[A new model for economic studies of therapies exemplified by postoperative parenteral nutrition].

In this economic evaluation we compared the costs of a new therapeutic system (two-chamber bag) in total parenteral nutrition (TPN) with the comparative standard therapeutic systems (multiple-bottle system in intensive care patients followed by a combination solution (glass bottles) on the ward). In the model, standard treatment algorithms of a 10-day course TPN for patients after major gastric surgery were specified for both application systems, the two-chamber bag and the comparative system. Based on the standard treatment pattern, the resource utilisation (manpower services, medical needs, material) was assessed. In a base case analysis the types and amounts of resources were valued using salaries, prices and tariffs to assess the costs. The costs per day and per case of the therapeutic systems were compared. Sensitivity analyses were carried out to validate the cost-estimates. The total costs per patient of the two-chamber bag amounted to DM 2324.41, which was substantially less than the DM 2728.99 cost of the comparative system. The average daily costs for the two-chamber bag system were 12% to 23% lower than for the comparative system. The results were shown to be valid for the whole range of tested parameters. This model makes it possible to obtain an economic evaluation of various therapeutic modalities without undertaking a prospective randomized study with the attendant high time and cost requirements.