Simplified therapeutic intervention scoring system (TISS 28) to assess intensive care unit (ICU) costs and the efficiency of the admission process to a medical ICU

Background

Besides evaluation of the severity of illness, quantification of nursing workload, and ICU cost evaluation, TISS has also been proposed a valuable tool analysing the utilisation of ICU facilities. Purpose of this study was to assess the efficiency of the ICU admission process of a medical ICU of a tertiary care centre.

Methods

Over a period of 3 months TISS 28 [1] was prospectively determined for all patients staying > 24 hours in the ICU. According to Knaus et al [2] TISS 28 items were categorised as active (AT) or non-active (NAT) treatment variables. Related costs were calculated using a modified 'top down' method.

Results

303 patients with a hospital mortality of 14.5% were included in the study. Overall 241 patients (79.5%), including all non-survivors, received AT during their ICU stay. ICU and hospital mortality, ICU LOS, costs, admission diagnosis, and source of admission were different in AT vs NAT patients (P < 0.05).

Conclusion

Since ICUs consume a large proportion of hospital budgets for a minority of patients admission should be limited to those depending on these facilities. Categorisation into AT and NAT using TISS 28 may well serve to identify these patients. Our data suggest superfluous ICU admission in 20% of all patients staying longer than 24 hours in the index ICU. Identification and careful analysis of this patients might help to optimise ICU admission and discharge processes and thus improve resource utilisation among ICU, intermediate care unit, and ward in the future.