Which among the following is useful in upper GI bleeding evaluation

Ans) a (Endoscopy)Ref: Sabiston's textbook of surgery 18th editionUpper GI bleeding refers to bleeding that arises from the GI tract proximal to the ligament of Treitz and accounts for nearly 80% of significant GI hemorrhage. The causes of upper GI bleeding are best categorized as either nonvariceal or bleeding related to portal hypertension. The nonvariceal causes account for about 80% of such bleeding, with peptic ulcer disease being the most .common.The foundation of diagnosis and management of patients with an upper GI bleed is an OGD scopy. Early OGD scopy (within 24 hours) results in reductions in blood transfusion requirements, a decrease in the need for surgery, and a shorter length of hospital stay. Endoscopic identification of the source of bleeding also permits an estimate of the risk for subsequent or persistent hemorrhage as well as facilitating operative planning.