Impedance Threshold Device Combined With High-Quality Cardiopulmonary Resuscitation Improves Survival With Favorable Neurological Function After Witnessed Out-of-Hospital Cardiac Arrest.
BACKGROUND
The quality of cardiopulmonary resuscitation (CPR) has been recently shown to affect clinical outcome. The Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation Impedance Valve and Early Versus Delayed Analysis (PRIMED) trial showed no differences in outcomes with an active vs. sham impedance threshold device (ITD), a CPR adjunct that enhances circulation. It was hypothesized the active ITD would improve survival with favorable neurological outcomes in witnessed out-of-hospital cardiac arrest patients when used with high-quality CPR.


RESULTS
Using the publicly accessible ROC PRIMED database, a post-hoc analysis was performed on all witnessed subjects with both compression rate and depth data (n=1,808) who received CPR within the study protocol definition of adequate CPR quality (compression rate 80-120/min and depth 4-6 cm; n=929). Demographics were similar between sham and active ITD groups. In witnessed subjects who received quality CPR, survival with favorable neurological function was 11.9% for the active ITD subjects (56/470) vs. 7.4% for the sham (34/459) (odds ratio 1.69 [95% confidence interval 1.08, 2.64]). There were no statistically significant differences for this primary outcome when CPR was performed outside the boundaries of the definition of adequate CPR quality. Multivariable models did not change these associations.


CONCLUSIONS
An active ITD combined with adequate-quality conventional CPR has the potential to significantly improve survival after witnessed cardiac arrest. (Circ J 2016; 80: 2124-2132).
Department of Pharmacology, Faculty of Medicine, Toho University.
Atsushi
A
Sugiyama
Sue
S
Duval
Yuji
Y
Nakamura
Katsunori
K
Yoshihara
Demetris
D
Yannopoulos
D000368:Aged; D000369:Aged, 80 and over; D016887:Cardiopulmonary Resuscitation / Q000295:instrumentation* / Q000379:methods*; D016208:Databases, Factual; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality* / Q000628:therapy*; D015996:Survival Rate