|Title||Association of amplitude spectral area of the ventricular fibrillation waveform with survival of out-of-hospital ventricular fibrillation cardiac arrest.|
|Publication Type||Journal Article|
|Year of Publication||2014|
|Authors||Indik JH, Conover Z, McGovern M, Silver AE, Spaite DW, Bobrow BJ, Kern KB|
|Journal||J Am Coll Cardiol|
|Date Published||2014 Sep 30|
|Keywords||Adult, Aged, Area Under Curve, Arizona, Cardiopulmonary Resuscitation, Databases, Factual, Defibrillators, Electric Countershock, Female, Humans, Logistic Models, Male, Middle Aged, Out-of-Hospital Cardiac Arrest, Patient Admission, Patient Discharge, Retrospective Studies, Sensitivity and Specificity, Ventricular Fibrillation|
BACKGROUND: Previous investigations of out-of-hospital cardiac arrest (OHCA) have shown that the waveform characteristic amplitude spectral area (AMSA) can predict successful defibrillation and return of spontaneous circulation (ROSC) but has not been studied previously for survival.
OBJECTIVES: To determine whether AMSA computed from the ventricular fibrillation (VF) waveform is associated with pre-hospital ROSC, hospital admission, and hospital discharge.
METHODS: Adults with witnessed OHCA and an initial rhythm of VF from an Utstein style database were studied. AMSA was measured prior to each shock and averaged for each subject (AMSA-avg). Factors such as age, sex, number of shocks, time from dispatch to monitor/defibrillator application, first shock AMSA, and AMSA-avg that could predict pre-hospital ROSC, hospital admission, and hospital discharge were analyzed by logistic regression.
RESULTS: Eighty-nine subjects (mean age 62 ± 15 years) with a total of 286 shocks were analyzed. AMSA-avg was associated with pre-hospital ROSC (p = 0.003); a threshold of 20.9 mV-Hz had a 95% sensitivity and a 43.4% specificity. Additionally, AMSA-avg was associated with hospital admission (p < 0.001); a threshold of 21 mV-Hz had a 95% sensitivity and a 54% specificity and with hospital discharge (p < 0.001); a threshold of 25.6 mV-Hz had a 95% sensitivity and a 53% specificity. First-shock AMSA was also predictive of pre-hospital ROSC, hospital admission, and discharge. Time from dispatch to monitor/defibrillator application was associated with hospital admission (p = 0.034) but not pre-hospital ROSC or hospital discharge.
CONCLUSIONS: AMSA is highly associated with pre-hospital ROSC, survival to hospital admission, and hospital discharge in witnessed VF OHCA. Future studies are needed to determine whether AMSA computed during resuscitation can identify patients for whom continuing current resuscitation efforts would likely be futile.
|Alternate Journal||J. Am. Coll. Cardiol.|
Association of amplitude spectral area of the ventricular fibrillation waveform with survival of out-of-hospital ventricular fibrillation cardiac arrest.
Bentley J. Bobrow, MD, FACEP, FAHA
Daniel W. Spaite, MD