Exploring unplanned ICU admissions: a systematic review.
BACKGROUND
Adverse events are unintended patient injuries or complications that arise from healthcare management resulting in death, disability or prolonged hospital stay. Adverse events that require critical care are a considerable financial burden to the healthcare system. Medical record review seems to be a reliable method for detecting adverse events.


OBJECTIVE
To synthesize the best available evidence regarding the estimates of the incidence and preventability of adverse events that necessitate intensive care admission; to determine the type and consequences (patient harm, mortality, length of ICU stay and direct medical costs) of these adverse events.


METHODS
MEDLINE (from 1966 to present), EMBASE (from 1974 to present) and CENTRAL (version 1-2010) were searched for studies reporting on unplanned admissions to intensive care units (ICUs). Databases of reports, conference proceedings, grey literature, ongoing research, relevant patient safety organizations and two journals were searched for additional studies. Reference lists of retrieved papers were searched and authors were contacted in an attempt to find any further published or unpublished work. Only quantitative studies that used chart review for the detection of adverse events requiring intensive care admission were considered for eligibility. Studies that were published in the English, Dutch, German, French or Spanish language were included. Two reviewers independently extracted data and assessed the methodological quality of the included studies.


RESULTS
28 studies in the English language and one study in French were included. Of these, two were considered duplicate publications and therefore 27 studies were reviewed. Meta-analysis of the data was not appropriate due to statistical heterogeneity between studies; therefore, results are presented in a descriptive way. Studies were categorized according to the population and the providers of care. 1) The majority of the included studies investigated unplanned intensive care admissions after anesthetic procedures (UIA). 2) Only a few studies examined patients on general wards being at risk for clinical deterioration. The overall incidence of surgical and medical adverse events compared with ICU admissions ranged from 1.1% to 37.2%. 3) The third category of studies examined patients that were readmitted on ICUs. ICU readmission rates varied from 0% to 18.3%. Nine studies explicitly reported on the preventability of adverse outcomes. The preventability rates of the adverse events varied from 17% to 76.5%. Preventable adverse events are further synthesized by type of event and patterns of preventability are being formulated. Consequences of the adverse events included a mean length of ICU stay that ranged from 1.5 days to 10.4 days for the patient's first stay in ICU. Mortality rates varied between 0% and 58%.


CONCLUSIONS
Adverse events are a persistent and an important reason for admission to the ICU. However, there is relatively weak evidence to estimate an overall incidence and preventability rate of these events. In addition, estimates on preventability are prone to subjective judgments. Variability in methodology and definitions, and poor reporting in studies may be the main reasons for study heterogeneity.


CONCLUSIONS
Unplanned intensive care admission within 24 hours of a procedure with an anesthetist in attendance (UIA) is a recommended clinical indicator in surgical patients. Several authors recommend early detection of patients with clinical instability on general wards and the implementation of rapid response teams. Step-down or intermediate care units could be a useful strategy for patients that require monitoring to avoid ICU readmissions.


CONCLUSIONS
There is a need for further studies on the detection of adverse events. The poor quality of current research evidence and the heterogeneity across studies requires that planning of future studies should aim to standardize measures of outcomes to allow for comparisons across studies. This area of research is important in order to identify and explain failure of healthcare systems leading to patient harm, with the ultimate aim to improve the quality and safety of care.
1. Researcher, Hasselt University, Faculty of Medicine, Diepenbeek, Belgium 2. Intensivist, Emergency Department, Katholieke Universiteit Leuven, Leuven, Belgium 3. Researcher, Belgian Interuniversity Collaboration for Evidence-Based Practice (BICEP), Belgian Center for Evidence Based Medicine, Katholieke Universiteit Leuven, Leuven, Belgium 4. Professor, Hasselt University, Faculty of Medicine, Diepenbeek, Belgium 5. Delegate Director, ICURO, Brussels, Belgium.
Annemie
A
Vlayen
Sandra
S
Verelst
Geertruida E
GE
Bekkering
Ward
W
Schrooten
Johan
J
Hellings
Nerée
N
Claes