Resource use in the ICU: short- vs. long-term patients

Background: Intensive care medicine uses a disproportionate share of medical resources, and little is known about the distribution of resources between different patient groups. Methods: In this prospective observational study, all patients admitted between 1 January 1998 and 31 December 1999 to our medical-surgical university's ICU were assigned to one of two groups according to length of stay (LOS): patients staying more than 7 days in the unit (group L) and those staying a maximum of 7 days (group S). Resource use was estimated using TISS-28, number of nursing shifts, use of mechanical ventilation, and use of renal replacement therapy. Further, SAPS II and ICU and hospital mortalities were recorded. Results: Of 5481 patients, 583 (10.6%) were in group L and 4898 in group S (89.4%). Patients in group L were more severely sick upon admission than those in group S. Patients in group L stayed a total of 9726 days in the ICU (52.5% of the total LOS). In group L, 69.2% of all shifts with respiratory support and 80.1% of all shifts with renal replacement were used. Further, group L patients consumed 53.4% (909225) of all TISS points provided. The ICU-mortality rates were 14.4% in group L and 7.2% in group S, and the hospital mortality rates were 19.9% and 9.8%, respectively. A mean of 1898 TISS points was used per patient surviving the hospital stay in group L compared with 190 points in group S. Conclusion: In this university-based, medical-surgical adult ICU, 11% of all patients stayed more than 7 days in the unit and consumed more than 50% of all resources. Thus, a highly disproportionate amount of resources were used per survivor in group L compared with those in group S.