A Review of External Defibrillation Strategies.

The past, present, and future of the implantable cardioverter defibrillator

Part 6: Advanced Cardiovascular Life Support

External Defibrillation: The Need for Uniformity in Analyzing and Reporting Results

The recommendations for electrical therapies described in this section are designed to improve survival from SCA and life-threatening arrhythmias. Whenever defibrillation is attempted, rescuers must coordinate high-quality CPR with defibrillation to minimize interruptions in chest compressions and to ensure immediate resumption of chest compressions after shock delivery. The high first-shock efficacy of newer biphasic defibrillators led to the recommendation of single shocks plus immediate CPR instead of 3-shock sequences that were recommended prior to 2005 to treat VF. Further data are needed to refine recommendations for energy levels for defibrillation and cardioversion using biphasic waveforms.

Dear Editor; External defibrillation in patients with implanted neuromodulatory devices is a crucial therapeutic challenge. We report a 63-year-old male patient with refractory epilepsy (RE) after recurrent ischaemic strokes in the middle cerebral artery and in the anterior cerebral artery territory 26 and 23 years ago. He received various therapeutic interventions to achieve seizure control with insufficient success. Therefore, vagus nerve stimulation (VNS) (model Pulse 102, Aspire SR, Cyberonics Inc, Houston, Texas) was applied via insertion of a pulse generator in the left upper chest in 2011. VNS stimulation settings were: output current 1.0 mA, pulse width 500 µs, frequency 30 Hz, 30s ON, 3.0 minute OFF. A reduction of seizure frequency was achieved. Last antiepileptic therapy consisted of levetiracetam 1500 mg td, valproate 1000 mg td, and eslicarbazepine 800 mg td. In 2016, he was admitted because of generalized seizure and aspiration pneumonia. During hospital stay he suffered a cardiac arrest (CA) with pulseless ventricular tachycardia (VT) caused by fulminant pulmonary artery embolism. After successful resuscitation, the patient experienced return of spontaneous circulation (ROSC). During resuscitation, biphasic electric shocks were applied using 150 Joule and subsequently 360 Joule with patches placed approximately 10 cm parasternal and at the left chest below the VNS. After successful ROSC the VNS was checked again and no malfunction could be detected. Stimulation settings were not changed. Impedance was normal. Seizures were not observed during the remaining day. Unfortunately, the patient died within one day after successful resuscitation and ROSC because of therapy refractory circulatory insufficiency. VNS is an established therapeutic approach in treatment of TRE in children and adults to achieve reduction of seizure frequency with proven safety and efficacy. The safety of VNS in emergency situations like cardiac arrest due to VF with need of external defibrillation and application of large amounts of electrical energy is not clear. External defibrillation in VNS patients may potentially be harmful. The literature concerning external defibrillation during resuscitation or external cardioversion (EC) in patients with implanted electronic devices in neurological disorders is sparse. In patients with cardiac pacemakers external defibrillation may damage the cardiac device. EC applied to deep brain stimulation (DBS) patients may cause thalamotomy or DBS failure. Application of electroconvulsive therapy in psychiatric disorders seems to be safe. Two cases of electroconvulsive therapy (ECT) in VNS have been reported by Sharma et al. The first patient was a 66-year old female with major depression and the second one, a 57-year-old male with a history of bipolar disorder. Both had VNS for therapy refractory psychiatric illness. ECT was applied because of further worsening of the mental state without malfunction of the VNS device. To our knowledge, this is the first case of external defibrillation in a patient with VNS for TRE without alteration of the neurostimulator’s function. External defibrillation applied to VNS patients seem to be safe and effective. Several steps should be taken to minimize the electrical current flowing through the neurostimulator. First, position the patches as far away as possible from the VNS at least 10 cm each. Second, position the patches perpendicular to the VNS; use the lowest clinically appropriate output setting, and, finally, confirm that the VNS is functioning properly after defibrillation.

A 20-year-old asymptomatic man was diagnosed with hypertrophic cardiomyopathy (HCM) after routine physical examination during which a systolic heart murmur was detected.Echocardiography showed massive left ventricular (LV) hypertrophy with ventricular septal thickness of 36 mm extending into the anterolateral wall (30 mm); outflow obstruction was absent.Ambulatory (Holter) ECG showed 3 isolated premature ventricular contractions, and blood pressure response to exercise was normal.Echocardiographic examinations in parents and siblings were negative for HCM.Although 2 centers advised against an implantable cardioverter-defibrillator (ICD) based on the presence of only 1 risk factor for sudden death (ie, extreme hypertrophy), a prophylactic device was recommended by a third cardiac consultant.After an uneventful 16-month period during which the ICD neither detected nor treated arrhythmias, an unprovoked episode of ventricular fibrillation triggered a defibrillation shock that immediately restored sinus rhythm (Figure 1).

In October 1993 the American Heart Association appointed the Task Force on Automatic External Defibrillation. The task force was charged with conducting a conference on automatic external defibrillation, evaluating research needed for broader community use of automatic external defibrillators, and overseeing evaluation of the feasibility and desirability of their use by healthcare professionals and the lay public. In December 1994 a conference on public access defibrillation was held in Washington, DC. More than 300 persons attended, representing science, industry, the healthcare professions, law, and the federal government. During the meeting the participants reached a consensus on the general proposition of greater public access to defibrillation and the need for broad-based clinical …

Detached from the 'Gentleman's Magazine', October-November, 1801. In volume lettered: Miscellaneous on China.

Defibrillators

The objective of the present work is to conduct a Health Technology Assessment (HTA) on the use of the Wearable Cardioverter Defibrillator (WCD) in patients at risk of Sudden Cardiac Arrest (SCA) following Myocardial Infarction (MI) or with an explanted Implantable Cardioverter Defibrillator (ICD).

A wearable automated external defibrillator has been shown to be efficacious in the prevention of sudden death in adults who had a history of cardiac arrest but who did not have a permanent internal cardioverter/defibrillator (ICD) placed. The use of a wearable defibrillator has not been established in the pediatric population. We retrospectively reviewed the clinical database for the wearable external defibrillator from ZOLL Lifecor Corporation (Pittsburgh, PA, USA). We compared the use of the wearable defibrillator in patients ≤18 years of age to those aged 19-21 years. There were 81 patients ≤18 years of age (median age = 16.5 years [9-18] and 52% male). There were 103 patients aged 19-21 years (median age = 20 years [19-21] and 47% male). There was no difference between groups in average hours/day or in total number of days the patients wore the defibrillator. In patients ≤18 years of age, there was one inappropriate therapy and one withholding of therapy due to a device-device interaction. In patients aged 19-21 years, there were five appropriate discharges in two patients and one inappropriate discharge in a single patient. It is reasonable to consider the wearable automated external defibrillator as a therapy for pediatric patients who are at high risk of sudden cardiac arrest but who have contraindications to or would like to defer placement of a permanent ICD. As there were no appropriate shocks in our patients ≤18 years of age, this study cannot address efficacy of the therapy.

In reply

On the basis of the published evidence to date, the Pediatric Advanced Life Support (PALS) Task Force of ILCOR has made the following recommendation (October 2002): This statement expands and clarifies the 2000 ILCOR recommendations about the potential use of AEDs in children. The need for this update has become critical. A growing number of AEDs for adults are being placed in public access settings, and the use of AEDs by nontraditional responders is increasing. The likelihood for use of AEDs in smaller (<25 kg), younger (<8 years of age) patients is now a reality. This statement provides the rationale for development of AEDs, outlines questions about the efficacy and safety of AEDs used in smaller, younger children, and summarizes recent efforts to justify the use of existing or modified AEDs in smaller, younger children. ### Rationale for AED Use The primary determinant of survival from VF cardiac arrest is the time interval from collapse until defibrillation. Out-of-hospital defibrillation within the first 3 minutes of witnessed adult … Address correspondence to Ricardo A. Samson, MD, Department of Pediatrics, 1501 N Campbell, Tucson, AZ 85724-5073. E-mail: rsamson{at}peds.arizona.edu

Part 6: Defibrillation

Introduction:In industrialized countries, sudden cardiac death is a serious public health problem that accounts for about 15% to 20% of all deaths, with an incidence of 0.5 to 3 deaths per 100,000 athletes. In recent years, although both first aid prevention programs and the availability of External Automatic Defibrillator (AED) in public places have increased, few data are available with respect to real knowledge about the use of such devices. The aim of this study is to detect the level of knowledge and skills in the use of automatic external defibrillators among sports and management staff in sports facilities.Materials and Methods:A cross-sectional, multicentre study conducted in 16 sports facilities in the Province of Lecce, Italy, and targeted to all the athletic and managerial staff of these sports facilities. Information was obtained through a validated questionnaire consisting of 27 items.Results:339 participants of which 59.3% male (n=201) (average=33.6; SD=13.1). 51.6% (n=175) were informed about the presence of the defibrillator, only 38.1% (n=129) declared to know where it was placed and 43.7% (n=96) considered it to be quite or very accessible. The majority of them (78.8%; n=267) were never involved in a training course and declared limited knowledge about the use of this device.Conclusions:Respondents stated that they have poor knowledge and skills in the use of the defibrillator, its operation and maintenance, which could reduce the positive outcomes of early treatment. Further studies should be conducted, although it may be appropriate to implement specific training courses for personnel working in sports centres. (www.actabiomedica.it)