysis included three trials with 1647 total patients who received a combination of differing doses of ibuprofen and acetaminophen, ibuprofen alone, or placebo, with agent(s) administered only once in the perioperative period during various types of surgical procedures [69]. The proportion of patients achieving at least 50 percent maximum pain relief over six postoperative hours ranged from 69 to 73 percent with this combination (depending on the dose of each drug) compared with only 7 percent of those receiving placebo, and only 52 percent of those receiving ibuprofen alone. No significant adverse events were reported in any of the included studies [69]. Similarly, an older meta-analysis of 21 trials (2909 patients) that compared acetaminophen alone or in combination with one of several NSAIDs (ibuprofen, diclofenac, ketoprofen, ketorolac, aspirin, tenoxicam, or rofecoxib), noted that combinations of these agents were more effective than either agent alone [71].

Additional considerations regarding administration of NSAIDs and acetaminophen are discussed in other sections of this topic and elsewhere:

•(See 'Medications administered in the preoperative period' above.)

•(See 'Management of pain' below.)

•(See "Nonopioid pharmacotherapy for acute pain in adults", section on 'Acetaminophen'.)

•(See "Nonopioid pharmacotherapy for acute pain in adults", section on 'Nonsteroidal anti-inflammatory drugs'.)

●Local or regional anesthetic techniques – A local or regional anesthetic technique is often employed as a primary component of a multimodal analgesic regimen [13,72,73].

•Local infiltration or surgical field block – Infiltration of the surgical wound with local anesthetic provides excellent analgesia that outlasts the duration of action of the drug; therefore, this technique is used whenever possible [74]. Attention to proper infiltration technique (ie, infiltration into the peritoneal, musculofascial, and subdermal tissue planes) is essential to attain the maximum benefits. Catheters may be placed by the surgeon directly at the site of the incision and can be left in place for days [73]. (See "Approach to the management of acute pain in adults", section on 'Wound infiltration'.)

An alternative is an interfascial plane block such as the transversus abdominis plane (TAP) blocks, which provide excellent pain relief after laparoscopic or open lower (below the umbilicus) abdominal surgical procedures such as total abdominal hysterectomy. However, a TAP block is unlikely to be superior to surgical site infiltration after a laparoscopic procedure with a small incision [72]. (See "Transversus abdominis plane (TAP) blocks procedure guide".)

New interfascial plane blocks are emerging (eg, quadratus lumborum, serratus plane, and erector spinae plane blocks). Erector spinae plane blocks provide somatic as well as visceral analgesia, and may be superior to peripheral interfascial plane blocks (eg, the TAP block) [72]. Details regarding placement of these blocks are available in separate topics:

-(See "Erector spinae plane block procedure guide".)

-(See "Thoracic nerve block techniques", section on 'Serratus plane block'.)

-(See "Quadratus lumborum block procedure guide".)

Some clinicians use long-acting liposomal bupivacaine, which has been approved by the US Food and Drug Administration, for local infiltration at the surgical wound site. (See "Clinical use of local anesthetics in anesthesia", section on 'Sustained release bupivacaine'.)

•Peripheral nerve blocks – Peripheral nerve blocks for the lower extremity (eg, femoral nerve block) are not used commonly due to concern regarding delays in ambulation and recovery. Furthermore, since single injection peripheral nerve blocks have a short duration of action, rebound pain may occur after the block has resolved. However, brachial plexus blocks are still used for upper extremity surgery, and popliteal sciatic nerve block are suitable for selected foot and ankle procedures [13]. (See "Approach to the management of acute pain in adults", section on 'Regional anesthesia techniques'.)

•Neuraxial analgesia – We do not use epidural analgesia in ERAS patients undergoing minimally invasive procedures (eg, laparoscopic surgery) because of potential delays in ambulation and hospital discharge due to adverse side effects that may include postural hypotension, need for a urinary catheter, or inadequate muscle strength. Also, there is little additional benefit for pain control since alternative analgesic techniques provide similar pain relief (eg, interfascial plane blocks) [13]. In particular, we avoid administration of an intrathecal opioid such as morphine for any ERAS procedure due to high risk for adverse effects including nausea, vomiting, pruritus, urinary retention, and respiratory depression.

Although epidural analgesia provides excellent pain relief after major open thoracic and abdominal surgical procedures, it is unnecessary after less invasive surgical approaches [13]. Rarely, thoracic epidural analgesia is used to prevent or treat pain after an open procedure with a long midline incision (eg, from the xiphoid process to the pubis). Such use is typically supplemented with a TAP block for the subumbilical portion of the incision.

●Fixed dose of a long-acting opioid – For patients who did not receive a regional anesthetic technique, ERAS protocols include a precalculated dose of a long-acting opioid for most open surgical procedures. We use morphine 0.05 to 0.1 mg/kg IBW or hydromorphone 5 to 10 mcg/kg IBW administered approximately 20 minutes prior to the expected time of extubation (eg, when the surgeon starts closing the abdomen). This approach does not delay awakening or tracheal extubation [75]. Some clinicians attempt to titrate a long-acting opioid to produce a respiratory rate of approximately 12 to 15 breaths per minute during emergence from anesthesia, but potential residual effects of anesthetic agents and NMBAs make this approach challenging.

Long-acting opioids are always used sparingly due to opioid-related adverse effects that delay recovery and return to activities of daily living (eg, delayed emergence from anesthesia, postoperative respiratory depression, delirium, PONV, urinary retention necessitating bladder catheterization, pruritus, development of acute tolerance or hyperalgesia) [25,50,51]. (See "Perioperative uses of intravenous opioids in adults: General considerations", section on 'Dosing considerations' and "Perioperative uses of intravenous opioids in adults: General considerations", section on 'Prevention and management of adverse opioid effects'.)

●Adjunct agents

•Dexamethasone – As noted above, we routinely administer IV dexamethasone 8 to 10 mg after induction of anesthesia to all patients unless there are contraindications, due to its antiemetic prophylactic effects (see 'Antiemetic prophylaxis' above), but it also has analgesic properties [76,77]. Potential concerns regarding increases in blood glucose and surgical site infections have not been observed in large observational studies [78,79].

•Ketamine – We do not routinely use intraoperative ketamine to achieve postoperative analgesia. Although administration of a low dose of ketamine (25 to 50 mg) after induction of anesthesia has been reported to improve postoperative pain relief [80], adverse psychotomimetic effects such as hallucinations, nightmares, or vivid dreams during and shortly after emergence from anesthesia limit its use in ERAS protocols [13,81,82].

POSTOPERATIVE ANESTHETIC MANAGEMENT — Postoperative goals in ERAS protocols include prevention and relief of pain and postoperative nausea or vomiting (PONV), as well as facilitation of early nutrition and mobilization [83].

Management of pain — While the patient is in the post-anesthesia care unit (PACU), pain is treated with small bolus doses of either intravenous (IV) morphine 1 to 2 mg doses (up to 10 mg) or IV hydromorphone 0.1 to 0.2 mg (up to 1 mg).

Subsequently, we use scheduled doses of oral acetaminophen 1 g four times per day and an oral nonsteroidal antiinflammatory drug (NSAID; eg, meloxicam 15 mg once per day) or oral cyclooxygenase (COX)-2 specific inhibitor (eg, celecoxib 200 mg twice per day) [13,68-70]. For patients who do not yet tolerate oral liquids, acetaminophen, ibuprofen, and ketorolac are each available in an IV formulation. (See "Nonopioid pharmacotherapy for acute pain in adults".)

For major open surgical procedures with a high likelihood of persistent postoperative pain, we also use oral gabapentin 300 mg three times per day [12,13]. As noted above (see 'Medications administered in the preoperative period' above), we avoid gabapentin in older patients and those with sleep-disordered breathing (eg, obstructive sleep apnea) due to concerns regarding excessive sedation, ventilatory depression, and dizziness [14-17].

We administer oral oxycodone 5 to 10 mg four times per day as needed for breakthrough pain. For patients unable to take oxycodone, we use tramadol 50 mg four times per day as needed. If a patient is unable to take oral medications or has severe pain, small bolus doses of IV morphine (2 to 3 mg) or hydromorphone (0.5 mg) may be administered as needed. In rare circumstances, it may be necessary to administer IV opioids via IV patient-controlled analgesia to achieve control of postoperative pain. (See "Use of opioids for postoperative pain control".)

Management of nausea and vomiting — For patients requiring postoperative rescue antiemetic therapy to treat PONV, we typically administer IV promethazine 6.25 mg and/or ondansetron 4 mg (no earlier than four hours after an intraoperative ondansetron dose) and/or dimenhydrinate 1 mg/kg. (See "Postoperative nausea and vomiting".)

Observation for cardiopulmonary problems — Even after minimally invasive surgery and adherence to an ERAS protocol, observation and prompt treatment of postoperative problems such as hypoxemia or orthostatic hypotension is necessary [84,85].

OUTCOMES — Data from observational studies and randomized trials in patients undergoing colorectal surgery show that ERAS protocols are associated with reduced hospital length of stay and morbidity, reduced postoperative pain, faster recovery, comparable or reduced readmission rate, and cost savings compared with traditional care. Adherence to a standardized ERAS protocol impacts outcomes such as complications and length of hospital stay [27,86,87]. Further discussion regarding these outcomes is available in a separate topic. (See "Enhanced recovery after colorectal surgery", section on 'Outcomes'.)

Similarly, studies in various types of gynecologic surgery have noted that ERAS protocols are associated with decreased pain, length of stay, use of nursing time, and overall costs, thereby improving patient satisfaction and quality of life. (See "Enhanced recovery after gynecologic surgery: Components and implementation", section on 'Outcomes'.)

Short- and long-term postoperative outcomes are influenced by anesthesia-related management as part of a multidisciplinary team effort during the preoperative, intraoperative, and postoperative periods [3,6,28].

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: Postoperative nausea and vomiting" and "Society guideline links: Enhanced recovery after surgery".)

SUMMARY AND RECOMMENDATIONS

●Preoperative considerations – Management to facilitate enhanced recovery after surgery (ERAS) emphasizes (table 1) (see 'Preoperative considerations' above):

•Identifying comorbidities and opportunities to optimize preoperative condition

•Minimizing the fasting period and maintaining hydration during the fasting period

•Educating patient and family to reduce patient anxiety and set realistic expectations, particularly regarding plans for pain management

●Preoperative medications – Medications for ERAS protocols given in the preoperative period typically include oral acetaminophen 1 g and a cyclooxygenase (COX)-2 specific inhibitor (eg, celecoxib 400 mg) administered at least two hours preoperatively for patients without contraindications to these agents. Oral gabapentin is reserved for selected patients undergoing surgical procedures with a high risk of persistent postoperative pain (300 to 600 mg administered at least two hours preoperatively). Also, thromboprophylaxis with subcutaneous heparin 5000 units is administered 30 to 60 minutes before surgery. We avoid routine administration of benzodiazepine premedication. (See 'Medications administered in the preoperative period' above.)

●Anesthetic induction – A typical anesthetic induction sequence includes intravenous (IV) fentanyl approximately 0.5 to 1 mcg/kg ideal body weight (IBW), given three to five minutes prior to lidocaine 20 to 30 mg, followed by propofol 1 to 1.5 mg/kg to achieve loss of eyelash reflex and/or response to verbal command. In addition, a nondepolarizing neuromuscular blocking agent (NMBA) such as rocuronium 0.6 to 1 mg/kg IBW may be administered to facilitate laryngoscopy and endotracheal intubation. (See 'Induction of anesthesia' above.)

●Anesthetic maintenance – During maintenance of anesthesia, we prefer an inhalation-based technique with a potent volatile agent (desflurane or sevoflurane) and nitrous oxide (N₂O) 50 percent in oxygen to achieve an age-adjusted minimum alveolar concentration (MAC) value of approximately 0.8 to 1.0, and we avoid deep anesthesia. A total intravenous anesthesia (TIVA) technique is a reasonable alternative for selected patients (eg, those at very high risk for postoperative nausea and vomiting [PONV]). (See 'Inhalation versus total intravenous anesthesia techniques' above.)

We use short-acting agents administered at the lowest possible doses:

•Small bolus doses of an opioid (eg, fentanyl 25 to 50 mcg) may be administered as needed, but we typically limit the dose (eg, ≤1 mcg/kg per hour fentanyl). For TIVA techniques, a remifentanil infusion is typically selected for the opioid component. (See 'Opioids' above.)

•We routinely use N₂O for ERAS procedures. Its amnestic and analgesic properties reduce the requirements of other anesthetic and adjuvant agents, and its "second gas effect" facilitates both uptake and removal of the potent volatile inhalation anesthetics. (See 'Nitrous oxide' above.)

•An NMBA is often administered to facilitate surgical exposure, but we monitor the effects of the NMBA with a peripheral nerve stimulator to avoid profound muscle paralysis. (See 'Neuromuscular blocking agents' above.)

●Lung-protective ventilation – We use lung protective ventilatory parameters including low tidal volumes (ie, 6 to 8 mL/kg IBW), initial positive end-expiratory pressure (PEEP) 5 cm H₂O (or 8 to 10 cm H₂O during laparoscopic procedures), plateau pressures ≤16 mmHg, driving pressure (defined as the difference between plateau pressure and PEEP) ≤16 mmHg, fraction of inspired oxygen (FiO₂) 0.4 to 0.5, and an initial respiratory rate of 8 breaths/minute, subsequently adjusted to maintain end-tidal carbon dioxide (ETCO₂) levels at approximately 40 mmHg. (See 'Mechanical ventilation' above.)

●Fluid management – We typically use a zero-balance fluid therapy approach that minimizes fluid administration for minimally or moderately invasive surgery with administration of a balanced electrolyte solution at 3 mL/kg/hour. For high-risk patients undergoing major surgical procedures, this approach is supplemented with goal-directed fluid therapy with administration of fluid boluses (typically 200 to 250 mL) based on dynamic hemodynamic parameters. (See 'Fluid management' above.)

●Maintenance of normothermia – Core body temperature is routinely monitored and warming devices are employed to maintain normothermia (temperature ≥35.5°C). (See 'Temperature control' above.)

●Glycemic control – Perioperative blood glucose levels are monitored and maintained between 140 and 200 mg/dL (7.8 to 11 mmol/L) in both diabetic and nondiabetic patients. (See 'Glycemic control' above.)

●Antiemetic prophylaxis – Antiemetic prophylaxis includes IV dexamethasone 8 to 10 mg after induction of anesthesia and ondansetron 4 mg at the end of surgery. For patients at very high risk of PONV, we add a third antiemetic (eg, preoperative transdermal scopolamine patch or intraoperative IV haloperidol 0.5 to 1 mg shortly after induction). Postoperative rescue antiemetic therapy to treat PONV includes IV promethazine 6.25 mg and/or ondansetron 4 mg (no earlier than four hours after an intraoperative ondansetron dose) and/or dimenhydrinate 1 mg/kg. (See 'Antiemetic prophylaxis' above and 'Management of nausea and vomiting' above.)

●Multimodal pain management – We employ intraoperative and postoperative multimodal pain prophylaxis and management strategies that minimize perioperative opioid use including (see 'Pain prophylaxis' above and 'Management of pain' above):

•We suggest administration of a combination of acetaminophen and a nonsteroidal antiinflammatory drug (NSAID) or a COX-2 specific inhibitor (Grade 2B). We typically administer acetaminophen 1 g IV shortly after induction of anesthesia (if not previously administered in the preoperative period), as well as a NSAID such as ketorolac 15 to 30 mg IV at the end of surgery.

•Local or regional techniques, such as surgical site infiltration and interfascial plane blocks. However, we avoid epidural analgesia and intrathecal morphine because of potential delays in ambulation and hospital discharge without additional benefits for pain control.

•For patients undergoing open procedures without a regional anesthetic technique, administration of a precalculated dose of a long-acting opioid approximately 20 minutes before extubation (eg, morphine 0.05 to 0.1 mg/kg IBW or hydromorphone 5 to 10 mcg/kg IBW).

•For pain while the patient is in the post-anesthesia care unit (PACU), administration of small bolus doses of either IV morphine 1 to 2 mg doses (up to 10 mg) or IV hydromorphone 0.1 to 0.2 mg (up to 1 mg).

•Subsequently, we use scheduled doses of oral acetaminophen 1 g four times per day and an oral NSAID (eg, meloxicam 15 mg once per day) or oral COX-2 specific inhibitor (eg, celecoxib 200 mg twice per day). For patients who do not yet tolerate oral liquids, acetaminophen, ibuprofen, and ketorolac are each available in an IV formulation.