Long term trends in medical emergency team activations and outcomes.
OBJECTIVE
. To analyze long-term medical emergency team (MET) operational trends including number of MET calls, trigger criteria for activation and clinical outcomes at a tertiary level, university hospital with a mature MET system.


METHODS
The characteristics of 19,030 MET calls between 2000 and 2012 were analyzed in a single-centre, retrospective observational study. Rates indexed per 1000 hospital admissions for MET calls, cardiac arrests, unplanned admissions to the intensive care unit (ICU) and hospital mortality were used as performance measures of the MET. Descriptive statistics (mean±standard deviation) were applied and trends analyzed by one-way ANOVA with year 2000 set as the baseline using Dunn's correction for multiple comparisons, p<0.05.


RESULTS
Activations of the MET increased between 2000 and 2012 (19±3-30±4) and there were changes in reasons for activations over time. Clinical concern (worried) was the most common (22%) trigger criterion in 2000 followed by hypotension (21%) and decreased level of consciousness (17%). In 2012, hypotension was the most common trigger (32%), followed by decreased level of consciousness (19%) and clinical concern (15%). Rates of cardiorespiratory arrest (1.4±0.7-1.1±0.4) and unplanned ICU admission (5.0±1.2-5.9±1.0) did not change between 2000 and 2012. Hospital mortality decreased from 2005 onwards (15±3.4-12±2.2).


CONCLUSIONS
MET activity progressively increased during the study period and there was a change in pattern of specific triggering criteria. The sustained decrease in hospital mortality independent of cardiac arrest and unplanned ICU admissions rates suggests patient benefit from the MET system.
Intensive Care Unit, Royal Lancaster Infirmary, University Hospitals of Morecambe Bay NHS Trust, Ashton Road, Lancaster LA1 4RP, UK.
Ruth
R
Herod
Intensive Care Unit, Liverpool Hospital, Sydney South West Local Health District, Elizabeth Street, Liverpool, NSW 2170, Australia; University of Western Sydney, Penrith, NSW 2751, Australia.
Steven A
SA
Frost
Intensive Care Unit, Liverpool Hospital, Sydney South West Local Health District, Elizabeth Street, Liverpool, NSW 2170, Australia; University of New South Wales, South Western Sydney Clinical School, Elizabeth Street, Liverpool, NSW 2170, Australia.
Michael
M
Parr
Intensive Care Unit, Liverpool Hospital, Sydney South West Local Health District, Elizabeth Street, Liverpool, NSW 2170, Australia; University of New South Wales, South Western Sydney Clinical School, Elizabeth Street, Liverpool, NSW 2170, Australia; Simpson Centre for Health Services Research, Australian Institute of Health Innovation, University of New South Wales, Botany Street, Randwick, NSW 2031, Australia.
Ken
K
Hillman
Intensive Care Unit, Liverpool Hospital, Sydney South West Local Health District, Elizabeth Street, Liverpool, NSW 2170, Australia; University of New South Wales, South Western Sydney Clinical School, Elizabeth Street, Liverpool, NSW 2170, Australia. Electronic address: anders.aneman@swsahs.nsw.gov.au.
Anders
A
Aneman
D000368:Aged; D004630:Emergencies; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000628:therapy*; D057209:Hospital Rapid Response Team / Q000639:trends*; D006801:Humans; D007362:Intensive Care Units / Q000458:organization & administration*; D008297:Male; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D013997:Time Factors
Cohort studies; Medical emergency team; Organization and administration; Rapid response system