Basic Life Support (BLS)

Last Updated on August 19, 2026

Danger

• Identify and make sure the is no danger at the surroundings

Response

• Tap on patient’s shoulder, and ask “Hello, are you okay?”
• Quick assessment at GCS level

Shout for Help

• Shout to call 999, get AED

Airway Assessment

• Look for any feature of upper airway obstruction

• Open airway – head tilt -chin lift / jaw thrust
• Remove any foreign body / obstruction in the mouth

Breathing Assessment

• Look for chest movement — Any chest rise? Equal bilaterally?

Circulation Assessment / CPR

• Check carotid pulse (5 – 10 seconds)
• If no pulse, proceed with chest compressions
• 30:2 — After every 30 compressions, give 2 rescue breath
• 2 or 5: Switch provider every 2 minutes OR every 5 cycles
• Check pulse every 2 minutes (take <10 seconds)

Defibrillation

• If no pulse, check for shockable rhythms with AED
• Shock if indicated
• 200 or 360: Biphasic defibrillator 200 J / monophasic defibrillator 360 J

• Continue CPR immediately after shock

Defibrillation VS Cardioversion

Further Reading

1. https://web.facebook.com/permalink.php?story_fbid=10156647641817523&id=740237522
2. Guide to the essentials in emergency medicine, 2nd ED
3. CPR update, MedTweet

Take Home Message

Remember these magic numbers for BLS:
100 – 120
5 – 6
30 : 2
2 or 5
10
200 or 360