The concept of double sequential defibrillation shocks was initially described in animal literature in a mid-1980s article presented in the Journal of American Cardiology. Using a canine model, investigators delivered single, double and triple exponential shocks to hearts in which v fib and myocardial infarction had been induced. The shocks were delivered one second apart and employed different vectors (i.e., pathways) across the heart. The researchers determined that “two sequential shocks over different pathways reduce both total energy and peak voltage required to terminate ventricular fibrillation.” Thus, both sequential shocks and multiple vectors help to reduce the v fib threshold and therefore terminate the arrhythmia.
DSED remains a potential exiting alternative therapy for patients presenting in refractory VF. Although controversy exists as to the mechanism of effect, current and future high-quality research trials may clarify the pragmatic effectiveness of DSED for refractory VF in the prehospital setting.
Interruptions in chest compressions during cardiopulmonary resuscitation can negatively impact survival. Several new endotracheal intubation (ETI) techniques including video laryngoscopy may allow for ETI with minimal or no interruptions in chest compressions.
In this study of CPR during out-of-hospital cardiac arrest, chest compressions were not delivered half of the time, and most compressions were too shallow. Electrocardiographic analysis and defibrillation accounted for only small parts of intervals without chest compressions.
The majority of clinical research is based on male testing subjects. The Heart and Stroke Foundation website contains an article called “Read the Spotlight on women”
Source: Heart and Stroke Foundation