Does space make waste? The influence of ICU bed capacity on admission decisions

Esteban Mery, Jeremy M Kahn

EXPANDED ABSTRACT: CITATION: Stelfox HT, Hemmelgarn BR, Bagshaw SM, Gao S, Doig CJ, Nijssen-Jordan C, Manns B: Intensive care unit bed availability and outcomes for hospitalized patients with sudden clinical deterioration. Arch Intern Med 2012, 172:467-474. BACKGROUND: Intensive care unit (ICU) beds are a scarce resource, and admissions may require prioritization when demand exceeds supply. However, there are few empiric data on whether the availability of ICU beds influences triage and processes of care for hospitalized patients who develop sudden clinical deterioration. METHODS: OBJECTIVE: The objective was to evaluate the effect of ICU bed availability on the processes and outcomes of care for hospitalized patients with sudden clinical deterioration on a hospital ward. DESIGN: We conducted a retrospective cohort study. SETTING: The study was conducted in three hospitals in Calgary, Alberta, Canada, with 2,040 beds and a catchment population of 1.5 million individuals. SUBJECTS: Hospitalized adults (n = 3,494) with a sudden clinical deterioration triggering medical emergency team (MET) activation between 1 January 2007 and 31 December 2009 participated. ANALYSIS: This study compared treatments and outcomes among sudden clinical deterioration patients according to the number of ICU beds available (zero, one, two, or more than two) at the time of the MET activation. The outcomes of interest were ICU admission rates (within 2 hours of MET activation), changes in the goals of care (resuscitative, medical, and comfort), and hospital mortality. All analyses were adjusted for hospital, physician, and patient factors. RESULTS: The cohort consisted of 3,494 patients. Reduced ICU bed availability was associated with a decreased likelihood of ICU admission within 2 hours of MET activation (P = 0.03) and with an increased likelihood of change in patient goals of care (P <0.01). Patients with sudden clinical deterioration when zero ICU beds were available were 33.0% (95% confidence interval (CI), -5.1% to57.3%) less likely to be admitted to the ICU and were 89.6% (95% CI, 24.9% to 188.0%) more likely to have their goals of care changed compared with when more than two ICU beds were available. However, hospital mortality did not vary significantly by ICU bed availability (P = 0.82). CONCLUSIONS: For hospitalized patients with sudden clinical deterioration, ICU bed scarcity decreases the probability of ICU admission and increases the probability of initiating comfort measures on the ward but does not influence hospital mortality.