Effectiveness of the Medical Emergency Team: the importance of dose

Abstract

Up to 17% of hospital admissions are complicated by serious adverse events unrelated to the patients presenting medical condition. Rapid Response Teams (RRTs) review patients during early phase of deterioration to reduce patient morbidity and mortality. However, reports of the efficacy of these teams are varied. The aims of this article were to explore the concept of RRT dose, to assess whether RRT dose improves patient outcomes, and to assess whether there is evidence that inclusion of a physician in the team impacts on the effectiveness of the team. A review of available literature suggested that the method of reporting RRT utilization rate, (RRT dose) is calls per 1,000 admissions. Hospitals with mature RRTs that report improved patient outcome following RRT introduction have a RRT dose between 25.8 and 56.4 calls per 1,000 admissions. Four studies report an association between increasing RRT dose and reduced in-hospital cardiac arrest rates. Another reported that increasing RRT dose reduced in-hospital mortality for surgical but not medical patients. The MERIT study investigators reported a negative relationship between MET-like activity and the incidence of serious adverse events. Fourteen studies reported improved patient outcome in association with the introduction of a RRT, and 13/14 involved a Physician-led MET. These findings suggest that if the RRT is the major method for reviewing serious adverse events, the dose of RRT activation must be sufficient for the frequency and severity of the problem it is intended to treat. If the RRT dose is too low then it is unlikely to improve patient outcomes. Increasing RRT dose appears to be associated with reduction in cardiac arrests. The majority of studies reporting improved patient outcome in association with the introduction of an RRT involve a MET, suggesting that inclusion of a physician in the team is an important determinant of its effectiveness.

Rapid response teams improve outcomes: yes

“…There are typically fewer than 10 cardiac arrests per 1000 patient admissions [3][4][5]; however, mature RRTs review at least 20 patients per 1000 admissions [6] and a dose-response relationship between increasing RRT review rates and reducing cardiac arrests has been demonstrated [7]. RRTs also play a leading part in developing a safety-focused culture and patient-safety systems across hospitals, although it takes time for systems to mature, for barriers to be overcome, and for escalation of at-risk patients and learning from adverse events to become routine practice.…”

Pediatric Rapid Response Systems: Identification and Treatment of Deteriorating Children

“…Still, the level 1 evidence adds weight to the accumulating level 2-5 evidence and is sufficient to support implementation [10, 68, 78•, 79]. Beyond having a RRT, there is evidence in adults for a "dose-response" of RRT with 1 cardiac arrest potentially prevented for every 17 RRT calls [80]. That is, the more RRT calls, the greater reductions in CPA and mortality.…”

Designing a Critical Care Nurse–Led Rapid Response Team Using Only Available Resources: 6 Years Later

“…RRT success also appears to be linked to practice; if the RRT is widely adopted by clinicians, it appears more effective. 35,36 A higher call intensity, or "dose rate," more than 25 RRT calls per 1000 admissions, is reported to be associated with decreases in cardiac arrest rate, 37 and conversely when the RRT rate decreases, the cardiac arrest rate increases. 36 The RRT must be used to be effective, and if it is not used, benefits may not be manifested.…”