Research
Risk factors for acute organ failure in intensive care unit patients who receive respiratory support in the absence of non-respiratory organ failure: an international prospective cohort study
1 Division of Asthma, Allergy Lung Biology, School of Medicine, King's College London, St Thomas Street, London, SE1 9RT, UK
2 Critical Care & Anaesthesia Research Group, King's Health Partners Academic Health Sciences Centre, Westminster Bridge Road, London, SE1 7EH, UK
3 Department of Critical Care Medicine, Guy's and St. Thomas' NHS Foundation Trust, Westminster Bridge Road, London, SE1 7EH, UK
4 Intensive Care Unit, Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane, QLD 4102, Australia
5 Department of Anaesthesia and Critical Care, School of Medicine, The University of Queensland, 288 Herston Road, Brisbane, QLD 4006, Australia
6 Intensive Care Unit, Altnagelvin Hospital, Glenshane Road, Derry, BT47 6SB, Northern Ireland
7 Interdepartmental Division of Critical Care Medicine, University of Toronto, 200 Elizabeth St., Toronto, ON, M5S 1A8, Canada
8 School of Medicine, Queen Mary University, Mile End Road, London, E1 4NS, UK
9 Department of Critical Care Medicine, The Royal London Hospital, Whitechapel Road, London, E1 1BB, UK
10 Department of Critical Care Medicine, St. George's Healthcare NHS Trust, Blackshaw Road, London, SW17 0QT, UK
11 Centre for Perioperative Medicine and Critical Care Research, Imperial College Healthcare NHS Trust, Du Cane Road, London, W12 0HS, UK
12 Centre for Infection and Immunity, Queen's University Belfast, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland
13 Regional Intensive Care Unit, Royal Victoria Hospital, Lisburn Road, Belfast, BT9 7AB, Northern Ireland
Critical Care 2012, 16:R61 doi:10.1186/cc11306
Published: 18 April 2012Abstract
Introduction
Many supposed low-risk intensive care unit (ICU) admissions develop acute organ failure (AOF). Identifying patients at high risk of developing AOF and targeting them with preventative strategies may be effective. Our study question was: in a population of ICU patients receiving positive pressure respiratory support (invasive or non-invasive) in the absence of non-respiratory AOF, what is the 14-day incidence of, risk factors for and time to acute organ failure?
Methods
In an international prospective cohort study, patients receiving positive pressure respiratory support (invasive or non-invasive) in the absence of non-respiratory AOF were enrolled and followed for 14 days. The primary outcome measure was the incidence of any AOF (defined as SOFA 3 to 4) during follow-up.
Results
A total of 123 of 766 screened patients (16.1%) were enrolled. Data are reported for 121 patients. In total, 45 out of 121 patients (37.2%) developed AOF. Mortality rates were higher in those with AOF: 17.8% versus 4.0% OR 5.11, P = 0.019) for ICU mortality; and 28.9% versus 11.8% (OR 2.80, P = 0.019) for hospital mortality. Median ICU length of stay was also longer in those with AOF (11 versus 3.0 days; P < 0.0001). Hypoxemic respiratory failure (P = 0.001) and cardiovascular dysfunction (that is, SOFA 1 to 2; P = 0.03) were associated with AOF. The median time to first AOF was two days.
Conclusions
Patients receiving positive (invasive or non-invasive) pressure respiratory support in the absence of non-respiratory AOF are commonly admitted to ICU; AOF is frequent in these patients. Organ failure developed within a short period after admission. Hypoxemic respiratory failure and cardiovascular dysfunction were strongly associated with AOF.



