Intensive Care Medicine

, Volume 42, Issue 6, pp 987–994 | Cite as

Effect of ICU strain on timing of limitations in life-sustaining therapy and on death

  • May Hua
  • Scott D. Halpern
  • Nicole B. Gabler
  • Hannah Wunsch



The effect of capacity strain in an ICU on the timing of end-of-life decision-making is unknown. We sought to determine how changes in strain impact timing of new do-not-resuscitate (DNR) orders and of death.


Retrospective cohort study of 9891 patients dying in the hospital following an ICU stay ≥72 h in Project IMPACT, 2001–2008. We examined the effect of ICU capacity strain (measured by standardized census, proportion of new admissions, and average patient acuity) on time to initiation of DNR orders and time to death for all ICU decedents using fixed-effects linear regression.


Increases in strain were associated with shorter time to DNR for patients with limitations in therapy (predicted time to DNR 6.11 days for highest versus 7.70 days for lowest quintile of acuity, p = 0.02; 6.50 days for highest versus 7.77 days for lowest quintile of admissions, p < 0.001), and shorter time to death (predicted time to death 7.64 days for highest versus 9.05 days for lowest quintile of admissions, p < 0.001; 8.28 days for highest versus 9.06 days for lowest quintile of census, only in closed ICUs, p = 0.006). Time to DNR order significantly mediated relationships between acuity and admissions and time to death, explaining the entire effect of acuity, and 65 % of the effect of admissions. There was no association between strain and time to death for decedents without a limitation in therapy.


Strains in ICU capacity are associated with end-of-life decision-making, with shorter times to placement of DNR orders and death for patients admitted during high-strain days.


End-of-life care Palliative care Decision-making Critical care 



Dr. Hua is supported by a Mentored-Training Research Grant from the Foundation in Anesthesia Education and Research. Dr. Halpern is supported by a grant from The Otto Haas Charitable Trust. Nicole B. Gabler: None. Dr. Wunsch is supported by Award Number K08AG038477 from the National Institute On Aging.

Compliance with ethical standards

Conflicts of interest

The authors declare that they have no conflict of interest. The funding sources played no role in the design and conduct of the study, collection, management, analysis, and interpretation of the data, or preparation, review, or approval of the manuscript.

Supplementary material

134_2016_4240_MOESM1_ESM.doc (252 kb)
Supplementary material 1 (DOC 253 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg and ESICM 2016

Authors and Affiliations

  • May Hua
    • 1
  • Scott D. Halpern
    • 2
    • 3
    • 4
    • 5
    • 6
  • Nicole B. Gabler
    • 4
    • 5
  • Hannah Wunsch
    • 7
    • 8
    • 9
  1. 1.Department of AnesthesiologyColumbia University College of Physicians and SurgeonsNew YorkUSA
  2. 2.Division of Pulmonary, Allergy and Critical Care MedicinePerelman School of Medicine at the University of PennsylvaniaPhiladelphiaUSA
  3. 3.Leonard Davis Institute of Health EconomicsUniversity of PennsylvaniaPhiladelphiaUSA
  4. 4.Center for Clinical Epidemiology and BiostatisticsPerelman School of Medicine at the University of PennsylvaniaPhiladelphiaUSA
  5. 5.Fostering Improvement in End-of-Life Decision Science (FIELDS) ProgramUniversity of PennsylvaniaPhiladelphiaUSA
  6. 6.Department of Medical Ethics and Health PolicyPerelman School of Medicine at the University of PennsylvaniaPhiladelphiaUSA
  7. 7.Department of Critical Care MedicineSunnybrook Health Sciences CenterTorontoCanada
  8. 8.Department of Anesthesia and Interdisciplinary Department of Critical Care MedicineUniversity of TorontoTorontoCanada
  9. 9.Department of AnesthesiologyColumbia University College of Physicians and SurgeonsNew YorkUSA

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