An observational study in Cardiac Arrest, Sudden, Ventricular Tachycardia and Ventricular Fibrillation, sponsored by French Defence Health Service. Completed at 1 site in France. Open to participants aged 12 Years and older. Per ClinicalTrials.gov, last updated 2024-05-30.
Sponsored by French Defence Health Service · Observational
In the Paris (France) Medical Emergency system, in the early phase of Out-of-hospital Cardiac Arrest (OHCA), the treatment of a Ventricular Fibrillation (VF) consists of delivering an External Electric Shock (EES) by a rescuer with the use of an Automated External Defibrillator (AED). This latter realizes a cardiac rhythm analysis every two minutes. This analysis requires that chest compressions (CC) be interrupted for a while. However, CC interruptions are potentially harmful due to the brain, and heart perfusions decrease.
On the other hand, the recurrence of VF occurs mostly during the first minute after the shock, whereas the delay between 2 rhythm analysis is 2 minutes. The consequence is excessive time spent in VF, which is deleterious in terms of coronary and cerebral perfusion.
The investigator implements a new AED algorithm whose operating principle is as follows. One minute after an EES administration, the AED realizes a cardiac rhythm analysis during which the rescuers do not need to interrupt the chest compressions (CC): this is called the rhythm analysis " in presence of CC" The detection of a VF " in presence of CC " needs to be confirmed, " in absence of CC " The CC's are therefore interrupted for new rhythm analysis. Once the presence of VF is approved, the AED proposes a shock to be administred
The aim of the study
Study Design:
This is a prospective observational study.
The eligibility criteria are as follows:
The primary endpoint is the " chest-compression fraction (CCF) " that represents the CPR-time performance during the ten first minutes of BLS care ( or \< 10 min in case of Return Of Spontaneus Circulation (ROSC))
BACKGROUND
For Out-Of-Hospital Cardiac Arrest (OHCA) patients suffering from ventricular fibrillation (VF) or ventricular tachycardia (VT), BLS care consists of administering external electric shocks (EES) and cardiopulmonary resuscitation (CPR). However, despite successful defibrillation, VF recurs in 50% of cases. Rescuers are forced to repeat EES as often as needed, without the recommendations specifying a maximum number.
International guidelines recommend a 2-min CPR time between 2 rhythm analysis, that means one shock every 2 min. Since refibrillation occurs mostly during the first-minute post-shock, the patient will have to wait until the end of the 2 minutes before receiving the next EES. During that time, the chest compressions (CC) provide a reduced fraction of physiologic blood flow.
The new AED algorithm provides the following changes :
This new algorithm fits in between two historical CPR algorithms used in western medical systems - the one-minute and the two-minute CPR cycle- depending on the rhythm shockability detected " in presence of CC "
OBJECTIVES
The main objective is to measure the " CC fraction " during the ten first minutes of Fire Fighter BLS care in OHCA.
The secondary objectives :
METHOD
This is a prospective observational study.
The study does not imply any change in current practice. There is no planned interim analysis.
All consecutive participants with inclusion criteria and no exclusion criteria will be analyzed.
STUDY SIZE
The sample size was calculated to perform a non-inferiority analysis first, followed by a superiority test if non-inferiority was demonstrated.
Non-inferiority test. The formula for calculating the required sample size in each group is based on a well-established statistical methodology designed for comparing two means in the context of a non-inferiority test.
n = ((Z α/2 + Z β)2 X (σ12 + σ22)) / (μ1- μ2 - δ)2
With:
After the calculations, the required sample size was 208 subjects for each group involved in the non-inferiority testing.
Superiority test. Should the non-inferiority hypothesis not be rejected, the study design allows for a subsequent superiority test to be conducted.
For superiority, the investigators use the formula :
n = ((Z α/2 + Z β)2 X (σ12 + σ22)) / (μ1- μ2)2
With:
For α risk = 0.025 (Bonferroni correction), a power established at 90%, a standard deviation of 17, and a detectable difference between the two groups of 5%, the required sample size was 256 subjects for each group involved in the superiority testing. (STATA : sampsi 65 70 ,SD(17) alpha(0.025)) To account for a 10% loss of subjects, the number of patients was increased to 282, rounded up to 285 per group, i.e., a total of 570 patients.
To observe 285 shockable patients, the investigators estimate the observation time required to be one year.
Note that this same number of patients will be sufficient to detect an absolute 10% difference with an alpha risk of 5% and a power of 90%, between patients in the "2017" group and patients in the "2020" group with regard to the secondary endpoint "Survival at hospital admission"
INTERRUPTION OR STOPPING OF THE STUDY
The sponsor has the responsibility to report, to the national health authority, any serious and unexpected adverse events attributable to the new AED algorithm.
RISKS
A full report on the risks, the description of incidents, accidents and adverse events will be the subject of a chapter in the results section and also in the discussion.
FINANCING
Funding for the study is provided by the Paris Fire Brigade (promoter, following acceptance of the survey under French policy for clinical research projects)
DISCUSSION
The study will report on the CC fraction of an AED algorithm designed to analyze "under CC."
966 studies on the registry are indexed under Heart Arrest; 226 are open to participants now.
This study's enrollment of 285 is above the median of 200 across 382 observational studies indexed under Heart Arrest.
Browse Heart Arrest studies →French Defence Health Service is the lead sponsor of 4 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
Medical OHCA patients of the greater Paris (Paris, Haut-de-Seine, Seine-Saint-Denis and Val- de-Marne Country)
-Non-traumatic OHCA in adults, treated by a BLS team and connected to an AED equipped either with the 2017 or with the 2020 algorithm.
Exclusion Criteria:
Secondary Exclusion Criteria
Report on Chest Compression Fraction (CCf)
CCf is the length of time the patient receives chest compression/management time (describe as a %)
Time frame: 10 minutes
Report on Cardiopulmonary Resuscitation (CPR) parameters : CPR ratio
CPR ratio (time during which the patient receives chest compression and bag ventilation / total management time; describe as a %)
Time frame: 10 minutes
Report on Cardiopulmonary Resuscitation (CPR) parameters :Prompt CPR fraction
Prompt CPR fraction (duration between the two AED announcements "resume massage" and "interrupt massage"/ total management time; describe as a %)
Time frame: 10 minutes
Report on Cardiopulmonary Resuscitation (CPR) parameters:Maximal Hands-Off time
Maximal Hands-Off time (longest time frame without any CC; describe in seconds)
Time frame: 10 minutes
Report on Cardiopulmonary Resuscitation (CPR) parameters:Chest Compression Frequency
Chest Compression Frequency (i.e., measurement of the mobile frequency over 3 to 5 compressions; describe as number of chest compressions by minute)
Time frame: 10 minutes
Report on the diagnostic performance of the AED algorithms "during CC" and " in absence of CC"
Calculate Sensibility and Specificity
Time frame: 10 minutes
Report on the overall diagnostic performance resulting from the combination of the consecutive analyses " in presence of CC " and " in absence of CC"
Calculate Sensibility and Specificity
Time frame: 10 minutes
Report on five-second-post-shock rhythms and their incidence
asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation for "in absence of CC" analysis, at 5 seconds
Time frame: 10 minutes
Report on 60-second-post-shock rhythms and their incidence
asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation for "in absence of CC" analysis, at 60 seconds
Time frame: 10 minutes
Report on 120 second-post-shock rhythms and their incidence
asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation for "in absence of CC" analysis, at 120 seconds
Time frame: 10 minutes
Report on 15-second-post-shock rhythms and their incidence
asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation for "in absence of CC" analysis, at 15 seconds
Time frame: 10 minutes
Report on 30-second-post-shock rhythms and their incidence
asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation for "in absence of CC" analysis, at 30 seconds
Time frame: 10 minutes
Report on the number of electrical shocks (EES) delivered and the duration of the rhythmic storm
Total number of EES delivered (describe as a number)
Time frame: 1 hour
Report on the number of electrical shocks (EES) intended and the duration of the rhythmic storm
Ratio "number of EES intended / number of EES delivered" (describe as a ratio %)
Time frame: 1 hour
Report on the temporal distribution of electrical shocks (EES) and the duration of the rhythmic storm
EES temporal distribution per patient
Time frame: 1 hour
Report on the delay from start to end of cumulative VF episodes
The time period from the start of the first occurence of VF to to the ending of the last episode of ventricular fibrillation (VF) ( seconds)
Time frame: 1 hour
The time period from the AED-switch-on and the first EES (describe in seconds)
The time period from the AED-switch-on and the first EES (describe in seconds)
Time frame: 1 hour
The distribution over time of EES.
The distribution over time of EES.
Time frame: 1 hour
Outcomes - ROSC
Return Of Spontaneous Circulation (ROSC) (describe as a ratio of patients with ROSC / patients included)
Time frame: 2 hours
Outcomes - admitted alive at hospital
Survival to hospital admission (describe as a ratio of patients admitted beating heart to hospital / patients included)
Time frame: 2 hours
Outcomes - discharged from hospital
Survival at hospital discharge (describe as a ratio of patients discharged alive from hospital / patients included)
Time frame: 1 month
Compare Chest Compression Fraction (CCf) to Paris Fire Brigade 2017 historical data
CCf is the length of time the patient receives chest compression/management time (describe as a %)
Time frame: 10 minutes
Prompt CPR fraction (duration between the two AED announcements "resume massage" and "interrupt massage"/ total management time; describe as a %)
Prompt CPR fraction (duration between the two AED announcements "resume massage" and "interrupt massage"/ total management time; describe as a %)
Time frame: 10 minutes
CPR ratio (time during which the patient receives chest compression and bag ventilation / total management time; describe as a %)
CPR ratio (time during which the patient receives chest compression and bag ventilation / total management time; describe as a %)
Time frame: 10 minutes
Maximal Hands-Off time (longest time frame without any CC; describe in seconds)
Maximal Hands-Off time (longest time frame without any CC; describe in seconds)
Time frame: 10 minutes
Chest Compression Frequency (i.e., measurement of the mobile frequency over 3 to 5 compressions; describe as number of chest compressions by minute)
Chest Compression Frequency (i.e., measurement of the mobile frequency over 3 to 5 compressions; describe as number of chest compressions by minute)
Time frame: 10 minutes
Compare Sensibility and Specificity of AED algorithm "during CC" and "in absence of CC" to 2017 algorithm Sensibility and Specificity
Compare Sensibility and Specificity of AED algorithm "during CC" and "in absence of CC" to 2017 algorithm Sensibility and Specificity
Time frame: 10 minutes
Compare the overall diagnostic performance resulting from the combination of the consecutive analyses " in presence of CC " and " in absence of CC" to Paris Fire Brigade 2017 historical data
Compare the overall diagnostic performance resulting from the combination of the consecutive analyses " in presence of CC " and " in absence of CC" to Paris Fire Brigade 2017 algorithm Sensibility and Specificity
Time frame: 10 minutes
Compare post-shock rhythms and their incidence to Paris Fire Brigade 2017 historical data
Compare asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation incidence for "in presence of CC" analysis, at 5 seconds to Paris Fire Brigade 2017 differents rhythms incidences.
Time frame: 10 minutes
Compare post-shock rhythms and their incidence to Paris Fire Brigade 2017 historical data
Compare asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation incidence for "in absence of CC" analysis, at 60 seconds to Paris Fire Brigade 2017 differents rhythms incidences.
Time frame: 10 minutes
Compare post-shock rhythms and their incidence to Paris Fire Brigade 2017 historical data
Compare asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation incidence for "in absence of CC" analysis, at 120 seconds to Paris Fire Brigade 2017 differents rhythms incidences.
Time frame: 10 minutes
Compare post-shock rhythms and their incidence to Paris Fire Brigade 2017 historical data
Compare asystole, pulseless electrical activity, ventricular tachycardia, ventricular fibrillation incidence for "in absence of CC" analysis, at 5 seconds to Paris Fire Brigade 2017 differents rhythms incidences.
Time frame: 10 minutes
Compare number of electrical shocks (EES) and the duration of the rhythmic storm to Paris Fire Brigade 2017 historical data
Total number of EES delivered (describe as a number) compare to Paris Fire Brigade 2017 historical data
Time frame: 10 minutes
Compare number of electrical shocks (EES) and the duration of the rhythmic storm to Paris Fire Brigade 2017 historical data
EES temporal distribution per patient compare to Paris Fire Brigade 2017 historical data
Time frame: 10 minutes
Compare number of electrical shocks (EES) and the duration of the rhythmic storm to Paris Fire Brigade 2017 historical data
The time period from the start of the first to the end of the last ventricular fibrillation (VF) episode (describe in seconds) compare to Paris Fire Brigade 2017 historical data
Time frame: 10 minutes
Compare number of electrical shocks (EES) and the duration of the rhythmic storm to Paris Fire Brigade 2017 historical data
The time period from the AED-switch-on and the first EES (describe in seconds) compare to Paris Fire Brigade 2017 historical data
Time frame: 10 minutes
Compare number of electrical shocks (EES) and the duration of the rhythmic storm to Paris Fire Brigade 2017 historical data
Compare the distribution over time of EES.to Paris Fire Brigade 2017 historical data
Time frame: 10 minutes
Outcomes - ROSC
Compare return Of Spontaneous Circulation (ROSC) to Paris Fire Brigade 2017 historical data (describe as a ratio of patients with ROSC / patients included)
Time frame: 1 hour
Outcomes - admitted alive at hospital
Compare survival to hospital admission to Paris Fire Brigade 2017 historical data (describe as a ratio of patients admitted beating heart to hospital / patients included)
Time frame: 2 hours
Outcomes - hospital discharge
Compare survival at hospital discharge to Paris Fire Brigade 2017 historical data (describe as a ratio of patients discharged alive from hospital / patients included)
Time frame: 1 month
Plan to share: No
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French Defence Health Service