Blood supply of colorectal polyps correlates with risk of bleeding after colonoscopic polypectomy.
BACKGROUND: The most common complication of endoscopic polypectomy is hemorrhage. Several factors have been reported to increase the risk of hemorrhage after polypectomy, but controversies still exist. Additionally, the pathomechanism of this complication is not well understood. OBJECTIVE: To investigate the risk factors of colonoscopic postpolypectomy bleeding in patients without bleeding disorders and the blood supply of resected polyps. PATIENTS: Two hundred forty-five patients (147 men, 98 women; median age, 62.8 +/- 9.5 years [SD]) with 283 colorectal polyps, measuring > or =1 cm in diameter, were included in this prospective study. INTERVENTIONS: The polypectomies were performed using the conventional endoscopic method. Data on the patients' age and sex, as well as polyp location, size, shape, and pathology findings were recorded. The patients were observed for bleeding complications. Microscopic examination of the vascular supply of the removed polyps was performed. RESULTS: Twenty-nine postpolypectomy hemorrhages (10.2%) occurred. The bleeding rate correlated with the size, shape, and pathology results of resected polyps. The microscopic analysis revealed that sessile and thick-stalked pedunculated polyps are supplied with more vessels than other polyps. CONCLUSIONS: Patients with polyps larger than 17 mm, pedunculated polyps with a stalk diameter >5 mm, sessile polyps, and malignant lesions of the colorectal region are at high risk of hemorrhage after endoscopic excision. Moreover, on the basis of microscopic study, broad-based polyps are supplied with a considerable number of blood vessels.