BLS - Adult Resuscitation 

Updated: Mar 21, 2014
  • Author: James J Lamberg, DO; Chief Editor: Meda Raghavendra (Raghu), MD  more...
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Basic Life Support (BLS): Adult Algorithm

1. Check responsiveness; if none, follow steps below [1, 2, 3]

  • Activate emergency response system
  • Get automated external defibrillator (AED)

2. Check pulse for < 10 seconds; if no pulse, follow steps below

  • Start high-quality cardiopulmonary resuscitation (CPR) at a compressions-to-breaths ratio of 30:2
  • Every 2 minutes, check pulse, check rhythm, and switch compressors
  • High-quality CPR and changing rescuers every 2 minutes improves a victim’s chance of survival

3. Attach AED as soon as available; if shockable rhythm, defibrillate and then immediately start CPR


See the list below:

  • Check pulse at carotid artery
  • Compression landmarks: Lower half of sternum between the nipples
  • Compression method: Heel of one hand, other hand on top
  • Depth: At least 2 in (5 cm)
  • Allow complete chest recoil after each compression
  • Compression rate: At least 100/min
  • Compression-to-ventilations ratio, 30:2
  • Continuous compressions if advanced airway present
  • Rotate compressor every 2 minutes
  • Minimize interruptions in compressions to < 10 seconds
  • Avoid excessive ventilation
  • If end-tidal carbon dioxide tension (PETCO 2) < 10 mm Hg, attempt to improve CPR quality
  • If diastolic pressure < 20 mm Hg, attempt to improve CPR quality


See the list below:

  • Head tilted, chin lifted
  • Jaw thrust if trauma suspected


See the list below:

  • Ventilation with advanced airway every 6-8 seconds asynchronous with compressions
  • Rescue breathing ever 5-6 seconds
  • Deliver at about 1 second/breath
  • Watch for visible chest rise


See the list below:

  • Attach and use AED as soon as available
  • Minimize interruptions in chest compressions before and after shock
  • Resume CPR beginning with compressions immediately after each shock