Preventing Postpolypectomy Bleeding: Obligatory and Optional Steps

Postpolypectomy bleeding is often an unpredictable event that creates great anxiety for all concerned and, like all complications, is best avoided. The study by Di Giorgio et al. [1] published in this month’s edition of Endoscopy provides useful new evidence to guide us in strategies aimed at preventing bleeding after polypectomy.

The incidence of postpolypectomy bleeding is between 0.2 % and 3 % [2], while the other significant complications - namely, postpolypectomy coagulation syndrome (0.5 - 1 %) [3] and perforation (0.5 %) [4] - are less frequent. Postpolypectomy bleeding can be characterized in different ways. It is defined as ”immediate” when bleeding occurs during the procedure such that endoscopic intervention is required; or as ”delayed” if it occurs after the colonoscopy has been completed. Delayed bleeding generally presents within the first few days [3] [5], but has been reported to occur as long as 30 days after polypectomy [6]. Immediate bleeding is usually due to inadequate coagulation of vessels in the polyp stalk or base, whereas delayed bleeding is thought to relate to detachment of the eschar several days after polypectomy, when a significant submucosal vessel is exposed [5]. The risk of either immediate or delayed bleeding is therefore dependent, at least in part, on the amount of tissue coagulation - too little and immediate bleeding is likely, too much and deep tissue injury with the risk of delayed bleeding may occur. The degree of tissue injury incurred depends on the power settings and duration of current application, the type of current used, and - most importantly - the force applied to the snare during closure. For this reason, we strongly recommend (and teach) that endoscopists should become familiar with closing the snare themselves during diathermy application, so that they can develop a ”feel” to guide the speed of cutting, while also observing for visible whitening of the polyp stalk on the video monitor. Most colonic polypectomies can be carried out using low-power diathermy settings, predominantly set to a coagulating current. Polypectomy using pure cutting current, which vaporizes tissue, may be associated with a higher risk of immediate bleeding [5] [7]. Coagulating current heat-seals the blood vessels and is ideal for resecting large, stalked polyps in which the feeding vessels are often sizeable and the risk of damage to the bowel wall, remote from the stalk, is small. Postpolypectomy bleeding can also be graded as mild, moderate, or severe, depending on alterations in the haemoglobin level, transfusion requirements, or whether angiography or surgery become necessary. Fortunately, the majority of postpolypectomy bleeds are mild and self-limiting [8], and conservative management is therefore usually sufficient. Only a few patients with persistent bleeding requiring repeat colonoscopy or other interventions.

What are the risk factors for bleeding after polypectomy? There appear to be several that are worth considering. With regard to the polyp itself, size is important [9]. A pedunculated polyp with a large head (> 2 cm) [2] [10] or stalk (and larger feeding artery) [10] [11], as well as large sessile polyps, are associated with a higher risk for bleeding [11] [12]. The relative experience of the endoscopist [2], the presence of coagulopathy or anticoagulant therapy [13], and a proximal location of the polyp in the colon [14] have also been implicated. There is a wide consensus and considerable data to suggest that low-dose aspirin does not increase the risk of postpolypectomy bleeding. After a multivariate analysis of 1657 polypectomy cases, Hui et al. recently suggested that only warfarin usage was associated with an increase in bleeding rates [15]. Definitive data on the risk of polypectomy in patients taking newer antiplatelet drugs such as clopidogrel are not yet available, and caution is advised. Nakajima et al. demonstrated that colonic bleeding is prolonged after aspirin and takes 2 days to normalize once aspirin is discontinued [16]. Antiplatelet agents are therefore likely to make bleeding more severe if it occurs and should be stopped as soon as bleeding becomes apparent.

In order to avoid the more severe consequences of bleeding, several novel approaches have been developed to encourage haemostasis after the removal of high-risk polyps and in patients who are more likely to suffer bleeding. These include mechanical devices such as detachable snares, clips, and band ligation; adjunctive thermal modalities such as argon plasma coagulation, heater and gold probes, and hot biopsy forceps; and the use of injection therapy with saline or hypertonic saline mixed with epinephrine. Sclerosants are no longer used as much, because of the perceived increased risk of perforation. The detachable snare for haemostasis during removal of pedunculated polyps was originally developed in the 1980s [17] [18]. The ”Endoloop” as it is now known is a popular choice for endoscopists, as it can be placed around the stalk before or after snare resection. Placement of the loop over stalked polyps with heads < 2 cm in size is usually straightforward, although inexperience can mean the loop slips off if it is positioned too near the resection margin (or if the stalk is too short in which case an alternative method should be used). As the nylon loop is more floppy than a standard snare, passing the loop over a large-headed polyp can be difficult to do before polypectomy. Conversely, snaring the stalk once the head has been resected is technically easy, but does not protect against immediate arterial spurting should this occur, which can make the placement of the loop awkward. The loop will eventually fall off by itself 2 - 3 weeks after deployment [19].

Several studies have shown that using epinephrine injection [12] [20] [21] or an Endoloop [22] [23] before polypectomy is safer than conventional polypectomy alone, but the two haemostatic methods have not previously been compared. The study by Di Giorgio et al. [1] is a straightforward comparative one in which 488 consecutive patients with pedunculated colorectal polyps (> 1 cm) were randomly assigned, after anticoagulant treatment and anti-platelet agents had been stopped, into three groups who received an Endoloop, or an injection of 1 : 10 000 epinephrine, or no intervention before polypectomy. If bleeding occurred, it was classified as early (< 24 h) or late (> 24 h - 30 days). At the end of the study, the calculated overall incidence of bleeding was 4.3 %. Rates were highest (7.9 %) in the control group and comparable between the Endoloop (1.8 %) and epinephrine (3.1 %) groups when polyps of all sizes were included (no significant differences between groups). After further subgroup analysis, there were no differences between the groups if polyps < 2 cm were considered, but these differences became significant for polyps 2 cm or more in size (bleeding occurred in 2.7 % after Endoloop application, in 2.9 % after epinephrine, and in 15.1 % without intervention; P < 0.05). Although the numbers were small, most of the reduction in bleeding rates either with Endoloop or epinephrine appeared to occur in the immediate phase, while late or delayed bleeding rates were similar to those in the nonintervention group - suggesting that the effects of either intervention may not last.

What lessons can be learned to help avoid postpolypectomy bleeding?

Firstly, it is important to make patients aware that bleeding will occasionally occur, regardless of the size of the polyp, and to provide them with contact numbers in case of emergency. Secondly, it is essential to recognize which patients are at high risk for bleeding. Warfarin should be discontinued whenever possible (if necessary heparin can be temporarily substituted and then stopped prior to polypectomy), and clotting status should be checked before the polypectomy. Although the current American Society for Gastroenterology (ASGE) guidelines 24 suggest that aspirin and nonsteroidal anti-inflammatory drugs (data on the newer antiplatelet agents are insufficient at present) do not need to be discontinued prior to polypectomy, it would seem sensible to stop these drugs electively for 7 days before any planned resection of large polyps, or when multiple polypectomies are to be performed. In our experience, large sessile adenomas appear to be at particular risk for postpolypectomy bleeding, which can be immediate or delayed 25. We therefore routinely stop aspirin and other antiplatelet drugs for 1 week before a planned piecemeal resection, and patients are kept off these drugs for 2 weeks thereafter. Thirdly, good diathermy technique should always be used, with tissue heating aimed at coagulating vessels without causing excessive tissue destruction. Finally, when large stalked lesions are encountered, some form of haemostatic treatment additional to standard diathermy should be used. Epinephrine injection or an Endoloop are both good options to prevent immediate bleeding. If access to the polyp is easy, then the Endoloop would be the authors’ choice, but when application of the loop proves technically difficult, epinephrine injection is usually quick and easy to perform. Neither of these methods appears to be entirely effective in preventing delayed bleeding (as shown in this study), and additional treatment of the stalk should therefore be considered. Applying Endoclips above the Endoloop or around the point of the epinephrine injection would seem a wise precaution.

References

• 1 Di Giorgio P, De Luca L, Calcagno G. et al . Detachable snare versus epinephrine stalk injection in the prevention of postpolypectomy bleeding: a controlled randomized study.  Endoscopy. 2004;  36 862-865
• 2 Cappell M S, Abdullah M. Management of gastrointestinal bleeding induced by gastrointestinal endoscopy.  Gastroenterol Clin North Am. 2000;  29 125-167
• 3 Rex D K, Lewis B S, Waye J D. Colonoscopy and endoscopic therapy for delayed post-polypectomy hemorrhage.  Gastrointest Endosc. 1992;  38 127-129
• 4 Vernava A M III, Longo W E. Complications of endoscopic polypectomy.  Surg Oncol Clin N Am. 1996;  5 663-673
• 5 Van Gossum A, Cozzoli A, Adler M. et al . Colonoscopic snare polypectomy: analysis of 1485 resections comparing two types of current.  Gastrointest Endosc. 1992;  38 472-475
• 6 Singaram C, Torbey C F, Jacoby R F. Delayed postpolypectomy bleeding.  Am J Gastroenterol. 1995;  90 146-147
• 7 Parra-Blanco A, Kaminaga N, Kojima T. et al . Colonoscopic polypectomy with cutting current: is it safe?.  Gastrointest Endosc. 2000;  51 676-681
• 8 Gibbs D, Opelka F G, Beck D E. et al . Postpolypectomy colonic hemorrhage.  Dis Colon Rectum. 1996;  39 806-810
• 9 Ahmad N A, Kochman M L, Long W B. et al . Efficacy, safety, and clinical outcomes of endoscopic mucosal resection: a study of 101 cases.  Gastrointest Endosc. 2002;  55 390-396
• 10 Rosen L, Bub D S, Reed J F III, Nastasee S A. Hemorrhage following colonoscopic polypectomy.  Dis Colon Rectum. 1993;  36 1126-1131
• 11 Macrae F A, Tan K G, Williams C B. Towards safer colonoscopy: a report on the complications of 5000 diagnostic or therapeutic colonoscopies.  Gut. 1983;  24 376-383
• 12 Dobrowolski S, Dobosz M, Babicki A. et al . Prophylactic submucosal saline-adrenaline injection in colonoscopic polypectomy: prospective randomized study.  Surg Endosc. 2004;  18 990-993
• 13 Williams C B, Waye J D. Colonoscopy and flexible sigmoidoscopy. In: Yamada T, Alpers D, Owyang C (eds) Textbook of gastroenterology. Philadelphia; Lippincott, 2nd ed 1995: 2571-2589
• 14 Weston A P, Campbell D R. Diminutive colonic polyps: histopathology, spatial distribution, concomitant significant lesions, and treatment complications.  Am J Gastroenterol. 1995;  90 24-28
• 15 Hui A J, Wong R M, Ching J Y. et al . Risk of colonoscopic polypectomy bleeding with anticoagulants and antiplatelet agents: analysis of 1657 cases.  Gastrointest Endosc. 2004;  59 44-48
• 16 Nakajima H, Takami H, Yamagata K. et al . Aspirin effects on colonic mucosal bleeding: implications for colonic biopsy and polypectomy.  Dis Colon Rectum. 1997;  40 1484-1488
• 17 Pontecorvo C, Pesce G. The ”safety snare”: a ligature-placing snare to prevent haemorrhage after transection of large pedunculated polyps.  Endoscopy. 1986;  18 55-56
• 18 Hachisu T. A new detachable snare for hemostasis in the removal of large polyps or other elevated lesions.  Surg Endosc. 1991;  5 70-74
• 19 Rey J F, Marek T A. Endo-loop in the prevention of the post-polypectomy bleeding: preliminary results.  Gastrointest Endosc. 1997;  46 387-389
• 20 Iishi H, Tatsuta M, Kitamura S. et al . Endoscopic resection of large sessile colorectal polyps using a submucosal saline injection technique.  Hepatogastroenterology. 1997;  44 698-702
• 21 Folwaczny C, Heldwein W, Obermaier G, Schindlbeck N. Influence of prophylactic local administration of epinephrine on bleeding complications after polypectomy.  Endoscopy. 1997;  29 31-33
• 22 Iishi H, Tatsuta M, Narahara H. et al . Endoscopic resection of large pedunculated colorectal polyps using a detachable snare.  Gastrointest Endosc. 1996;  44 594-597
• 23 Brandimarte G, Tursi A. Endoscopic snare excision of large pedunculated colorectal polyps: a new, safe, and effective technique.  Endoscopy. 2001;  33 854-857
• 24 Eisen G M, Baron T H, Dominitz J A. et al . Guideline on the management of anticoagulation and antiplatelet therapy for endoscopic procedures. American Society for Gastrointestinal Endoscopy.  Gastrointest Endosc. 2002;  55 775-779
• 25 Brooker J C, Saunders B P, Shah S G. et al . Treatment with argon plasma coagulation reduces recurrence after piecemeal resection of large sessile colonic polyps: a randomized trial and recommendations.  Gastrointest Endosc. 2002;  55 371-375