Warm staple-line irrigation (37–40 °C) before omentopexy reduces early bleeding after laparoscopic sleeve gastrectomy: a prospective, randomized trial

BACKGROUND: Early bleeding remains a common concern after laparoscopic sleeve gastrectomy (LSG), despite improvements in stapling technology and reinforcement techniques. This study examined whether using warm saline to irrigate the staple line before performing omentopexy could enhance intra-operative hemostasis and reduce early postoperative bleeding. METHODS: In this prospective randomized trial conducted between December 2024 and June 2025, 200 adults undergoing primary LSG were allocated equally to warm saline irrigation (37-40 °C) or conventional room-temperature irrigation (22-24 °C), reflecting two clinically relevant intraoperative strategies in routine laparoscopic practice. Irrigation was applied directly to the staple line, followed by complete suctioning, careful inspection, and standardized omentopexy using 2-0 PDS sutures spaced 2 cm apart. The primary endpoint was a 48-h composite of early postoperative bleeding, defined as clinical bleeding, need for endoscopic or surgical control, hemoglobin drop (ΔHb) ≥ 2 g/dL on postoperative day 1, or drain output ≥ 150 mL in the first 24 h. Secondary outcomes included hemostasis time, ΔHb, drain volume, pain scores, postoperative nausea and vomiting (PONV), length of stay (LOS), and 30-day complications. This trial was powered for a composite bleeding endpoint rather than rare major bleeding events. RESULTS: Baseline characteristics were similar between groups. The composite bleeding endpoint occurred in 5% of patients receiving warm irrigation versus 15% in the control group (p = 0.02). Warm irrigation also resulted in lower drain output (82 ± 31 vs 128 ± 46 mL; p < 0.001) and a smaller ΔHb drop (1.28 ± 0.52 vs 2.06 ± 0.61 g/dL; p < 0.001). Pain scores were modestly lower at 24 h. LOS, PONV, readmission rates, and leak rates were comparable. CONCLUSION: Warm saline irrigation may improve hemostasis and early bleeding-related outcomes after LSG. However, given the composite nature of the primary endpoint and the limited sample size for rare complications, these findings should be interpreted cautiously, and larger multicenter studies are needed for confirmation. TRIAL REGISTRATION: ClinicalTrials.gov (NCT07475169), retrospectively registered on 12 February 2026.