Cost effectiveness and cost utility model of public place defibrillators in improving survival after prehospital cardiopulmonary arrest

Economic evaluation of automated external defibrillator deployment in public settings for out-of-hospital cardiac arrest: a systematic review

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) is a major issue in aging populations. The use of automatic external defibrillators (AEDs) in public places improves cardiac arrest survival rates. The purpose of this study is to review economic evaluation studies of the use of AED technology in public settings for cardiac arrest resuscitation.

METHODS

Our search covered 1990-2021 and included PubMed, Cochrane Library, Embase, Scopus, and Web of Science. We included studies that analyzed cost-effectiveness, cost-utility and cost-benefit of the AED technology. Also, we performed the quality assessment of the studies through the checklist of quality assessment standard of health economic studies (QHES).

RESULTS

Our inclusion criteria were met by 25 studies. AEDs are found to be cost-effective in places with a high occurrence of cardiac arrest. In addition, proper integration of drones with AEDs into existing systems has the potential to significantly improve OHCA survival rates.

CONCLUSION

The present study found that putting AEDs in high-cardiac arrest and crowded areas reduces average costs. Despite this, the costs associated with acquiring and maintaining AEDs prevent their widespread use. Further research is needed to evaluate feasibility and explore innovative strategies for AED maintenance and accessibility.

Out-of-Hospital Cardiac Arrest in a Teaching Hospital in Hong Kong: Descriptive Study Using the Utstein Style

Objective

To describe, using the Utstein template, the characteristics of patients presenting with out-of-hospital cardiac arrest to a university teaching hospital in the New Territories of Hong Kong, and to evaluate survival.

Design

Prospective study.

Setting

The emergency department of a teaching hospital in the New Territories, Hong Kong.

Participants

Patients older than 12 years with non-traumatic out-of-hospital cardiac arrest who were transported to the hospital between 1 July 2002 and 31 December 2002.

Main outcome measures

Demographic data, characteristics of cardiac arrest and response time intervals of the emergency medical service presented according to the Utstein style, and also survival to hospital discharge rate.

Results

A total of 124 patients were included (49.2% male; mean age 71.9 years). The majority of cardiac arrests occurred in patients' home. The overall bystander cardiopulmonary resuscitation (CPR) rate was 15.3% (19/124). The most common electrocardiographic rhythm at scene was asystole, whilst pulseless ventricular tachycardia (VT)/ventricular fibrillation (VF) was found in 18.0%. The overall survival was 0.8% (1/124), and survival to hospital discharge was significantly higher for patients with VF or pulseless VT than those patients with other rhythms of cardiac arrest (11.1% versus 0%). The median witnessed/recognised collapse to defibrillation time was 14 minutes. The median prehospital time interval from collapse/recognition to arrival at hospital was 33 minutes.

Conclusion

The prognosis of out-of-hospital cardiac arrest in Hong Kong was poor. Major improvements in every component of the chain of survival are necessary.

Bystander automated external defibrillator use and clinical outcomes after out-of-hospital cardiac arrest: A systematic review and meta-analysis

AIM

To systematically review studies comparing bystander automated external defibrillator (AED) use to no AED use in regard to clinical outcomes in out-of-hospital cardiac arrest (OHCA), and to provide a descriptive summary of studies on the cost-effectiveness of bystander AED use.

METHODS

We searched Medline, Embase, the Web of Science, and the Cochrane Library for randomized trials and observational studies published before June 1, 2017. Meta-analyses were performed for patients with all rhythms, shockable rhythms, and non-shockable rhythms.

RESULTS

Forty-four observational studies, 3 randomized trials, and 13 cost-effectiveness studies were included. Meta-analysis of 6 observational studies without critical risk of bias showed that bystander AED use was associated with survival to hospital discharge (all rhythms OR: 1.73 [95%CI: 1.36, 2.18], shockable rhythms OR: 1.66 [95%CI: 1.54, 1.79]) and favorable neurological outcome (all rhythms OR: 2.12 [95%CI: 1.36, 3.29], shockable rhythms OR: 2.37 [95%CI: 1.58, 3.57]). There was no association between bystander AED use and neurological outcome for non-shockable rhythms (OR: 0.76 [95%CI: 0.10, 5.87]). The Public-Access Defibrillation trial found higher survival rates when volunteers were equipped with AEDs. The other trials found no survival difference, although their study settings differed. The quality of evidence was low for randomized trials and very low for observational studies. AEDs were cost-effective in settings with high cardiac arrest incidence, with most studies reporting ratios < $100,000 per quality-adjusted life years.

CONCLUSIONS

The evidence supports the association between bystander AED use and improved clinical outcomes, although the quality of evidence was low to very low.

Hospital costs of out-of-hospital cardiac arrest patients treated in intensive care; a single centre evaluation using the national tariff-based system

OBJECTIVES

There is a scarcity of literature reporting hospital costs for treating out of hospital cardiac arrest (OOHCA) survivors, especially within the UK. This is essential for assessment of cost-effectiveness of interventions necessary to allow just allocation of resources within the National Health Service. We set out primarily to calculate costs stratified against hospital survival and neurological outcomes. Secondarily, we estimated cost effectiveness based on estimates of survival and utility from previous studies to calculate costs per quality adjusted life year (QALY).

SETTING

We performed a single centre (London) retrospective review of in-hospital costs of patients admitted to the intensive care unit (ICU) following return of spontaneous circulation (ROSC) after OOHCA over 18 months from January 2011 (following widespread introduction of targeted temperature management and primary percutaneous intervention).

PARTICIPANTS

Of 69 successive patients admitted over an 18-month period, survival and cerebral performance category (CPC) outcomes were obtained from review of databases and clinical notes. The Trust finance department supplied ICU and hospital costs using the Payment by Results UK system.

RESULTS

Of those patients with ROSC admitted to ICU, survival to hospital discharge (any CPC) was 33/69 (48%) with 26/33 survivors in CPC 1-2 at hospital discharge. Cost per survivor to hospital discharge (including total cost of survivors and non-survivors) was £50,000, cost per CPC 1-2 survivor was £65,000. Cost and length of stay of CPC 1-2 patients was considerably lower than CPC 3-4 patients. The majority of the costs (69%) related to intensive care. Estimated cost per CPC 1-2 survivor per QALY was £16,000.

CONCLUSIONS

The costs of in-hospital patient care for ICU admissions following ROSC after OOHCA are considerable but within a reasonable threshold when assessed from a QALY perspective.

Cost-effectiveness of a national public access defibrillation programme

AIM

Proposed Irish legislation aimed at increasing survival from out-of-hospital-cardiac-arrest (OHCA) mandates the provision of automated external defibrillators (AEDs) in a comprehensive range of publicly accessible premises in urban and rural areas. This study estimated the clinical and cost effectiveness of the legislation, compared with alternative programme configurations involving more targeted AED placement.

METHODS

We used a cost-utility analysis to estimate the costs and consequences of public access defibrillation (PAD) programmes from a societal perspective, based on AED deployment by building type. Comparator programmes ranged from those that only included building types with the highest incidence of OHCA, to the comprehensive programme outline in the proposed legislation. Data on OHCA incidence and outcomes were obtained from the Irish Out-of-Hospital-Cardiac-Arrest Register (OHCAR). Costs were obtained from the Irish health service, device suppliers and training providers.

RESULTS

The incremental cost effectiveness ratio (ICER) for the most comprehensive PAD scheme was €928,450/QALY. The ICER for the most scaled-back programme involving AED placement in transport stations, medical practices, entertainment venues, schools (excluding primary) and fitness facilities was €95,640/QALY. A 40% increase in AED utilisation when OHCAs occur in a public area could potentially render this programme cost effective.

CONCLUSION

National PAD programmes involving widespread deployment of static AEDs are unlikely to be cost-effective. To improve cost-effectiveness any prospective programmes should target locations with the highest incidence of OHCA and be supported by efforts to increase AED utilisation, such as improving public awareness, increasing CPR and AED training, and establishing an EMS-linked AED register.

Favourable cost-benefit in an early defibrillation programme using dual dispatch of ambulance and fire services in out-of-hospital cardiac arrest

AIMS

Out-of-hospital cardiac arrest is fatal without treatment, and time to defibrillation is an extremely important factor in relation to survival. We performed a cost-benefit analysis of dual dispatch defibrillation by ambulance and fire services in the County of Stockholm, Sweden.

METHODS AND RESULTS

A cost-benefit analysis was performed to evaluate the effects of dual dispatch defibrillation. The increased survival rates were estimated from a real-world implemented intervention, and the monetary value of a life (<euro> 2.2 million) was applied to this benefit by using results from a recent stated-preference study. The estimated costs include defibrillators (including expendables/maintenance), training, hospitalisation/health care, fire service call-outs, overhead resources and the dispatch centre. The estimated number of additional saved lives was 16 per year, yielding a benefit-cost ratio of 36. The cost per quality-adjusted life years (QALY) was estimated to be <euro> 13,000, and the cost per saved life was <euro> 60,000.

CONCLUSIONS

The intervention of dual dispatch defibrillation by ambulance and fire services in the County of Stockholm had positive economic effects. For the cost-benefit analysis, the return on investment was high and the cost-effectiveness showed levels below the threshold value for economic efficiency used in Sweden. The cost-utility analysis categorises the cost per QALY as medium.

Spoilt for choice: implications of using alternative methods of costing hospital episode statistics

In the absence of a 'gold standard' to estimate the economic burden of disease, a decision about the most appropriate costing method is required. Researchers have employed various methods to cost hospital stays, including per diem or diagnosis-related group (DRG)-based costs. Alternative methods differ in data collection and costing methodology. Using data from Scotland as an illustrative example, costing methods are compared, highlighting the wider implications for other countries with a publicly financed healthcare system. Five methods are compared using longitudinal data including baseline survey data (Midspan) linked to acute hospital admissions. Cost variables are derived using two forms of DRG-type costs, costs per diem, costs per episode-using a novel approach that distinguishes between variable and fixed costs and incorporates individual length of stay (LOS), and costs per episode using national average LOS. Cost estimates are generated using generalised linear model regression. Descriptive analysis shows substantial variation between costing methods. Differences found in regression analyses highlight the magnitude of variation in cost estimates for subgroups of the sample population. This paper emphasises that any inference made from econometric modelling of costs, where the marginal effect of explanatory variables is assessed, is substantially influenced by the costing method.

Cost-effectiveness of acupuncture care as an adjunct to exercise-based physical therapy for osteoarthritis of the knee

BACKGROUND

The delivery of acupuncture alongside mainstream interventions and the cost-effectiveness of "alternative" treatments remain areas of controversy.

OBJECTIVE

The aim of this study was to assess the cost-utility of adding acupuncture to a course of advice and exercise delivered by UK National Health Service (NHS) physical therapists to people with osteoarthritis of the knee.

DESIGN

A cost-utility analysis was performed alongside a randomized controlled trial.

METHODS

A total of 352 adults (aged 50 years or older) were randomly assigned to receive 1 of 3 interventions. The primary analysis focused on participants receiving advice and exercise (AE) or advice and exercise plus true acupuncture (AE+TA). A secondary analysis considered participants receiving advice and exercise plus nonpenetrating acupuncture (AE+NPA). The main outcome measures were quality-adjusted life years (QALYs), measured by the EQ-5D, and UK NHS costs.

RESULTS

were expressed as the incremental cost per QALY gained over 12 months. Sensitivity analyses included a broader cost perspective to incorporate private out-of-pocket costs. Results NHS costs were higher for AE+TA (£314 [British pounds sterling]) than for AE alone (£229), and the difference in mean QALYs favored AE+TA (mean difference=0.022). The base-case cost per QALY gained was £3,889; this value was associated with a 77% probability that AE+TA would be more cost-effective than AE at a threshold of £20,000 per QALY. Cost-utility data for AE+NPA provided cost-effectiveness estimates similar to those for AE+TA.

LIMITATIONS

As with all trial-based economic evaluations, caution should be exercised when generalizing results beyond the study perspectives.

CONCLUSIONS

A package of AE+TA delivered by NHS physical therapists provided a cost-effective use of health care resources despite an associated increase in costs. However, the economic benefits could not be attributed to the penetrating nature of conventional acupuncture; therefore, further research regarding the mechanisms of acupuncture is needed. An analysis of alternative cost perspectives suggested that the results are generalizable to other health care settings.

Public access defibrillation: time to access the public

STUDY OBJECTIVE

Public accessible automated external defibrillators (AEDs) are increasingly made available in highly frequented places, allowing coincidental bystanders to defibrillate with minimal delay if necessary. Although the public, as the largest and most readily available group of potential rescuers, is assigned a key role in this concept of "public" access defibrillation, it is unknown whether bystanders are actually sufficiently prepared. We therefore investigate knowledge and attitudes toward AEDs among the public.

METHODS

Standardized interviews were conducted at the Central Railway Station of Amsterdam, the Netherlands, a highly frequented and AED-equipped public place with a high number of travelers and visitors from all over the world.

RESULTS

Surveys from 1,018 participants from a total of 38 nations were analyzed, revealing a considerable lack of knowledge among the public. Less than half of participants (47%) would be willing to use an AED, and more than half (53%) were unable to recognize an AED. Overall, only a minority of individuals have sufficient knowledge and would be willing to use an AED. Differences between subgroups were identified, which may aid to tailor public information campaigns to specific target audiences.

CONCLUSION

Only a minority of individuals demonstrate sufficient knowledge and willingness to operate an AED, suggesting that the public is not yet sufficiently prepared for the role it is destined for. Wide-scale public information campaigns are an important next step to exploit the lifesaving potential of public access defibrillation.

Hospital costs and revenue are similar for resuscitated out-of-hospital cardiac arrest and ST-segment acute myocardial infarction patients

OBJECTIVES

Care provided to patients who survive to hospital admission after out-of-hospital cardiac arrest (OOHCA) is sometimes viewed as expensive and a poor use of hospital resources. The objective was to describe financial parameters of care for patients resuscitated from OOHCA.

METHODS

This was a retrospective review of OOHCA patients admitted to one academic teaching hospital from January 2004 to October 2007. Demographic data, length of stay (LOS), and discharge disposition were obtained for all patients. Financial parameters of patient care including total cost, net revenue, and operating margin were calculated by hospital cost accounting and reported as median and interquartile range (IQR). Groups were dichotomized by survival to discharge for subgroup analysis. To provide a reference group for context, similar financial data were obtained for ST-segment elevation myocardial infarction (STEMI) patients admitted during the same time period, reported with medians and IQRs.

RESULTS

During the study period, there were 72 admitted OOCHA patients and 404 STEMI patients. OOCHA and STEMI groups were similar for age, sex, and insurance type. Overall, 27 (38.6%) OOHCA patients survived to hospital discharge. Median LOS for OOHCA patients was 4 days (IQR = 1-8 days), with most of those hospitalized for <or=4 days (n = 34, 81.0% dying or discharged to hospice care). Median net revenue ($17,334 [IQR $7,015-$37,516] vs. $16,466 [IQR = $14,304-$23,678], p = 0.64) and operating margin ($7,019 [IQR = $1,875-$15,997] vs. $7,098 [IQR = $3,767-$11,138], p = 0.83) for all OOHCA patients were not different from STEMI patients. Net income for OOCHA patients was not different than for STEMI patients (-$322 vs. $114, p = 0.72).

CONCLUSIONS

Financial parameters for OOHCA patients are similar to those of STEMI patients. Financial issues should not be a negative incentive to providing care for these patients.

Support and Assessment for Fall Emergency Referrals (SAFER 1) trial protocol. Computerised on-scene decision support for emergency ambulance staff to assess and plan care for older people who have fallen: evaluation of costs and benefits using a pragmatic cluster randomised trial

Background

Many emergency ambulance calls are for older people who have fallen. As half of them are left at home, a community-based response may often be more appropriate than hospital attendance. The SAFER 1 trial will assess the costs and benefits of a new healthcare technology - hand-held computers with computerised clinical decision support (CCDS) software - to help paramedics decide who needs hospital attendance, and who can be safely left at home with referral to community falls services.

Methods/Design

Pragmatic cluster randomised trial with a qualitative component. We shall allocate 72 paramedics ('clusters') at random between receiving the intervention and a control group delivering care as usual, of whom we expect 60 to complete the trial.

Patients are eligible if they are aged 65 or older, live in the study area but not in residential care, and are attended by a study paramedic following an emergency call for a fall. Seven to 10 days after the index fall we shall offer patients the opportunity to opt out of further follow up. Continuing participants will receive questionnaires after one and 6 months, and we shall monitor their routine clinical data for 6 months. We shall interview 20 of these patients in depth. We shall conduct focus groups or semi-structured interviews with paramedics and other stakeholders.

The primary outcome is the interval to the first subsequent reported fall (or death). We shall analyse this and other measures of outcome, process and cost by 'intention to treat'. We shall analyse qualitative data thematically.

Discussion

Since the SAFER 1 trial received funding in August 2006, implementation has come to terms with ambulance service reorganisation and a new national electronic patient record in England. In response to these hurdles the research team has adapted the research design, including aspects of the intervention, to meet the needs of the ambulance services.

In conclusion this complex emergency care trial will provide rigorous evidence on the clinical and cost effectiveness of CCDS for paramedics in the care of older people who have fallen.

Trial Registration

ISRCTN10538608

Location of cardiac arrest in a city center: strategic placement of automated external defibrillators in public locations

BACKGROUND

Public-access defibrillation with automated external defibrillators (AEDs) is being implemented in many countries worldwide with considerable financial implications. The potential benefit and economic consequences of focused or unfocused AED deployment are unknown.

METHODS AND RESULTS

All cardiac arrests in public in Copenhagen, Denmark, from 1994 through 2005 were geographically located, as were 104 public AEDs placed by local initiatives. In accordance with European Resuscitation Council and American Heart Association (AHA) guidelines, areas with a high incidence of cardiac arrests were defined as those with 1 cardiac arrest every 2 or 5 years, respectively. There were 1274 cardiac arrests in public locations. According to the European Resuscitation Council or AHA guidelines, AEDs needed to be deployed in 1.2% and 10.6% of the city area, providing coverage for 19.5% (n=249) and 66.8% (n=851) of all cardiac arrests, respectively. The excessive cost of such AED deployments was estimated to be $33 100 or $41 000 per additional quality-adjusted life year, whereas unguided AED placement covering the entire city had an estimated cost of $108 700 per quality-adjusted life year. Areas with major train stations (1.8 arrests every 5 years per area), large public squares, and pedestrianized areas (0.6 arrests every 5 years per area) were main predictors of frequent cardiac arrests.

CONCLUSIONS

To achieve wide AED coverage, AEDs need to be more widely distributed than recommended by the European Resuscitation Council guidelines but consistent with the American Heart Association guidelines. Strategic placement of AEDs is pivotal for public-access defibrillation, whereas with unguided initiatives, AEDs are likely to be placed inappropriately.

Out of hospital cardiac arrest outside home in Sweden, change in characteristics, outcome and availability for public access defibrillation

Background

A large proportion of patients who suffer from out of hospital cardiac arrest (OHCA) outside home are theoretically candidates for public access defibrillation (PAD). We describe the change in characteristics and outcome among these candidates in a 14 years perspective in Sweden.

Methods

All patients who suffered an OHCA in whom cardiopulmonary resuscitation (CPR) was attempted between 1992 and 2005 and who were included in the Swedish Cardiac Arrest Register (SCAR). We included patients in the survey if OHCA took place outside home excluding crew witnessed cases and those taken place in a nursing home.

Results

26% of all OHCAs (10133 patients out of 38710 patients) fulfilled the inclusion criteria. Within this group, the number of patients each year varied between 530 and 896 and the median age decreased from 68 years in 1992 to 64 years in 2005 (p for trend = 0.003). The proportion of patients who received bystander CPR increased from 47% in 1992 to 58% in 2005 (p for trend < 0.0001). The proportion of patients found in ventricular fibrillation (VF) declined from 56% to 50% among witnessed cases (p for trend < 0.0001) and a significant (p < 0.0001) decline was also seen among non witnessed cases.

The median time from cardiac arrest to defibrillation among witnessed cases was 12 min in 1992 and 10 min in 2005 (p for trend = 0.029). Survival to one month among all patients increased from 8.1% to 14.0% (p for trend = 0.01). Among patients found in a shockable rhythm survival increased from 15.3% in 1992 to 27.0% in 2005 (p for trend < 0.0001).

Conclusion

In Sweden, there was a change in characteristics and outcome among patients who suffer OHCA outside home. Among these patients, bystander CPR increased, but the occurrence of VF decreased. One-month survival increased moderately overall and highly significantly among patients found in VF, even though the time to defibrillation changed only moderately.

Ventricular fibrillation and defibrillation

Cardiac arrest in children is not often due to a disturbance in rhythm that is amenable to electrical defibrillation, contrary to the situation in adults. When a shockable rhythm is present, defibrillation using an external electric shock applied at an early stage after pre-oxygenation and chest compressions is of proven efficacy. Success at conversion of ventricular fibrillation is dependent on the delay before delivering the shock and defibrillation efficiency, which is itself a function of thoracic impedance, energy dose and waveform.

[Public access defibrillation. Limited use by trained first responders and laymen]

As ventricular fibrillation is the most frequent initial heart rhythm causing out-of-hospital sudden cardiac arrest, defibrillation is of essential significance. Automated external defibrillators (AEDs) have been available for some years and as a result defibrillation can be carried out by individuals other than physicians and healthcare providers such as trained first responders and untrained lay rescuers. This so-called public access defibrillation nourished hope of progress in the treatment of sudden cardiac arrest. However, several limitations exist, such as low frequency of sudden cardiac arrest in public, rare use of publicly placed AEDs, low cost effectiveness, legal requirements and insufficient public willingness to help. Due to these restrictions of public access defibrillation other measures are more promising than the attempt at general distribution of AEDs. These measures are primary or secondary prophylaxis of sudden cardiac arrest, general knowledge of adequate activation of emergency medical services, implementation of first responder teams equipped with AEDs and particularly a better education in and application of the well-established principles of cardiopulmonary resuscitation.

Cost-effectiveness of automated external defibrillators in public places: con

PURPOSE OF REVIEW

To discuss the clinical effectiveness, public health impact and cost-effectiveness of public access defibrillation.

RECENT FINDINGS

High rates of survival from prehospital ventricular fibrillation have been documented in patients treated by first responders using automated external defibrillators. The recent Public Access Defibrillation trial demonstrated a doubling of cardiac arrest survival in community units where volunteers trained in cardiopulmonary resuscitation were additionally equipped with automated external defibrillators. The cost-effectiveness analysis of the Public Access Defibrillation trial has not yet been published, and previous analyses have lacked full data on cost, outcome, or both. Data from many sources indicate that automated external defibrillator placement at sites with an expected rate of one cardiac arrest per defibrillator per 5 years, as recommended by the American Heart Association, addresses only around 1-2% of prehospital arrests, and will have a minimal impact on population survival.

SUMMARY

While highly targeted provision of automated external defibrillators in areas of greatest risk, such as casinos and airports, may be cost-effective, it will have little impact at a population level. Provision of more widespread public access defibrillation to sites with lower incidence of cardiac arrest is unlikely to be cost-effective, and may represent poorer value for money than alternative healthcare interventions in coronary artery disease.

La desfibrilación temprana en la comunidad: romper barreras para salvar vidas

It is considered that in Spain, every year, we have more than 24,500 out-of-hospital cardiac arrests. Around 85% of these are secondary to ventricular fibrillation, with possibility of reversion in more than 90% if defibrillation is performed in the first minute of arrhythmia. However, if we delay this defibrillation, survival possibilities disappear in a few minutes. Clinical advances in last decades have not achieved satisfactory results in the treatment of cardiac arrest as survival rates at hospital discharge do not exceed 7%. Aware of this situation, the International Scientific Societies are recommending decreasing time to defibrillation, advising, at best, a time less than five minutes between the 112-call (emergency) and adequate electric discharge. Development of automated defibrillators in Emergency Medical Systems and their use by <<first responders>> of <<non-health care>> emergency services (police, fire fighters, etc) contribute to reach this objective. Because of this, Emergency Medical Systems are modifying their assistance strategies, to implement the early defibrillation as <<key to survival>>. Literature showed the effective value of automated defibrillators in the public areas but their efficiency level is less than that reached with the Emergency Services. Efficiency depends on multiple factors such as type of installation, accessibility level to emergency medical services or incidence rate of sudden cardiac arrest. Thus, their introduction should be preceded by a cost-effectiveness study. Effectiveness of automated defibrillators at home, where up to 80% of cardiac arrest are produced, has still not been evaluated. Nevertheless, in the USA, its marketing with this indication has been authorized.

Future shock: automatic external defibrillators

PURPOSE OF REVIEW

This review provides a practical overview of the performance capabilities of automatic external defibrillators (AEDs), and of advances in technology and dissemination programmes for these devices.

RECENT FINDINGS

Arrhythmia analysis by AEDs is extremely reliable in most settings (sensitivity 81-100%, specificity 99.9-97.6%). Accurate detection of arrhythmias has also been demonstrated in children, leading the US Food and Drug Administration to approve the use of several AEDs in children aged 8 years or younger. Factors that potentially may reduce the quality of arrhythmia detection are the presence of wide complex supraventricular tachycardia and location of an arrythmic event near to high-power lines. AED use by professional basic life support providers resulted in increased survival in the prehospital setting. However, provision of AEDs to nonmedical rescue services did not result in universal improvement in patient outcome. Public access defibrillation programmes have led to higher rates of survival from cardiac arrest. The role of AEDs in hospitals has yet to be elucidated, although in-hospital mortality from ventricular arrhythmias has been shown to decrease following AED deployment.

SUMMARY

Given the correct setting, AEDs can ensure that defibrillation is not limited by lack of medical knowledge or difficulties in decision making. However, event-related variables and operator-related factors, that are yet to be determined, can significantly affect the efficacy of automatic external defibrillation.

Is a target culture in health care always compatible with efficient use of resources? A cost-effectiveness analysis of an intervention to achieve thrombolysis targets

BACKGROUND

The UK government has attempted to improve the quality of health care in the National Health Service and minimize geographical variations in quality by imposing targets in certain areas of health care. The measures taken by local health economies to achieve these targets have not before been subjected to cost-effectiveness analysis. We have assessed the cost effectiveness of an intervention designed to achieve thrombolysis time targets.

METHODS

In the setting of a single district general hospital in England, we audited local pain-to-needle (PTN) and door-to-needle (DTN) times, before and after a pounds 208,000 (Euro 310,000, dollar 370,000) annual expenditure to improve performance against government targets. The intervention included the recruitment of additional nursing time in the Accident & Emergency Department and the use of a single bolus thrombolytic agent for all patients with ST elevation myocardial infarction. An economic evaluation was performed, based on the expected number of additional lives saved, extrapolated from a meta-analysis of previous thrombolysis trials.

RESULTS

The intervention reduced mean DTN time from 37.6 +/- 5.9 minutes (mean +/- SEM) to 27.6 +/- 3.6 minutes (p = 0.06). The cost per life saved was pounds 3,423 +/- 850 (Euro 5,100,000, dollar 6,100,000), the cost per life year gained was pounds 222,184 (Euro 330,000, dollar 390,000) and the cost per quality-adjusted life year (QALY) gained was pounds 246,871 (Euro 370,000, dollar 440,000).

CONCLUSION

Although moderately successful at improving performance against government targets, this intervention to promote rapid thrombolysis proved to be an inefficient use of health-care resources. Strict government targets in health care may not always lead to efficient targeting of resources.

Use of automated external defibrillators in cardiac arrest: an evidence-based analysis

OBJECTIVE

The objectives were to identify the components of a program to deliver early defibrillation that optimizes the effectiveness of automated external defibrillators (AEDs) in out-of-hospital and hospital settings, to determine whether AEDs are cost-effective, and if cost-effectiveness was determined, to advise on how they should be distributed in Ontario.

CLINICAL NEED

Survival in people who have had a cardiac arrest is low, especially in out-of-hospital settings. With each minute delay in defibrillation from the onset of cardiac arrest, the probability of survival decreases by 10%. (1) Early defibrillation (within 8 minutes of a cardiac arrest) has been shown to improve survival outcomes in these patients. However, in out-of-hospital settings and in certain areas within a hospital, trained personnel and their equipment may not be available within 8 minutes. This implies that "first responders" should take up the responsibility of delivering shock. The first responders in out-of-hospital settings are usually bystanders, firefighters, police, and community volunteers. In hospital settings, they are usually nurses. These first responders are not trained in reading electrocardiograms and identifying abnormal heart rhythms restorable by defibrillation.

THE TECHNOLOGY

An AED is a device that can analyze a heart rhythm and deliver a shock if needed. Thus, AEDs can be used by first responders to deliver early defibrillation in out-of-hospital and hospital settings. However, simply providing an AED would not likely improve survival outcomes. Rather, AEDs have a role in strengthening the "chain of survival," which includes prompt activation of the 911 telephone system, early cardiopulmonary resuscitation (CPR), rapid defibrillation, and timely advanced life support. In the chain of survival, the first step for a witness of a cardiac arrest in an out-of-hospital setting is to call 911. Second, the witness initiates CPR (if she or he is trained in CPR). If the witness cannot initiate CPR, or the first responders of the 911 system (e.g., firefighters/police) have arrived, the first responders initiate CPR. Third, the witness or first responders apply an AED to the patient. The device reads the patient's heart rhythm and prompts for shock when indicated. Fourth, the patient is handed over to the advanced life-support team with subsequent admission to an intensive care unit in a hospital. The use of AEDs requires developing and implementing a program at sites where the cardiac arrest rate is high, where a number of potential first responders are trained and retained, and where patients are transferred to an advanced care facility after initiating resuscitation. Obviously, placing an AED at a site where no cardiac arrests are likely to occur would be futile, as would placing an AED at a site where no one knows how to use it. Moreover, abandoning patients after initial resuscitation by not transferring them to an advanced care facility would negate all earlier efforts. Thus, it is important to identify the essential components of an AED program that might also optimize the effectiveness of AED use.

METHODS

There is a large body of literature on the use of AEDs in various settings ranging from closed environments such as hospitals, airlines, and casinos to open places such as sports fields and highways. There is little doubt regarding the effectiveness and safety of AEDs to treat people in cardiac arrest. It is intuitive that these devices should be provided in hospitals in areas that are not readily accessible to the traditional responders, the "code blue team." Similarly, it is intuitive to provide AEDs in out-of-hospital settings where the risk of cardiac arrest is high and a response plan involving trained first responders in the use of AEDs is in place. Thus, the Medical Advisory Secretariat reviewed the literature and focused on the components of an AED program in out-of-hospital settings that maximize the effectiveness and cost-effectiveness of the program in the management of cardiac arrest. Search engines included MEDLINE, EMBASE, EconLit and Web sites of other agencies that assess health technologies. Any study that reported results of an AED program in an out-of-hospital setting was included. Studies that did not use AEDs, had a physician-assisted emergency response plan, did not have a program for the use of AEDs, or did not include cardiac arrest as an outcome were excluded.

SUMMARY OF FINDINGS

A total of 133 articles were identified; 62 were excluded after reviewing titles and abstracts. Of the 71 articles reviewed, 8 reported findings of 2 large studies, the Ontario Prehospital Advanced Life Support (OPALS) study and the Public Access Defibrillation (PAD) trial. These studies examined the effect of a community program to respond to cardiac arrest with and without the use of AEDs. Their authors had reported a significant reduction in overall mortality from cardiac arrest with the use of AEDs. Factors That Improve the Effectiveness of an AED Program The PAD trial investigators reported a significant improvement in survival (P = .03) after providing AEDs in public access areas and training volunteers in CPR compared with training volunteers in CPR only. The OPALS study investigators reported odds ratios (ORs) and 95% confidence intervals (CIs) for significant predictors of survival, which were age (OR [age per 10 year], 0.8; CI, 0.8-0.9), arrest witnessed by bystander (OR, 3.9; CI, 2.7-5.5), CPR initiated by bystander (OR, 3.7; CI, 2.6-5.1), CPR initiated by first responder (OR, 1.6; CI, 1.1-2.3), and emergency medical service response within 8 minutes (OR, 3.0; CI, 1.8-5.1). The last 3 variables are modifiable and thus may improve the effectiveness of an AED program. For example, the rate of bystander-initiated CPR was only 14% in the OPALS study, but it was 100% in the PAD trial. This was because PAD trial investigators trained community volunteers whereas the OPALS study investigators did not. Cost-Effectiveness A systematic review of the literature suggests that cost-effectiveness varies from setting to setting. Most of the studies have estimated cost-effectiveness in American settings from a societal perspective; therefore, the results are not applicable to this report. However, results from this review suggest that the incidence of cardiac arrest in out-of-hospital setting in Ontario is 59 per 100,000 people. The mean age of cardiac arrest patients is 69 years. Eighty-five percent of these cardiac arrests occur in homes. Of all the cardiac arrests, 37% have heart rhythm abnormalities (ventricular tachycardia or ventricular fibrillation) that are correctable by delivering shock through an AED. Thus, in an out-of-hospital setting, general use of AEDs by laypersons would not be cost-effective. Special programs are needed in the out-of-hospital setting for cost-effective use of AEDs. One model for the use of AEDs in out-of-hospital settings was examined in the OPALS study. Firefighters and police were trained and provided with AEDs. The total initial cost (in US dollars) of this program was estimated to be $980,000. The survival rate was 3.9% before implementing the AED program and 5.2% after its implementation (OR, 1.33; 95% CI, 1.03-1.7; P = .03). Applying these estimates to cardiac arrest rates in Ontario in 2002, one would expect 54 patients of the total 1,395 cardiac arrests to survive without AEDs compared with 73 patients with AEDs; thus, 19 additional lives might be saved each year with an AED program. It would initially cost $51,579 to save each additional life. In subsequent years, however, total cost would be lower (about $50,000 per year), when it would cost $2,632 to save each additional life per year. One limitation of the OPALS study was that the authors combined emergency medical service response time and application of an AED into a single variable. Thus, it was not possible to tease out the independent effects of reduction in response time and application of an AED on the small improvement in survival. Nevertheless, the PAD study found that when response time was fixed, the application of AED improved survival. There are other delivery models for AEDs in casinos, sports arenas, and airports. The proportion of cardiac arrest at these sites out of the total cardiac arrests in Ontario is between 0.05% and 0.4%. Thus, an AED placed at these sites would likely not be used at all. Of the 85% cardiac arrests that occur in homes, 56% occur in single residential dwellings (houses), 23% occur in multi-residential dwellings (apartments/condominiums), and 6% occur in nursing homes. There is no program in place except the 911 system to reach these patients. Accordingly, the Medical Advisory Secretariat examined the cost-effectiveness of providing AEDs in hospitals, office buildings, apartments/condominiums, and houses. The results suggested that deployment of AEDs in hospitals would be cost-effective in terms of cost per quality adjusted life year gained. Conversely, deployment of AEDs in office buildings, apartments, and houses was not cost-effective. An exception, however, was noted for people at high risk of sudden cardiac arrest; these were patients with a left ventricular ejection fraction less than or equal to 0.35.

CONCLUSIONS

The OPALS study model appears cost-effective, and effectiveness can be further enhanced by training community volunteers to improve the bystander-initiated CPR rates. Deployment of AEDs in all public access areas and in houses and apartments is not cost-effective. Further research is needed to examine the benefit of in-home use of AEDs in patients at high risk of cardiac arrest.

Need for differential discounting of costs and health effects in cost effectiveness analyses

The decision of the National Institute for Health and Clinical Excellence to abandon differential discounting of future health is a step backwards and could change funding decisions