Strategies to improve survival outcomes of out-of-hospital cardiac arrest (OHCA) given a fixed budget: A simulation study

A Systematic Review of Cost-Effectiveness of Treating Out of Hospital Cardiac Arrest: Implications for Resource-limited Health Systems

Background

Out-of-hospital cardiac arrest (OHCA) is a prevalent condition with high mortality and poor outcomes even in settings where extensive emergency care resources are available. Interventions to address OHCA have had limited success, with survival rates below 10% in national samples of high-income countries. In resource-limited settings, where scarcity requires careful priority setting, more data is needed to determine the optimal allocation of resources.

Objective

To establish the cost-effectiveness of OHCA care and assess the affordability of interventions across income settings.

Methods

The authors conducted a systematic review of economic evaluations on interventions to address OHCA. Included studies were (1) economic evaluations (beyond a simple costing exercise); and (2) assessed an intervention in the chain of survival for OHCA. Article quality was assessed using the CHEERs checklist and data summarised. Findings were reported by major themes identified by the reviewers. Based upon the results of the cost-effectiveness analyses we then conduct an analysis for the progressive realization of the OHCA chain of survival from the perspective of decision-makers facing resource constraints.

Results

468 unique articles were screened, and 46 articles were included for final data abstraction. Studies predominantly used a healthcare sector perspective, modeled for all patients experiencing non-traumatic cardiac OHCA, were based in the US, and presented results in US Dollars. No studies reported results or used model inputs from low-income settings. Progressive realization of the chain of survival could likely begin with investments in TOR protocols, professional prehospital defibrillator use, and CPR training followed by distribution of AEDs in high-density public locations. Finally, other interventions such as indiscriminate defibrillator placement or adrenaline use, would be the lowest priority for early investment.

Conclusion

Our review found no high-quality evidence on the cost-effectiveness of treating OHCA in low-resource settings. Existing evidence can be utilized to develop a roadmap for the development of a cost-effective approach to OHCA care, however further economic evaluations using context-specific data are crucial to accurately inform prioritization of scarce resources within emergency care in these settings.

Outcome assessment for out-of-hospital cardiac arrest patients in Singapore and Japan with initial shockable rhythm

BACKGROUND

Singapore and Osaka in Japan have comparable population sizes and prehospital management; however, the frequency of ECPR differs greatly for out-of-hospital cardiac arrest (OHCA) patients with initial shockable rhythm. Given this disparity, we hypothesized that the outcomes among the OHCA patients with initial shockable rhythm in Singapore were different from those in Osaka. The aim of this study was to evaluate the outcomes of OHCA patients with initial shockable rhythm in Singapore compared to the expected outcomes derived from Osaka data using machine learning-based prediction models.

METHODS

This was a secondary analysis of two OHCA databases: the Singapore PAROS database (SG-PAROS) and the Osaka-CRITICAL database from Osaka, Japan. This study included adult (18-74 years) OHCA patients with initial shockable rhythm. A machine learning-based prediction model was derived and validated using data from the Osaka-CRITICAL database (derivation data 2012-2017, validation data 2018-2019), and applied to the SG-PAROS database (2010-2016 data), to predict the risk-adjusted probability of favorable neurological outcomes. The observed and expected outcomes were compared using the observed-expected ratio (OE ratio) with 95% confidence intervals (CI).

RESULTS

From the SG-PAROS database, 1,789 patients were included in the analysis. For OHCA patients who achieved return of spontaneous circulation (ROSC) on hospital arrival, the observed favorable neurological outcome was at the same level as expected (OE ratio: 0.905 [95%CI: 0.784-1.036]). On the other hand, for those who had continued cardiac arrest on hospital arrival, the outcomes were lower than expected (shockable rhythm on hospital arrival, OE ratio: 0.369 [95%CI: 0.258-0.499], and nonshockable rhythm, OE ratio: 0.137 [95%CI: 0.065-0.235]).

CONCLUSION

This observational study found that the outcomes for patients with initial shockable rhythm but who did not obtain ROSC on hospital arrival in Singapore were lower than expected from Osaka. We hypothesize this is mainly due to differences in the use of ECPR.

Out-of-Hospital Cardiac Arrest Bystander Defibrillator Search Time and Experience With and Without Directional Assistance: A Randomized Simulation Trial in a Community Setting

INTRODUCTION

Probability of survival after out-of-hospital cardiac arrest (OHCA) doubles when a bystander initiates cardiopulmonary resuscitation and uses an automated external defibrillator (AED) rapidly. National, state, and community efforts have increased placement of AEDs in public spaces; however, bystander AED use remains less than 2% in the United States. Little is known about the effect of giving bystanders directional assistance to the closest public access AED.

METHODS

We conducted 35 OHCA simulations using a life-sized manikin with participants aged 18 through 65 years who searched for public access AEDs in 5 zones on a university campus. Zones varied by challenges to pedestrian AED acquisition and number of fixed AEDs. Participants completed 2 searches-first unassisted and then with verbal direction to the closest AED-and we compared AED delivery times. We conducted pretest and posttest surveys.

RESULTS

In all 5 zones, the median time from simulated OHCA onset to AED delivery was lower when the bystander received directional assistance. Time savings (minutes:seconds) varied by zone, ranging from a median of 0:53 (P = 0.14) to 3:42 (P = 0.02). Only 3 participants immediately located the closest AED without directional assistance; more than half reported difficulty locating an AED.

CONCLUSIONS

These findings may inform strategies to ensure that AEDs are consistently marked and placed in visible, accessible locations. Continued emphasis on developing strategies to improve lay bystanders' ability to locate and use AEDs may improve AED retrieval times and OHCA outcomes.

Transportation during and after cardiac arrest: who, when, how and where?

PURPOSE OF REVIEW

Out-of-hospital cardiac arrest (OHCA) is the most devastating and time-critical medical emergency. Survival after OHCA requires an integrated system of care, of which transport by emergency medical services is an integral component. The transport system serves to commence and ensure uninterrupted high-quality resuscitation in suitable patients who would benefit, terminate resuscitation in those that do not, provide critical interventions, as well as convey patients to the next appropriate venue of care. We review recent evidence surrounding contemporary issues in the transport of OHCA, relating to who, where, when and how to transport these patients.

RECENT FINDINGS

We examine the clinical and systems-related evidence behind issues including: contemporary approaches to field termination of resuscitation in patients in whom continued resuscitation and transport to hospital would be medically futile, OHCA patients and organ donation, on-scene versus intra-transport resuscitation, significance of response time, intra-transport interventions (mechanical chest compression, targeted temperature management, ECMO-facilitated cardiopulmonary resuscitation), OHCA in high-rise locations and cardiac arrest centers. We highlight gaps in current knowledge and areas of active research.

SUMMARY

There remains limited evidence to guide some decisions in transporting the OHCA patient. Evidence is urgently needed to elucidate the roles of cardiac arrest centers and ECPR in OHCA.

Community Variations in Out-of-Hospital Cardiac Arrest Care and Outcomes in Texas

Background: Large and unacceptable variation exists in cardiac resuscitation care and outcomes across communities. Texas is the second most populous state in the US with wide variation in community and emergency response infrastructure. We utilized the Texas-CARES registry to perform the first Texas state analysis of out-of-hospital cardiac arrest (OHCA) in Texas, evaluating for variations in incidence, care, and outcomes.Methods: We analyzed the Texas-CARES registry, including all adult, non-traumatic OHCAs from 1/1/2014 through 12/31/2018. We analyzed the incidence and characteristics of OHCA care and outcome, overall and stratified by community. Utilizing mixed models accounting for clustering by community, we characterized variations in bystander CPR, bystander AED in public locations, and survival to hospital discharge across communities, adjusting for age, gender, race, location of arrest, and rate of witnessed arrest (bystander and 911 responder witnessed).Results: There were a total of 26,847 (5,369 per year) OHCAs from 13 communities; median 2,762 per community (IQR 444-2,767, min 136, max 9161). Texas care and outcome characteristics were: bystander CPR (43.3%), bystander AED use (9.1%), survival to discharge (9.1%), and survival with good neurological outcomes (4.0%). Bystander CPR rate ranged from 19.2% to 55.0%, and there were five communities above and five below the adjusted 95% confidence interval. Bystander AED use ranged from 0% to 19.5%, and there was one community below the adjusted 95% confidence interval. Survival to hospital discharge ranged from 6.7% to 14.0%, and there were three communities above and two below the adjusted 95% confidence interval.Conclusion: While overall OHCA care and outcomes were similar in Texas compared to national averages, bystander CPR, bystander AED use, and survival varied widely across communities in Texas. These variations signal opportunities to improve OHCA care and outcomes in Texas.

Community disparities in out of hospital cardiac arrest care and outcomes in Texas

BACKGROUND

Large racial and socioeconomic inequalities exist for out-of-hospital cardiac arrest (OHCA) care and outcomes. We sought to characterize racial, ethnic, and socioeconomic disparities in OHCA care and outcomes in Texas.

METHODS

We analyzed 2014-2018 Texas-Cardiac Arrest Registry to Enhance Survival (CARES) data. Using census tracts, we defined race/ethnicity neighborhoods based on majority race/ethnicity composition: non-Hispanic/Latino white, non-Hispanic/Latino black, and Hispanic/Latino. We also stratified neighborhoods into socioeconomic categories: above and below the median for household income, employment rate, and high school graduation. We defined outcomes as bystander CPR rates, public bystander AED use, and survival to hospital discharge. Using mixed models, we analyzed the associations between outcomes and neighborhood (1) racial/ethnic categories and (2) socioeconomic categories.

RESULTS

We included data on 18,488 OHCAs. Relative to white neighborhoods, black neighborhoods had lower rates of AED use (OR 0.3, CI 0.2-0.4), and Hispanic/Latino neighborhoods had lower rates of bystander CPR (OR 0.7, CI 0.6-0.8), AED use (OR 0.4, CI 0.3-0.6), and survival (OR 0.8, CI 0.7-0.8). Lower income was associated with a lower rates of bystander CPR (OR 0.8, CI 0.7-0.8), AED use (OR 0.5, CI 0.4-0.8), and survival (OR 0.9, CI 0.9-0.98). Lower high school graduation was associated with a lower rate of bystander CPR (OR 0.8, CI 0.7-0.9) and AED use (OR 0.6, CI 0.4-0.9). Higher unemployment was associated with lower rates of bystander CPR (OR 0.9, CI 0.8-0.94) and AED use (OR 0.7, CI 0.5-0.99).

CONCLUSION

Minority and poor neighborhoods in Texas experience large and unacceptable disparities in OHCA bystander response and outcomes.

Does time of day influences outcome in out-of-hospital cardiac arrest patients?: A meta-analysis of cohort studies

BACKGROUND

Whether time of day has impact on outcomes after out-of-hospital cardiac arrest (OHCA) remains controversial. However, there are no evidence syntheses describing the impact of time differences on outcomes from OHCA.

METHODS

A meta-analysis of cohort studies exploring the association between time of day and survival in patients with OHCA was performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using a random-effects model.

RESULTS

Ten studies involving 252,848 patients and 24,646 survivals were included. Patients with night-time OHCA had significantly lower short-term survival compared to patients with daytime OHCA (OR, 1.20; 1.07-1.36; P < .001). The relationship between temporal differences and survival was consistent in most subgroups. For long-term survival, it remained unclear whether night-time was associated with reduced OHCA survival at 12 months (OR, 1.47; 0.71-3.06; P < .001). Three studies including 183,129 patients examined the association between weekend and survival in OHCA patients. Survival did not differ on weekends compared to weekdays (OR, 1.00; 0.9 7-1.04; P = .918).

CONCLUSIONS

Night-time is associated with a lower survival in OHCA patients. However, similar findings are not observed in OHCA patients on weekends. Caution is required in interpretation of these results accounting for high level of heterogeneity and large, well designed, randomized trials are warranted.