Development and application of "Special defibrillator for teaching and training".

BACKGROUND: To provide an economical and practical defibrillator for first aid teaching and training, to reduce the cost of teaching and training, increase teaching and training equipment, provide trainees with more hands-on training sessions, and improve first aid capabilities. METHODS: Developing a special teaching defibrillator with the same structure and operation configuration as the clinical medical emergency defibrillator. The appearance, structure and operating accessories of the two defibrillators are the same. The difference between the defibrillator and the clinical medical emergency defibrillator are as follows: the clinical medical emergency defibrillator can be energized, and there are expensive electronic accessories and defibrillation accessories for charging and discharging in the machine. When discharging, the electrode plate has current discharged into the human body; the power plug of the "special defibrillator for teaching and training" is a fake plug. When the power is plugged in, no current enters the body and the machine. There are no expensive electronic accessories and defibrillation accessories for charging and discharging, and no current is discharged during discharge. Then compare the teaching effect of the special defibrillator for teaching and training and the clinical medical emergency defibrillator (including operation score and attitude after training). RESULTS: The scores of defibrillator operation in the experimental group of junior college students (87.77 ± 4.11 vs. 83.30 ± 4.56, P < 0.001) and the experimental group of undergraduate students (90.40 ± 3.67 vs. 89.12 ± 3.68, P = 0.011) were higher than those in the corresponding control group; The attitude of junior college students in the experimental group and undergraduate students in the experimental group after training was more positive than that of the corresponding control group (P < 0.05). CONCLUSIONS: The special defibrillator for teaching and training can save the purchase cost of teaching equipment, increase teaching and training resources, and improve the trainee's defibrillation ability, defibrillation confidence and defibrillation security.

Canadian Heart Rhythm Society Task Force Report on Physician Training and Maintenance of Competency for Cardiovascular Implantable Electronic Device Therapies: Executive Summary.

Physicians engaged in cardiovascular implantable electronic device (CIED)-related practice come from diverse training backgrounds with variable degrees of CIED implant training. The objective of the Canadian Heart Rhythm Society Task Force on CIED Implant Training was to establish a common structure and content for training programs in CIED implantation, related activities and maintenance of competency. This executive summary presents the essence of the report with key recommendations included, with the complete version made available in a linked supplement. The goals are to ensure that future generations of CIED implanters are better prepared for continuously evolving CIED practice and quality care for all Canadians.

Double external defibrillation for shock-refractory ventricular fibrillation cardiac arrest: A step towards standardization.

Double (or dual) external defibrillation (DED) has increasingly been used in the last few years by a number of emergency medical services (EMS) as a last resort to terminate ventricular fibrillation and pulseless ventricular tachycardia in adult patients who remain refractory to standard defibrillation. However, no randomized controlled trials comparing DED with standard defibrillation focusing on patient-oriented outcomes as the primary objective have been published to date. Selection criteria, procedure techniques, and protocol are not clearly defined and vary across observational studies. The terms and/or nomenclature used to describe DED are confusing and vary throughout the literature. Despite increased use of DED, many questions remain as to which patients will derive the most benefit from DED, when to implement DED, and the optimal form of delivering DED. The present paper provides a brief overview of the background, procedure techniques, pad placement, and factors affecting how DED is delivered. A further objective of this paper is to offer a proposal for a uniform nomenclature and a standardized protocol in the form of a flowchart for EMS agencies to guide further clinical trials and best practices. This paper should not only help give background on novel definitions and clarify nomenclature for this practice, but more importantly should help institutions lay the groundwork for performing EMS-based large trials to further investigate the effectiveness of DED.

The safety and efficacy of hands-on defibrillation in the management of adult cardiac arrest: A systematic review.

OBJECTIVE: Hands-on defibrillation (HOD) is a technique that has great potential to positively impact outcomes from cardiopulmonary resuscitation (CPR) with the removal of an interruption in chest compressions. The safety and efficacy of HOD, however, have yet to be proven. This review aims to examine the safety of HOD, and secondarily, its efficacy. METHODS: A systematic literature search was performed through PubMed, MEDLINE, Google Scholar, and the Cochrane Database. Additional articles were selected from the reference lists of this search result. RESULTS: From 52 results, 26 articles were reviewed and from the references of these articles, 9 more were included, leaving 35 articles for analysis. 14 of the analyzed articles were excluded. CONCLUSIONS: HOD generally appears safe, though significant uncertainty still remains for each protective barrier type. HOD appears to be efficacious in improving CPR with no strong evidence to suggest otherwise.

Hemodynamic response of restoring sinus rhythm in critically ill patients with atrial fibrillation.

BACKGROUND: Electrical cardioversion (ECV) is the recommended treatment for atrial fibrillation (AFib) in critically ill patients, despite lacking data showing hemodynamic benefits of restoring sinus rhythm in this setting. The aim of this study was to assess the hemodynamic effect of successful ECV in a cohort of hemodynamically unstable critically ill patients. METHODS AND RESULTS: This study included 66 successful ECV performed in hemodynamically unstable critically ill patients with new-onset AFib. The primary outcome was the requirement of norepinephrine and inotropes 6 h after successful ECV in relation to baseline. Baseline norepinephrine dose was 0.19 ± 0.02 µg/kg/min, and 67% of patients were treated with positive inotropic drugs. Six hours after ECV, 33 patients (50%) were considered hemodynamic non-responders. Overall, the mean norepinephrine dose at 6 h was 0.17 ± 0.02 µg/kg/min (P = 0.051 compared to baseline) and 61% of patients were on inotropes (P = 0.13 compared to baseline). During the 6-hour period after ECV the mean norepinephrine dose temporary increased to 0.20 ± 0.02 µg/kg/min (P = 0.033 compared to baseline). CONCLUSIONS: ECV is associated with a large proportion of hemodynamic non-responders and a numerically modest, non-significant hemodynamic improvement in critically ill patients with new-onset AFib.

Double sequential defibrillation for out-of-hospital refractory ventricular fibrillation: A scoping review.

BACKGROUND: Double sequential defibrillation (DSD) has been proposed as a viable treatment option for patients in refractory ventricular fibrillation/pulseless ventricular tachycardia (VF/pVT) out-of-hospital cardiac arrests (OHCA). However, currently there is insufficient evidence to support a widespread implementation of this therapy. STUDY OBJECTIVES: The aim of this scoping review was to summarize the current available evidence of DSD for patients with refractory VF/pVT OHCA as well as to identify gaps in the literature that may require further research. METHODS: We conducted a comprehensive literature search of MEDLINE via PubMed, Embase via Ovid, and Scopus on August 19, 2019. We also checked reference lists of relevant papers to identify additional studies. Any controlled clinical study design (randomized controlled trials and non-randomized controlled trials), and observational studies (cohort studies and case-control studies) providing information on resuscitative parameters, survival rates and neurological outcomes in adults (≥ 18 years old) treated with DSD for refractory VF/pVT OHCA were included. Two investigators independently conducted the literature search, study selection, and data extraction. RESULTS: The search yielded 1612 unique records, of which 4 peer-reviewed articles were found relating to the research purpose, totaling 1061 patients of who 20.5% (n = 217) received DSD. Most studies evaluated if pre-hospital DSD was associated with improved survival to discharge after refractory VF/pVT. No randomized controlled trials were identified. CONCLUSION: To date, it is difficult to conclude the real benefit of DSD for patients in refractory VF based on the available evidence. The findings of this scoping review suggest there is limited evidence to support at large-scale the use of DSD for refractory VF/pVT OHCA. Further research is needed to better characterize and understand the use of DSD for refractory VF/pVT, in order to implement best practices to maximize the effectiveness and efficiency of care.

Additional antitachycardia pacing programming strategies further reduce unnecessary implantable cardioverter-defibrillator shocks.

BACKGROUND: Antitachycardia pacing (ATP) is routinely used to terminate ventricular tachyarrhythmias (VTs). However, little guidance exists on the most effective programming of ATP. OBJECTIVE: This study evaluated whether additional ATP sequences are more effective in reducing implantable cardioverter-defibrillator shocks. METHODS: In patients from the Shock-Less study, the number of overall shocks were compared between patients programmed to ≤3 ATP sequences (VT zone) and ≤1 ATP sequence (fast ventricular tachycardia [FVT] zone) (nominal group) and patients programmed to receive additional ATP sequences in VT (>3) or FVT (>1) zones. RESULTS: Of the 4112 patients (15% receiving secondary prevention; 77% men; mean age 65.9 ± 12.6 years), 1532 patients (37%) were programmed with additional ATP sequences (1025 with >3 ATP sequences in the VT zone; 699 patients with >1 ATP sequence in the FVT zone). Over a mean follow-up period of 19.6 ± 10.7 months, 4359 VT/FVT episodes occurred in 591 patients. Compared with the nominal group, in patients with additional ATP programming, there was a 39% reduction in the number of shocked VT episodes (0.46 episodes per patient-year vs 0.28 episodes per patient-year; incidence rate ratio [IRR] 0.61; P < .001) and a 44% reduction in the number of shocked FVT episodes (0.83 episodes per patient-year vs 0.47 episodes per patient-year; IRR 0.56; P < .001). The reduction in shocked VT episodes was observed in both primary (IRR 0.68; 95% confidence interval 0.51-0.90; P = .007) and secondary (IRR 0.51; 95% confidence interval 0.35-0.72; P < .001) prevention patients. CONCLUSION: Programming more than the nominal number of ATP sequences in both the VT and FVT zones is associated with a lower occurrence of implantable cardioverter-defibrillator shocks in clinical practice.

Is delayed cardioversion the better approach in recent-onset atrial fibrillation? Yes.

Atrial fibrillation is the most common sustained arrhythmia encountered in primary care practice and represents a significant burden on the health care system with a higher than expected hospitalization rate from the emergency department. The first goal of therapy is to assess the patient's symptoms and hemodynamic status. There are multiple acute management strategies for atrial fibrillation including heart rate control, immediate direct-current cardioversion, or pharmacologic cardioversion. Given the variety of approaches to acute atrial fibrillation, it is often difficult to consistently provide cost-effectiveness care. The likelihood of spontaneous conversion of acute atrial fibrillation to sinus rhythm is reported to be really high. Although active cardioversion of recent-onset atrial fibrillation is generally considered to be safe, the question arises of whether the strategy of immediate treatment for a condition that is likely to resolve spontaneously is acceptable for hemodynamically stable patients. Based on published data, non-managed acute treatment of atrial fibrillation appears to be cost-saving. The observation of a patient with recent-onset atrial fibrillation in a dedicated unit within the emergency department reduces the need for acute cardioversion in almost two-thirds of the patients, and reduces the median length of stay, without negatively affecting long-term outcome, thus reducing the related health care costs. However, to let these results broadly applicable, defined treatment algorithms and access to prompt follow-up are needed, which may not be practical in all settings.

Is delayed cardioversion the better approach in recent-onset atrial fibrillation? No.

Symptomatic atrial fibrillation (AF) is a common cause of emergency department (ED) referrals. In case of hemodynamic stability, the choice to either perform early cardioversion (pharmacologic or electrical) or to prescribe rate-lowering drugs and differ any attempts to restore sinus rhythm (i.e., wait-and-see approach) has been widely debated. Results of the recent Rate Control versus Electrical Cardioversion Trial 7-Acute Cardioversion versus Wait and See (RACE 7 ACWAS) have been considered a strong argument in favor of the wait-and-see approach. In this debate, we discuss several issues that would support early cardioversion, ranging from patients' satisfaction and costs to concerns about safety. Furthermore, the wait-and-see approach may translate into a missed opportunity to encourage widespread use of a "pill-in-the-pocket" home treatment: this underused option could allow rapid solving of many AF episodes, potentially avoiding future ED referrals. Our opinion is that a delayed cardioversion may introduce unneeded complications in the straightforward management of a common clinical problem. Therefore, early cardioversion should continue to be the preferred option because of its proven efficacy, safety and convenience.

Improving Communication in Heart Failure Patient Care.

BACKGROUND: Although implantable cardioverter-defibrillators (ICDs) reduce sudden death, these patients die of heart failure (HF) or other diseases. To prevent shocks at the end of life, clinicians should discuss deactivating the defibrillation function. OBJECTIVES: The purpose of this study was to determine if a clinician-centered teaching intervention and automatic reminders increased ICD deactivation discussions and increased device deactivation. METHODS: In this 6-center, single-blinded, cluster-randomized, controlled trial, primary outcomes were proportion of patients: 1) having ICD deactivation discussions; and 2) having the shocking function deactivated. Secondary outcomes included goals of care conversations and advance directive completion. RESULTS: A total of 525 subjects were included with advanced HF who had an ICD: 301 intervention and 224 control. At baseline, 52% (n = 272) were not candidates for advanced therapies (i.e., cardiac transplant or mechanical circulatory support). There were no differences in discussions (41 [14%] vs. 26 [12%]) or deactivation (33 [11%] vs. 26 [12%]). In pre-specified subgroup analyses of patients who were not candidates for advanced therapies, the intervention increased deactivation discussions (32 [25%] vs. 16 [11%]; odds ratio: 2.90; p = 0.003). Overall, 99 patients died; there were no differences in conversations or deactivations among decedents. SECONDARY OUTCOMES: Among all participants, there was an increase in goals of care conversations (47% intervention vs. 38% control; odds ratio: 1.53; p = 0.04). There were no differences in completion of advance directives. CONCLUSIONS: The intervention increased conversations about ICD deactivation and goals of care. HF clinicians were able to apply new communication techniques based on patients' severity of illness. (An Intervention to Improve Implantable Cardioverter-Defibrillator Deactivation Conversations [WISDOM]; NCT01459744).

Ascending Defibrillation Waveform Significantly Reduces Myocardial Morphological Damage and Injury Current.

OBJECTIVES: This study tested the hypothesis that a biphasic defibrillation waveform with an ascending first phase (ASC) causes less myocardial damage by pathology and injury current than a standard biphasic truncated exponential (BTE) waveform in a swine model. BACKGROUND: Although lifesaving, defibrillation shocks have significant iatrogenic effects that reduce their benefit for patient survival. METHODS: An ASC waveform with an 8-ms linear ramp followed by an additional positive 0.5-ms decaying portion with amplitudes of 20 J (ASC 20J) and 25 J (ASC 25J) was used. The control was a 25-J BTE conventional waveform (BTE 25J) RESULTS: The ASC 20J and ASC 25J shocks were both successful in 6 of 6 pigs, but the BTE 25J was successful in only 6 of 14 pigs (p < 0.05). Post-shock ST-segment elevation (injury current) in the right ventricular electrode was significantly greater with BTE 25J than with ASC 20J and ASC 25J. With a blinded pathology reading, hemorrhage, inflammation, thrombi, and necrosis 24 h post-shock were significantly greater with BTE 25J than with ASC 20J and ASC 25J. Troponin levels were also markedly lower at 3, 4, 5, and 6 h post-shock. CONCLUSIONS: Defibrillation shocks cause electrophysiological, histological, and biochemical signs of myocardial damage and necrosis. These signs of damage are markedly less for an ASC waveform than for a conventional BTE waveform.

The Wearable Cardioverter Defibrillator: A Case Study Illustrating Physical Therapy Implications and Management in the Inpatient Setting.

Background and Purpose: Sudden cardiac death causes an estimated 200,000 to 450,000 deaths per year in the USA. Although permanent implantation of an internal cardiac defibrillator offers a preventive intervention, the required assessment period for determining need creates vulnerability for patients who will benefit from this protection. The use of a wearable cardioverter defibrillator (WCD) for interim protection is rapidly increasing. There are no rehabilitation guidelines for patients wearing a WCD. This article reviews the WCD's purpose, considers implications and current challenges for use during rehabilitation, and illustrates this with a case report. Case Description: A 51-year-old male with coronary artery disease following prolonged hospitalization was fitted with a WCD during evaluation for an internal cardiac defibrillator. During inpatient rehabilitation, the therapy plan required unique considerations because of the presence of the WCD. Outcomes: Recapitulating the patient's rehabilitation course illustrates the WCD's challenges, the benefits to exercise progression, and the safety measures used. The patient gained functional independence, with uninterrupted care, in the presence of the WCD. Discussion: Knowledgeable clinicians, attention to safety, and sufficient patient/caregiver education are essential for uninterrupted and successful rehabilitative care for WCD-wearing patients. Because of increasing clinical prevalence of WCDs in rehabilitation, it is critically important to share clinical experience and eventually conduct a systematic assessment.

Long-term use of the wearable cardioverter defibrillator in patients with explanted ICD.

OBJECTIVES: To evaluate the effectiveness of wearable cardioverter defibrillator (WCD) use in protecting patients from sudden cardiac arrest (SCA) while they were treated in nonhospital settings until re-implantation of an Implantable cardioverter-defibrillator (ICD) was feasible. We sought to determine whether the WCD could be successfully utilized long term (≥1 year) after ICD extraction in patients at continued risk of SCD in which ICD re-implantation was not practical. BACKGROUND: ICDs have proven to improve mortality in patients for both secondary and primary prevention of SCA. Increased ICD implantation in older patients with comorbid conditions has resulted in higher rates of cardiac device infections. Currently, a wearable cardioverter defibrillator (WCD) is an alternative management for SCA prevention in specific cases. METHODS: This a retrospective analysis based on consecutive WCD patients who underwent ICD explant due to device-related infections or mechanical reasons between April 2007 and July 2014. A total of 102 patients were identified from the national database maintained by ZOLL (Pittsburgh, PA, USA). We analyzed the reason for WCD use, demographic information, device data, compliance and duration of WCD use, detected arrhythmias and therapies, and reason for discontinuing WCD use. RESULTS: In these long term WCD users, average length of WCD use was 638 ±â€¯361 days. Nine patients (8.8%) had a sustained ventricular arrhythmia that was successfully resuscitated by the WCD. Six patients (5.8%) experienced inappropriate shocks. Two patients (1.9%) died of asystole events while wearing the WCD and an additional 10 patients died while not monitored by the WCD. Thirty-nine patients (38.2%) ended WCD use when a new ICD was implanted and 15 patients (14.7%) were still wearing the WCD at the time of analysis. CONCLUSIONS: We found that extending use of the WCD to ≥1 year is a safe and effective alternative treatment for patients with explanted ICDs who are not pacemaker dependent.

Value of Regular Defibrillation Threshold Testing After Extracardiac Implantable Cardioverter Defibrillator Placement in Small Children During Mid-Term Follow-Up.

OBJECTIVES: The purpose of this study was to analyze course of defibrillation threshold (DFT) with growth. BACKGROUND: Data on regular DFT testing after extracardiac implantable cardioverter-defibrillator (ICD) placement in infants and small children is still limited. METHODS: An extracardiac ICD was placed in 23 pediatric patients (median age 6.1 years; median body weight 21 kg, median length 120 cm). The defibrillator lead was tunneled pleurally, and the device was placed as "active can" in the right upper abdomen or in a horizontal position between the diaphragm and the pericardium, respectively. DFT was verified intraoperatively, 3 months later, and every 12 months thereafter. The aim was to achieve DFT <15 J allowing ICD programming with a double safety margin above DFT. RESULTS: In all 23 patients, an intraoperative DFT <15 J could be accomplished. Serial DFT testing showed an increase from a median DFT of 10 J intraoperatively to 15 J after 1 year. During mean follow-up of 2.0 years, a significant correlation between DFT and body length, but not body weight, was observed. In 4 of 23 (17%) patients, surgical revision was required because of a DFT increase >20 J during regular DFT testing. No complications regarding DFT testing were noted. CONCLUSIONS: After extracardiac ICD placement in infants and small children, DFT increase related to body length was evident during mid-term follow-up. Routine serial DFT testing was a safe procedure and identified a significant DFT increase in 4 of 23 patients. Serial DFT testing during follow-up in these patients is recommended.

Performance of automated external defibrillators under conditions of in-flight turbulence.

INTRODUCTION: Modern automated external defibrillators (AEDs) are designed to prevent shock delivery when excessive motion produces rhythm disturbances mimicking ventricular fibrillation (VF). This has been reported as a safety issue in airline operations, where turbulent motion is commonplace. We aimed to evaluate whether all seven AEDs can deliver shock appropriately in a flight simulator under turbulent conditions. METHODS: The study was performed in a Boeing 747-400 full motion flight simulator in Hong Kong. An advanced life support manikin and arrhythmia generator were used to produce sinus rhythm (SR), asystole, and five amplitudes of VF, with a programmed change to SR in the event of an effective shock being delivered. All rhythms were tested at rest (no turbulence) and at four levels of motion (ground taxi vibration, and mild, moderate and severe in-flight turbulence). Success was defined as: 1. effective shock being delivered where the rhythm was VF successfully converted to SR; 2. no inappropriate shock being delivered for asystole or SR. RESULTS: Five AEDs produced acceptable results at all levels of turbulence. Another was satisfactory for VF except at very fine amplitudes. One model was deemed unsatisfactory for in-flight use as its motion detector inhibited shocks at all levels of turbulence. CONCLUSION: Some AEDs designed primarily for ground use may not perform well under turbulent in-flight conditions. AEDs for possible in-flight or other non-terrestrial use should be fully evaluated by manufacturers or end-users before introduction to service.