Alvear, S (Alvear, Sandra); Rodriguez, P (Rodriguez, Patricia).Univ Talca, Fac Ciencias Empresariales, Talca, ChileReal daily costs of patients admitted to public intensive care units Background: Patient care costs in intensive care units are high and should be considered in medical decision making. Aim: To calculate the real disease related costs for patients admitted to intensive care units of public hospitals. Material and Methods: Using an activity associated costs analysis, the expenses of 716 patients with a mean age of 56 years, mean APACHE score of 20 (56% males), admitted to intensive care units of two regional public hospitals, were calculated. Patients were classified according to their underlying disease. Results: The costs per day of hospital stay, in Chilean pesos, were $ 426,265 for sepsis, $ 423,300 for cardiovascular diseases, $ 418,329 for kidney diseases, $ 404,873 for trauma, $ 398,913 for respiratory diseases, $ 379,455 for digestive diseases and $ 371,801 for neurologic disease. Human resources and medications determined up to 85 and 12% of costs, respectively. Patients with sepsis and trauma use 32 and 19% of intensive care unit resources, respectively. Twenty seven percent of resources are invested in patients that eventually died. Conclusions: A real cost benefit analysis should be performed to optimize resource allocation in intensive care units. (Rev Med Chile 2013; 141: 202-208).