Evaluating the impact of implementing an early warning score system on incidence of in-hospital cardiac arrest.
OBJECTIVE
To evaluate the introduction of an early warning score (EWS) system on incidence of in-hospital adult cardiac arrest.


METHODS
A before-after evaluation of an EWS system (in the form of a patient observation chart with escalation protocol) in a 600 bed tertiary teaching hospital in New Zealand during the two 12-month periods between March 2009 and March 2011. Difference in incidence rates was compared using Student's t test.


RESULTS
There were 168 cardiac arrests during the 24 month period. The incidence rate of cardiac arrests per 1000 admissions was 4.67 during 2009-2010 and 2.91 during 2010-2011 (mean difference of 1.77, 95%CI 0.59-2.94). The number of cardiac arrests dropped from an average of 8.5 arrests per month during 2009-2010 to 5.5 arrests per month during 2010-2011 following the introduction of ADDS (mean difference 3.0, 95%CI 0.78-5.22). There was no significant increase in the number of medical emergency calls (7.5 calls versus 9.1 calls per month).


CONCLUSIONS
Introduction of an EWS system in addition to an existing cardiac arrest team response decreased the incidence of in-hospital cardiac arrests in a tertiary hospital in New Zealand.
Rapid Response System Project, Waikato District Health Board, Hamilton, New Zealand. drowerd@gmail.com.
David
D
Drower
Renee
R
McKeany
Pranesh
P
Jogia
Andrew
A
Jull
D006323:Heart Arrest / Q000453:epidemiology*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D009520:New Zealand; D010348:Patient Care Team; D012042:Registries; D018570:Risk Assessment / Q000379:methods*; D017180:Tachycardia, Ventricular / Q000453:epidemiology; D014693:Ventricular Fibrillation / Q000453:epidemiology