Blood Flow Monitoring to Prevent Post-Polypectomy Induced Ulcer Bleeding

The primary specific aim is to perform a randomized controlled trial (RCT) to compare rates of delayed hemorrhage after DEP detection of arterial blood flow and focal treatment in PPIU's (treatment arm) with standard treatment using medical guidelines alone (controls) for prevention of delayed bleeding in high risk patients (on anti-coagulants or anti-platelet drugs or with large ulcers) after snare resection of benign colon polyps.

VA Central Office recently opened back research study after suspension from March to Sept 2020 with COVID 19

Severe delayed post-polypectomy induced ulcer (PPIU) bleeding has become a much more common problem with the increased numbers of colonoscopies being performed and with more patients taking anti-coagulants or anti-platelet drugs. Current medical guidelines may reduce bleeding during polypectomy, but are not effective for prevention of delayed bleeding. Empiric closure of PPIU's with clips is not effective because ulcers \> 15 mm cannot be closed, does not treat the underlying artery in the ulcer base, and when the clips often fall off within 7 the underlying artery is exposed. As preliminary results, the investigators studied delayed PPIU bleeds and their prevention, used a Doppler endoscopic probe (DEP) to localize arteries in PPIU's, reported the prevalence which rises significantly as ulcer size increases, and successfully obliterated blood flow with focal treatment. These studies form the basis for this new RCT. The primary specific aim is to perform a RCT to compare rates of delayed hemorrhage after DEP detection of arterial blood flow and focal treatment in PPIU's (treatment arm) with standard treatment using medical guidelines alone (controls) for prevention of delayed bleeding in high risk patients (on anti-coagulants or anti-platelet drugs or with large ulcers) after snare resection of benign colon polyps. Secondary specific aims are to evaluate the natural history and risk factors for delayed PPIU bleeding using univariate and multivariable analyses. This is a RCT performed by the CURE Hemostasis Research Group for high risk patients - those with PPIU's 15 mm in size or greater but not on drugs associated with bleeding; or patients who require anti-coagulants or anti-platelet drugs for treatment of co-morbid conditions and have PPIU's 10 mm or larger. Outpatients, scheduled for screening or surveillance colonoscopies, who give written informed consent and meet entry criteria will be randomized to control/no DEP (medical treatment without PPIU closure) or DEP (as a guide to arterial blood flow detection and focal obliteration of it with hemoclips and/or low power multipolar electrocautery \[MPEC\] probe). Patients will be prospectively followed at 7, 14, and 30 days for bleeding, complications, or unscheduled visits for healthcare after polypectomies.

Eligibility Criteria:
Inclusion Criteria:

* Ambulatory patients, 35 years old or more and who are having:

  * elective, outpatient screening
  * surveillance colonoscopy for colon cancer or polyps
  * or being evaluated for abdominal pain or change in bowel habits ---or have a large polyp needing removal by EMR or ESD
* Clinically the patient has to have a medical indication and recommendation by their primary care physician (PCP) or specialist to take:

  * daily anti-coagulants (Warfarin, low-molecular-weight heparin \[LMWH\] or a newer agent)
  * or an anti-platelet drug (aspirin as 81 mg or more, Clopidogrel, or newer agents) for PPIU's 10-14mm
  * or if not on one of these drugs, they must have a PPIU 15 mm
* On colonoscopy, they are required to have:

  * benign appearing polyps and for 1 or more PPIU to be 10 mm in size (for the anti-coagulant or anti-platelet groups)
  * or 15 mm or larger for the PPIU group who do not have to be (but may be) on these drugs that can induce bleeding
* In the case of bleeding from the PPIU during polypectomy, hemorrhage must be completely controlled

Exclusion Criteria:

* Inability or unwillingness to give written informed consent or to return to the investigators' medical centers for follow-up (FU) in the next 30 days, in case of delayed bleeding or other complications
* Intrinsic bleeding disorder with a history of recurrent bleeding either after:

  * surgeries
  * angiography
  * or other invasive procedures
* Significantly abnormal coagulation tests related to co-morbid liver, hematologic, or infectious disorders and not anti-coagulant drugs, with platelet count \< 100,000; international normalized ratio (INR) \> 1.5; or partial thromboplastin time (PTT) more than 1.5 times normal
* Inflammatory bowel disease
* Infectious colitis
* Idiopathic colitis with a history of recurrent rectal bleeding
* Recurrent rectal bleeding from another chronic colorectal condition such as:

  * colonic angiomas
  * radiation colitis
  * proctitis
  * or internal hemorrhoids
* A sessile polyp that can not be raised up by saline injection or Endoscopic mucosal resection (EMR) techniques nor completely removed by snare polypectomy either en block or in pieces and there is a suspicion about possible malignancy by the colonoscopist.
* Recently colonoscopy (within less than 3 years) unless the patient is referred for a large or multiple polyps (on more recent colonoscopy) and colonoscopic removal in the investigators' referral centers