Safety and feasibility of single-incision laparoscopic distal gastrectomy in overweight and obese gastric cancer patients: a propensity score-matched analysis.

BACKGROUND: The technical challenges and safety concerns of single-incision laparoscopic gastrectomy for overweight and obese gastric cancer patients remain unclear. This study aimed to evaluate the safety and feasibility of single-incision laparoscopic distal gastrectomy (SIDG) compared to multiport laparoscopic distal gastrectomy (MLDG) in overweight and obese gastric cancer patients. METHODS: This study retrospectively analyzed overweight and obese patients (body mass index ≥ 25 kg/m2) and pathologic stage T1 primary gastric adenocarcinoma treated with either SIDG or MLDG. The SIDG and MLDG groups were propensity score matched at a 1:2 ratio using age, sex, height, body weight, American Society of Anesthesiologists classification, year of surgery, pathologic N stage, and anastomosis method as covariates. RESULTS: After 1:2 matching, the study included patients who underwent SIDG (n = 179) and MLDG (n = 358). No significant difference in the number of retrieved lymph nodes was found between the SIDG and MLDG groups (52.8 ± 19.3 vs. 53.9 ± 21.0, P = 0.56). Operation times were significantly shorter in the SIDG group (170.8 ± 60.0 min vs. 186.1 ± 52.6 min, P = 0.004). The postoperative hospital length of stay was comparable between the 2 groups (SIDG: 5.9 ± 3.4 days vs. MLDG: 6.3 ± 5.1 days, P = 0.23), as was postoperative complication rate (SIDG: 13.4% vs. MLDG: 12.8%, P = 0.89). CONCLUSIONS: SIDG was shown to be as safe and feasible as MLDG for overweight and obese gastric cancer patients, with comparable early postoperative complication rates without compromising operation time compared to MLDG.

Single-port intragastric wedge resection using the tunnel method: a novel surgical approach for treating endophytic gastric subepithelial tumors.

BACKGROUND: Intragastric wedge resection is an effective method for treating endophytic gastric subepithelial tumors (SETs). However, retracting the stomach wall to the umbilicus is difficult in certain patients. In response, we developed a novel surgical technique for single-port intragastric wedge resection, which we termed the "tunnel method." METHODS: A transumbilical incision is made, and a wound retractor is applied. After diagnostic laparoscopy, a gastrostomy is made on the greater curvature, lower body. Another small wound retractor is inserted into the gastrostomy, and extracted through the transumbilical incision, creating a tunnel from the gastrostomy site to the umbilicus. Articulating laparoscopic instruments are inserted via the tunnel, and intragastric wedge resection is performed. We collected and analyzed the clinicopathologic and operative data of patients who underwent intragastric wedge resection via the tunnel method. RESULTS: Twenty-seven patients who underwent single-port intragastric wedge resection via the tunnel method in a single tertiary referral hospital were included in this study. The mean age of the patients was 54.6 ± 11.4 years, body mass index was 26.5 ± 3.4 kg/m2. Twenty-four (88.9%) patients had tumors located in the upper third of the stomach. The average operative time was 65.0 ± 24.2 min. None of the patients experienced Clavien-Dindo grade IIIa or higher postoperative complications. The average postoperative hospital stay length was 2.5 ± 0.8 days. Thirteen gastrointestinal stromal tumors, nine leiomyomas, and one neuroendocrine carcinoma, schwannoma, lipoma, spindle cell proliferative lesion, and fibrotic lesion were pathologically diagnosed. The average tumor size was 2.6 ± 1.3 cm. All cases had negative resection margins. CONCLUSIONS: Single-port intragastric wedge resection by the tunnel method is a feasible and safe approach for treating endophytic gastric SETs.

Hyperthermic pressurized intraperitoneal aerosol drug delivery system in a large animal model: a feasibility and safety study.

BACKGROUND: We developed a novel drug delivery system called hyperthermic pressurized intraperitoneal aerosol chemotherapy (HPIPAC) that hybridized Hyperthermic intraperitoneal chemotherapy (HIPEC) and pressurized intraperitoneal aerosol chemotherapy (PIPAC). The present study aims to assess the feasibility and safety of HPIPAC system in a large animal survival model. METHODS: Eleven pigs (eight non-survival models and three survival models) were used in the experiment. The heat module in the HPIPAC controller circulates hyperthermic CO2 in a closed-loop circuit and creates gas-based dry intraperitoneal hyperthermia. Three 12 mm trocars were placed on the abdomen. The afferent CO2 tube wound with heat generating coil was inserted into a trocar, and the efferent tube was inserted into another trocar. Heated CO2 was insufflated and circulated in a closed circuit until the intra-abdominal and peritoneal surface temperature reached 42 °C. 100 ml of 5% dextrose in water was nebulized for 5 min and the closed-loop circulation was resumed for 60 min at 42 °C. Tissue biopsies were taken from several sites from the pigs in the survival model. RESULTS: The average change in core temperature of the pigs was 2.5 ± 0.08 °C. All three pigs displayed no signs of distress, and their vital signs remained stable, with no changes in their diet. In autopsy, inflammatory and fibrotic responses at the biopsy sites were observed without serious pathologic findings. CONCLUSIONS: We successfully proved the feasibility and safety of our novel HPIPAC system in an in-vivo swine survival model.

Comparison of perioperative outcomes between bipolar sealing, ultrasonic shears and a hybrid device during laparoscopic gastrectomy for early gastric cancer: a prospective, multicenter, randomized study.

BACKGROUND: Although EBDs are essential for minimally invasive surgery, well-established prospective randomized studies comparing EBDs are scarce. This study aimed to compare the intraoperative inflammatory response and short-term surgical outcomes among different energy-based devices (EBDs) in laparoscopic distal gastrectomy (LDG). METHODS: Patients with clinical stage I gastric cancer scheduled for LDG at two different medical centers were prospectively randomized into three groups: ultrasonic shears (US), advanced bipolar (BP) and ultrasonic-bipolar hybrid (HB). The C-reactive protein (CRP) level, operation time, intraoperative blood loss (IBL), laboratory tests, cytokines (interleukin (IL)-6 and IL-10), hospital stay, and complication rate were analyzed. A novel semiquantitative measurement method using indocyanine green (ICG) and a near-infrared camera measured the amount of lymphatic leakage. RESULTS: The primary endpoint, the CRP level, was significantly lower in the BP (n = 60) group than in the US (n = 57) or HB (n = 57) group [9.03 ± 5.55 vs. 11.12 ± 5.02 vs. 12.67 ± 6.14, p = 0.001, on postoperative day (POD) 2 and 7.48 vs. 9.62 vs. 9.48, p = 0.026, on POD 4]. IBL was significantly lower in BP than in US or HB (26.3 ± 25.3 vs. 43.7 ± 42.0 vs. 34.9 ± 37.0, p = 0.032). Jackson-Pratt drainage triglycerides were significantly lower in BP than in US (53.6 ± 33.7 vs. 84.2 ± 59.0, p = 0.11; HB: 71.3 ± 51.4). ICG fluorescence intensity, operation time, laboratory results, cytokines, hospital stay, and complication rate were not significantly different among the 3 groups. CONCLUSION: BP showed a lower postoperative CRP level and less IBL than US and HB, suggesting less collateral thermal damage and better sealing function. Surgeons may consider this when selecting EBDs for laparoscopic surgery.

Postoperative pain and quality of life after single-incision distal gastrectomy versus multiport laparoscopic distal gastrectomy for early gastric cancer - a randomized controlled trial.

BACKGROUND: Although it has been more than ten years since its first introduction, single-incision distal gastrectomy (SIDG) still lacks solid evidence and there are also no reports on patient quality of life (QOL). This study evaluates the postoperative outcomes and patient QOL of SIDG compared to multiport laparoscopic distal gastrectomy (MLDG). METHODS: This study was designed as a prospective phase II randomized controlled study. Patients diagnosed with early gastric cancer in the distal 2/3rd of the stomach were randomized to either multiport or single-port group. Primary endpoint was pain using the visual analogue scale on postoperative day (POD) 1. Other outcomes include operative data, complications, and patient QOL using the EORTC C30 and STO22 modules. RESULTS: A total of 43 patients in the SIDG group and 40 patients in the MLDG group were enrolled from September 2017 to February 2020. Mean operation time was 154.3 ± 53.3 min in the MLDG group and 148.9 ± 50.1 min in the SIDG group (p = 0.631). There was no difference in POD1 pain scores between the two groups (MLDG = 4.0 ± 1.3, SIDG = 4.3 ± 1.3, p = 0.372). Mean hospital stay was 5.5 (range 4-12) days in the MLDG group and 5 (range 4-17) days in the SIDG group (p = 0.993). There was no statistical significance in postoperative QOL scores. CONCLUSION: Unlike previous reports, there was no difference in POD1 pain scores between SIDG and MLDG. Nevertheless, SIDG did not increase short-term morbidity compared to MLDG and had similar outcomes in QOL.

Feasibility and safety of pure single-incision laparoscopic total and proximal gastrectomy for early gastric cancer: propensity score-matched comparison to multiport totally laparoscopic approach.

BACKGROUND: There have been few studies regarding the feasibility and safety of pure single-incision laparoscopic total gastrectomy (SITG) or proximal gastrectomy (SIPG) for early gastric cancer (EGC). The purpose of this study was to analyze the surgical outcome of all consecutive SITG or SIPG cases compared with multiport laparoscopic total gastrectomy (MLTG) or proximal gastrectomy (MLPG) for EGC. METHODS: We analyzed all consecutive SITG or SIPG cases with double-tract reconstruction for ECG, including the initial case, between March 2013 and December 2021. SITG/SIPG was performed on patients without significant systemic comorbidities through a 3-4 cm vertical transumbilical incision. SITG/SIPG was matched to multiport laparoscopic total or proximal gastrectomy (MLTG/MLPG) cases performed in the same period using a 1:3 propensity score matching, including sex, body mass index (BMI), age and type of resection, year of operation, and institution as covariates. We compared perioperative clinicopathological characteristics and early postoperative morbidity within 1 month after surgery between the SITG/SIPG and MLTG/MLPG groups. RESULTS: In total, 21 patients with SITG and 15 patients with SIPG were compared with those with MLTG (n = 264) and MLPG (n = 220). No conversion to an open or multiport approach occurred in the SITG/SIPG group. After matching, operation time was similar between SITG/SIPG and MLTG/MLPG (223.9 ± 63.5 min vs 234.8 ± 68.7 min, P = 0.402). Length of stay was not significantly different between SITG/SIPG and MLTG/MLPG (11.9 ± 15.4 days vs 8.4 ± 5.0 days, P = 0.210). The average number of retrieved lymph nodes was not significantly different between SITG and MLTG (53.1 ± 16.3 vs 63.2 ± 27.5, P = 0.115), but it was significantly higher in SIPG than MLPG (59.6 ± 27.2 vs 46.0 ± 19.7, P = 0.040). The overall complication rate (30.6% vs 25.9%, P = 0.666) and Clavien-Dindo grade III or higher complication rates (13.9% vs 6.5%, P = 0.175) were not significantly different between the SITG/SIPG and MLTG/MLPG groups. CONCLUSION: Cautious adoption of SITG/SIPG procedures for EGC is feasible and safe.

Safety and Efficacy of Intraperitoneal Paclitaxel Plus Intravenous Fluorouracil, Leucovorin, and Oxaliplatin (FOLFOX) for Gastric Cancer with Peritoneal Metastasis.

BACKGROUND: Peritoneal metastasis (PM) remains a major obstacle in the treatment of stage IV gastric cancer. This is a dose-escalation study of intraperitoneal (IP) paclitaxel combined with intravenous (IV) fluorouracil, leucovorin, and oxaliplatin (FOLFOX) to determine the recommended phase II dose in gastric cancer patients. METHODS: Patients with gastric adenocarcinoma and PM were enrolled. The recommended phase II dose of IP paclitaxel was determined using the standard "3 + 3" dose escalation with planned doses ranging from 40 to 100 mg/m2. IV FOLFOX was administered on the same day (oxaliplatin 100 mg/m2 (day 1), leucovorin 100 mg/m2 (day 1), fluorouracil 2,400 mg/m2 over 46 hours (day 1)). Both IP and IV regimens were repeated every 2 weeks. RESULTS: Among the 13 patients, there was no DLT at 40 and 60 mg/m2. Two patients had grade 3 febrile neutropenia at 80 mg/m2, and the recommended phase II dose was 60 mg/m2. Other patients underwent IP paclitaxel and FOLFOX without serious adverse events. Seven patients underwent second-look diagnostic laparoscopy, and the average change in PCI score was -7.0 ± 9.7. Conversion surgery rate was 23.1% (n = 3). The median overall survival was 16.6 months (95% confidence interval, 16.6-N/A), and progression-free survival was 9.6 months (95% confidence interval, 4.7-N/A). All adverse events were tolerable and manageable. CONCLUSIONS: The biweekly regimen of IP paclitaxel and FOLFOX is safe and the recommended dose of IP paclitaxel for a phase II trial is 60 mg/m2.

Should total omentectomy be performed for advanced gastric cancer?: The role of omentectomy during laparoscopic gastrectomy for advanced gastric cancer.

BACKGROUND: In the era of minimally invasive surgery, laparoscopic partial omentectomy (LPO) has seen widespread use as a curative surgical procedure for early gastric cancer. However, scientific evidence of the extent of omentectomy during laparoscopic gastrectomy remains unclear for advanced gastric cancer (AGC). METHODS: We analyzed 666 eligible patients who underwent laparoscopic gastrectomy for AGC with curative intent between 2014 and 2018. Surgical outcome and postoperative prognosis were compared between LPO and laparoscopic total omentectomy (LTO) groups after 2:1 propensity score matching with age, sex, body mass index, tumor size, pT stage, pN stage, gastrectomy type, and clinical T stage as covariates. RESULTS: After extensive matching, there was no significant difference in pathologic or clinical stages between the LPO (n = 254) and LTO (n = 177) groups. LPO provided a significantly shorter operation time than LTO (199.2 ± 64.8 vs. 248.1 ± 68.3 min, P < 0.001). Pulmonary complication within postoperative 30 days was significantly lower in the LPO group (4.4 vs. 10.3%, P = 0.018). In multivariate analysis, LTO was the independent risk factor for pulmonary complication (odds ratio [OR] 2.53, 95% confidence interval [95% CI] 1.12-5.73, P = 0.025), which became more obvious in patients with a Charlson's comorbidity index of 4 or higher (OR 27.43, 95% CI 1.35-558.34, P = 0.031). The 5-year overall survival rate (OS) and 3-year recurrence-free survival (RFS) rates were not significantly different between the two groups, even after stage stratification. CONCLUSION: LPO provided significantly shorter operation time and less pulmonary complication than LTO without compromising 5-year OS and 3-year RFS for AGC. LTO was the independent risk factor for pulmonary complications, which became more evident in patients with severe comorbidities.

Three-dimensional (3D) visualization provides better outcome than two-dimensional (2D) visualization in single-port laparoscopic distal gastrectomy: a propensity-matched analysis.

PURPOSE: There are currently no reports on the application of three-dimensional (3D) vision to single-incision laparoscopic surgery. This study compared 3D vision to the previous two-dimensional (2D) system in single-incision laparoscopic distal gastrectomy (SIDG). METHODS: Medical charts of 179 gastric cancer patients who underwent SIDG from February 2014 to December 2017 were retrospectively reviewed. Patients were grouped into either a 2D group or 3D group depending on the type of camera that was used. All operations were performed using a flexible camera (Olympus, Japan). Operative data and postoperative outcome were analyzed. RESULTS: There were 90 patients in the 2D group and 89 patients in the 3D group. No differences were found in terms of the age, body mass index, staging, and other demographics of the patients. Operative time was significantly faster in the 3D group (115.6 ± 34.0 vs. 129.4 ± 38.5 min, p = 0.012), and estimated blood loss (EBL) was less in the 3D group (20.7 ± 30.0 vs. 35.1 ± 56.0 ml, p = 0.034). Patients in the 3D group were able to start a small fluid diet earlier (2.5, range 1-6 vs. 3.0, range 2-8 postoperative days, p = 0.006) and were discharged faster (5.4, range 3-12 vs. 6.2, range 4-24 postoperative days, p = 0.024). There was no statistical difference between early and late complications. CONCLUSION: The use of the 3D camera shortened operative time with possible clinical benefits for patients undergoing SIDG.

Single-Incision Proximal Gastrectomy With Double-Flap Esophagogastrostomy Using Novel Laparoscopic Instruments.

Background. The optimal type of anastomosis after proximal gastrectomy (PG) is still controversial. A novel technique termed "double-flap" esophagogastrostomy (EG) has been introduced. The application of this technique after PG is reported to have little gastroesophageal reflux without the need of creating an esophagojejunostomy. However, this procedure is technically challenging and hence difficult to apply in laparoscopic PG. This technical report describes in detail how to perform single-incision proximal gastrectomy (SIPG) with double-flap EG with the use of novel laparoscopic instruments. Methods. Two patients diagnosed with early gastric cancer underwent SIPG. A 2.5 cm incision was made, and a scope holder was used in place of a scopist. After performing PG with D1+ lymphadenectomy, double seromuscular flaps were created on the anterior wall of the stomach. After tagging the esophagus to the inferior edge of the flap window, the stomach and esophagus were opened through electrocautery. EG was performed intracorporeally using continuous barbed sutures, and the flap is then secured to the anastomosis. To facilitate this procedure, an intra-abdominal organ retractor and an articulating needle holder were used. The supplementary video illustrates in detail how these devices are used to perform the technique. Results. Total operation times were 190 and 110 minutes each, and anastomosis took 75 and 46 minutes each. Patients had no complications and were both discharged on postoperative day 6. Conclusion. Double-flap PG is technically feasible through a single incision with the use of articulating laparoscopic devices and intra-abdominal organ retractors to assist in intracorporeal anastomosis.

Laparoscopic surgery for gastric cancer: Current status and future direction.

Gastric cancer is still a major cause of death worldwide. While laparoscopic gastrectomy (LG) has gained evidence as a standard treatment for early gastric cancer in the distal stomach, there are still concerns regarding its application for gastric cancer in the upper stomach and advanced gastric cancer. Nevertheless, LG has shown to have faster recovery, shorter hospital stay, less pain, and less blood loss in many retrospective and prospective studies. The application of LG has now extended from conventional radical gastrectomy to novel approaches such as function-preserving gastrectomy and sentinel-node navigated surgery. Studies on the use of laparoscopy in treatment for stage IV gastric cancer are rare, but show that there may be some roles of LG in selected cases. With the development of new laparoscopic tools that augment human ability, the future of LG should move on from proving non-inferiority to demonstrating superiority compared to the traditional open gastrectomy.

Mid- to Long-Term Outcomes in Management of Spontaneous Isolated Coeliac Artery Dissection (SICAD).

OBJECTIVE: Spontaneous Isolated Coeliac Artery Dissection (SICAD) is a rare disease with few reports of management strategies. This study reports the mid- to long-term outcomes of conservative management and endovascular intervention of SICAD treatment. METHODS: Sixteen patients presenting with symptomatic SICAD from September 2006 to October 2018 were reviewed retrospectively. The clinical manifestations, initial radiological findings, methods of treatment, and serial follow up studies were analysed. RESULTS: The mean age of the patients was 51.2 ± 7.9 years, with a median follow up of 33.3 (range 1.0-118.9) months. Four patients received early intervention because of aneurysmal dilatation or distal hypoperfusion. Four patients who received conservative management showed progression of disease and were recommended for delayed intervention. Although collaterals prevented further hepatic ischaemia, one of these four patients failed in delayed intervention because of extensive thrombi completely occluding the hepatic artery. In the remaining eight patients who were managed conservatively, three (37.5%) showed regression of disease, one (12.5%) showed partial regression, and five (62.5%) showed no change in intimal flap or thrombosis, but all had symptomatic improvement. The median follow up duration for the seven patients who underwent successful intervention was 77.3 (range 34.3-118.9) months, and all stenting remained patent during the follow up period. CONCLUSION: Early intervention in symptomatic SICAD patients may be necessary in over 50% of patients, and endovascular stenting has durable long term outcomes.

Early experience and learning curve of solo single-incision distal gastrectomy for gastric cancer: a review of consecutive 100 cases.

BACKGROUND: Single-incision distal gastrectomy (SIDG) is technically difficult due to limited range of motion and unstable field of view. Solo surgery using a passive scope holder may be the key in allowing SIDG to be safer and efficient. We report our initial 100 cases of, to what we know, the world's first solo SIDG, and calculate the learning curve. METHODS: Prospectively collected database of 100 patients clinically diagnosed as gastric cancer who underwent solo SIDG from October 2013 until July 2016 was analyzed. All the operations were held by a single surgeon with no assistants. A passive laparoscopic scope holder was used to fix the field of view. RESULTS: The mean operation time was 120.6 ± 30.2 min, and the average estimated blood loss was 33.5 ± 55.7 ml. Average body mass index was 23.4 ± 2.9 kg/m2. The median hospital stay was 5 (4-14) days, and the mean number of retrieved lymph nodes was 56.0 ± 22.8. There was no conversion to multiport or open surgery. Early complication of Clavien-Dindo grade III or more was 3%. Learning curve was calculated on operation time, and showed that an experienced surgeon in SIDG required 20 cases or less in stabilizing the operation time for solo SIDG. CONCLUSIONS: Solo SIDG seems to be feasible and safe. The stable field of view created by a scope holder provides a favorable environment for a finer and more consistent operation. In addition, manpower can also be saved without affecting the quality of surgery.

Intracorporeal overlap gastro-gastrostomy for solo single-incision pylorus-preserving gastrectomy in early gastric cancer.

This report discusses the technique of solo single-incision pylorus-preserving gastrectomy (SIPPG) for early gastric cancer. To overcome difficulties regarding lymph node dissection (LND), a scope holder and an energy device were used, allowing fine dissection in a fixed field of view. The overlap gastro-gastrostomy technique was used for anastomosis. Seventeen patients underwent solo SIPGG. The mean operation time was 150.1 ± 28.7 min, and no patients developed postoperative complications or delayed gastric emptying within 30 days of the operation. Using scope holders and performing fine dissection with the energy device, challenges regarding LND in SIPPG can be overcome. INTACT anastomosis was initially used; however, due to its inconsistency and the high degree of surgical skill required, it was changed to the overlap method. Solo SIPPG with overlap gastro-gastrostomy may be safe and feasible with good cosmetic results and fast patient recovery.

Multimodal Enhanced Recovery After Surgery (ERAS) Program is the Optimal Perioperative Care in Patients Undergoing Totally Laparoscopic Distal Gastrectomy for Gastric Cancer: A Prospective, Randomized, Clinical Trial.

BACKGROUND: The application of ERAS protocol has widely gained acceptance after gastrointestinal surgery. Well-designed, randomized, control trials are needed to evaluate fully its safety and efficacy in the field of gastric cancer. This study aims to compare the enhanced recovery after surgery (ERAS) protocol and the conventional perioperative care program after totally laparoscopic distal gastrectomy (TLDG) in gastric cancer. METHODS: Patients with gastric cancer indicated for TLDG were randomly assigned to either the ERAS group or the conventional group. The ERAS protocol included short fasting time, fluid restriction, early oral feeding, immediate mobilization, and use of epidural patient-controlled analgesia. Primary endpoint was recovery time, which was defined with the criteria of tolerable diet, safe ambulation, no requirement of additional analgesics, and afebrile state. Hospital stay, pain score, complications, and readmission rate were secondary endpoints. RESULTS: A total of 97 patients who underwent TLDG from October 2012 to August 2014 were enrolled (ERAS = 46, conventional = 51). The ERAS group had faster recovery time (111.6 ± 34.3 vs. 126.7 ± 30.7 h; p = 0.026) and significantly less pain through postoperative days 1-4. Possible hospital stay also was faster in the ERAS group (5.0 ± 1.9 vs. 5.7 ± 1.6 days, p = 0.038), but there was no difference in actual hospital stay. No difference was found in complication, and there was no mortality or readmission in both groups. CONCLUSIONS: ERAS is safe and enhances postoperative recovery after TLDG in gastric cancer. TRIAL REGISTRATION: The trial was registered in ClinicalTrials.gov (NCT01938313).

A prospective randomized trial comparing the efficacy of temperature-responsive gel with local anesthetics versus local anesthetic infusion pump device for postoperative pain control after bariatric surgery.

Purpose: Bariatric surgery is the gold standard for the treatment of morbid obesity, but postoperative pain impedes recovery. Currently available pain-recovery treatments have patient safety concerns. This led to a noninferiority study of Welpass (Genewel Co., Ltd.) vs. On-Q PainBuster (B. Braun), each used alongside a traditional method of continuous local anesthetic administration, in patients undergoing bariatric surgery. Methods: In this single-center prospective randomized clinical trial, patients were assigned in a 1:1 ratio to the treatment group (Welpass) and the control group (On-Q PainBuster), with ketorolac administered as needed after surgery according to the protocol. To assess efficacy, the total amount of ketorolac used up to 72 hours postoperatively was measured. Additionally, ketorolac usage and numerical rating scales (NRS) were recorded at 6, 24, 48, and 72 hours after operation. Results: The total amounts of ketorolac used in the 72 hours postoperatively were 188.0 ± 84.6 mg in the treatment group and 198.7 ± 50.0 mg in the control group. The efficacy of the treatment group was noninferior to that of the control group, since the lower limit (-29.9 mg) of the confidence interval for the difference with the control group was greater than the prespecified noninferiority margin (-35.0 mg). Furthermore, when the NRS was evaluated after bariatric surgery, there was no significant difference in scores between the 2 groups at each time point (P > 0.05). Conclusion: We found no difference in effect on pain between the 2 groups, supporting the use of Welpass in clinical practice for pain management in patients undergoing bariatric surgery.