Enhanced recovery after colorectal surgery

INTRODUCTION — Enhanced recovery programs are evidence-based protocols designed to standardize medical care, improve outcomes, and lower health care costs. These protocols include evidence-based techniques to minimize surgical trauma and postoperative pain, reduce complications, improve outcomes, and decrease hospital length of stay while expediting recovery following elective procedures.

Multimodal enhanced recovery after surgery (ERAS) is an integrated, multidisciplinary approach that requires participation and commitment from the patient, surgeons, anesthesiologists, pain specialists, nursing staff, physical and occupational therapists, social services, and hospital administration [1,2]. Initially, ERAS protocols converted many operations performed as inpatient to outpatient "day surgery" procedures. As experience developed with these protocols, principles of enhanced recovery were applied to increasingly complex procedures to reduce hospital length of stay and expedite return to baseline health and functional status [2,3].

ERAS protocols have been developed for colorectal surgery patients to reduce physiological stress and postoperative organ dysfunction through optimization of perioperative care and recovery [1,2,4]. Typically, such protocols include perioperative opioid-sparing analgesia, a laparoscopic approach for the colorectal resection, avoidance of nasogastric tubes and peritoneal drains, aggressive management of postoperative nausea and vomiting, and early oral feedings and ambulation (table 1) [5].

This topic will discuss preoperative, intraoperative, and postoperative strategies used in ERAS protocols developed for colorectal surgery. Other aspects of colorectal surgery are reviewed separately. (See "Overview of colon resection" and "Radical resection of rectal cancer" and "Surgical treatment of rectal cancer".)

ELEMENTS OF ERAS — The goals of enhanced recovery after surgery (ERAS) protocols include attenuating the surgical stress response and reducing end organ dysfunction through integrated preoperative, intraoperative, and postoperative pathways. Discharge criteria with ERAS are similar to those of traditional care, but patients receiving ERAS care meet these discharge criteria sooner [1,2].

ERAS protocols typically include 15 to 20 elements or components combined to form a multimodal pathway. These elements span through the continuum of the preoperative, intraoperative, and postoperative periods. Separately, individual elements result in modest gains, but when used together in a complementary fashion, they can decrease postoperative stress responses, thereby reducing duration of postoperative ileus, surgical complications, incisional pain, recovery time, and length of hospital stay [1,2,6,7]. Of the 15 to 20 recommended elements, the relative contribution of each individual element is unknown [8,9].

Preoperative strategies — Preoperative strategies of ERAS protocols involve medical risk evaluation, prehabilitation, patient education including stoma management, mechanical bowel preparation, and fasting policies.

Medical risk evaluation and interventions — ERAS programs require optimization of medical comorbidities, including cardiovascular, respiratory, and/or renal disease, as discussed in separate topics:

●(See "Evaluation of cardiac risk prior to noncardiac surgery".)

●(See "Management of cardiac risk for noncardiac surgery".)

●(See "Evaluation of perioperative pulmonary risk".)

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

Also, social and behavioral factors, such as illicit drug use, tobacco smoking, and alcohol dependency, should be addressed.

Prehabilitation — For older and frail adult patients, prehabilitation has shown some benefit [10]. In a randomized trial of 251 patients undergoing colorectal surgery for cancer, a four-week supervised multimodal prehabilitation program consisting of a high-intensity exercise three times per week, nutritional intervention, psychological support, and a smoking cessation program when needed reduced severe complication rate (30 versus 17 percent) and medical complication rate (27 versus 15 percent) [11].

Strategies of prehabilitation for surgical patients are discussed elsewhere. (See "Overview of prehabilitation for surgical patients".)

Patient education and ostomy site selection — Patient education, including discussions regarding ostomy site selection if needed, routine postoperative care, recovery milestones, and a review of signs and symptoms that warrant a postdischarge surgical evaluation, helps patients adhere to an ERAS program [4]. (See "Overview of surgical ostomy for fecal diversion", section on 'Preparation and counseling'.)

A United States consensus panel identified a list of warning indicators that should be provided to patients to educate them as to when they should contact their surgeon following hospital discharge after a colorectal procedure [12]. The warning indicators include:

●Wound drainage

●Wound erythema or changes in the skin around the wound

●No bowel movement or lack of flatus per rectum or ostomy for more than 24 hours

●Increasing abdominal pain

●Vomiting

●Abdominal swelling

●High ostomy output and/or dark or no urine

●Fever greater than 101.5°F (38.6°C)

●Inability to take in liquids or solid foods for more than 24 hours

●Shortness of breath

●Chest pain

Bowel preparation — We suggest performing mechanical bowel preparation combined with oral antibiotics for all patients undergoing elective colorectal resection, based on the preponderance of data [13,14]. Others choose to omit bowel preparation [15-17]. Since data regarding bowel preparation are mixed, mechanical bowel preparation and oral antibiotics will continue to be used at the discretion of the surgeon, regardless of whether they are a part of an ERAS protocol. Specific aspects of bowel preparation for elective colorectal surgery are discussed further in another topic. (See "Overview of colon resection", section on 'Bowel preparation'.)

Fasting guidelines — Fasting reduces the risk of aspiration of gastric contents during a general anesthetic by reducing gastric volume and acidity. Preoperative fasting guidelines have been established by the American Society of Anesthesiologists (ASA) and are based upon randomized trials and nonrandomized comparative studies [18]. (See "Preoperative fasting in adults".)

Clear liquids — The ASA guidelines recommend fasting for at least two hours from clear liquids and all other intake, including medicines [19]. Patients may consume clear liquids, including nonalcoholic beverages such as water, juices without pulp, coffee or tea without milk, and carbohydrate drinks, up until two hours before surgery. This approach to fasting helps avoid symptoms of dehydration, hypoglycemia, and caffeine withdrawal. (See "Preoperative fasting in adults", section on 'Clear liquids'.)

For ERAS protocols, it is critical to minimize the fasting period; thus, we encourage patients to consume clear liquids until two hours prior to surgery to remain hydrated. Typically, we advise patients to drink at least two glasses of water before going to bed the night before surgery 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 [20].

Carbohydrate-rich drink — Some ERAS protocols prescribe a carbohydrate-rich drink two hours prior to surgery, but not others. This practice has been suggested as a method to convert the patient from the "fasted" to the "fed" state, reducing postoperative insulin resistance and postoperative weight loss [21]. Evidence to support carbohydrate-rich drinks before elective colon surgery is limited [21-23]. In a randomized trial of nondiabetic patients undergoing major abdominal surgery, preoperative oral intake of 800 mL of water containing 100 g of carbohydrates decreased the incidence of postoperative hyperglycemia (blood glucose >180 mg/dL) requiring insulin but not the risk of postoperative infection [24].

Solid foods and milk — The following ASA guidelines are applicable to solid foods and milk (see "Preoperative fasting in adults", section on 'Solid foods'):

●Fried or fatty foods or meat – ASA guidelines recommend that patients fast eight hours or more following intake of fried or fatty foods or meat due to prolonged gastric emptying time.

●Light meal or milk – ASA guidelines recommend that patients fast six hours or more following ingestion of a light meal (eg, toast and tea) or milk.

Alvimopan — Prolonged postoperative ileus is a main cause of delayed patient recovery, and reducing this complication is a specific objective of ERAS protocols. The pathogenesis, clinical manifestations, prevention (eg, reduction in opioid use), and management (eg, nasogastric suction, reduction of opioid use) of ileus are reviewed elsewhere. (See "Postoperative ileus" and "Measures to prevent prolonged postoperative ileus".)

Alvimopan, an oral peripherally acting mu-opioid receptor antagonist (PAM-OR) that has a limited ability to cross the blood-brain barrier, appears to reduce prolonged ileus after bowel and gynecologic surgery [25]. The benefits of alvimopan are questionable when nonopioid analgesics and other perioperative opioid-sparing techniques are employed. Alvimopan is used in some ERAS protocols (primarily in the United States) but not others.

When administration is planned, alvimopan should be started preoperatively to be effective. Use of alvimopan to accelerate recovery after gastrointestinal surgery is further discussed elsewhere. (See "Measures to prevent prolonged postoperative ileus", section on 'Peripheral acting mu-opioid receptor antagonists'.)

Intraoperative strategies — Intraoperative strategies in ERAS protocols include selection of anesthetic agents and techniques, lung-protective ventilation, fluid management, temperature regulation, and choice of the surgical approach.

Selection of anesthetic agents — Newer anesthetic agents and advances in agents and techniques have facilitated implementation of ERAS protocols for colorectal surgery. Long-acting anesthetic agents should be avoided, and multimodal analgesic strategies should be favored. (See 'Pain management' below.)

Typical anesthetic regimens include:

●Use of only short-acting anesthetic agents (eg, propofol, inhaled anesthetics such as sevoflurane or desflurane) that are administered at the lowest possible doses. (See "Maintenance of general anesthesia: Overview", section on 'Selection of maintenance techniques'.)

●Avoidance of premedication with midazolam to reduce the risk of dose-dependent postoperative sedation and respiratory depression, particularly if opioids are administered [26-28].

●Avoidance of long-acting opioids and reduction of total intraoperative opioid doses (figure 1 and table 2). (See "Perioperative uses of intravenous opioids in adults: General considerations".)

●Avoidance of long-acting neuromuscular blocking agents (NMBAs) and use of a peripheral nerve stimulator to avoid profound muscle paralysis (table 3). Residual effects of an NMBA should be appropriately reversed at the end of surgery (see "Emergence from general anesthesia", section on 'Assess and reverse effects of neuromuscular blocking agents'). Persistent muscle weakness often leads to postoperative respiratory complications. (See "Overview of the management of postoperative pulmonary complications".)

Lung-protective ventilation — The primary goals for intraoperative ventilation are to provide nonharmful ventilation that opens the lungs and keeps them open into the postoperative period. We suggest the use of lung-protective ventilation for all patients who receive mechanical ventilation during anesthesia. For most patients, we suggest low tidal volumes of 6 to 8 mL/kg, initial positive end-expiratory pressure (PEEP) of 5 cm H₂O (10 cm H₂O during laparoscopy), and plateau pressures ≤16 mmHg. (See "Mechanical ventilation during anesthesia in adults", section on 'Lung protective ventilation during anesthesia'.)

Intraoperative fluid management — Intraoperative fluid management is aimed at restoring and maintaining euvolemia. Commonly used strategies have included (see "Intraoperative fluid management", section on 'Choosing a fluid management strategy'):

●Restrictive fluid therapy (ie, zero-balance approach) avoids fluid overload by replacing only the fluid that is lost during surgery [29]. Given that the ERAS goals for perioperative fluid management include avoidance of either hypovolemia or excessive fluid administration that may result in pulmonary complications, we typically use restrictive fluid therapy to minimize fluid administration, rather than the other two strategies [29-32]. In one randomized multicenter trial of 150 patients undergoing elective colorectal surgery, equivalent postoperative outcomes were noted with a zero-balance (restrictive) approach compared with a goal-directed approach to fluid therapy [33].

●Goal-directed fluid therapy refers to the administration of fluids to achieve a certain physiologic goal (eg, stroke volume variation, systolic pressure variation, or pulse pressure variation). If preoperative dehydration is avoided and early postoperative alimentation is emphasized as part of an ERAS protocol, then goal-directed fluid therapy may be unnecessary because of the low risk of perioperative fluid imbalance [34-36]. A 2016 meta-analysis of randomized controlled trials of patients undergoing elective major abdominal surgery (2099 patients; 23 studies) noted no benefit when goal-directed fluid therapy was used within the setting of an ERAS protocol, compared with a fixed-volume regimen [37].

●Fixed-volume therapy is a traditional approach in which intraoperative fluid administration is based upon predetermined algorithms (eg, 4-2-1 rule). Fixed-volume therapy can lead to fluid overload.

In one study of 2900 patients undergoing elective colorectal surgery, total intraoperative fluid ≥2.7 L was independently associated with postoperative ileus and prolonged length of stay [38].

Temperature regulation — The authors monitor body temperature and routinely use body warmers for all patients undergoing colorectal surgery. Changes in body temperature that occur with exposure during the procedure and alterations in temperature regulation due to anesthetic agents may lead to coagulopathy, adverse cardiac events, and decreased resistance to surgical wound infections [39]. Data from a randomized trial demonstrated that intraoperative hypothermia prolonged the duration of time in the recovery room compared with routine thermal management (mean 94 versus 53 minutes) [40]. Hypothermia is most likely to occur when procedures are longer than two hours, in older adults, in those with little body fat, and in those with comorbid illnesses [40-43]. (See "Perioperative temperature management", section on 'Intraoperative hypothermia' and "Perioperative temperature management", section on 'Postoperative temperature derangements'.)

Minimally invasive surgery — Minimally invasive techniques are central to ERAS protocols because they decrease inflammatory mediator release, improve pulmonary function, expedite return of bowel function, and reduce length of hospital stay [44-51]. For patients with malignant diseases, the oncologic outcomes of laparoscopic colon surgery are comparable to those of open surgery. (See "Surgical resection of primary colon cancer", section on 'Open versus laparoscopic colectomy'.)

Several randomized trials have compared laparoscopic and open colorectal surgery with the utilization of an ERAS protocol. A meta-analysis of these trials concluded that laparoscopic surgery reduced both the length of hospital stay and the rate of complications [52].

When laparoscopic procedures are converted to open surgery, patient outcomes are not necessarily compromised. In a retrospective review of 2483 patients undergoing laparoscopic colorectal procedures, 11 percent required a conversion. Those who converted had similar 30 day mortality (0.4 versus 0 percent) and overall morbidity rates (27 percent in both groups) compared with those who completed the procedure laparoscopically [53].

Robotic colorectal surgery may offer additional benefit to patient recovery beyond conventional laparoscopic surgery.

Peritoneal drains — Peritoneal drains are not included in ERAS protocols. In the elective setting, drains do not reduce postoperative morbidity or mortality or ameliorate the effect of anastomotic leakage. Data are limited on the use of peritoneal drains in emergency settings. Further discussion on the use of drains can be found elsewhere. (See "Principles of abdominal wall closure", section on 'Drains' and "Traumatic gastrointestinal injury in the adult patient", section on 'Role of drains'.)

Postoperative strategies — Postoperative goals in ERAS protocols include prevention and relief of pain or nausea and vomiting and facilitation of early nutrition and mobilization.

Pain management — Optimal perioperative pain management enhances recovery after colorectal surgery by facilitating postoperative ambulation and rehabilitation. Procedure-specific multimodal analgesia that minimizes opioid use is ideal [54,55].

●For patients undergoing laparoscopic colorectal procedures, we use nonopioid analgesics (eg, acetaminophen and a nonsteroidal anti-inflammatory drug [NSAID] or cyclooxygenase [COX]-2 specific inhibitor) in combination with local anesthetic infiltration at the portal sites [56].

In a nonrandomized study of laparoscopic colorectal surgery, local infiltration with a long-acting local anesthetic (liposomal bupivacaine) was associated with reduced opioid use, a shorter length of stay (mean three versus four days), and lower overall cost [57]. For cost reasons, others do not locally infiltrate liposomal bupivacaine during major abdominal surgery but reserve it for use in a transversus abdominis plane (TAP) block [58].

Acetaminophen, ibuprofen, and ketorolac are available in intravenous forms for patients who do not yet tolerate oral formulations. It remains controversial whether perioperative use of NSAIDs increases the risk of anastomotic leak. (See "Management of anastomotic complications of colorectal surgery", section on 'Controversial, inconclusive, or negative'.)

Also, we usually administer dexamethasone 8 to 10 mg for both analgesic and antiemetic prophylaxis. Thoracic epidural analgesia is no longer recommended after laparoscopic surgery, because it could potentially delay ambulation and hospital discharge without providing any additional benefit in pain control [56,59-61].

Infusions of lidocaine have been used to treat various forms of acute and chronic pain. The mechanism of action is through peripheral nociceptor sensitization and diminishing central neural excitability. In addition, lidocaine has potent anti-inflammatory properties that are more effective than traditional anti-inflammatory agents. A meta-analysis verified the efficacy of intravenous lidocaine for enhancing postoperative quality of recovery in patients receiving elective breast, thoracic, and laparoscopic surgery under general anesthesia [62]. However, the benefit was generally seen in the immediate 24 hours postoperatively, and there is some concern for major side effects [63].

●For patients undergoing open colorectal procedures, we typically use an interfascial plane block (eg, TAP block) or surgical site infiltration in combination with nonopioid analgesic agents [54]. In a small trial comparing TAP block with epidural in patients undergoing open and laparoscopic colorectal surgery, TAP block was associated with a 0.5 day reduction in hospital stay and a lower risk of urinary retention (15 versus 30 percent) but a higher risk of nausea and vomiting (33 versus 14 percent) [64]. The time to first flatus was comparable. (See "Approach to the management of acute pain in adults".)

Postoperative fluid management — Following major colorectal surgery, there is little consensus regarding optimal strategies for fluid management. Intravenous fluid administration should be discontinued as soon as the patient can tolerate oral liquids. Before oral intake is allowed, patients typically receive an infusion of a balanced salt solution (eg, Lactated Ringer) at 50 mL/hour, with boluses of 100 mL if necessary to treat hemodynamic instability and/or inadequate urine output (UO).

Although maintenance of a minimum hourly UO of 0.5 mL/kg is a common goal, limited data support this practice. In one randomized trial in 40 patients without significant risk factors for kidney injury, fluid was administered to maintain a minimum UO of either 0.2 or 0.5 mL/kg per hour during and after major abdominal surgery (from the time of anesthetic induction until the second postoperative day) [65]. While patients in the low-target UO group received less fluid than the high-target UO group (3170 versus 5490 mL), laboratory measurements of kidney function and other outcomes were not different. Thus, patients without risk factors for acute kidney injury may be managed with less postoperative fluid, but it is not known whether this practice can reduce postoperative complications or length of hospital stay.

The use of pharmacological diuresis following colon and rectal surgery remains a clinical conundrum because of a lack of data. In a small randomized trial of patients undergoing elective colorectal surgery, adding 10 mg of intravenous furosemide on postoperative day 1 and 2 to a standard ERAS program did not shorten length of stay and actually delayed return of bowel function [66]. Patients with chronic renal insufficiency, on chronic diuretic therapy, and those who experienced postoperative medical or surgical complications were excluded from the trial. This result suggests against administration of diuretics without a clinical indication; loop diuretics are more likely to deplete intravascular volume than remove extravascular fluids that have accumulated in the body (third-spacing). While chronic diuretic therapy should be restarted as soon as possible after surgery, others are best left to maintain their own euvolemia through auto-diuresis.

Diet — ERAS programs incorporate resumption of a diet within a few hours after surgery and can be supplemented with high-calorie drinks to minimize the negative protein balance after surgery. This is in contrast to the traditional approach where oral feedings were withheld until signs of bowel activity (eg, bowel sounds, flatus, bowel movement) were evident. In one study, the presence of bowel sounds, flatus, or bowel movement after major abdominal surgery was not predictive of tolerance of oral intake [67]. Details regarding postoperative nutritional support are discussed separately. (See "Overview of perioperative nutrition support".)

Early mobilization — Early mobilization is a key element of ERAS protocols for all postoperative patients capable of ambulation [68]. Early mobilization is essential to reducing the risk of postoperative pneumonia [69,70] and venous thromboembolism (see "Overview of the causes of venous thrombosis", section on 'Surgery'). Involving hospital resources such as physical and occupational therapists can help achieve the goal of early mobilization.

Avoidance of nasogastric tubes — Nasogastric tubes, once a mainstay of colon and rectal surgery, are associated with patient discomfort and a delay in time for oral intake and are not included in the ERAS protocols for most elective patients [71-73]. The authors do not use nasogastric tubes in elective colorectal surgery. The indications, management, and controversies associated with nasogastric tubes are discussed separately. (See "Inpatient placement and management of nasogastric and nasoenteric tubes in adults".)

Early urinary catheter removal — To aid with early mobilization, urinary catheters should be removed as early as possible, a process that also reduces the incidence of urinary tract infection after surgery. (See "Catheter-associated urinary tract infection in adults", section on 'Catheter management' and "Placement and management of urinary bladder catheters in adults", section on 'Catheter removal'.)

Predicting infective complication — C-reactive protein (CRP) is effective as an early predictor of infective complications after colorectal surgery. Postoperative day 3 CRP >150 mg/L or persistent elevation of CRP should increase suspicion of an infective complication. Conversely, CRP levels below this threshold are highly predictive of an uncomplicated recovery and are commonly used in ERAS protocols to guide discharge [74,75].

Early discharge — The goal of ERAS programs is an accelerated recovery and return to normal activity. Hospital stay (typically ≤5 days) is often used as a surrogate marker of recovery but is not the only focus of the protocol [76]. In comparison, the mean length of stay of a traditional practice is >5 to 9 days. In many ERAS programs, return of bowel function is no longer required before hospital discharge.

●In a multicenter European prospective nonrandomized study of over 3000 patients undergoing elective colorectal surgery, 9 percent were discharged before the return of bowel function [77]. Such patients did not have higher readmission or complication rates compared with patients who were discharged after return of bowel function, and the median hospital stay was shorter (5 [interquartile range 4 to 7] versus 7 [6 to 8] days).

●In a small trial (recoverMI) of 30 patients who underwent minimally invasive colectomy, patients who were discharged on postoperative day 1 with or without evidence of bowel function and a televideo conference on postoperative day 2 had shorter length of stay (28 versus 51 hours) and no worse adverse events or quality of life scores than those who received standard care [78].

As enhanced recovery programs continued to evolve, the length of hospitalization following elective minimally invasive colorectal surgery has continued to decline. Early experience with same-day discharge (SDD) protocols for elective, minimally invasive colorectal surgery suggests that such practice is feasible and safe [79]. SDD may be planned for healthy adults undergoing elective, minimally invasive colorectal resection without intraoperative complications or prolonged operative time [80-83]. Off-midline extraction of the specimen is preferred. The patient should also be cognitively and functionally independent and possesses good family support. To be successful, any SDD protocol must be able to assess readiness for discharge before return of gastrointestinal function, effect adequate pain control without intravenous medications, and establish a remote platform for postdischarge monitoring [84].

OUTCOMES — Data from observational studies and randomized trials show that enhanced recovery after surgery (ERAS) protocols are associated with reduced hospital length of stay (LOS) and morbidity, faster recovery, comparable or reduced readmission rate, and cost savings compared with traditional care in both older and young adults [3,14,85-92].

Mortality — The implantation of an ERAS protocol at five academic and community hospital within a single health system was associated with reduced 30 day, one-year, and two-year mortalities across eight surgical specialties [93].

Length of stay and morbidity — Contemporary series of colorectal surgery using ERAS protocols report hospital LOS ranging from three to five days [89,94-100]. In a 2014 systematic review and meta-analysis of 16 randomized trials of elective colorectal surgery, those managed with versus without an ERAS program had a significantly reduced LOS (weighed mean difference -2.28 days; 95% CI -3.09 to -1.47 days) and reduced overall morbidity (relative ratio [RR] 0.60, 95% CI 0.46-0.76) and nonsurgical complications (RR 0.40, 95% CI 0.27-0.61) but not a higher readmission rate [101]. A 2014 meta-analysis of 38 trials across all surgical specialities, including but not limited to colorectal surgery, reached a very similar conclusion that ERAS reduced both complications and LOS [102].

In-hospital morbidity rates may be lower secondary to the shorter LOS. Further prospective trials are needed to assess 30-day morbidities. However, in a 2017 meta-analysis of randomized trials of abdominal or pelvic surgery utilizing ERAS protocols, a subgroup analysis of colorectal surgery trials demonstrated a significant reduction in the rates of health-care-associated lung, urinary tract, and surgical site infections [103].

In a multicenter observational study by the Virginia Surgical Quality Collaborative involving 2438 consecutive colectomies, LOS was reduced (five versus four days for open colectomy; four to three days for laparoscopic colectomy) and total complication rate was similar or reduced (23 versus 22 percent for open colectomy; 16 versus 9 percent for laparoscopic colectomy) after ERAS implementation [104].

In a single-center trial of 63 patients undergoing minimally invasive colorectal surgery with a standardized ERAS protocol, the median 30 day total LOS (index admission plus any readmission) was only 51.5 (interquartile range [IQR] 43.8 to 67) hours in the control group [78]. Adding the option of videoconferencing on postoperative day 2 after discharge on postoperative day 1 further reduced the LOS to 28.3 (IQR 23.7 to 43.6) hours without reducing patient satisfaction/quality of life. Four patients in the videoconferencing group and one patient in the control group required emergency room visit or readmission, but none for reasons related to accelerated discharge. If further validated, this could potentially open pathways to ambulatory short-stay (23-hour observation) minimally invasive colorectal surgery.

In a study of 39,482 patients undergoing elective colorectal surgery, 7751 (20 percent) had full ERAS adherence. Patients with full adherence to core ERAS components had lower rates of postoperative complications than those with only partial adherence [105].

Faster recovery — In addition to shorter hospital LOS and lower morbidity, several other favorable postoperative outcomes of "enhanced" or faster recovery have been attributed to ERAS protocols in observational studies:

●Reduced duration of an ileus [106].

●Preservation of lean body mass and exercise performance [107].

●Improved grip strength suggesting overall improvement in muscle function [95].

●Earlier resumption of normal activities, reduced need for daytime sleep, and no increased use of primary care services [108].

Readmission rates — Early discharge (LOS ≤5 days) is the goal of ERAS protocols, but the benefit of early discharge may be offset by a higher rate of hospital readmission [76,90,101,109,110]. Early studies suggested that patients managed with ERAS programs had an increased readmission rate compared with traditional practice [86,87]. However, a meta-analysis of six later randomized trials and prospective studies found that the rate of readmission was not significantly different after ERAS versus traditional recovery programs (RR 1.17, 95% CI 0.73-1.86) [90].

Whether early discharge is associated with higher readmission rates and the optimal discharge day to avoid hospital readmission have not been clearly established. As an example, in a retrospective review of the United States National Medicare (MEDPAR) database, which included 477,461 patients undergoing a colectomy, very early discharge (defined as median LOS ≤4 days [21.3 versus 15.7 percent]), but not early discharge (defined as median LOS ≤5 days [16.3 versus 15.7 percent]), was associated with higher readmission rates compared with usual practice [76].

Cost — For an ERAS protocol to be financially justified, the cost (eg, from a laparoscopic procedure) must be balanced with savings from a shorter hospital admission, with fewer readmissions and complications. Prospective trials to analyze the costs and benefits of ERAS programs are in progress, with initial data suggesting an overall cost benefit [111-115].

Older patients — Critics of ERAS protocols cite selection bias for younger and healthier patients; however, ERAS protocols for elective colorectal resection have been shown to benefit older adults as well as younger patients. In the study mentioned above that used the MEDPAR database, patients were older than 65 years and were effectively treated with use of an ERAS protocol [76]. A prospective study of 87 patients aged 70 years and older reported a mean hospital stay of 3.9 days, with most (90 percent) tolerating early postoperative feedings [116].

Urgent colorectal surgery — Most existing ERAS programs have been designed, validated, and implemented for elective colorectal surgery. One small study found that although the compliance rate was lower with urgent surgery, elements of an ERAS protocol designed for elective surgery were also applicable to urgent surgery [117].

QUALITY IMPROVEMENT INITIATIVES — In 2010, the Enhanced Recovery After Surgery (ERAS) Society was founded to identify and implement methods to reduce the discrepancies noted between actual surgical practice and best practice. The ERAS Society has developed multimodal enhanced recovery care pathways, an implementation program, and an interactive audit system. The model is available to participants as a quality improvement initiative, providing detailed reports and feedback to assist surgeons and institutions with enhanced recovery for their patients [118].

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

SUMMARY AND RECOMMENDATIONS — Enhanced recovery after surgery (ERAS) programs are evidence-based protocols designed to standardize medical care, improve outcomes, and lower health care costs.

●Definition – ERAS protocols for colorectal surgical patients were developed to reduce inpatient hospital costs through refinements in preoperative, intraoperative, and postoperative strategies. Organization and effectiveness of an ERAS protocol requires participation and commitment from a multidisciplinary team, including surgeons, anesthesiologists, nursing staff, social services, and hospital administration. (See 'Introduction' above.)

●Recommendation – We suggest the ERAS approach for patients undergoing elective colorectal operations (Grade 2B). (See 'Outcomes' above.)

●Elements of ERAS protocol – The elements of an ERAS protocol include (table 1):

•Preoperative pathway strategies (eg, medical risk evaluation, prehabilitation, patient education including stoma management, mechanical bowel preparation plus oral antibiotics, and appropriate fasting guidelines). (See 'Preoperative strategies' above.)

•Intraoperative pathway strategies (eg, selection of short-acting anesthetic agents, lung-protective ventilation, restrictive fluid therapy, temperature regulation, and laparoscopic surgery). (See 'Intraoperative strategies' above.)

•Postoperative pathway strategies (eg, multimodal analgesia with an emphasis on nonopioid pain management, appropriate fluid management, early oral feeding and mobilization, avoidance of nasogastric tubes, early removal of urinary catheter, and early discharge). (See 'Postoperative strategies' above.)

●Outcomes – Use of ERAS protocols is associated with reduced hospital length of stay and morbidity, faster recovery, comparable or reduced readmission rate, and cost savings compared with traditional care in both old and young patients. (See 'Outcomes' above.)