Is the survival rate in ‘sudden death’ cardiac patients increased
when automated external defibrillators are used?
Introduction
Synthesis of Literature: Studies 1, 2, 3, 4 & 5
- Aim of study
- Methodology
- Results
- Conclusion
Synthesis and Relevance to Research topic
Conclusion
- Summary Table
Is the survival rate in ‘sudden death’ cardiac patients increased
when automated external defibrillators are used?
Introduction
This literature review encompasses five studies relating evidence based practice regarding survival rates in ‘sudden death’ cardiac patients. These rates would be examined in relation to the use automated external defibrillators. Assessments of the research aims, methodology, results/ conclusions will be embraced.
Synthesis of Literature
Study 1
Aim
Comilla Sasson; Mary A.M. Rogers; Jason Dahl and Arthur L. Kellermann (2009) conducted a systemic review and Meta-Analysis pertaining to ‘Predictors of Survival from Out-of-Hospital Cardiac Arrest.’ The aim of this study was to evaluate the strength of associations between OHCA and key factors. These key factors were related to event witnessed by a bystander or emergency medical services (EMC). Also, provision of bystander cardiopulmonary resuscitation (CPR) as well as initial cardiac rhythm and return of spontaneous circulation were assessed. The researchers were also interested in examining out-of- hospital cardiac arrest (OHCA) survival trends over time (Sasson, Rogers; Dahl and Kellermann, 2010).
Methodology
The researchers conducted electronic searches of PubMed, EMBASE, Web of Science, CINAHL, Cochrane DSR, DARE, ACP Journal Club, and CCTR between January 1, 1950 and August 21, 2008. These searches sought to identify out-of hospital cardiac arrest (OHCA) of presumed cardiac etiology in adult clients. They retrieved data from 79 studies involving 142,740 patients. Data was analyzed using meta-analysis. Heterogeneity was calculated by applying Cochran’s Q test and I squared. The degree of inconsistency among studies, were also calculated. Publication bias was calculated using Begg’s test and a visual inspection of the funnel plot. Meta-regression was further applied to heterogeneity in exploring ratio odds. Essentially, variables measured were heart arrest; heart, sudden; emergency medical services along with witnessed by bystander; witnessed by EMS; bystander CPR; Ventricular Fibrillation/Ventricular Tachycardia; asystole; return of spontaneous circulation and number needed to treat to save one life (Sasson et.al, 2010).
Results
Thirty-six studies were reported to have had enough data for evaluating an association of OHCA witnessed by a bystander. Collectively, these outcomes represented 95 539 of cases reviewed. In these studies, the crude rate of survival to hospital discharge was 7.6% (7214 survivors). From thirty articles enough data was accessed in determining an association between OHCA being witnessed by EMS personnel and survival. 83 229 cases, with a crude overall survival rate to hospital discharge rate of 6.1% (5056 survivors) were reported (Sasson et.al, 2010).
Meta-regression analyses revealed that only baseline survival was significantly related to heterogeneity in odds ratio. Additionally these results of the weighted multivariate linear regression indicated that baseline survival significantly explained differences in survival rates. Sensitivity analysis was limited to adult cardiac arrest patients for whom resuscitation was attempted in the pre-hospital setting. Due to the importance of a consistent denominator, ‘total number of resuscitations attempted in the pre-hospital setting’ the analysis excluded four studies. that described patients who sustained OHCA. It did not include information on patients who were treated and not transported to the emergency department. Consequently, it was proven that excluding these studies did not significantly alter the final pooled results. In concluding, for all 5 criteria of interest, the Begg test was not significant (P₃0.05) because visual inspection of funnel plots did not suggest publication bias (Sasson et.al, 2010).
Conclusion
There has been marked improvement in survival rates of out- of- hospital cardiac arrest (OHCA) cases over the past 30 years. Aggregate survival rate, is between 6.7% and 8.4% for populations among diverse population. Use of novel drugs and devices, periodic evidence-based revisions to clinical practice guidelines may be instrumental in reducing ventricular fibrillation arrests (Sasson et.al, 2010).
Study 11
Aim
Leigh M. Smith; Patricia M. Davidson; Elizabeth J. Halcomb and Sharon Andrew (2007) ask the question, Can lay responder defibrillation programme improve survival to hospital discharge following an out-of-hospital cardiac arrest? Their aim was to critically review literature, which evaluates the ‘impact of lay responder defibrillator programs on survival to hospital discharge following an out-of-hospital cardiac arrest in the adult population’ (Smith, Davidson, Halcomb and Andrew, 2007).
Methodology
Researchers utilized electronic databases, Medline and CINAHL applying keywords ‘‘first responder’’, ‘‘lay responder’’, ‘‘defibrillation’’ and ‘‘cardiac arrest’’ to the search for suitable literature. Only primary data articles were selected for this study. Also the had to be written in English describing effects ‘of a lay responder defibrillation program on survival to hospital discharge from out-of-hospital cardiac arrest in adults’ ( Smith et.al, 2007).
Results
Eleven articles met the inclusion criteria from the databases reviewed. Heterogeneity of populations studied as well as study outcome methods limited formal meta-analysis from the small sample that was withdrawn. As such, narrative analysis had to be the main mode of interpreting data. It was revealed that these studies, however, were inadequate in providing consistent findings related to hospital survival discharge rates following out-of-hospital cardiac arrest (Smith et.al, 2007).
Conclusion
Despite these astounding results, it could be concluded from the small data package reviewed that lay responder play an important role in improving the outcome from out-of-hospital cardiac arrest following early defibrillation. There were obvious methodological difficulties studying this population. Therefore, recommendations are for future research with the aim of addressing outcomes related to morbidity, mortality and cost-effectiveness (Smith et.al, 2007).
Study 111
Aim
Sanna, La Torre, de Waure, Scapigliati, Ricciardi, Russo, Pelargonio, Casella and Bellocci (2007) engaged in research investigating ‘Cardiopulmonary resuscitation alone vs. cardiopulmonary resuscitation plus automated external defibrillator use by non-healthcare professionals: A meta-analysis on 1583 cases of out-of-hospital cardiac arrest.’ The aim was to ‘perform a systematic review and a meta-analysis of the pooled effect of studies comparing the outcome of pts receiving cardiopulmonary resuscitation plus AED therapy (CPR + AED) vs. cardiopulmonary resuscitation (CPR) alone, both delivered by non-healthcare professionals, for the treatment of OHCA’ (Sanna, La Torre, de Waure, Scapigliati, Ricciardi, Russo, Pelargonio, Casella & Bellocci, 2007).
Methodology
These researchers conducted a search for relevant literature from scientific databases, which contained journals, analyzing conference proceedings, abstracts as well as discussing issues pertinent to the topic explored by more matured researchers. Survival to hospital admission and survival to hospital discharge were the areas of interest in the search analysis (Sanna et.al, 2007).
Results
Meta-analysis was conducted on three studies. First meta-analysis showed a RR of 1.22 (95% C.I.: 1.04—1.43) of surviving to hospital admission for people treated with CPR + AED as compared to CPR-only. A second meta-analysis revealed a RR of 1.39 (95% C.I.: 1.06—1.83) of surviving to hospital discharge for people treated with CPR + AED as compared to CPR-only (Sanna et.al, 2007).
Conclusions
Results were consistent with current trends of evidence base interventions. CPR plus early fibrillation programs along with AEDs trained non-healthcare professional ones offered a greater survival rate above CPR-only in OHCA (Sanna et.al, 2007).
Study 1V
Aim
Kenward, Castle and Hodgetts (2002) conducted a systemic review of primary research to find out whether ‘ward nurses should be using automatic external defibrillators as first responders to improve the outcome from cardiac arrest?’ They focused on locating and evaluating evidence to support automatic external defibrillator use in-hospital on general wards (Kenward et.al, 2002).
Methodology
A systemic review of indexed grey literature was the method adapted by researchers to investigate the question under review (Kenward et.al, 2002).
Results
Researchers reported that 15 in-hospital automatic external defibrillator studies were located, but only five met the inclusion criteria (Kenward et.al, 2002).
Conclusions
Evidently, the sample of literature retrieved was inadequate to assess the extent to which automatic external defibrillators in-hospital were effective. However, it was discovered that manual defibrillators were the most common devices used for in-hospital defibrillation. The alternative was automatic external defibrillators. These devices contained a screen and manual override capability. Researchers cited that in order for automatic external defibrillator programs to be effective in service education must be done to adjust the philosophy by which it is presently utilized in hospitals (Kenward et.al, 2002).
Study V
Aim
Chan, Harlan, Krumholz, Spertus, Jones, Cram, Berg, Peberdy, Nadkarni, Mancini and Nallamothu (2010) investigated ‘Automated External Defibrillators and Survival After In-Hospital Cardiac Arrest’ with the aim of evaluating the association between automated external defibrillation(AED) use and survival for in-hospital cardiac arrest.
Methodology
Researchers used a cohort study ‘design of 11 695 hospitalized patients with cardiac arrests between January 1, 2000, and August 26, 2008, at 204 US hospitals following the introduction of AEDs on general hospital wards’( Chan, Harlan, Krumholz, Spertus, Jones, Cram, Berg, Peberdy, Nadkarni, Mancini & Nallamothu, 2010).
Results
Findings of this study revealed that AED use was associated with a lower rate of survival after in-hospital cardiac arrest compared with no AED use (16.3% vs 19.3%; adjusted rate ratio. Among cardiac arrests due to nonshockable rhythms, AED use was associated with lower survival (10.4% vs 15.4%; adjusted RR, 0.74; 95% CI, 0.65-0.83; P < .001). In contrast, for cardiac arrests due to shockable rhythms, AED use was not associated with survival (38.4% vs 39.8%; adjusted RR, 1.00; 95% CI, 0.88-1.13; P = .99) ( Chan et.al, 2010)
Conclusion
When relating the use of automatic external defibrillators (AEDs) to hospitalized patients with cardiac arrest there was no improvement in the survival rate (Chan et.al, 2010).
Synthesis and Relevance to Research topic
The foregoing research studies explored the extent to which survival rate in ‘sudden death’ cardiac patients increased when automated external defibrillators were used. It was clearly highlighted from the last cohort study conducted by Chan (2010) and counterparts that with hospitalized patients there were no marked increases in survival rates when automatic external defibrillators were used in cardiac arrest cases. However, while this was supported in the Kenward’s (2002) literature review the conclusion was that in order for automatic external defibrillator programs to be effective in-service education must be done to adjust the philosophy by which it is presently utilized in hospitals (Kenward et.al, 2002).
Subsequently, the other three previous studies cited in this review of the literature presentation focused on out-of hospital cardiac arrest (OHCA) survival rates when a number of variables including automatic external defibrillation were applied. Sasson‘s (2010)’ meta-analysis of literature showed marked improvement is survival rates within the past thirty years. This was attributed to applications of evidence passed practice intervention and use of modern devices. These researchers did not specify what those devices were (Sasson et.al, 2010) .
More intently Smith’s (2007) team of researchers sought to determine whether a lay responder defibrillation programme could improve survival to hospital discharge following an out-of-hospital cardiac arrest. They found that with the limited literature retrieved on the subject that lay responders play an important role in improving the outcome from out-of-hospital cardiac arrest following early defibrillation (Smith et.al, 2007).
Sanna (2007) and counterparts comprehensively concluded that CPR plus early fibrillation programs along with AEDs trained non-healthcare professional offered a greater survival rate above CPR-only in OHCA (Sanna et.al, 2007). Hence, these pieces of literature have clearly identified the extent to which survival rate in ‘sudden death’ cardiac patients increased when automated external defibrillators were used.
Conclusion
Summary Table
References
Chan, P. Harlan, H. Krumholz, J. Spertus, Jones, P. Cram,P. Berg, R. Peberdy, M. Nadkarni,V.
Mancini, M., & Nallamothu, B. (2010). Automated External Defibrillators and Survival
After In-Hospital Cardiac Arrest. JAMA, 304(19),2129-2136
Sanna, T. La Torre, G. de Waure, C. Scapigliati,A. Ricciardi,W. Russo, A. Pelargonio,G.
Casella,M., & Bellocci, F. (2007). Cardiopulmonary resuscitation alone vs.
cardiopulmonary resuscitation plus automated external defibrillator use by non-healthcare
professionals: A meta-analysis on 1583 cases of out-of-hospital cardiac arrest.
Resuscitation, 76, 226—232
Sasson, C. Rogers, M. Dahl, J., & Kellermann, A. (2010). Predictors of Survival From Out-of-
Hospital Cardiac Arrest: A Systematic Review and Meta-Analysis. Circ Cardiovasc Qual
Outcomes. Retrieved on 1st February, 2012 from http://circoutcomes.ahajournals.org
Smith, L. Davidson, P. Halcomb, E., & Andrew, S. (2007). Can lay responder defibrillation
programes improve survival to hospital discharge following an out-of-hospital
cardiac arrest? Australian Critical Care, 20, 137—145
Kenward, G. Castle, N., & Hodgetts, J. (2002). Should ward nurses be using automatic external
defibrillators as first responders to improve the outcome from cardiac arrest? A
systematic review of the primary research. Elsevier Science Ireland Ltd
