Abstract
Background Delayed bleeding is the most common significant complication after piecemeal endoscopic
mucosal resection (p-EMR) of large nonpedunculated colorectal polyps (NPCPs). Risk
factors for delayed bleeding are incompletely defined. We aimed to determine risk
factors for delayed bleeding following p-EMR.
Methods Data were analyzed from a prospective tertiary center audit of patients with NPCPs ≥ 20 mm
who underwent p-EMR between 2010 and 2012. Patient, polyp, and procedure-related data
were collected. Four post p-EMR defect factors were evaluated for interobserver agreement
and included in analysis. Delayed bleeding severity was reported in accordance with
guidelines. Predictors of bleeding were identified.
Results Delayed bleeding requiring hospitalization occurred after 22 of 330 procedures (6.7 %).
A total of 11 patients required blood transfusion; of these, 4 underwent urgent colonoscopy,
1 underwent radiological embolization, and 1 required surgery. Interobserver agreement
for identification of the four post p-EMR defect factors was moderate (kappa range
0.52 – 0.57). Factors associated with delayed bleeding were visible muscle fibers
(P = 0.03) and the presence of a “cherry red spot” (P = 0.05) in the post p-EMR defect. Factors not associated with delayed bleeding were
American Association of Anesthesiologists class, aspirin use, polyp size, site, and
use of argon plasma coagulation.
Conclusions Visible muscle fibers and the presence of a “cherry red spot” in the resection defect
were associated with delayed bleeding after p-EMR. These findings suggest evaluation
and photodocumentation of the post p-EMR defect is important and, when considered
alongside other patient and procedural factors, may help to reduce the incidence and
severity of delayed bleeding.
