100%. CPR initiated within 2 minutes of cardiac arrest increases survival rate by 81%. The fact that CPR is rarely initiated so quickly (and thus survival rates are extremely low), says nothing about the efficacy of CPR. In the best cases where CPR is initiated < 2 mins, and AED shock within < 5mins survival rate can be as high as 50%.
Cardiac arrest is an incredibly heterogenous condition. A witnessed VF arrest in a young person with an inherited electrical type heart condition who gets compressions and a shock on a gym basketball court can wake up and walk away normal. A 98 year old who codes from sepsis or a fentanyl OD who is profoundly hypoxic or acidemic who gets enough Narcan and CPR to start having a heartbeat again after 15 minutes is very different. The statistics reflect this but you can’t generalize from the general to the specific in this case.
https://newsroom.heart.org/news/bystander-cpr-up-to-10-minut...