Background

Rapid response teams represent an intuitively simple concept: When a patient demonstrates signs of imminent clinical deterioration, a team of providers is summoned to the bedside to immediately assess and treat the patient with the goal of preventing intensive care unit transfer, cardiac arrest, or death. Such teams have become a widely used patient safety intervention due in large part to their inclusion in the Institute for Healthcare Improvement's "100,000 Lives Campaign" in 2005. However, the rapid response team concept has come to exemplify the tension between those arguing for swift implementation of conceptually attractive patient safety interventions supported by anecdotal evidence of benefit and those advocating a more rigorous, evidence-based—and inevitably slower—approach.

Patients whose condition deteriorates acutely while hospitalized often exhibit warning signs (such as abnormal vital signs) in the hours before experiencing adverse clinical outcomes. In contrast to standard cardiac arrest or "code blue" teams, which are summoned only after cardiopulmonary arrest occurs, rapid response teams are designed to intervene during this critical period, usually on patients on general medical or surgical wards.

Several different models of rapid response teams exist (see Table 1), and a 2006 consensus conference advocated use of the term "rapid response system" (RRS) as a unifying term. Hospitalists are increasingly assuming RRS duties, either as the primary responder or to assist nurse-led teams.

A useful construct is to consider RRSs as having "afferent" (the criteria for calling) and "efferent" (responsive) arms. Despite differences in team structure, the criteria used to summon the teams are generally similar. Bedside staff are encouraged to call the team when any of a number of prespecified criteria (Table 2) are met. At certain hospitals, patients and family members are also permitted to call the team. Recent research has focused on development of more sophisticated "track-and-trigger" bedside monitoring systems that could be used to automatically trigger intervention when certain physiologic abnormalities are detected.

Evidence of Effectiveness

Early publications on RRSs reported significant improvements in clinical outcomes, but multiple subsequent systematic reviews have found no consistent evidence that RRSs benefit patients. Also, little comparative data exists to support one RRS model over another, nor are there data on the cost-effectiveness of RRS. The reasons for RRSs' apparent lack of effect are complex, and in some cases, may relate to local practice and cultural reasons that result in the team being underutilized.

The RRS concept thus became an example of "the tension between needing to improve care and knowing how to do it." Proponents argued that the face validity and potential benefit of RRS justify immediate implementation, while others advocated for further research to define optimal team structure and patient populations most likely to benefit before mandating RRS implementation. Interestingly, the teams have proven to be a very popular intervention among nursing staff, and qualitative analyses of RRS functioning have helped identify systematic problems in care and deficiencies in safety culture at several institutions. These factors alone may justify implementation of some form of RRS.

Current Context

The strong endorsement of RRSs by the Institute for Healthcare Improvement, coupled with the 2008 Joint Commission National Patient Safety Goal—which does not mandate RRS per se but does require hospitals to implement systems to enable "healthcare staff members to directly request additional assistance from a specially trained individual(s) when the patient's condition appears to be worsening"—have led to widespread implementation of RRS, despite continued controversy around their clinical benefit. It is likely that some form of RRS exists in most US hospitals, as nearly half of had established a rapid response team as of 2006.