INTRODUCTION
Rapid response systems identify deteriorating hospitalized patients prospectively and seek to alter their clinical trajectory through increasing the clinical resources directed to them [1]. As hospitalized patients may exhibit warning signs prior to deterioration [2,3], rapid response systems have the potential to prevent adverse clinical outcomes, including cardiac arrest and death.Rapid response systems are being utilized increasingly throughout the world, particularly in developed countries [4,5]. In 2005, the Institute for Healthcare Improvement made implementation of rapid response systems a key part of the 100,000 Lives Campaign to improve the quality of care in hospitals and reduce mortality rates [6]. However, the evidence supporting rapid response systems is limited, and it remains controversial whether these systems of care are effective [7-9].
In this topic, we discuss the rationale for rapid response systems and current evidence for their use in adults. Rapid response systems in the pediatric population and specific treatments in the management of critically ill patients are reviewed separately. (See "Overview of sudden cardiac arrest and sudden cardiac death" and "Advanced cardiac life support (ACLS) in adults" and "Pediatric advanced life support (PALS)", section on 'Rapid response teams'.)
DEFINITIONS
Rapid response systems are programs that are designed to improve the safety of hospitalized patients whose condition is deteriorating quickly [10]. They are based on prospective identification of high-risk patients, early notification of a team of responders who have been preselected and trained, rapid intervention by the response team, and ongoing evaluation of the system’s performance.Several terms are used to refer to rapid response systems. These terms include critical care outreach, medical emergency teams, medical response teams, and rapid response teams. There are subtle differences between these terms, but all maintain two key features: an afferent limb (ie, how the team is activated) and an efferent limb (ie, the response of the team). Medical emergency teams typically refer to physician-led teams that have the ability to manage complex airway issues, establish central access, and initiate intensive care unit (ICU) level care at the bedside [10]. Rapid response teams are generally nurse-led teams [10]. Critical care outreach is slightly different from the other terms in that critical care outreach also focuses on educating non-critical care staff and improving transfers between ICUs and the general hospital wards.