Aspirin effects on colonic mucosal bleeding: implications for colonic biopsy and polypectomy.
BACKGROUND
Many patients who require endoscopic treatments such as biopsy and polypectomy are given antiplatelet agents reluctantly. We have studied the effects of aspirin on colonic mucosal hemostasis.


METHODS
We developed a new endoscopic device to make a standard incision (7-mm length) on the colonic mucosa to study colon bleeding time. We measured the colon bleeding time of normal colonic mucosa in 47 cases. The colon bleeding time and skin bleeding time (Simplate method) were measured before and one hour after aspirin ingestion (990 mg) in ten healthy subjects.


RESULTS
The bleeding time of normal colonic mucosa was 156 +/- 71 (mean +/- standard deviation) seconds. Significant prolongation was noted in both skin bleeding time (357 +/- 192 vs. 477 +/- 183 seconds; P < 0.05) and colon bleeding time (155 +/- 47 vs. 244 +/- 169 seconds; P < 0.05) after aspirin ingestion.


CONCLUSIONS
Bleeding time was measured safely under direct colonoscopic visualization. Aspirin prolonged the colon bleeding time. Therefore, endoscopists should be aware of a risk of abnormal bleeding after endoscopic biopsy and polypectomy in patients with aspirin use. Two days were necessary for colon bleeding time to become normalized in patients with aspirin use.
Nakajima
H
H
Department of Medicine, Kuroishi City Hospital, Hirosaki University School of Medicine, Aomori, Japan.
Takami
H
H
Yamagata
K
K
Kariya
K
K
Tamai
Y
Y
Nara
H
H
D001241:Aspirin / Q000008:administration & dosage*; D001706:Biopsy; D001760:Bleeding Time; D001777:Blood Coagulation / Q000187:drug effects*; D003108:Colonic Diseases / Q000209:etiology / Q000378:metabolism*; D003113:Colonoscopy / Q000009:adverse effects; D004724:Endoscopy / Q000009:adverse effects; D006471:Gastrointestinal Hemorrhage / Q000209:etiology / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000098:blood supply* / Q000601:surgery; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D015203:Reproducibility of Results
D010975:Platelet Aggregation Inhibitors; D001241:Aspirin