GASTROENTEROLOGY ARTICLE OF THE WEEK
September 3, 2009
Monkemuller K, Neumann H, Malfertheiner P and Fry LC. Advanced colon polypectomy. Clin Gastroenterol Hepatol 2009;7:641-652.
1. When removing polyps from the right colon
a. Hot biopsy technique is particularly helpful for small right sided colon polyps
b. Decompress the colon partially before closing the snare around the polyp
c. Inject saline on the proximal side of the polyp if sessile
d. Use a closed snare and cautery to fulgurate any remaining polypoid tissue
e. After snaring the polyp, creat a “tent” to keep the current at the base of the polyp
2. Correct technique for injection assisted polypectomy:
a. Inject the polyp proximally first (closest to the mouth)
b. Introduce the injector in the mucosa as deep as possible
c. Inject while retrieving the needle
d. Needle angle should be almost perpendicular to the mucosa, no more than 30% elevation
e. In most cases 5-10cc are needed
True or False
3. Epinephrine submucosal injection is more likely to be systemically absorbed quickly in the right colon than the rectum
4. Using pure cut current is associated with a higher immediate bleeding rate but lower delayed bleeding and lower perforation rates compared to blend or coagulation
5. APC current setting to “mop up” residual tissue after piecemeal polypectomy should be 30W in the right colon and 60W in the left colon and rectum, flow 1-2 L/min.
6. If cardiac toxicity of epinephrine injection in the rectum is undesirable, you can use D50 to lift up the polyp
7. Risks of bleeding and post-polypectomy syndrome after injection assisted polypectomy are 11% and 4% respectively.
8. Bleeding after injection assisted polypectomy should be treated with epinephrine injection and APC or heater probe.
9. Injecting epinephrine into the head of a large pedunculated polyp may reduce the size of the head and make polypectomy easier
10. Removal of a large colon polyp by laparoscopy is safer than endoscopic submucosal resection
11. Cold snare removal of polyps is safer but inferior (leaves residual neoplastic tissue) compared to hot biopsy removal.
12. The best position in the screen to place a polyp for polypectomy is the 5 to 6 o’clock position.
13. If a post-polypectomy perforation is noted 20 hours after the colonoscopy, an approach could be repeat colonoscopy with closure of the perforation using clips
14. Current data available does not show an increased risk of bleeding after polypectomy in patients taking NSAID’s, aspirin or clopidogrel.
15. Sessile polyps as large as 2cm in diameter can be safely removed in one piece from the cecum
16. Polyps that are over 1cm in size and sessile should be removed using injection-assisted polypectomy
17. Patients with more than 10 polyps should probably undergo repeat colonoscopy to finish removal of polyps