Michael Buist

Effects of a medical emergency team on reduction of incidence of and mortality from unexpected cardiac arrests in hospital: preliminary study

Abstract Objectives: To determine whether earlier clinical intervention by a medical emergency team prompted by clinical instability in a patient could reduce the incidence of and mortality from unexpected cardiac arrest in hospital. Design: A non-randomised, population based study before (1996) and after (1999) introduction of the medical emergency team. Setting: 300 bed tertiary referral teaching hospital. Participants: All patients admitted to the hospital in 1996 (n=19 317) and 1999 (n=22 847). Interventions: Medical emergency team (two doctors and one senior intensive care nurse) attended clinically unstable patients immediately with resuscitation drugs, fluid, and equipment. Response activated by the bedside nurse or doctor according to predefined criteria. Main outcome measures: Incidence and outcome of unexpected cardiac arrest. Results: The incidence of unexpected cardiac arrest was 3.77 per 1000 hospital admissions (73 cases) in 1996 (before intervention) and 2.05 per 1000 admissions (47 cases) in 1999 (after intervention), with mortality being 77% (56 patients) and 55% (26 patients), respectively. After adjustment for case mix the intervention was associated with a 50% reduction in the incidence of unexpected cardiac arrest (odds ratio 0.50, 95% confidence interval 0.35 to 0.73). Conclusions: In clinically unstable inpatients early intervention by a medical emergency team significantly reduces the incidence of and mortality from unexpected cardiac arrest in hospital. What is already known on this topic In most studies mortality from unexpected cardiac arrest in hospital exceeds 50% Such events are usually preceded by signs of clinical deterioration in the hours before cardiac arrest What this paper adds Early intervention by a medical emergency team significantly reduced the incidence of and mortality from unexpected cardiac arrest in hospital

Findings of the First Consensus Conference on Medical Emergency Teams

Background:Studies have established that physiologic instability and services mismatching precede adverse events in hospitalized patients. In response to these considerations, the concept of a Rapid Response System (RRS) has emerged. The responding team is commonly known as a medical emergency team (MET), rapid response team (RRT), or critical care outreach (CCO). Studies show that an RRS may improve outcome, but questions remain regarding the benefit, design elements, and advisability of implementing a MET system. Methods:In June 2005 an International Conference on Medical Emergency Teams (ICMET) included experts in patient safety, hospital medicine, critical care medicine, and METs. Seven of 25 had no experience with an RRS, and the remainder had experience with one of the three major forms of RRS. After preconference telephone and e-mail conversations by the panelists in which questions to be discussed were characterized, literature reviewed, and preliminary answers created, the panelists convened for 2 days to create a consensus document. Four major content areas were addressed: What is a MET response? Is there a MET syndrome? What are barriers to METS? How should outcome be measured? Panelists considered whether all hospitals should implement an RRS. Results:Patients needing an RRS intervention are suddenly critically ill and have a mismatch of resources to needs. Hospitals should implement an RRS, which consists of four elements: an afferent, “crisis detection” and “response triggering” mechanism; an efferent, predetermined rapid response team; a governance/administrative structure to supply and organize resources; and a mechanism to evaluate crisis antecedents and promote hospital process improvement to prevent future events.

Induced hypothermia using large volume, ice-cold intravenous fluid in comatose survivors of out-of-hospital cardiac arrest:: a preliminary report

STUDY HYPOTHESIS Recent studies have shown that induced hypothermia for twelve to twenty four hours improves outcome in patients who are resuscitated from out-of-hospital cardiac arrest. These studies used surface cooling, but this technique provided for relatively slow decreases in core temperature. Results from animal models suggest that further improvements in outcome may be possible if hypothermia is induced earlier after resuscitation from cardiac arrest. We hypothesized that a rapid infusion of large volume (30 ml/kg), ice-cold (4 degrees C) intravenous fluid would be a safe, rapid and inexpensive technique to induce mild hypothermia in comatose survivors of out-of-hospital cardiac arrest. METHODS We enrolled 22 patients who were comatose following resuscitation from out-of-hospital cardiac arrest. After initial evaluation in the Emergency Department (ED), a large volume (30 ml/kg) of ice-cold (4 degrees C) lactated Ringers solution was infused intravenously over 30 min. Data on vital signs, arterial blood gas, electrolyte and hematological was collected immediately before and after the infusion. RESULTS The rapid infusion of large volume, ice-cold crystalloid fluid resulted in a significant decrease in median core temperature from 35.5 to 33.8 degrees C. There were also significant improvements in mean arterial blood pressure, renal function and acid-base analysis. No patient developed pulmonary odema. CONCLUSION A rapid infusion of large volume, ice-cold crystalloid fluid is an inexpensive and effective method of inducing mild hypothermia in comatose survivors of out-of-hospital cardiac arrest, and is associated with beneficial haemodynamic, renal and acid-base effects. Further studies of this technique are warranted.

Induced hypothermia in critical care medicine: a review.

BackgroundClinical trials of induced hypothermia have suggested that this treatment may be beneficial in selected patients with neurologic injury. ObjectivesTo review the topic of induced hypothermia as a treatment of patients with neurologic and other disorders. DesignReview article. InterventionsNone. Main ResultsImproved outcome was demonstrated in two prospective, randomized, controlled trials in which induced hypothermia (33°C for 12–24 hrs) was used in patients with anoxic brain injury following resuscitation from prehospital cardiac arrest. In addition, prospective, randomized, controlled trials have been conducted in patients with severe head injury, with variable results. There also have been preliminary clinical studies of induced hypothermia in patients with severe stroke, newborn hypoxic-ischemic encephalopathy, neurologic infection, and hepatic encephalopathy, with promising results. Finally, animal models have suggested that hypothermia that is induced rapidly following traumatic cardiac arrest provides significant neurologic protection and improved survival. ConclusionsInduced hypothermia has a role in selected patients in the intensive care unit. Critical care physicians should be familiar with the physiologic effects, current indications, techniques, and complications of induced hyperthermia.

Six year audit of cardiac arrests and medical emergency team calls in an Australian outer metropolitan teaching hospital

Problem In-hospital cardiac arrest often represents failure of optimal clinical care. The use of medical emergency teams to prevent such events is controversial. In-hospital cardiac arrests have been reduced in several single centre historical control studies, but the only randomised prospective study showed no such benefit. In our hospital an important problem was failure to call the medical emergency team or cardiac arrest team when, before in-hospital cardiac arrest, patients had fulfilled the criteria for calling the team. Design Single centre, prospective audit of cardiac arrests and data on use of the medical emergency team during 2000 to 2005. Setting 400 bed general outer suburban metropolitan teaching hospital. Strategies for change Three initiatives in the hospital to improve use of the medical emergency team: orientation programme for first year doctors, professional development course for medical registrars, and the evolving role of liaison intensive care unit nurses. Key measures for improvement Incidence of cardiac arrests. Effects of the change Incidence of cardiac arrests decreased 24% per year, from 2.4/1000 admissions in 2000 to 0.66/1000 admissions in 2005. Lessons learnt Medical emergency teams can be efficacious when supported with a multidisciplinary, multifaceted education system for clinical staff.

What stops hospital clinical staff from following protocols? An analysis of the incidence and factors behind the failure of bedside clinical staff to activate the rapid response system in a multi-campus Australian metropolitan healthcare service

Objective To explore the causes of failure to activate the rapid response system (RRS). The organisation has a recognised incidence of staff failing to act when confronted with a deteriorating patient and leading to adverse outcomes. Design A multi-method study using the following: a point prevalence survey to determine the incidence of abnormal simple bedside observations and activation of the rapid response team by clinical staff; a prospective audit of all patients experiencing a cardiac arrest, unplanned intensive care unit admission or death over an 8-week period; structured interviews of staff to explore cognitive and sociocultural barriers to activating the RRS. Setting Southern Health is a comprehensive healthcare network with 570 adult in-patient beds across four metropolitan teaching hospitals in the south-eastern sector of Melbourne. Measurements Frequency of physiological instability and outcomes within the in-patient hospital population. Qualitative data from staff interviews were thematically coded. Results The incidence of physiological instability in the acute adult population was 4.04%. Nearly half of these patients (42%) did not receive an appropriate clinical response from the staff, despite most (69.2%) recognising their patient met physiological criteria for activating the RRS, and being ‘quite’, or ‘very’ concerned about their patient (75.8%). Structured interviews with 91 staff members identified predominantly sociocultural reasons for failure to activate the RRS. Conclusions Despite an organisational commitment to the RRS, clinical staff act on local cultural rules within the clinical environment that are usually not explicit. Better understanding of these informal rules may lead to more appropriate activation of the RRS.

Experience with prolonged induced hypothermia in severe head injury

BackgroundRecent prospective controlled trials of induced moderate hypothermia (32–34°C) for relatively short periods (24–48 h) in patients with severe head injury have suggested improvement in intracranial pressure control and outcome. It is possible that increased benefit might be achieved if hypothermia was maintained for more periods longer than 48 h, but there is little in the literature on the effects of prolonged moderate hypothermia in adults with severe head injury. We used moderate induced hypothermia (30–33°C) in 43 patients with severe head injury for prolonged periods (mean 8 days, range 2–19 days).ResultsAlthough nosocomial pneumonia (defined in this study as both new chest radiograph changes and culture of a respiratory pathogen from tracheal aspirate) was quite common (45%), death from sepsis was rare (5%). Other findings included hypokalaemia on induction of hypothermia and a decreasing total white cell and platelet count over 10 days. There were no major cardiac arrhythmias. There was a satisfactory neurological outcome in 20 out of 43 patients (47%).ConclusionModerate hypothermia may be induced for more prolonged periods, and is a relatively safe and feasible therapeutic option in the treatment of selected patients with severe traumatic brain injury. Thus, further prospective controlled trials using induced hypothermia for longer periods than 48 h are warranted.

The rapid response team paradox : Why doesn't anyone call for help?

The medical emergency team (MET) or rapid response team (RRT) system is a system of care for clinically unstable patients in the general ward areas of hospitals. When observations at a patients bedside breach predetermined levels of abnormality or the bedside nursing staff is worried about a pa

Why don't hospital staff activate the rapid response system (RRS)? How frequently is it needed and can the process be improved?

BackgroundThe rapid response system (RRS) is a process of accessing help for health professionals when a patient under their care becomes severely ill. Recent studies and meta-analyses show a reduction in cardiac arrests by a one-third in hospitals that have introduced a rapid response team, although the effect on overall hospital mortality is less clear. It has been suggested that the difficulty in establishing the benefit of the RRS has been due to implementation difficulties and a reluctance of clinical staff to call for additional help. This assertion is supported by the observation that patients continue to have poor outcomes in our institution despite an established RRS being available. In many of these cases, the patient is often unstable for many hours or days without help being sought. These poor outcomes are often discovered in an ad hoc fashion, and the real numbers of patients who may benefit from the RRS is currently unknown. This study has been designed to answer three key questions to improve the RRS: estimate the scope of the problem in terms of numbers of patients requiring activation of the RRS; determine cognitive and socio-cultural barriers to calling the Rapid Response Team; and design and implement solutions to address the effectiveness of the RRS.MethodsThe extent of the problem will be addressed by establishing the incidence of patients who meet abnormal physiological criteria, as determined from a point prevalence investigation conducted across four hospitals. Follow-up review will determine if these patients subsequently require intensive care unit or critical care intervention. This study will be grounded in both cognitive and socio-cultural theoretical frameworks. The cognitive model of situation awareness will be used to determine psychological barriers to RRS activation, and socio-cultural models of interprofessional practice will be triangulated to inform further investigation. A multi-modal approach will be taken using reviews of clinical notes, structured interviews, and focus groups. Interventions will be designed using a human factors analysis approach. Ongoing surveillance of adverse outcomes and surveys of the safety climate in the clinical areas piloting the interventions will occur before and after implementation.

Rapid response systems and collective (in)competence: An exploratory analysis of intraprofessional and interprofessional activation factors

Abstract The rapid response system (RRS) is a patient safety initiative instituted to enable healthcare professionals to promptly access help when a patient’s status deteriorates. Despite patients meeting the criteria, up to one-third of the RRS cases that should be activated are not called, constituting a “missed RRS call”. Using a case study approach, 10 focus groups of senior and junior nurses and physicians across four hospitals in Australia were conducted to gain greater insight into the social, professional and cultural factors that mediate the usage of the RRS. Participants’ experiences with the RRS were explored from an interprofessional and collective competence perspective. Health professionals’ reasons for not activating the RRS included: distinct intraprofessional clinical decision-making pathways; a highly hierarchical pathway in nursing, and a more autonomous pathway in medicine; and interprofessional communication barriers between nursing and medicine when deciding to make and actually making a RRS call. Participants also characterized the RRS as a work-around tool that is utilized when health professionals encounter problematic interprofessional communication. The results can be conceptualized as a form of collective incompetence that have important implications for the design and implementation of interprofessional patient safety initiatives, such as the RRS.