ESTIMATION OF DIRECT COST AND RESOURCE-ALLOCATION IN INTENSIVE-CARE -CORRELATION WITH OMEGA-SYSTEM

Objective:An instrument able to estimate the direct costs of stays in Intensive Care Units (ICUs) simply would be very useful for resource a llocation inside a hospital, through a global budget system. The aim o f this study was to propose such a tool. Design: Since 1991, a region- wide common data base has collected standard data of intensive care su ch as the Omega Score, Simplified Acute Physiologic Score: length of s tay, length of ventilation, main diagnosis and procedures. The Omega S core, developed in France in 1986 and proved to be related to the work load, was recorded on each patient of the study Setting: Eighteen ICUs of Assistance Publique-Hopitaux de Paris (AP-HP) and suburbs. Patient s: 1) Hundred twenty-one randomly selected ICU patients, 2) 12,000 con secutive ICU stays collected in the common data base in 1993. Measurem ents: 1) On the sample of 121 patients. medical expenditure and nursin g lime associated with interventions were measured through a prospecti ve study. The correlation between Omega points and direct costs was ca lculated, and regression equations were applied to the 12,000 stays of the data base, leading to estimated costs. 2) From the analytic accou nting of AP-HP, the mean direct cost per stay and per unit was calcula ted, and compared with the mean associated Omega score from the data b ase. In both methods a comparison of actual and estimated costs was ma de. Results: The Omega Score is strongly correlated to total direct co sts, medical direct costs and nursing requirements. This correlation i s observed both in the random sample of 121 stays and on the data base ' stays. The discrepancy of estimated costs through Omega Score and ac tual costs may result from drugs: blood product underestimation and th erapeutic procedures not involved in the Omega Score. Conclusions: The Omega system appears to be a simple and relevant indicator with which to estimate the direct costs of each stay, and then to organise nursi ng requirements and resource allocation.