When to do CPR?
Timing is critical when recognising the need for, and starting, CPR. In general, if the brain is deprived of oxygen for longer than 4–6 minutes, some permanent damage, but not necessarily death, will occur.
When considering the need for CPR, remember:
• The time a person collapsed, was washed away in a river or was buried in an avalanche is not necessarily the time that their breathing or circulation stopped.
• People have been known to survive after long periods of submersion in cold water, so always attempt CPR even if you know the person has been underwater for some time.
Remember that CPR is done on a patient whose heart is not circulating blood and who is therefore essentially dead. You cannot make the patient’s situation worse, but by doing CPR, you may succeed in reviving them or maintaining them until emergency services arrive with an AED (automated external defibrillator).