Evaluation of nasogastric tubes to enable differentiation between upper and lower gastrointestinal bleeding in unselected patients with melena.

Gastrointestinal (GI) bleeding is a common surgical problem. The aim of this study was to evaluate how insertion of the nasogastric tube may enable differentiation between upper and lower GI bleeding in patients with melena. A retrospective study involving patients admitted to our surgery division with a melena was carried out between the years 2010 and 2012.