Pancreaticoduodenectomy (PD), one of the most complex and invasive abdominal surgeries, is associated with long length of stay (LOS) and high morbidity and mortality rates. Enhanced Recovery After Surgery (ERAS) is gaining popularity because it reduces surgical stress and promotes physiological stability through standardized perioperative care, thereby improving the recovery process and outcomes after surgery.

ERAS is a comprehensive approach to perioperative care that involves the collaboration of multiple departments. Within the ERAS program, components primarily implemented by the anesthesiology department include preoperative carbohydrate loading, maintenance of near-zero fluid balance, and multimodal analgesic management, such as midthoracic epidural block. However, they may be underutilized for several reasons, such as deviation from conventional methods (e.g., preoperative carbohydrate loading) or the highly demanding nature of the procedures, which require significant human resources, specialized equipment, and time (e.g., thoracic epidural or transverse abdominis block).

Several randomized trials involving patients undergoing PD have reported that the implementation of ERAS has provided high-level evidence on a safer and quicker recovery, with decreased morbidity rates and shorter LOS than traditional care. Furthermore, a recent study on colorectal surgery reported that the ERAS program may improve not only short-term but also long-term oncological outcomes. However, there is a paucity of research investigating the effects of ERAS on mortality after PD. Furthermore, the impact of anesthesiology-related components within the ERAS pathway has not been extensively studied.

A previously published randomized controlled trial from our institution showed that the outcomes after applying pre- and postoperative ERAS protocols without anesthesiology-related components (Surg-ERAS) were comparable to those of the conventional protocol. This study aimed to compare the short- and long-term mortality rates among patients undergoing PD by examining the same cohort from a previous study, including the conventional (Non-ERAS) and Surg-ERAS groups, in addition to anesthesia fully implementing ERAS programs (ANS-Surg-ERAS group). Moreover, LOS; inflammation parameters, such as neutrophil to lymphocyte ratio (NLR) and C-reactive protein to albumin ratio (CAR); morbidity rate, reoperation rate, and readmission rate were compared among the three groups.

• The inclusion cirteria: The participants for this study comprised patients who were enrolled in the previous trial and those who met the same recruitment criteria, except for the inclusion of the ERAS protocol.

  *the previous trial: Hwang DW, Kim HJ, Lee JH, Song KB, Kim MH, Lee SK, Choi KT, Jun IG, Bang JY, Kim SC: Effect of Enhanced Recovery After Surgery program on pancreaticoduodenectomy: a randomized controlled trial. Journal of Hepato-Biliary-Pancreatic Sciences 2019; 26:360-9

• The exclusion criteria were as follows: distant metastasis, recurred periampullary cancer, active or uncontrolled infectious disease, severe psychological or neurological disease, alcohol or drug addiction, overlapping with other clinical trials, pregnancy, uncontrolled cardiopulmonary disease, comorbidities that could affect the quality of life and nutritional status (e.g., liver cirrhosis and renal failure), a history of major abdominal surgery (e.g., gastric resection or colonic resection), the need for simultaneous adjacent organ resection (e.g., portal vein, superior mesenteric vein, transverse colon, and liver), and plan to perform minimally invasive PD.

The Department of Hepatobiliary and Pancreatic Surgery initiated the ERAS program without collaborating with the anesthesiology department. Data for 247 patients receiving conventional and Surg-ERAS were extracted from the previous trial from March 2015 to May 2017. Since then, emphasis on the multidisciplinary aspect of the ERAS program has increased, leading to the involvement of the Department of Anesthesiology. From the start of the ERAS collaboration in July 2018, clinical data, including protocol adherence and clinical outcomes, have been prospectively recorded. Subsequently, 355 patients were included and followed up for at least 2 years to assess the relationship between different ERAS bundles and mortality.

The dataset used and/or analyzed during the current study is available from the corresponding author upon reasonable request.