Dual Sequential Defibrillation Research Articles

Exploring the power of prehospital dual sequential defibrillation in overcoming refractory cardiac arrest

Exploring the power of prehospital dual sequential defibrillation in overcoming refractory cardiac arrest

Current and investigational therapies for the treatment of refractory ventricular fibrillation.

Esmolol, dual sequential defibrillation, vector change defibrillation, and left stellate ganglion block are presented and reviewed for the treatment of refractory ventricular fibrillation. Although no formal definition has been established for refractory ventricular fibrillation, the literature describes it as a pulseless ventricular arrhythmia that persists despite 3 standard defibrillation attempts, administration of amiodarone 300 mg intravenously, and provision of three 1-mg intravenous doses of epinephrine. Evolving literature surrounding resuscitation in this particular subset of cardiac arrest challenges the efficacy of traditional therapies, such as epinephrine, and suggests that other treatment modalities may improve outcomes. Case reports, case series, and small retrospective studies have pointed to benefit when utilizing a variety of therapies, namely, esmolol, dual sequential defibrillation, vector change defibrillation, or left stellate ganglion block, in patients with refractory ventricular fibrillation arrest. A mounting, although limited, body of evidence suggests that esmolol, dual sequential defibrillation, vector change defibrillation, or left stellate ganglion block may be effective at terminating refractory ventricular fibrillation and improving patient outcomes. Further evidence is required before these therapies can be adopted as standard practice; however, as key members of the code response team, it is imperative for pharmacists to be familiar with the supporting evidence, safety considerations, and logistical challenges of utilizing these treatments during arrest.

Triple-sequential defibrillation for refractory ventricular fibrillation in a 24-year-old male out of hospital cardiac arrest.

SUMMARYRefractory ventricular fibrillation encountered during cardiac arrest has a mortality rate of 97%.1 As per the advanced cardiac life support (ACLS) guidelines, the management algorithm of ventricular fibrillation consists of chest compressions, epinephrine, defibrillation, and anti-arrhythmics.2 There have been reports describing the use of the fast-acting selective β-blocker, esmolol, and dual-sequential defibrillation in the management of ventricular fibrillation that is refractory to standard ACLS. We present a case of a 24-year-old male who had an out-of-hospital cardiac arrest, with refractory ventricular fibrillation despite high-quality cardiopulmonary resuscitation (CPR) and ACLS management. Along with standard ACLS, triple-sequential defibrillation was used to achieve return of spontaneous circulation (ROSC) after 82 minutes of downtime. An electrocardiogram (ECG) after ROSC showed an ST-elevation myocardial infarction (MI), and the patient underwent angiography showing a 100% occlusion of his left anterior descending artery. Following management of his coronary artery disease, he was discharged from the hospital 16 days later and was neurologically intact.

Dual Defibrillation is Highly Variable: An Analysis of Pulse Interval Delivered in Dual Defibrillation

Background: Dual defibrillation (DD) is a technique where two external defibrillators are applied with two different pad configurations and discharged to treat refractory ventricular fibrillation (RVF). Although commonly called dual sequential defibrillation (DSD), if the delivered electrical pulses overlap with no pulse interval, the shocks are actually dual simultaneous defibrillation (DSiD). Manual DD technique is not standardized and the effect that the method of activation has on the delivered pulse interval has never been studied. Objectives: This study measured the timing of four methods of DD and the resulting inter-shock intervals, frequency with which they were either DSiD or DSD, and frequency which the true DSDs delivered any previously reported optimum pulse interval. Methods: This was a single-blinded prospective evaluation of a convenience sample of volunteer physicians, nurses, and paramedics each performing DD in our simulation center on two types of defibrillators using four techniques: single operator-simultaneous with 2 hands (SOSI), two operators-simultaneous (TOSI), single operator-sequential with 1 hand (SOSE1), and single operator-sequential with 2 hands (SOSE2). Results: The four DD methods generated a variable set of pulse intervals depending on the technique and defibrillator employed. The pulse intervals ranged from 0 msec (i.e., overlapping waveforms or DSiD) to 1800 msec. Of all DD attempts, 85.9% met the definition of DSD, 14.1% were DSiD, and 49.4% delivered any one of the optimum pulse intervals previously described in the literature. SOSI and TOSI techniques resulted in DSD between 47.2 and 87.6% of the time, depending on the technique and defibrillator. Shocks delivered sequentially on purpose (SOSE2 and SOSE1) were always DSD but with widely variable pulse intervals. SOSI resulted in the shortest pulse intervals, SOSE1 resulted in the longest, and TOSI and SOSE2 were the least skewed. Conclusion: DD using the various methods currently employed produces a highly variable set of pulse intervals even within a single method. It is difficult to reach a conclusion about the efficacy of DD unless the delivered pulse interval is measured or the method of activation reproducibly produces a precise pulse interval.

Changing the management of refractory ventricular fibrillation: The consideration of earlier utilization of dual sequential defibrillation

Dual Sequential Defibrillation (DSD) has shown promise in the management of refractory ventricular fibrillation (RVF). In the recent past, there have been a number of reports on the topic with varying results. Some studies have concluded that DSD provides no benefit over standard defibrillation therapy of RVF in terms of survival and neurological outcome. In fact, termination of RVF and achieving return of spontaneous circulation (ROSC) are achieved quite frequently in patients with DSD. Unfortunately, DSD has been utilized very late in the course of resuscitation, likely masking a great deal of its potential benefit. Interventions at this later phase of resuscitation are much less likely to produce a beneficial outcome, regardless of their ability to impact the course of events. It is suggested that earlier use of DSD can potentially improve ROSC, ultimate survival, and neurological outcome. After a review of the existing literature on the topic, we will propose that DSD be considered for use at a much earlier time in the resuscitation of patients with RVF. In addition to the consideration of its use in resuscitation, clinicians and device manufacturers must also address the impact on the two defibrillation devices employed in DSD due to the potential for damage and resultant defibrillator dysfunction.

Effectiveness of Prehospital Dual Sequential Defibrillation for Refractory Ventricular Fibrillation and Ventricular Tachycardia Cardiac Arrest

Objective: Dual sequential defibrillation (DSD) — successive defibrillations with two defibrillators — offers a novel approach to refractory ventricular fibrillation (RVF) and tachycardia (VF/VT). While associated with rescue shock success, the effect of DSD upon out-of-hospital cardiac arrest (OHCA) is unknown. We evaluated the association of DSD with survival after refractory VF/VT OHCA. Methods: We used data from a large metropolitan fire-based EMS service. We included all adult OHCA during 2013–2016 with ≥3 standard defibrillations. Physicians authorized subsequent DSD use by two separate defibrillators (PhysioControl LIFEPAK® 12/15) with pads placed anterior-lateral and anterior-posterior. Evaluated outcomes included return of spontaneous circulation (ROSC), survival to hospital admission, survival to 72 hours, and survival to hospital discharge. Using multivariable logistic regression, we evaluated the association between defibrillation type and OHCA outcomes, adjusting for patient demographics and event characteristics. Results: We included 310 patients in the analysis, 71 patients receiving DSD and 239 receiving conventional defibrillation. Patient demographics and event characteristics were similar between both groups. ROSC was lower for DSD than standard defibrillation: 39.4% vs. 60.3%, adjusted OR 0.46 (95% CI: 0.25–0.87). There were no differences in survival to hospital admission (35.2% vs. 49.2%, adjusted OR 0.57 [95% CI: 0.30–1.08]), survival to 72 hours (21.4% vs. 32.3%, adjusted OR 0.52 [95% CI: 0.26–1.10]), or survival to hospital discharge (14.3% vs. 20.9%, adjusted OR 0.63 [95% CI: 0.27–1.45]). Conclusions: Compared with conventional defibrillation, DSD was associated with lower odds of prehospital ROSC. Defibrillation type was not associated with other OHCA endpoints. DSD may not be beneficial in refractory VF/VT OHCA.

Refractory Ventricular Fibrillation Successfully Cardioverted With Dual Sequential Defibrillation

BackgroundCurrent guidelines for the treatment of adult patients in cardiac arrest are supplied by the American Heart Association through basic life support and advanced cardiovascular life support (ACLS) provider courses. When treatments defined by the ACLS guidelines are unsuccessful in terminating a lethal dysrhythmia, the use of alternative strategies may prove useful. In this case, two defibrillators were used to deliver a greater than normal energy waveform over an extended time interval to return a patient to a normal sinus rhythm. Case ReportA 56-year-old woman presented to the emergency department with complaints of chest pain, nausea, and vomiting. The patient's initial work-up, including an electrocardiogram and cardiac troponin, did not show evidence of acute ischemia, and she was admitted to the observation unit for further evaluation. While in the emergency department, the patient developed ventricular fibrillation, and ACLS was initiated. After four unsuccessful defibrillation attempts, a second defibrillator was placed on the patient, and the two were activated almost simultaneously. The patient had immediate return of spontaneous circulation, underwent cardiac catheterization, and was discharged home 1 week later. Why Should an Emergency Physician Be Aware of This?This case shows that dual sequential defibrillation may be a successful method for terminating refractory ventricular fibrillation. Further investigation on cardiac resuscitation should be conducted to standardize the dual sequential defibrillation delivery procedure. Until such guidelines are established, physicians should take this treatment into consideration when standard ACLS measures have failed to successfully terminate refractory ventricular fibrillation.