Plasma Volume Replacement (PVR) Therapy With Colloid and Crystalloid Solutions

Inclusion: * patients scheduled to undergo elective surgery of the pancreatic head * patients who are willing to give of voluntary consent to participate in the study, following a full explanation of the nature and purpose of the study, by signing the informed consent form approved by the Institutional Ethics Committee (IEC) prior to all evaluations. Exclusion: * patients of American Society of Anesthesiologists (ASA) class \> III * heart failure defined as New York Heart Association (NYHA) class\>2 * aneurysm of the ascending and thoracic aorta * patients with Zenker's diverticle * local oesophageal disease (oesophageal stricture, oesophageal varices, previous oesophageal surgery in past 6 months before study inclusion, pharyngeal pouch) * patients receiving haemodialysis * patients with known bleeding diatheses * any bleeding disorder known from patient's history * patients with a haematocrit \<= 25% despite pre-operative transfusion * renal insufficiency (serum creatinine \> 130 µmol/l or \>1.5 mg/dl) or oliguria or anuria * impaired hepatic function defined as Mayo End-Stage Liver Disease (MELD) \> 10 or liver cirrhosis Child-Pugh B or C * additional contra-indications for investigational products