MillennialGunslinger; to be honest, I don't know what the studies show in regard to CPR with ventilations. I do know that when someone goes down in cardiac arrest, the people standing right there, where and when it happened, are probably the only chance that person has to survive.
I worked at a department where we would receive an alarm and we had two minutes to be driving out the barn doors. It didn't matter if you were on the toilet, in the shower, eating dinner, or asleep; you had two minutes to be enroute to the call. If you made that time limit 9999 times in a row and on the 10,000th time you took three minutes, dispatch would notify the Battalion Chief any time of the day or night and he would be on the phone when you got back to the station wanting to know why it took you three minutes to respond. Over 90% of the time we arrived on-scene within 8 minutes of the time of alarm. Again, you could be asleep and eight minutes later you were walking up to the door of the house. This is an excellent response time. You won't get that most places. But as good as that is, if you look at the statistics, 8 minutes is too long. That victim of cardiac arrest needs help immediately. Even with an 8 minute response time, if nobody did anything prior to our arrival, we can start all the IVs, give all the drugs....................and the patient has a VERY slim chance of survival. The bystanders are the key link in the chain. They MUST step up and act if this guy is going to make it.
In EMS, the phrase "Trauma is a surgical disease" means: you have to load and go. You can't stay and play. We can apply dressings, do needle chest decompressions, start IVs and all that stuff, but if you delay transport to do any of that; you are not increasing the patient's chance of survival; you are decreasing their chance of survival by delaying the time it takes to get them to an OR. You still do the IVs, you still stop the bleeding, you still do all that stuff, but you do it on the way to the hospital. Again, where I spent the majority of my career your on-scene time was also closely monitored by several different agencies. If you were on-scene longer than two or three minutes, there had better be a good reason why stated in your report. And these patient's need to go to a Level 1 Trauma Center: just getting them to any old ER isn't good enough. The receiving hospital has to have a full surgical team available 24/7/365. I have seen critical trauma patients where they were being wheeled into an OR within 15 minutes of the time of alarm. That includes the EMS response time, on scene time, driving to the hospital and a brief exam in the ER.