Topical hemostatic agents: a systematic review with particular emphasis on endoscopic application in GI bleeding.

C O GI bleeding (GIB) remains a major cause of morbidity and mortality worldwide. Endoscopic management of GIB could be challenging, despite the existing advancements in hemostatic techniques; there are unmet needs for the introduction of topical hemostatic agents in management of profound venous or arterial GIB and malignant lesions with a large surface area that are not quite amenable to traditional endoscopic hemostatic techniques. Many topical hemostatic agents have been developed over the past 50 years with widespread medical applications.1 The inroduction of topical hemostatic agents in the modern urgical era can be traced back to 1909, when Bergel first iscussed the use of topical fibrin for hemostasis. This lass of preparations, known as fibrin sealants, marked the eginning of wide spectrum of topical hemostatic agents ith various mechanisms of action. Gelatin-based hemostatic agents2 and cyanoacrylate adhesives3 were 2 more common topical hemostatic agents introduced in the 1940s.1 In the 1970s, a new class of gents, namely, microfibrillar collagen products, were synhesized by purifying and processing bovine collagen4; these were then manipulated to different hemostatic agents that were used in various surgical specialties for achieving hemostasis. In 1998, the U.S. Food and Drug Administration approved Tisseel, the first commercial fibrin sealant. These compounds were used as surgical hemostatic and adhesive material.5 Other topical hemotatic agents, including topical thrombin,6 endoscopic pray of clotting factors,7 and topical sucralfate,8 have een introduced in limited clinical data with various outomes. More recently, additional agents have been dapted to digestive endoscopy and the management of IB. We review the mechanisms of action of powderased topical hemostatic agents and their efficacy and