It is the hypothesis of this project that the Mesenteric Traction Syndrome (MTS) is a common event during upper gastrointestinal cancer surgery (UGC surgery) and that the induction of the syndrome is an important factor in provoking further peri- and postoperative complications and in worsening the surgical stress response (SSR). The characteristics of MTS is hypotension, tachycardia, and flushing.