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PubMed1984

Self-adhesive preapplied electrode pads for defibrillation and cardioversion.

The efficacy of self-adhesive electrode pads for defibrillation and cardioversion was assessed in 80 patients who received 267 shocks from self-adhesive pads. In all but two patients, defibrillation or cardioversion was achieved at least once. The pads were equally effective when used in the apex-anterior or apex-posterior position. The transthoracic impedance using self-adhesive pads was 75 +/- 21 ohms (mean +/- standard deviation), which is similar to previously reported transthoracic impedance in defibrillation, using standard hand-held electrode paddles of 67 +/- 36 ohms. It is concluded that self-adhesive electrode pads are effective for defibrillation and cardioversion.

Arrhythmias, Cardiac↗
PubMed1985

Defibrillator electrode-chest wall coupling agents: influence on transthoracic impedance and shock success.

The purpose of this study was to determine if the difference in transthoracic impedance produced by different coupling agents affects the success of shocks for defibrillation. Three different coupling agents, Harco pads (Hewlett-Packard), Littman pads (3M) and Redux paste (Hewlett-Packard), were assessed in 10 anesthetized dogs in which ventricular fibrillation was induced by electrical stimulation of the right ventricle. Defibrillation was attempted 15 seconds later, using 50, 100 and 150 joules (selected energy). Actual delivered energy, current, impedance and the percent of the shocks that achieved defibrillation were determined for the three coupling agents. Redux paste gave significantly lower impedance and higher current than the two disposable performed coupling pads tested. Despite this, there were no significant differences in shock success among the three coupling agents. Thus, in this experimental model, over a three-fold energy range, disposable coupling pads were as effective as electrode paste for defibrillation despite the slightly higher impedance of the disposable pads.

Alcohols↗
PubMed1986

Double and triple sequential shocks reduce ventricular defibrillation threshold in dogs with and without myocardial infarction.

The role of optimal placement of electrodes and mode of shock delivery from a defibrillator was examined in dogs with and without myocardial infarction. Single, double and triple truncated exponential shocks separated by 1 ms were delivered through various electrode combinations and cardiac vectors after electrical induction of ventricular fibrillation. A single shock through a pathway not incorporating the interventricular septum (catheter electrodes or epicardial patches between anterior and posterior left ventricle) required the highest total energy (22.6 and greater than 26.4 J, respectively) and peak voltage (1,004 and greater than 1,094 V, respectively) to terminate ventricular fibrillation. A single shock through a pathway including the interventricular septum required lower total energy and peak voltage to defibrillate. Combinations of two sequential shocks between an intracardiac catheter electrode and anterior left ventricular epicardial patch, between the catheter electrode and subcutaneous extrathoracic plate and between three ventricular epicardial patches all significantly reduced total energy (7.7, 8.7 and 7.8 J, respectively) and peak voltage (424, 436 and 424 V, respectively) needed to defibrillate. Three sequential shocks exerted no significant additional reduction in total energy of the defibrillation threshold than did two sequential shocks. Infarcted canine heart required less peak voltage but not total energy to terminate ventricular fibrillation than did noninfarcted heart. Therefore, two sequential shocks over different pathways reduce both total energy and peak voltage required to terminate ventricular fibrillation.

Animals↗
PubMed1987

Automatic implantable cardioverter-defibrillator: patient survival, battery longevity and shock delivery analysis.

The automatic implantable cardioverter-defibrillator (AICD) has been shown to reduce the mortality rate of patients with malignant ventricular tachyarrhythmias. This report describes experience with implantation of 36 automatic implantable cardioverter-defibrillators (AID-B and AID-BR models) in 22 persons over a 44 month patient follow-up period (mean 19.6 months). There were five deaths: two patients died suddenly 22 and 29 months, respectively, after their second implant, one died of congestive heart failure, one died of respiratory failure and one died of catheter sepsis. Although 11 (50%) of the 22 patients never received a countershock for a ventricular tachyarrhythmia and are still alive, the other 11 received one or more spontaneous countershocks. Nine patients (41%) experienced spurious shocks during the follow-up period. Assuming that the first shock for presumed ventricular tachyarrhythmia prevented death, the hypothetical cumulative survival of patients at 42 months would have been 34 +/- 14.1% in the absence of an automatic implantable cardioverter defibrillator rather than the actual survival rate of 59 +/- 16.8%. The cumulative device survival of the 36 AID-B units was 92 +/- 5.62% at 15 months but diminished to 37 +/- 14.4% by 20 months. No unit lasted longer than 22 months. There were 12 battery depletions. The number of shocks emitted did not influence unit longevity. The manufacturer's elective replacement indicator is of uncertain validity. Six units remained active 7 to 17 months after surpassing their replacement indicator. The automatic implantable cardioverter-defibrillator prolongs the life of many patients with otherwise intractable arrhythmias.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1998

Effects of amiodarone and its active metabolite desethylamiodarone on the ventricular defibrillation threshold.

OBJECTIVES: We evaluated whether the reported difference in the ventricular defibrillation threshold (DFT) between short-term intravenous and oral amiodarone is due to the effect of amiodarone's active metabolite desethylamiodarone (DEA). BACKGROUND: Amiodarone is frequently used in patients with implantable cardioverter-defibrillator devices (ICD). Long-term oral amiodarone raises the DFT, but intravenous amiodarone has not been shown to have this effect. DEA, an active metabolite of amiodarone, has different electrophysiologic properties than its parent compound and may be responsible for the observed different effects of intravenous and oral amiodarone on DFT. METHODS: We ascertained the DFT in 24 pigs randomized to receive intravenous amiodarone, DEA or vehicle. Defibrillation was delivered through a transvenous lead system using a biphasic waveform. The DFT was determined using an up-down DFT algorithm and defined as the average minimal energies resulting in successful defibrillation delivered from ascending and descending serial shocks. RESULTS: Amiodarone caused a dose-response increase in DFT (mean +/- SD) from 22.7 +/- 4.1 (baseline) to 26.1 +/- 2.9 (10 mg/kg body weight), p = 0.11, to 34.9 +/- 8.2 J (after an additional 15 mg/kg), p = 0.035. DEA (10 mg/kg) caused an increase in DFT from 20.5 +/- 6.3 to 33.9 +/- 13.6 J, p < 0.01. Addition of 15 mg/kg of DEA resulted in hemodynamic instability and thus DFT was not obtained. In the control group, DFT decreased from 26.8 +/- 7.7 at baseline to 23.1 +/- 7.4 (dose 1), p = 0.19, to 22.8 +/- 6.2 J (dose 2), p = 0.18. CONCLUSIONS: DEA increases DFT by a greater amount than its parent drug amiodarone. There is an effect of intravenous amiodarone on DFT that is dose dependent.

Amiodarone↗
PubMed2000

Pharmacological atrial defibrillation via temporarily occluded coronary sinus: first clinical experience and implications for an implantable device.

UNLABELLED: The aim of this paper is to report the first experience of pharmacological atrial defibrillation in humans via a temporarily occluded coronary sinus. PATIENTS AND METHODS: In 6 patients (3 women, 3 men; mean age 57.8y, min 31, max 71), with clinical recurrences of atrial fibrillation, an occlusive coronary venogram was carried out in order to establish the origin of the Vein of Marshall. Atrial fibrillation was then induced by atrial pacing in all the patients and after an adequate waiting period to assure that the atrial fibrillation episode was persistent and stable, a bolus of a very low dose of an antiarrhythmic drug was delivered in 3-4 seconds into the temporarily balloon occluded coronary sinus near the orifice of the vein of Marshall. For both the venogram and the pharmacological test a Baim-Turi (USCI-Bard, Billerica MA) or a Vueport (Cardima, Fremont CA) catheter was used. RESULTS AND COMMENTS: In five patients a single dose of 7 mg of propafenone was immediately effective in restoring the sinus rhythm. In the remaining patient 2 doses of 7mg of propafenone failed to interrupt the arrhythmia, which was subsequently interrupted by a bolus of 0.1mg of ibutilide fumarate given after a waiting period of 20 minutes. Retroperfusion of the left atrium could account for these results; in fact the Vein of Marshall has no valvular apparatus in contrast with other coronary sinus tributary veins which are equipped with an uni- or bicuspidal valve. CONCLUSIONS: Pharmacological atrial defibrillation with a minimal dose of an antiarrhythmic drug delivered near the orifice of the Vein of Marshall via the temporarily occluded coronary sinus is feasible and effective. This new pharmacological atrial defibrillation can offer interesting opportunities in developing an implantable pharmacological atrial defibrillator.

Adult↗
PubMed1997

Metal cations defibrillize the amyloid beta-protein fibrils.

Amyloid beta-protein (A beta) is the major constituent of amyloid fibrils composing beta-amyloid plaques and cerebrovascular amyloid in Alzheimer's disease (AD). We studied the effect of metal cations on preformed fibrils of synthetic A beta by Thioflavin T (ThT) fluorescence spectroscopy and electronmicroscopy (EM) in negative staining. The amount of cross beta-pleated sheet structure of A beta 1-40 fibrils was found to decrease by metal cations in a concentration-dependent manner as measured by ThT fluorescence spectroscopy. The order of defibrillization of A beta 1-40 fibrils by metal cations was: Ca2+ and Zn2+ (IC50 = 100 microM) > Mg3+ (IC50 = 300 microM) > Al3+ (IC50 = 1.1 mM). EM analysis in negative staining showed that A beta 1-40 fibrils in the absence of cations were organized in a fine network with a little or no amorphous material. The addition of Ca2+, Mg2+, and Zn2+ to preformed A beta 1-40 fibrils defibrillized the fibrils or converted them into short rods or to amorphous material. Al3+ was less effective, and reduced the fibril network by about 80% of that in the absence of any metal cation. Studies with A beta 1-42 showed that this peptide forms more dense network of fibrils as compared to A beta 1-40. Both ThT fluorescence spectroscopy and EM showed that similar to A beta 1-40, A beta 1-42 fibrils are also defibrillized in the presence of millimolar concentrations of Ca2+. These studies suggest that metal cations can defibrillize the fibrils of synthetic A beta.

Alzheimer Disease↗
PubMed2003

The defibrillation efficacy of high frequency alternating current sinusoidal waveforms in guinea pigs.

There have been few basic studies of alternating current (AC) defibrillation, despite growing interest in the ability of AC to terminate or alter ongoing fibrillation. Based on fibrillation threshold testing, it has been suggested that cardiac tissue is most sensitive to long duration, low strength AC stimulation at around 50 Hz. This has not been directly tested for defibrillation. Two subcutaneous electrodes were placed 40 mm apart on opposing aspects of the guinea pig thorax. Seven seconds were allowed to elapse between fibrillation initiation and defibrillation. The tested waveforms were at 50, 100, 200, 500, and 1000 Hz with 2, 4, 8, 16, and 32-cycles. The efficacy of every waveform was measured using a single stimulus in a large population of animals. Forty-one guinea pigs were used in the fixed energy group. Thirty-three guinea pigs were used in the fixed amplitude group with additional 1-cycle waveforms tested. The 200-Hz and the 2-cycle waveforms were significantly more efficacious than those at other frequencies (P < 0.02) and other durations (P < 0.001). The 50-Hz waveforms were the least successful. Amplitude, not duration or energy, was the determinate of efficacy for 2-cycle (the most efficacious) waveforms. Unlike low strength stimulation, defibrillation strength stimuli are most effective with high frequency (200 Hz) pulses (2 cycles).

Animals↗
PubMed1998

The transthoracic impedance cardiogram is a potential haemodynamic sensor for an automated external defibrillator.

AIMS: The American Heart Association has endorsed the concept of Public Access Defibrillation. However, there have been reports of inappropriate direct current shocks from automatic external defibrillators. The specificity of automatic external defibrillators for shockable rhythms may be improved by the incorporation of a haemodynamic sensor. METHODS AND RESULTS: This study examined the use of four parameters extracted from the impedance cardiogram i.e. Peak dz/dt (the peak of the impedance cardiogram measured from the line dz/dt=0 ohms(-1)), Peak-trough (the peak-to-trough measurement of the impedance cardiogram ohms(-1)), Area 1 (the area under the C wave of the impedance cardiogram above the line dz/dt=0 mohm) and Area 2 (the area under the impedance cardiogram 50 ms on either side of the Peak and above the line dz/dt=0 mohm) as predictors of cardiac output. At 116 cardiac arrest calls the ECG and impedance cardiogram were recorded through two ECG/defibrillator pads placed in an antero-apical position. Nine recordings were rejected for artefact. The rhythm recorded in the remaining 107 calls was asystole (19), ventricular fibrillation (14), agonal rhythm (20), electromechanical dissociation (22), ventricular tachycardia (27) and sinus rhythm (5). These rhythms were divided into those associated with haemodynamic collapse i.e. no pulse -- asystole, ventricular fibrillation, agonal rhythm, electromechanical dissociation and shockable ventricular tachycardia (associated with loss of consciousness, pulselessness or a systolic blood pressure of <80 mmHg) (Group 1) and those associated with a satisfactory cardiac output i.e. non-shockable ventricular tachycardia (conscious with a pulse) and sinus rhythm (Group 2). On univariate analysis each of the four impedance cardiogram parameters were significantly greater in Group 2 than Group 1 (P<0.001). On multivariate analysis the parameters which best differentiated the two groups were Area 1 and Peak-trough. CONCLUSION: Thus the impedance cardiogram is a potential haemodynamic sensor for an automatic external defibrillator.

Adult↗
PubMed2002

Optimization of transthoracic ventricular defibrillation-biphasic and triphasic shocks, waveform rounding, and synchronized shock delivery.

The aim of this study is to optimize the truncated exponential waveform for transthoracic ventricular defibrillation. Discharge of a capacitor gives a fast-rising waveform with a spike; rounding of the waveform slows the rate of rise and removes the spike. Defibrillation thresholds for electrically induced VF were determined for rounded and conventional biphasic and triphasic waveforms (apex-anterior paddles; 130 microF capacitor; 3-10 ms phase duration), and for the Lown waveform in 29 anesthetized pigs. Rounding of the leading edge of the biphasic waveform reduced the threshold voltage and current for defibrillation at 3 + 3 ms and 6 + 6 ms phase duration, relative to the conventional unrounded biphasic or the Lown waveforms. The threshold delivered energy was lower for rounded truncated exponential biphasic shocks at 3 + 3 ms (55.3 +/- 2.5 J) than at 6 + 6 ms (67.6 +/- 2.9 J; reduction 15.9 +/- 3.8%; P <.001; n = 29) phase duration. Triphasic shocks (total duration 6-12 ms) showed no advantages over biphasic shocks in this model. The rounded waveform (6 + 6 ms phase duration) had a reduced delivered energy at threshold (9%) with transthoracic shock delivery synchronized to peak (71.1 +/- 4.2 J) or trough (71.5 +/- 4.9 J) of the high amplitude body surface electrocardiogram signal in ventricular fibrillation, compared with unsynchronized shocks (78.7 +/- 4.7 J; P <.05). In this study a biphasic, rounded waveform of total duration 6 or 12 ms, was optimal for the correction of electrically-induced ventricular fibrillation. Synchronization to the peak or trough of the high amplitude electrocardiogram signal gave a further reduction in the energy to defibrillate.

Animals↗
PubMed1980

Treatment of out-of-hospital cardiac arrests with rapid defibrillation by emergency medical technicians.

The survival rate for patients with out-of-hospital cardiac arrest is low in communities where emergency service is provided solely by emergency medical technicians. We trained such technicians in a suburban community of 79,000 to recognize and treat out-of-hospital ventricular fibrillation with up to three defibrillatory shocks without the use of medications or special airway protection. Outcomes from cardiac arrest due to underlying heart disease were determined during two periods: two years with standard care by emergency medical technicians and one year with defibrillator-trained technicians. During the period with standard care, four of 100 patients with cardiac arrest were resuscitated and discharged alive from the hospital, as compared with 10 of 54 patients during the period with defibrillator-trained technicians (P less than 0.01). In 12 of 38 patients with ventricular fibrillation, a stable perfusing cardiac rhythm followed defibrillatory shocks given by defibrillator technicians. The enhanced survival after cardiac arrest is encouraging, and further trials of defibrillation by emergency medical technicians are warranted.

Aged↗
PubMed1984

Prehospital defibrillation performed by emergency medical technicians in rural communities.

Survival after out-of-hospital cardiac arrest is poor in communities served only by basic ambulance services, but conventional advanced prehospital care is not an option for most rural communities. Ambulance technicians in 18 small communities (average population, 10,400) were trained to recognize and defibrillate ventricular fibrillation. Neither endotracheal intubation nor medication was used. Twelve additional communities of similar size where such early defibrillation was not attempted provided control data. In the communities where early defibrillation was available, 12 of 64 patients (19 per cent) who were found in ventricular fibrillation were resuscitated and discharged alive from the hospital; this was true of only 1 of 31 such patients (3 per cent) in the control communities, where only basic life support was available (P less than 0.05). Ten (83 per cent) of the long-term survivors received electrical shocks administered solely by the technicians. Early defibrillation by minimally trained ambulance technicians is an effective approach to emergency cardiac care in rural communities.

Adolescent↗
PubMed1998

The role of cardiac tissue structure in defibrillation.

The purpose of this paper is to investigate the relationship between cardiac tissue structure, applied electric field, and the transmembrane potential induced in the process of defibrillation. It outlines a general understanding of the structural mechanisms that contribute to the outcome of a defibrillation shock. Electric shocks defibrillate by changing the transmembrane potential throughout the myocardium. In this process first and foremost the shock current must access the bulk of myocardial mass. The exogenous current traverses the myocardium along convoluted intracellular and extracellular pathways channeled by the tissue structure. Since individual fibers follow curved pathways in the heart, and the fiber direction rotates across the ventricular wall, the applied current perpetually engages in redistribution between the intra- and extracellular domains. This redistribution results in changes in transmembrane potential (membrane polarization): regions of membrane hyper- and depolarization of extent larger than a single cell are induced in the myocardium by the defibrillation shock. Tissue inhomogeneities also contribute to local membrane polarization in the myocardium which is superimposed over the large-scale polarization associated with the fibrous organization of the myocardium. The paper presents simulation results that illustrate various mechanisms by which cardiac tissue structure assists the changes in transmembrane potential throughout the myocardium. (c) 1998 American Institute of Physics.

Journal Article↗
PubMedDate not supplied

Assessment of balanced biphasic defibrillation waveforms in transthoracic atrial cardioversion.

Various electrical pulses have been used for defibrillation. The monophasic damped sinusoid waveform, initiated in 60 s, was adopted in virtually all defibrillators. Biphasic pulses were introduced recently, achieving success with less energy. A biphasic exponential waveform was modelled with 4 ms duration per phase with a balanced 3:1 ratio of the first to second phase peak voltages and implemented in a defibrillator. A version obtained by chopping the pulses with a 5 kHz frequency was also used. It was hypothesized that the modelled transmembrane voltage decay time is a parameter that could be associated with successful defibrillation. The results of cardioversion for two groups of patients with the 'classic' monophasic waveform and with the biphasic pulses were compared. The mean efficient energy with the damped sinusoid was 205 +/- 85 J, versus 88 +/- 43 J with the biphasic pulses, yielding a ratio of 2.32 (1.92 to 3.2 for fibrillation and flutter, respectively). An acceptable agreement between model data and clinical results was found. The transmembrane voltage decay time ratios for monophasic versus biphasic pulses was in the approximate range of 2.5 to 3.5.

Atrial Fibrillation↗
PubMedDate not supplied

Transthoracic defibrillation with chopping-modulated biphasic waveforms.

The superiority of different biphasic pulses for transthoracic defibrillation was proven by several studies. These efficient waveforms were implemented in some commercially available defibrillators. Recently we have devised and evaluated a biphasic waveform with a specially balanced ratio of the first-to-second phase voltages and with 5 kHz frequency 1:1 on-off chopping. It used less than half the energy for successful defibrillation in comparison with the 'classic' monophasic damped sinusoidal wave and showed considerably less post-shock negative effects. This experience led us to try several laws of chopping modulation. A pulse-width modulation, combining low energy with gradual upslope of the modelled transmembrane potential, proved to have better performance than the standard damped sinusoid wave and the non-chopped biphasic truncated exponential pulse. This waveform was tested in a series of animal experiments in comparison with other modulated pulses, with the non-modulated waveform and the standard damped sinusoid wave. The experiments demonstrated the superiority of the modulated waveform, assessed by combining the parameters of threshold defibrillation energy and of post-shock disturbances reduction.

Animals↗
PubMedDate not supplied

Cost-effectiveness analysis of a rural/urban first-responder defibrillation program.

OBJECTIVE: To analyze the cost-effectiveness of a proposed first-responder defibrillation program in a small rural area in comparison with a recently initiated first-responder program in an adjoining urban center in southwestern Ontario. The purpose of the analysis was to quantify the expected benefits of the proposed program to determine whether the costs are justified. METHODS: This analysis was conducted on the city of Waterloo (population 80,000 over 25 square miles) and the adjoining rural township of Wellesley (population 8,000 over 105 square miles). The township has volunteer fire department first responders with basic life support (BLS), and basic life support/defibrillation (BLS-D) ambulances as the second tier; whereas the city's full-time fire department has recently adopted a first-responder defibrillation (BLS-D) program backed up by the same BLS-D ambulance service. The most relevant costs identified were the capital costs of the defibrillators, ancillary equipment, and biomedical service for preventive maintenance and routine nonwarranty work. Response intervals and percentage of patients found in ventricular fibrillation were projected and sensitivity analysis was applied. RESULTS: The projected cost per life saved is $6,776 (C) in the urban area and $49,274 (C) in the rural area using an incremental save rate of 6%. Applying sensitivity analysis to the data, the save rate varied from 2% to 10%, resulting in a cost per life saved of $20,328 (C) and $4,066 (C), respectively, in the urban community. For the rural area, the cost per life saved ranged from $147,821 (C) (2%) to $29,564 (C) (10%). Even the worst-case save rate for the urban center [2%; $20,328 (C)] is significantly less than the best-case save rate [10%; $29,564 (C)] for the rural area. CONCLUSIONS: The cost per life saved for a rural first-responder defibrillation program is significantly more expensive than one for an urban center. However, the cost per life saved is still economical compared with common treatments for other life-threatening illnesses.

Cost-Benefit Analysis↗
PubMedDate not supplied

Time to first shock by emergency medical technicians with automated external defibrillators.

UNLABELLED: The interval from collapse to electrical rescue shock is a critical determinant of successful defibrillation in cardiac arrest. In order to achieve the earliest possible defibrillation, many emergency medical services (EMS) systems equip first-responding units with an automated external defibrillator (AED). OBJECTIVE: To measure the time from on-scene emergency medical technician (EMT) recognition of cardiac arrest to AED application and shock in ventricular fibrillation (VF) arrest. In addition, the authors sought to understand the reasons for delays. METHODS: Using the AED recordings and written EMS reports, the authors conducted a retrospective cohort study of all persons who experienced an EMS-attended VF cardiac arrest in which an AED was applied and a shock delivered by an EMT, from January 1999 through December 2000 (n = 177). Based on the bimodal distribution of times, two groups were assembled: no delay (time to shock < or = 90 seconds) and delayed (time to shock > 90 seconds). Patient and event characteristics associated with delay status were determined using Mantel-Haenszel methods. RESULTS: The median (25th, 75th percentile) time from cardiac arrest recognition to shock was 51 (43, 64) seconds. Ninety-four percent (n = 166) of the cohort received a shock within 90 seconds. Delayed shock was associated with unwitnessed arrest status (odds ratio = 9.3, 95% confidence interval = 2.3, 36.8) and nursing home location (odds ratio = 10.0, 95% confidence interval = 2.1, 47.5). CONCLUSION: The findings suggest that a 1-minute goal and a 90-second minimum standard for time to first shock are appropriate for EMT AED defibrillation in the field.

Aged↗
PubMedDate not supplied

Automated external defibrillation by very young, untrained children.

UNLABELLED: For patients with sudden cardiac death (SCD), the time interval to defibrillation is the main determinant of survival. As such, the American Heart Association has attempted to promote public-access defibrillation (PAD). Previous studies have shown that automated external defibrillators (AEDs) can be used successfully by untrained adults. OBJECTIVE: To determine whether very young, untrained children could use AEDs. METHODS: Third-grade students from an elementary school participated in this study representing a convenience sample of volunteers. They were given no formal training, but were shown how to peel off the backing from the electrode pads, like a sticker. Students were then given a mock code situation using a training manikin. The time to delivery of first shock was recorded. Students were then trained during a 2-minute review of the process, one on one with an instructor, and the study was then repeated. Data were analyzed using a paired Student's t-test comparing pre- and post-training. RESULTS: Thirty-one children participated in the study, with a median age of 9 years. For untrained children, the mean time for delivery of the first shock was 59.3 +/- 13.6 seconds, 95% CI = 54.3 to 64.3. Following training, the mean time for delivery of the first shock was 35.2 +/- 6.0 seconds, 95% CI = 33.0 to 37.4, p = 0.001. CONCLUSION: Although this study suggests that even very young, untrained children can successfully perform automated external defibrillation, training does significantly decrease the time to delivery of first shock.

Automation↗