State-wide reduction in in-hospital cardiac complications in association with the introduction of a national standard for recognising deteriorating patients

Abstract

Aim: To examine whether introducing a national standard to improve the recognition of and response to clinical deterioration, was associated with a reduction in cardiovascular events in the hospital environment.

Method: Interrupted time series was used to analyse the trajectories of monthly complication rates for 4.69 million admissions in 218 hospitals. Trajectory slopes determined for the "baseline period" (1 July 2007-30 June 2010) and the "Intervention period" (1 January 2013-30 June 2014) were compared (slope ratio).

Results: Before the intervention, complication rates due to arrhythmias were increasing, acute coronary syndrome (ACS) and all-cause mortality decreasing, but were constant for cardiac arrest and heart failure and pulmonary oedema. Analysis of the overall data suggested reduction in the rate of cardiac and ACS complications after the intervention, but no significant change in overall hospital mortality. Analysis by age category showed significant reductions in monthly rate trajectories in the 80 plus years age group for cardiac arrest (slope ratio 0.983, 95% CI: 0.972-0.994) and ACS (0.989, 95% CI: 0.981-0.997) complications. Slope ratios indicating reduced monthly rates were seen in females for cardiac arrest (0.985, 95% CI: 0.977-0.994), ACS (0.991, 95% CI: 0.984-0.998) and heart failure (0.993, 95% CI: 0.986-1.000) complications. There were also significant reductions in cardiac arrest (0.983, 95% CI: 0.969-0.996), ACS (0.991, 95% CI: 0.982-1.000) and arrhythmia (0.996, 95% CI: 0.994-0.998) complications for surgical patients.

Conclusions: Introduction of a national standard for deteriorating hospitalised patients was associated with a reduction in the rates of in-hospital cardiac arrests and acute coronary syndromes in acute hospitals. Greatest benefit was seen in the elderly, female and surgical patients.

Keywords: Cardiac complications; In-hospital cardiac arrest; National standards; Rapid response system; Rapid response team.