Enhancing anastomosis safety with intraoperative perfusion assessment: a visual grading system for tailoring resection and ostomy formation in sigmoid colon and rectal cancer surgery.

Abstract

Purpose: Anastomotic leakage remains challenging in left-sided colorectal surgery. We previously proposed a 5-grade visual grading system based on marginal vessel bleeding, indicating that good (grades A/B) to moderate (grade C) perfusion generally ensures safe anastomosis. However, borderline perfusion (grade C) carried additional risk, particularly among older patients or those with comorbidities. We refined this system to determine whether selective resection of grade C bowel could improve perfusion and guide ostomy diversion decisions.

Methods: Eighty patients with left-sided colorectal cancer underwent curative-intent surgery. Intraoperatively, both marginal vessel and mucosal bleeding were assessed. Initial perfusion grade-guided decision-making: grades A/B proceeded to anastomosis, whereas for grade C, additional resection was performed to upgrade perfusion. Ostomy diversion was performed for persistent grade C or prophylactically in high-risk patients.

Results: Among 80 patients, 67 (83.8%) had grades A/B and 13 (16.3%) were initial grade C. Additional resection (mean, 4.5 cm) upgraded perfusion to final grade B in 9 patients (69.2%), enabling primary anastomosis. Overall, 12 patients (15.0%) received ostomy: 4 for persistent grade C and 8 for high-risk indications despite adequate final perfusion. All 76 patients with final grade A/B achieved 0% anastomotic leakage and ischemic colitis. Grade C patients had longer operative times (108.8 minutes vs. 86.6 minutes, P=0.003) with additional procedures. Patients requiring diversion were older with more comorbidities.

Conclusion: By actively applying the intraoperative visual grading system to upgrade borderline perfusion, we achieved low postoperative complication rates. This approach provides a simple and practical strategy to support intraoperative clinical judgment and optimize anastomotic safety.