27-09-21 - BLS

Question 1

What is the success rate of bystander CPR?

Answer 1

• 30-day survival rate is 10.5% for those that received CPR before arrival of emergency services
• 4.5% for those that did not

Question 2

How much air per rescue breath should you give the casualty?

Answer 2

• Enough volume to make the patient’s chest rise (around 700ml)

Question 3

Why should a single rescuer leave the casualty after initial assessment to get help?

Answer 3

• Chest compressions are very tiring so it is beneficial to have more than one person so you can swap.
• 1 person needs to secure the mask on the casualty while the other squeezes air into the lungs.
• One person needs to leave, contact emergency services, and get an AED (automated external defibrillator

Question 4

4) What is the percentage of oxygen in:
• Air
• Expired air

Answer 4

• Air – 21%

* Expired air – 16%

Question 5

BLS guide for non-medical person talks of “signs of life”. Describe these.

Answer 5

• Consciousness
• Effective breathing – casualty is breathing on their own without difficult
• Circulation – Casualty has a pulse
• Skin characteristics – Skin is not discoloured. Cyanosis is the bluish discoloration of the skin due to poor circulation or inadequate oxygenation of the blood.