Survival with a CPC score of @ or @ occurred in @ ( @ % ) vs @ ( @ % ) ( risk difference , @ % ; @ % CI , -@ % to @ % ) at intensive care unit discharge , in @ ( @ % ) vs @ ( @ % ) ( risk difference , @ % ; @ % CI , -@ % to @ % ) at hospital discharge , in @ ( @ % ) vs @ ( @ % ) ( risk difference , @ % ; @ % CI , -@ % to @ % ) at @ month , and in @ ( @ % ) vs @ ( @ % ) ( risk difference , @ % ; @ % CI , -@ % to @ % ) at @ months with mechanical CPR and manual CPR , respectively .