This was an observational study and no attempt was made to influence decisions to admit or not admit patients to ICU. Patients were referred to ICU by doctors in the emergency department, medical ward, surgical ward or operating selleck chemicals Palbociclib room. Patients were excluded if they were referred to ICU for consultation only or from other ICUs as well as intermediate (high dependency) units in the same hospital. For patients with more than one ICU triage during the same hospital stay, only the first triage was considered in the present analyses.Effect of ICU admission on patient mortalityThe effectiveness of ICU admission was evaluated by comparing the 28-day mortality for patients accepted in ICU with that of patients not accepted and treated in the ward. Three-month mortality was also evaluated as a secondary outcome.

Although hospital mortality was also available, we did not use this outcome measure since this varies widely across centres and countries as a result of different policies for hospital discharge.The case mix of patients accepted in ICU is likely to differ in terms of severity and prognosis from that of patients refused, and, therefore, analyses were adjusted for possible confounders.Possible confounding variables were selected through backward stepwise procedure, and included; age; Karnofsky performance status (a marker of chronic health); and indication for referral to ICU (treatment or observation). Since the observed effect on mortality of ICU admission varied with the severity of illness (as measured by SAPS II), the analyses were stratified by categories of predicted mortality, calculated from the SAPS II score [11].

CostsCost of ICU admission was evaluated by comparing the total hospital cost per patient for patients accepted to the ICU against the total cost for patients not accepted and treated on the ward. For patients accepted to ICU, the total cost was defined as the cost of the ICU stay, plus the ward stay cost after ICU discharge. The daily cost per patient for both ICU and ward was calculated for each participating hospital using a top-down approach, based on the cost-block method [1]. Although this approach has been developed for use in the ICU, it has also been used to calculate ward costs for consistency and in the absence of any other accepted method [12]. The cost-block method derives an average daily cost per patient from the total annual cost of the unit.

The total annual cost is estimated as the sum of the main cost determinants, or “cost-blocks”, which include; consumables (drugs, nutritional products, blood products and disposables); clinical support services defined as services essential to the ICU but not provided within the ICU (laboratory, radiology and physiotherapy); and ICU staff (doctors, junior and Entinostat senior, and nurses).