Cardiopulmonary resuscitation (CPR) consists of alternating cycles of chest compressions and rescue breaths at a 30 compressions to 2 rescue breaths ratio (30:2). One ‘cycle’ of CPR is equivalent to one round of 30:2.
Rescuers are recommended to switch over after conducting 2 minutes of CPR in order to guarantee that their chest compressions stay successful (delivered at the correct depth and speed).
If you perform chest compressions at the proper tempo, you should be able to conduct roughly 5 cycles of CPR in 2 minutes (minimum of 100 chest compressions per minute). The rate at which chest compressions are performed is critical in order to move blood around the body. Slow chest compressions are unlikely to be successful.
As a general rule, rescuers should aim for approximately 5 cycles of CPR before switching over. They should keep switching until expert medical help comes.
Learn more about CPR by attending one of our first aid training courses.