Institution-free days after critical illness: A multicenter retrospective study

J Crit Care. 2023 Apr:74:154253. doi: 10.1016/j.jcrc.2023.154253. Epub 2023 Jan 12.

Abstract

Background: Patient-centered outcomes beyond mortality such as institution-free days (IFD) are becoming increasingly relevant in critical care trials.

Methods: We calculated IFD using three definitions which differed in the way death and censoring of after-hospital deaths were handled analysing data from adult patient databases admitted to four ICUs of North Brisbane, Australia. Differences in distribution of IFD using different definitions were explored with descriptive statistics and histograms. Six pre-specified variables (age, illness severity, comorbidities index, elective status, surgical/medical admission and treatment limitations) were assessed and reported as determinants of IFDs for the proposed definitions.

Results: Data from 25,371 ICU admissions was analysed. The density distribution of IFD was bimodal with a peak at 0 days and a variable right-sided peak depending on the definition used. The mean IFD varied from 253 (standard deviation(SD) 151.3) to 295 (SD 116.2) depending on definition used. Multivariable zero-inflated negative binomial regression modelling showed that the six pre-specified variables had significant associations with IFD and their magnitude of effect varied with the definition used.

Conclusions: IFD is a simple, easily measurable patient-centered outcome that varies depending on the definition used. Patient input should be sought to define the optimum definition and clinical use of IFD.

Keywords: Critical care; Determinants; Institution-free days; Patient-centred outcomes.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Critical Care
  • Critical Illness*
  • Humans
  • Intensive Care Units*
  • Outcome Assessment, Health Care
  • Retrospective Studies