Background This is the first updated Enhanced Recovery After Surgery (ERAS) Society guideline presenting a consensus for optimal perioperative care in gynecologic/oncology surgery. Methods A database search of publications using Embase and PubMed was performed. Studies on each item within the ERAS gynecologic/oncology protocol were selected with emphasis on meta-analyses, randomized controlled trials, and large prospective cohort studies. These studies were then reviewed and graded according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. Results All recommendations on ERAS protocol items are based on best available evidence. The level of evidence for each item is presented accordingly. Conclusions The updated evidence base and recommendation for items within the ERAS gynecologic/oncology perioperative care pathway are presented by the ERAS® Society in this consensus review.

Enhanced recovery after surgery (ERAS) pathways have been shown to considerably reduce complications, length of stay and costs after most of surgical procedures by standardised application of best evidence-based perioperative care. The aim was to elaborate dedicated recommendations for cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC) in a two-part series of guidelines based on expert consensus. The present part I of the guidelines highlights preoperative and intraoperative management. The core group assembled a multidisciplinary panel of 24 experts involved in peritoneal surface malignancy surgery representing the fields of general surgery (n = 12), gynaecological surgery (n = 6), and anaesthesia (n = 6). Experts systematically reviewed and summarized the available evidence on 72 identified perioperative care items, following the GRADE (grading of recommendations, assessment, development, evaluation) system. Final consensus (defined as ≥50%, or ≥70% of weak/strong recommendations combined) was reached by a standardised 2-round Delphi process, regarding the strength of recommendations. Response rates were 100% for both Delphi rounds. Quality of evidence was evaluated high, moderate low and very low, for 15 (21%), 26 (36%), 29 (40%) and 2 items, respectively. Consensus was reached for 71/72(98.6%) items. Strong recommendations were defined for 37 items, No consensus could be reached regarding the preemptive use of fresh frozen plasma. The present ERAS recommendations for CRS±HIPEC are based on a standardised expert consensus process providing clinicians with valuable guidance. There is an urgent need to produce high quality studies for CRS±HIPEC and to prospectively evaluate recommendations in clinical practice.

E nhanced recovery after surgery (ERAS) is an evidencebased and multidisciplinary perioperative care pathway and a surgical quality improvement initiative, which has been shown to promote patient mobilization, reduce complication rates after surgery, decrease hospital length of stay and reduce costs, if carefully implemented. There is an increasing interest across Canada to implement enhanced recovery after surgery recommendations. 1 Several Canadian institutions have succeeded in implementing an official ERAS protocol. However, it can be challenging to start such a program 2 because it requires multidisciplinary effort and the buy-in of many stakeholders. Because the ERAS approach has been shown to decrease the stress of surgery 3 through its objective to maintain patients' normal physiology as far as possible, any patient undergoing surgery could benefit from the approach. "Enhanced recovery" started with the initial work of Henrik Kehlet, a Danish colorectal surgeon, who in the early 2000s began to challenge many of the traditional surgical practices that were not supported by high-level evidence. 4 The Enhanced Recovery After Surgery Society (www.erassociety.org), an international, multidisciplinary, not-for-profit organization comprising surgeons, anesthesiologists, nurses and allied health professionals, delivers the ERAS program, and has made recommendations and developed guidelines for colorectal surgeries, 3,5 gynecologic surgeries, 6,7 pancreaticoduodenectomy, 8 hepatectomy, 9 gastrectomy, 10 urologic surgery 11 and esophagectomy, 12 all of which have been implemented with good results. 13 The ERAS approach can be broken down into 3 main components: preoperative, intraoperative and postoperative (Box 1). However, enhanced recovery begins with optimizing a patient's physical status before surgery. Therefore, primary care physicians can support successful implementation of enhanced recovery and help to improve patient outcomes by offering preoperative education and counselling. It is also important to remember that ERAS is a multifaceted approach that should be used for all surgical patients; in other words, anyone receiving a surgical intervention should have an enhanced recovery. We review evidence (Box 2) that supports the elements of the ERAS approach and discuss requirements for and barriers to implementation of an ERAS protocol.

Enhanced Recovery After Surgery Society publishes guidelines on perioperative care, but these guidelines should be validated prospectively. To evaluate the association between compliance with Enhanced Recovery After Surgery Gynecologic/Oncology guideline elements and postoperative outcomes in an international cohort. The study comprised 2101 patients undergoing elective gynecologic/oncology surgery between January 2011 and November 2017 in 10 hospitals across Canada, the United States, and Europe. Patient demographics, surgical/anesthesia details, and Enhanced Recovery After Surgery protocol compliance elements (pre-, intra-, and postoperative phases) were entered into the Enhanced Recovery After Surgery Interactive Audit System. Surgical complexity was stratified according to the Aletti scoring system (low vs medium/high). The following covariates were accounted for in the analysis: age, body mass index, smoking status, presence of diabetes, American Society of Anesthesiologists class, International Federation of Gynecology and Obstetrics stage, preoperative chemotherapy, radiotherapy, operating time, surgical approach (open vs minimally invasive), intraoperative blood loss, hospital, and Enhanced Recovery After Surgery implementation status. The primary end points were primary hospital length of stay and complications. Negative binomial regression was used to model length of stay, and logistic regression to model complications, as a function of compliance score and covariates. Patient demographics included a median age 56 years, 35.5% obese, 15% smokers, and 26.7% American Society of Anesthesiologists Class III-IV. Final diagnosis was malignant in 49% of patients. Laparotomy was used in 75.9% of cases, and the remainder minimally invasive surgery. The majority of cases (86%) were of low complexity (Aletti score ≤3). In patients with ovarian cancer, 69.5% had a medium/high complexity surgery (Aletti score 4-11). Median length of stay was 2 days in the low- and 5 days in the medium/high-complexity group. Every unit increase in Enhanced Recovery After Surgery guideline score was associated with 8% (IRR, 0.92; 95% confidence interval, 0.90-0.95; P<.001) decrease in days in hospital among low-complexity, and 12% (IRR, 0.88; 95% confidence interval, 0.82-0.93; P<.001) decrease among patients with medium/high-complexity scores. For every unit increase in Enhanced Recovery After Surgery guideline score, the odds of total complications were estimated to be 12% lower (P<.05) among low-complexity patients. Audit of surgical practices demonstrates that improved compliance with Enhanced Recovery After Surgery Gynecologic/Oncology guidelines is associated with an improvement in clinical outcomes, including length of stay, highlighting the importance of Enhanced Recovery After Surgery implementation.