Initial experience with the enhanced recovery after surgery (ERAS) protocols in gynecologic surgery at an urban academic tertiary medical center

Introduction

The enhanced recovery after surgery (ERAS), which is also known as fast-track surgery, refers to multimodal interventions to reduce the length of hospital stay and complications through alleviating the surgical stress response that patients experience before, during and after surgical procedures (1). This concept of multimodal approach was first developed in Denmark by colorectal surgeons, and later embraced by other surgical disciplines such as orthopedics, thoracic surgery, urology and gynecology (2). Following the release of ERAS Society guidelines specific to gynecologic oncology (3-6), several studies have demonstrated substantial benefit of ERAS (7,8). Despite these efforts, the adoption of ERAS in gynecology on global level has been disappointingly low and some centers have shown minimal improvement in clinical outcomes after adopting ERAS (9,10).

Herein, we report our experience of adopting the ERAS protocols at an urban tertiary academic medical center, Samsung Medical Center, located in Seoul, South Korea. Our primary aim was to assess the development and early experience of ERAS protocols in gynecologic surgery within real clinical setting, with a focus on improving patient outcomes and experiences. We present this article in accordance with the STROBE reporting checklist (available at https://gs.amegroups.com/article/view/10.21037/gs-23-249/rc).

Methods

This was an observational prospective cohort study of patients undergoing various types of gynecologic surgery for both benign and malignant indications. The present institution employs five gynecologic attending surgeons. Two of the five surgeons introduced the ERAS protocols in October 2020 for their patient care. The other three withheld the implementation of the protocols and adhered to the previously established standard of care. We assessed the clinical outcomes and subjective views from the patients reflected by the pre-made questionnaire between the ERAS cohort vs. non-ERAS cohort. We also compared the outcomes of the ERAS cohort against the data from the patients who had received the identical surgical procedures from the same two ERAS surgeons prior to their protocol adoption (comparison between the ERAS cohort vs. non-ERAS historical cohort). The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the Institutional Review Board of Samsung Medical Center (No. 2023-11-058). Informed consent was obtained from all individual participants.

Patient selection and data collection

All patients who underwent major abdominal and laparoscopic gynecologic surgery between October 2020 and February 2021 were included. The patients who underwent surgery for vulvar cancer and for emergent conditions were excluded because evidence supporting the benefits of ERAS interventions have not been established in this specific group of patients. Data collected included patients’ demographics, co-morbidities (American Society of Anesthesiologists performance score), body mass index (BMI), surgical information, postoperative complications (classified as per Dindo-Clavien surgical complication grading), use of postoperative analgesic medications, and length of hospital stay.

The ERAS team

A core group of gynecologists, anesthesiologists, nurses and mid-level providers across the gynecologic cancer center were identified to participate in the implementation of ERAS. Selection was based on their understanding of ERAS principles, and their willingness and ability to participate in patient care. The team members undertook a consultation process during the protocol development to ensure that the clinical providers were in agreement with all components of the care. Regular communication provided opportunities for feedback and identification of barriers to implementation. Evidence-based interventions reported in the literature were evaluated with existing institutional experience for relevance in gynecologic surgery. Through discussions and consensus building, components of the gynecologic ERAS program were developed. A standardized order set was created within the electronic medical records (EMR) system to facilitate uniform delivery of care. Patient education aids were created, and a questionnaire consisting of 12 items was developed.

Description of intervention: ERAS protocols

Specific components of the ERAS program were developed after an extensive review of the current evidence from the literature (11). The components of the ERAS protocols are described in Table S1. Patient education regarding the perioperative process began with the decision to proceed with surgery. All patients attended a pre-admission consultation. After detailed medical history and clinical assessment, patients were provided with verbal and written information relevant to their diagnosis, proposed treatment and perioperative management. This step was to prepare the patient to take an active role in her recovery and set realistic expectations for postoperative care, including duration of stay and postoperative pain control. Patients were provided with a booklet that introduced all members of the perioperative care team and a day-by-day breakdown of what to expect during the hospital stay. Admission one day prior to surgery was made at 5 PM. Mechanical bowel preparation was avoided and preoperative fasting period for solid food was reduced to less than 6 hours before the surgery and clear oral fluids were allowed up until three hours preoperatively (Figure 1). Complex carbohydrate loading drinks were used as they have a short stomach transit period due to their relatively low osmolality. Carbohydrate drinks were given 12 hours prior to the surgery and up to three hours before going to the operating room, provided gastric emptying was not impaired. The intervals between each drink were determined according to the patients’ scheduled time of operations. An attempt was made to offer minimally-invasive surgery for the majority of cases. Intravenous antibiotics one hour prior to skin incision were administered in order to reduce infection risk. Naso-gastric tubes and abdominal drains were avoided wherever possible. There was no use of pre-medication to anesthesia. Anesthesiologists adopted a consistent protocol in intraoperative management and fluid balance. Postoperative pain management included regular use of acetaminophen and nonsteroidal anti-inflammatory drug (NSAID). Patients were encouraged to have an oral fluid intake and resume carbohydrate drinks 6 hours postoperatively, to facilitate return to normal diet. On the first postoperative day full blood count was checked and intravenous fluids, patient-controlled anesthesia (PCA) and urinary drainage were removed (unless indicated otherwise). The criteria for discharge in the ERAS group included normal or stable hemoglobin levels, tolerable pain with oral analgesia only, tolerance of solid food, being able to ambulate independently and willingness to go home. Where individual patient factors precluded a particular intervention (e.g., previous esophageal surgical history that might increase complication risk in early postoperative diet), the intervention was withheld.

Figure 1 Timeline of preoperative fasting and carbohydrate loading.

Patient survey questionnaire regarding their perioperative experience

All patients in our study were provided with a booklet explaining specific components of the ERAS protocols on admission. The booklet included a questionnaire with 12 items assessing patients’ subjective feelings in regards to specific metrics and their overall satisfaction with the perioperative experience. The items on the questionnaire were adopted from the Patient Reported Outcomes Measurement Information System (PROMIS) (12,13). The original questionnaire was validated by its authors. For example, the patients were asked on a Likert scale how thirsty they felt, how hungry they felt, and how painful they felt perioperatively. They were also asked when they first left their hospital room for ambulation, how many times they chewed gum after surgery, and how many cups of coffee they drank.

Historical comparison group

To correct potential confounding factors, each patient in the ERAS cohort was matched (1:1 ratio) to a patient in the historical non-ERAS cohort using exact matching based on age (within a 5-year age range), surgery type, final diagnosis and disease stage for malignancies [by the FIGO (International Federation of Gynecology and Obstetrics) stage system].

Statistical analysis

Descriptive statistics such as means, standard deviations, medians, and ranges were used as appropriate. The Pearson’s Chi-squared test and Fisher’s exact test were used to examine associations between the groups for categorical variables. The Wilcoxon rank-sum test and Student’s t-test were used for continuous variables. A P value lower than 0.05 was considered statistically significant. Data were analyzed with SPSS 22.0 software (SPSS, Inc., Chicago, IL, USA).

Results

Baseline characteristics and operative information

From October 1, 2020 to February 28, 2021, a total of 244 patients were identified who underwent surgical procedures at our institution. Among them, 122 patients received perioperative care with the ERAS components while the other 122 patients received the conventional perioperative care. The baseline characteristics of the patients such as age, BMI, medical comorbidity, history of previous surgery, and indication for surgery were similar between the two groups (Table 1). Additionally, the operative information, including the types of surgical approach (laparotomy vs. laparoscopy), use of robot-assisted surgery and the extent of surgical procedures showed no significant differences between the two groups. There was no significant difference between the two groups in terms of hemoglobin drop on postoperative day 1 and length of hospital stay (Table 2).

Perioperative patients experiences

In general, the patients in the ERAS cohort felt less hunger and thirst before and after surgery, regardless of whether they had laparotomic or laparoscopic procedures (Table 3). Another notable finding was that the subjective feelings of pain were significantly lower in the ERAS cohort compared to the non-ERAS cohort. For laparotomic surgery, the mean pain score for ERAS cohort was 6.2±2.9, while it was 7.9±2.1 for non-ERAS cohort (P=0.029). Similar findings were observed for laparoscopic surgery (3.9±2.1 for ERAS cohort vs. 5.5±2.3 for non-ERAS cohort, P<0.001). The patients’ answers in regards to nausea, and abdominal bloatedness did not differ between the two groups. Nausea, abdominal bloating, and the first gas out time did not differ between the two groups. The ambulation initiation time was also similar, even though the ERAS cohort had been instructed about the importance of early and active ambulation preoperatively. However, the patients in the ERAS group were more satisfied with their fasting time.

Use of postoperative analgesic agents

One of the key elements of the ERAS protocols is postoperative pain management. Among multiple acceptable regimens, we utilized a combination of acetaminophen and NSAID. The patients in the ERAS cohort received 30 mg of intravenous NSAID (ketorolac) immediately after surgery, followed by 1 g of intravenous acetaminophen 4 hours later. The medications were alternated every 4 hours until the patients resumed their diet, thereby being able to take oral analgesic medications. In contrast, the conventional pain management method in our institution included ketorolac, meperidine, or morphine based on the physician’s discretion and patient request (most physicians in the present institution start with NSAID for initial pain management unless contraindicated). This change of postoperative pain management significantly reduced the use of meperidine (Table 4).

ERAS patients, especially those who underwent laparotomy, received fewer vials of meperidine during the first two postoperative days (0.7±0.3 vials for ERAS group vs. 1.7±1.1 vials for non-ERAS group, P<0.001). The number of vials of NSAID did not differ, but the number of vials of acetaminophen was higher in the ERAS cohort, perhaps due to the already established method of pain management using NSAID.

Results from matched analysis with pre-ERAS historical cohort

A matched analysis on key elements of the ERAS protocols between the ERAS cohort against the non-ERAS historical cohort was performed (Tables 5,6). The use of meperidine was significantly lower in the ERAS cohort compared to the non-ERAS historical cohort. Furthermore, the length of hospital stay for those who underwent laparotomy was significantly reduced after implementing the ERAS protocols (2.8±1.1 days for the ERAS cohort vs. 3.5±1.4 days for the non-ERAS historical cohort, P=0.014).

Discussion

The present study represents that the development and implementation of an ERAS in gynecology at an urban tertiary academic medical center is feasible. We were able to demonstrate a reduction in opioid use for postoperative pain control, greater amount of postoperative ambulation, and a higher satisfaction of the patients in regards to perioperative fasting time. Overall, we did observe benefits of the ERAS protocols on a number of key elements without compromising the safety measures of the conventional perioperative care. However, unlike previous studies, we did not observe earlier return of bowel movement and earlier initiation of ward ambulation. Shorter hospital stay was only observed when comparing patients who underwent laparotomic surgeries by the same surgeon before and after the implementation of ERAS through matched analysis.

The ERAS principles incorporate multiple interventions in patients’ care from preoperative assessment to postoperative discharge. This makes it difficult to identify a single or most significant intervention into the success or failure of the program.

Perhaps the greatest change we made by implementing the ERAS protocols in our patient care was the shortening of fasting time and the administration of carbohydrate drinks prior to surgery. There is a substantial amount of data which suggests early feeding decreases risks of infectious complications and duration of hospital stay without increasing rates of ileus or pulmonary complications (14-17). Thus, the advancement to a regular diet is recommended within 24 hours of surgery for gynecologic surgery patients (4). In our practice, patients were allowed to have liquids immediately after surgery and were advanced to a regular diet as tolerated within the first 24 hours. Additionally, the patients were encouraged to chew gum postoperatively based on the evidence that this may accelerate the return of bowel function (18,19). Preoperative administration of oral carbohydrate has also shown a significantly reduced postoperative hospital stay, and a trend towards earlier return of bowel movement when compared with fasting or supplementary water (20). Unfortunately, the present study did not observe earlier recovery of bowel movement. The time of initial flatulence or gas out after surgery did not differ between the ERAS cohort and non-ERAS cohort. This may be partly due to the short period of postoperative hospital stay. The duration of postoperative care at the hospital may not be sufficient to detect the potential benefits of shortened fasting time and earlier return to diet. Indeed, only 59% of the ERAS cohort and 40% of the non-ERAS cohort were able to catch their first flatulence during the hospitalization and answered it on the survey. Others were discharged before the first flatulence occurred. Therefore, it is recommended for future studies to assess the benefits of short fasting period with more objective outcome measures.

Given the recommendations for early feeding, most patients did not require intravenous hydration for longer than 24 hours postoperatively. In addition to intravenous poles limiting patient mobility (21), fluid overload can result in pulmonary edema, increased risk of ileus, and a prolonged duration of stay (22). Our ERAS patients were started on dextrose sodium potassium chloride solution in the immediate postoperative period. Intravenous fluids were discontinued early on the morning of postoperative day 1 in all patients who were tolerating liquids orally. Earlier discontinuation of intravenous fluids, thereby accommodating patient mobility, may have led to the greater amount of ward ambulation seen in the ERAS cohort. The patients who received laparoscopic surgery in the ERAS group performed almost twice as much exercise than the non-ERAS cohort patients both on the same day of their surgery and on the first postoperative day. The amount of exercise for those who received laparotomic surgery was not significantly different between the ERAS and non-ERAS cohorts immediately after surgery, but the patients in the ERAS cohort reported greater amount of ambulation on postoperative day 2.

A previous study reported that the combination of acetaminophen and NSAID is particularly effective and has a great effect than either agent given alone (23). In our practice, patients with acceptable renal and hepatic function were given scheduled NSAID and acetaminophen beginning immediately after surgery. These intravenous administrations of analgesic medication were subsequently transitioned to oral ibuprofen 500 mg every 12 hours. Patients who were unable to receive NSAID for any reason were given tramadol 50 to 100 mg every 8 hours. The routine administration of these agents resulted in less use of meperidine and less subjective feelings of pain as reported on the patient questionnaire. The effectiveness of multimodal opioid-sparing analgesia was attenuated two days after surgery and the pain scores reported by the patients became comparable between the ERAS and non-ERAS groups.

There have been a number of incidences where the execution of the ERAS protocols were faced with problems. Such incidences were due to unexpectedly high complexity of surgery, errors in inter-department communications and patient refusal (Table S2). In some cases, surgical procedures that necessitated postoperative intensive care unit (ICU) admission sometimes prevented the complete adherence to ERAS protocols. The application of ERAS protocols to ovarian cancer patients, in particular, poses unique difficulties. The majority of these patients are diagnosed with advanced-stage disease, requiring complex surgical interventions often involving on-the-spot decision-making. This unpredictability makes it difficult to plan optimal postoperative management in advance. Factors such as extensive and unpredictable surgical procedures, which may include multivisceral resections, and the high risk of postoperative complications, which can lead to poor nutritional status, make implementing ERAS protocols in ovarian cancer patients challenging. Furthermore, it is worth noting that much of the evidence supporting ERAS guidelines has been derived from observational studies in other surgical disciplines, primarily colorectal surgeries. The medical conditions of ovarian cancer patients can differ significantly from those of colorectal cancer patients, underscoring the importance of scientific evaluation specific to ovarian malignancies. While there is a shortage of clinical trials on ERAS protocols in ovarian cancer patients, existing evidence indicates improved perioperative outcomes (24). Whether these enhanced perioperative outcomes translate into better survival remains an open question, but the current evidence consistently shows the benefits of ERAS protocols. Establishing strong scientific evidence for ERAS protocols in ovarian cancer patients is crucial, as is fostering a collaborative team environment for a multidisciplinary approach and conducting ongoing audits to improve patient care (25). Errors in communications between the surgical team and nursing department once resulted in inappropriate administration of carbohydrate drinks which could not secure three hours of fasting time preoperatively. Good communication and close teamwork with preoperative assessment, anesthesiologists, clinical nurses, and physicians are key factors for the successful implementation of ERAS. In our study, fasting time adherence emerged as a significant barrier, sometimes necessitating surgery postponement; however, recent research suggests that consuming clear fluid within two hours before surgery may pose a manageable challenge, as it falls within the clinically accepted risk margin for regurgitation and aspiration (26).

There are a number of limitations exist in the present study. First, the subjective nature of questionnaire limits its objective interpretation. Second, the comparison between the ERAS cohort and non-ERAS cohort may have bias arising from the fact that the two groups had different attending surgeons. In order to minimize this, we performed matched analysis between the ERAS cohort against the non-ERAS historical cohort. However, this may not have completely eliminated the potential bias. Although numerous data are available that support the benefits of each ERAS protocol component, only a few prospective randomized trials have been conducted so far that assessed the benefits of the bundled ERAS protocols (27). Furthermore, given the positive evidence of the ERAS protocols already established by previous studies, it may not be ethically feasible to perform randomized clinical trials in this setting. In order to compensate this limitation, future studies with rigorous statistical methodologies are recommended with various patient populations.

We observed a high adherence to the program guidelines by the patients despite the fact that the ERAS protocols were relatively new to the patients. The establishment of uniform order sets in our EMR system has also enabled us to run the protocols without major obstacles. Overall, the implementation of ERAS protocols in gynecologic surgery has been successful. It has been well accepted by the healthcare providers and the patients.

Conclusions

Our study demonstrated the safety, clinical feasibility and benefits of the ERAS protocols for patients undergoing gynecologic surgeries for both benign and malignant indications. The advantages of ERAS were more evident in laparotomic surgeries compared to laparoscopic surgeries, suggesting variations based on surgical approach. Customization according to the surgical approach and close teamwork for a multidisciplinary approach are key for improved patient care. Further research is needed on the benefits of shorter fasting periods in diverse patient populations.

Acknowledgments

The abstract of this manuscript has a history of being presented as a E-poster in the past: (I) Noh J, Choi CH, Kim T, et al. EPV263/#470 Initial experience with the enhanced recovery after surgery (ERAS) protocol in gynecology at a tertiary academic medical center. Int J Gynecol Cancer 2021;31:A133. (II) Kim WJ, Noh JJ, Lee YY, et al. Poster (M02) Initial experience with the enhanced recovery after surgery (ERAS) protocol in gynecology at a tertiary academic medical center. ASGO (2021) https://doi.org/10.3802/jgo.2021.32.S1.M02.

Funding: This work was supported by the National Research Foundation of Korea (NRFK) grant funded by the Korean government (MSIT) (No. 2019R1F1A1063567), and Research and Business Development Program through the Korea Institute for Advancement of Technology (KIAT) funded by the Ministry of Trade, Industry and Energy (MOTIE) (No. P0014051).

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://gs.amegroups.com/article/view/10.21037/gs-23-249/rc

Data Sharing Statement: Available at https://gs.amegroups.com/article/view/10.21037/gs-23-249/dss

Peer Review File: Available at https://gs.amegroups.com/article/view/10.21037/gs-23-249/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gs.amegroups.com/article/view/10.21037/gs-23-249/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by Institutional Review Board of Samsung Medical Center (No. 2023-11-058). Informed consent was obtained from all individual participants.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Kehlet H. Fast-track colorectal surgery. Lancet 2008;371:791-3. [Crossref] [PubMed]
2. Gravante G, Elmussareh M. Enhanced recovery for colorectal surgery: Practical hints, results and future challenges. World J Gastrointest Surg 2012;4:190-8. [Crossref] [PubMed]
3. Nelson G, Altman AD, Nick A, et al. Guidelines for pre- and intra-operative care in gynecologic/oncology surgery: Enhanced Recovery After Surgery (ERAS®) Society recommendations--Part I. Gynecol Oncol 2016;140:313-22. [Crossref] [PubMed]
4. Nelson G, Altman AD, Nick A, et al. Guidelines for postoperative care in gynecologic/oncology surgery: Enhanced Recovery After Surgery (ERAS®) Society recommendations--Part II. Gynecol Oncol 2016;140:323-32. [Crossref] [PubMed]
5. Nelson G, Bakkum-Gamez J, Kalogera E, et al. Guidelines for perioperative care in gynecologic/oncology: Enhanced Recovery After Surgery (ERAS) Society recommendations-2019 update. Int J Gynecol Cancer 2019;29:651-68. [Crossref] [PubMed]
6. Nelson G, Fotopoulou C, Taylor J, et al. Enhanced recovery after surgery (ERAS®) society guidelines for gynecologic oncology: Addressing implementation challenges - 2023 update. Gynecol Oncol 2023;173:58-67. [Crossref] [PubMed]
7. Marx C, Rasmussen T, Jakobsen DH, et al. The effect of accelerated rehabilitation on recovery after surgery for ovarian malignancy. Acta Obstet Gynecol Scand 2006;85:488-92. [Crossref] [PubMed]
8. Gerardi MA, Santillan A, Meisner B, et al. A clinical pathway for patients undergoing primary cytoreductive surgery with rectosigmoid colectomy for advanced ovarian and primary peritoneal cancers. Gynecol Oncol 2008;108:282-6. [Crossref] [PubMed]
9. Bhandoria GP, Bhandarkar P, Ahuja V, et al. Enhanced Recovery After Surgery (ERAS) in gynecologic oncology: an international survey of peri-operative practice. Int J Gynecol Cancer 2020;30:1471-8. [Crossref] [PubMed]
10. Dickson EL, Stockwell E, Geller MA, et al. Enhanced Recovery Program and Length of Stay After Laparotomy on a Gynecologic Oncology Service: A Randomized Controlled Trial. Obstet Gynecol 2017;129:355-62. [Crossref] [PubMed]
11. Noh JJ, Kim MS, Lee YY. The implementation of enhanced recovery after surgery protocols in ovarian malignancy surgery. Gland Surg 2021;10:1182-94. [Crossref] [PubMed]
12. Garcia SF, Cella D, Clauser SB, et al. Standardizing patient-reported outcomes assessment in cancer clinical trials: a patient-reported outcomes measurement information system initiative. J Clin Oncol 2007;25:5106-12. [Crossref] [PubMed]
13. Cella D, Riley W, Stone A, et al. The Patient-Reported Outcomes Measurement Information System (PROMIS) developed and tested its first wave of adult self-reported health outcome item banks: 2005-2008. J Clin Epidemiol 2010;63:1179-94. [Crossref] [PubMed]
14. Fanning J, Valea FA. Perioperative bowel management for gynecologic surgery. Am J Obstet Gynecol 2011;205:309-14. [Crossref] [PubMed]
15. Charoenkwan K, Matovinovic E. Early versus delayed oral fluids and food for reducing complications after major abdominal gynaecologic surgery. Cochrane Database Syst Rev 2014;2014:CD004508. [Crossref] [PubMed]
16. Pearl ML, Valea FA, Fischer M, et al. A randomized controlled trial of early postoperative feeding in gynecologic oncology patients undergoing intra-abdominal surgery. Obstet Gynecol 1998;92:94-7. [Crossref] [PubMed]
17. Schilder JM, Hurteau JA, Look KY, et al. A prospective controlled trial of early postoperative oral intake following major abdominal gynecologic surgery. Gynecol Oncol 1997;67:235-40. [Crossref] [PubMed]
18. Pereira Gomes Morais E, Riera R, Porfírio GJ, et al. Chewing gum for enhancing early recovery of bowel function after caesarean section. Cochrane Database Syst Rev 2016;10:CD011562. [Crossref] [PubMed]
19. Mei B, Wang W, Cui F, et al. Chewing Gum for Intestinal Function Recovery after Colorectal Cancer Surgery: A Systematic Review and Meta-Analysis. Gastroenterol Res Pract 2017;2017:3087904. [Crossref] [PubMed]
20. Noblett SE, Watson DS, Huong H, et al. Pre-operative oral carbohydrate loading in colorectal surgery: a randomized controlled trial. Colorectal Dis 2006;8:563-9. [Crossref] [PubMed]
21. Chase DM, Lopez S, Nguyen C, et al. A clinical pathway for postoperative management and early patient discharge: does it work in gynecologic oncology? Am J Obstet Gynecol 2008;199:541.e1-7. [Crossref] [PubMed]
22. Kalogera E, Dowdy SC. Enhanced Recovery Pathway in Gynecologic Surgery: Improving Outcomes Through Evidence-Based Medicine. Obstet Gynecol Clin North Am 2016;43:551-73. [Crossref] [PubMed]
23. Ong CK, Seymour RA, Lirk P, et al. Combining paracetamol (acetaminophen) with nonsteroidal antiinflammatory drugs: a qualitative systematic review of analgesic efficacy for acute postoperative pain. Anesth Analg 2010;110:1170-9. [Crossref] [PubMed]
24. Sánchez-Iglesias JL, Carbonell-Socias M, Pérez-Benavente MA, et al. PROFAST: A randomised trial implementing enhanced recovery after surgery for highcomplexity advanced ovarian cancer surgery. Eur J Cancer 2020;136:149-58. [Crossref] [PubMed]
25. Noh JJ, Lee YY. Where is ERAS in the management of advanced ovarian cancer?: between myths and truths. J Gynecol Oncol 2022;33:e79. [Crossref] [PubMed]
26. Marsman M, Kappen TH, Vernooij LM, et al. Association of a Liberal Fasting Policy of Clear Fluids Before Surgery With Fasting Duration and Patient Well-being and Safety. JAMA Surg 2023;158:254-63. [Crossref] [PubMed]
27. Ferrari F, Forte S, Odicino F. Validation of an enhanced recovery after surgery protocol in gynecologic surgery: an Italian randomized study, a response. Am J Obstet Gynecol 2021;224:336-7. [Crossref] [PubMed]