Though the concept behind deployment of Rapid Response Teams (RRT’s) makes good sense, the impact on patient outcomes after deployment of RRT’s has been disappointing to date. We first talked about Rapid Response Teams in our August 2007 What’s New in the Patient Safety World column “Rapid Response Teams Don’t Live Up to Expectations” we discussed the weakness of the evidence supporting a positive effect of rapid response teams on patient outcomes and discussed many of the methodological problems in studies on RRT’s.”. Then, in our November 27, 2007 Patient Safety Tip of the Week “ ” and our December 2008 What’s New in the Patient Safety World column “
Now the researchers (Chen et al 2009) involved in one of the largest prospective randomized trials of RRT’s have reanalyzed the data from the MERIT study (Medical Emergency Response Intervention and Therapy) and found evidence to support the concept of the early emergency call. The MERIT study was a cluster randomized controlled trial in which hospitals in Australia were randomized into 2 groups: those that had rapid response systems and those that did not. That study failed to demonstrate any significant improvement in outcomes between the RRT hospitals and the control ones. However, when they analyzed the data, they noted that almost half the calls to the cardiac arrest teams in control hospitals were “early” calls (i.e. before a cardiac arrest) and that at the RRT hospitals many patients who met the criteria for a call to the RRT never had such a call. They speculated that this “contamination” may have been responsible for the insignificant results in MERIT.
So they reviewed the data, asking the new question “were early calls associated with improved outcomes?”. Indeed, they found that early calls were associated with reductions in the rate of cardiac arrests and unexpected deaths. For every 10% increase in early calls, there was a 2.2 per 100,000 reduction in cardiac arrests and a 0.94 per 100,000 reduction in unexpected deaths. There was no statistical reduction of overall deaths, unplanned ICU admissions, or an aggregate measure of all the outcomes combined.
So the data do support the concept of developing systems to recognize patients who are clinically deteriorating and respond earlier. What is unclear is what “early warning” systems work best and how to best respond.
As we have said before, all the negative evidence on use of RRT’s does not negate the logic of having a culture of safety that helps recognize early patients that are in need of “rescue”. Although it does raise many questions about committing many resources to develop RRT’s without better evidence-based validation of the RRT concept, the idea remains a sound one but the most appropriate targets, the triggers, the makeup of teams, the mode of response, the logistics, and the best outcome measures all need to be validated before hospitals rush willy-nilly into developing RRT’s. The Chen paper would suggest that refining the criteria and system for early recognition may be the best place to start.
In our August 2007 What’s New in the Patient Safety World
care for the acutely ill patient: learning from serious incidents” and NICE
(National Institute for Health and Clinical Excellence) has just released its
clinical guideline “Acutely ill
patients in hospital. Recognition of and response to acute illness in adults in
the hospital”. The NICE guideline discusses several scoring systems for
identification of patients clinically deteriorating, including the MET (single parameter), MEWS (aggregate scoring
system) and ASSIST (assessment score for sick patient identification and
step-up in treatment – aggregate scoring system) systems.
randomized controlled trials may be needed to determine the best method of
responding to critical clinical deterioration of a patient, it remains intuitive
that systems which enhance early identification of such clinical deterioration
are desirable. Joint
Commission’s National Patient Safety Goal requiring a plan to “Improve
recognition and response to changes in a patient’s condition” makes sense
even if a “traditional” rapid response team is not the best way to intervene.
Chen J, Bellomo R, Flabouris A, Hillman K, Finfer S; MERIT Study Investigators for the Simpson Centre; ANZICS Clinical Trials Group. The relationship between early emergency team calls and serious adverse events. Crit Care Med. 2009 Jan;37(1):148-53.
UK NHS National Patient Safety Agency. Safer care for the acutely ill patient: learning from serious incidents. 2007
NICE (National Institute for Health and Clinical Excellence). Acutely ill patients in hospital. Recognition of and response to acute illness in adults in hospital. July 2007
Update: See also our December 29, 2009 Patient Safety Tip of the Week “Recognizing Deteriorating Patients”.