Perioperative Assessment of Right Ventricular Function and Venous Return in Patients With Epithelial Ovarian Cancer Undergoing Cytoreductive Surgery (Gyn Right) - Pilot Study

Inclusion Criteria: * Offered patient information and written informed consent * Female patients aged greater than or equal to 18 years for cytoreductive surgery of a primary epithelial ovarian tumour 1. Patient Group 1: Female patients with \> 500 ml ascites in the preoperative sonographic examination 2. Patient group 2: Female patients aged \> 70 years and at least one of the following secondary diagnoses: * Status Post stent placement due to coronary heart disease respectively Status Post-myocardial infarction * existing arterial Hypertension for more than 5 years * chronic heart failure (New York Heart Association (NYHA) class II-III) * peripheral arterial disease Exclusion Criteria: * Patients aged less than 18 years * Persons without the capacity to consent * Inability of German language use * Lacking willingness to save and hand out data within the study * Accommodation in an institution due to an official or judicial order * (Unclear) history of alcohol or substances disabuse * Coworker of the Charité * Advanced disease of the oesophagus or upper respiratory tract at the beginning of hospitalization * Operation in the area of the oesophagus or nasopharynx within the last two months before participation in the study * Neurological or psychiatric disease at the beginning of hospitalization * CHF (congestive heart failure) according to (New York Heart Association) classification - NYHA class IV at the beginning of hospitalization * American Society of Anesthesiologists (ASA) classification greater than IV * Renal insufficiency (dependency of haemodialysis) at the beginning of hospitalization * Pulmonary oedema in thorax x-ray at the beginning of hospitalization * History of intracranial hemorrhage within one year before participation in the study * Conditions following venous thrombosis within the last three years before study inclusion * Known allergies or hypersensitivity on colloidal, starch or gelatine infusion solutions * Diabetes mellitus with signs of severe neuropathy * Known atrial fibrillation * Participation in an interventional clinical trial during the study period; exception: assignment to adjuvant therapy study during this study is allowed.