What is a MET (Medical Emergency Team) call?

From the Guidelines

A MET (Medical Emergency Team) call is a rapid response system activated when a patient shows signs of clinical deterioration in a hospital setting, triggered by specific criteria such as abnormal vital signs or altered mental status, with the purpose of providing early intervention to prevent cardiac arrests, unplanned ICU admissions, and deaths. This system involves summoning a specialized team of healthcare professionals, typically including critical care nurses, respiratory therapists, and physicians, who respond quickly to assess and treat patients before their condition becomes life-threatening 1. The deployment of a designated RRT/MET with expertise in addressing clinical deterioration has been shown to lead to a reduction in mortality and cardiac arrest, with moderate certainty evidence from four randomized controlled trials 1.

The criteria for activating a MET call may include abnormal vital signs, such as low blood pressure, rapid heart rate, or decreased oxygen saturation, as well as altered mental status or serious concerns about a patient's condition 1. The team responds quickly to assess and treat patients, bringing critical care expertise directly to the patient's bedside, allowing for prompt assessment, stabilization, and determination of appropriate next steps in care.

Key aspects of MET calls include:

• Early intervention for deteriorating patients
• Prevention of cardiac arrests, unplanned ICU admissions, and deaths
• Bringing critical care expertise directly to the patient's bedside
• Prompt assessment, stabilization, and determination of appropriate next steps in care
• Improvement of patient outcomes by addressing medical emergencies before they progress to more serious conditions 1.

It is essential to note that the composition of the responding teams, the consistency of team activation and response, as well as the elements comprising the early warning scoring systems, may vary widely between hospitals, making widespread scientific conclusions on the efficacy of such interventions difficult 1. However, the most recent evidence suggests that MET systems are an important safety mechanism in modern hospital care, and their implementation can lead to improved patient outcomes 1.

From the Research

Definition of a MET Call

• A MET (Medical Emergency Team) call is a request for emergency assistance from a team of doctors and nurses with advanced life support skills, in response to a deterioration in a patient's clinical condition 2.
• The MET team is hospital-based and provides a proactive response to a wide range of emergencies, aiming to prevent irreversible organ failure and cardiopulmonary arrest 3.

Reasons for MET Calls

• The most common reasons for MET calls include:
  • Staff concern 4
  • Low peripheral oxygen saturation (SpO2) not responding to oxygen therapy 4
  • Chest pain 3
  • Cardiopulmonary arrest 3
  • Seizures 3
  • Respiratory distress 3
• Abnormal respiratory rate is also a trigger for MET calls, although it is less frequent 4.

Outcomes of MET Calls

• The introduction of MET systems has been linked to a reported reduction in adverse outcomes and early recognition and intervention in clinically deteriorating patients 2.
• In-hospital mortality after a MET call can be significant, with one study reporting a mortality rate of 22% 4.
• A high proportion of patients who receive MET calls may require admission to Intensive Care Unit (ICU) 5.

Implementation and Effectiveness of MET Systems

• The effectiveness of MET systems depends on various factors, including education, resources, and communication 2.
• The implementation of MET systems can facilitate an integrated and coordinated approach to patient care, increase awareness of at-risk patients, and encourage early referral of seriously ill patients to clinicians with expertise in critical care 6.
• The MET system also empowers nursing staff and junior medical staff to call for immediate assistance in cases where they are seriously concerned about a patient 6.