Background. The aim of this retrospective analysis was the evaluation of the effect of parenteral nutrition before surgery in malnourished patients on the reduction of risks during postoperative period after upper gastrointestinal tract resection. 57 patients with the diagnosis of oesophageal or stomach carcinoma were included into the selected group. Patients were divided into three groups: I. group: resecabile tumor, parenteral nutrition, malnutrition, II. group: nonresecabile tumor, parenteral nutrition, malnutrition, III. group: resecabile tumor, without parenteral nutrition, well nourished. Methods and Results. In the group of malnourished patients, seven days after the applied parental nutrition, a statistical significant difference in the elevated values of proteins (I.: 62 ± 3.8→70 ± 1.75, II.: 59.7 ± 3.2→69.2 ± 1.2) and albumin (I: 32.6 ± 1.95→38.0 ± 1.09, II.: 31.1 ± 1.2→37.5 ± 0.9) p < 0.001 were achieved. Complications associated with the insertion of central venous catheter decreased as follows: plugged catheter (17.6%), local erythema (7.5%), pneumothorax (5%), phlebotrombosis (5%), haemothorax (0.4%). Postoperative complications did not achieve statistical significance (p < 0,05) in the groups I.–III. The highest incidence of wound and anastomosis dehiscention and sepsis was noticed in the first group, the lowest in the third group. Brochopneumonia had the highest occurrence in the second group, the lowest in the third group. Conclusions. Preoperative parenteral nutrition as a prevention of complications after resection surgery on stomach and oesophagus is beneficial in the middle and high grade of malnourished patients, despite of higher costs and prolonged hospitalization, considering the comparable percentage of postoperative complications in the group of non-malnourished and malnourished patients. The nutritional supplementation should take at least seven days.

        Key words: parenteral nutrition, preoperative preparation, malnutrition, carcinoma of upper gastrointestinal tract.