I have to do a yearly CPR update for my job (within the NHS). When I did it last year, it was 30 compressions to 2 breaths. This year (in July) it was compressions only for up to 5 minutes (after checking that the airway is clear) and then you can choose whether or not to give breaths. The reason they gave for only doing compressions was that there is enough oxygen in the blood stream and a small amount will be taken into the lungs because of the compressions. The also emphasised that it is your choice whether or not to give mouth to mouth after 5 mins. Some people may be reluctant to do it because of the risk of infection to themselves, and also if the patient has been sick it may put people off. A few days after the course I was on a train to Edinburgh to visit my parents and a passenger brought the guards attention to a man who wouldn't wake up. There was a bit of confusion as no-one knew him or how long he had been collapsed (it was a Friday evening commuter train, lots of people nod off after a long week at work), but it turned out that he had stopped breathing and his heart had stopped. One of the other passengers said that she thought she could feel a pulse and the guard phoned 999 and got advice from them to start cpr (compressions only). The ambulance crew arrived within a couple of minutes of us arriving at the next station and they immediately intubated him and continued CPR. I did feel that I should/could have done something, but because of the confusion and nobody actually asking for help I did not realise what was happening until the guard started CPR. Hopefully he was OK.