What do you think is the reason?
Although we have a general knowledge that a person that started to become cyanotic must have oxygen. This is true, but we need to know the cause of that problem.
A patient that is suffering from peripheral cyanosis does indeed have enough oxygen in their blood. If you are going to check their physical saturation, you will notice that the SPO2 is almost 98-100%. Now, you will think what is wrong with your patient.
Lack of oxygen in the extremities or phalanges or fingers/toes
If unattended after referral assess patient from cephalo-caudal
Check for clubbing of fingers
Check for capillary refill