Recognise arrest in under 10 s, start compressions immediately at 100-120/min and 5-6 cm depth, attach the defibrillator, and protect compression fraction.
At the bedside
Timed steps- 1
Recognise arrest
0-10 sUnresponsive and not breathing normally (gasping = arrest). Check for a carotid pulse for no more than 10 s. If in doubt, start CPR.
- 2
Call for help and the defibrillator
0 sShout for help, call the arrest team (in hospital) and bring the defibrillator/AED and arrest trolley. Note the time.
- 3
Start chest compressions
ImmediatelyLower half of the sternum, 100-120/min, 5-6 cm deep, full recoil, minimal leaning. Firm surface (CPR board or bed CPR mode).
- 4
Ventilate 30:2
Without airwayBag-valve-mask with 100% O2 and an oropharyngeal airway: 2 breaths over ~1 s each with visible chest rise, then 30 compressions.
- 5
Continuous compressions
With advanced airwayOnce intubated or SGA placed: continuous compressions and 1 breath every 6 s (10/min). Confirm tube with waveform capnography.
- 6
Attach pads and analyse
≤ 3 minPads on during compressions (right infraclavicular + left mid-axillary V6, or antero-posterior). Pause ≤ 10 s for rhythm check.
- 7
Swap compressors and check
Every 2 minChange compressor at each rhythm check to avoid fatigue. Aim for a compression fraction > 80%.
- 8
Monitor CPR quality
ThroughoutWaveform ETCO2: aim ≥ 10 mmHg and ideally ≥ 20 mmHg; a sudden rise (often > 10 mmHg jump) suggests ROSC. Arterial diastolic pressure if an arterial line is in place.
High-quality CPR targets
| Parameter | Target | Avoid |
|---|---|---|
| Rate | 100-120/min | < 100 or > 120 |
| Depth | 5-6 cm (adult) | < 5 cm or > 6 cm |
| Recoil | Full chest recoil | Leaning on the chest |
| Pauses | < 10 s for rhythm or pulse check, pre-shock pause < 5 s | Long pauses for intubation or IV access |
| Ventilation (no airway) | 30:2, ~1 s breaths, visible rise | Hyperventilation |
| Ventilation (advanced airway) | 10 breaths/min, continuous compressions | > 12/min |
| ETCO2 | ≥ 10 mmHg, ideally ≥ 20 mmHg | Falling ETCO2 = tiring compressor or poor CPR |
Arrest recognition to first rhythm check
Step 1 of ~4
Ensure safety; shout for help
Based on Part 7: Adult Basic Life Support: 2025 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care; European Resuscitation Council Guidelines 2025 Adult Basic Life Support. Educational use; follow local protocol.
Pathophysiology
Compressions generate cardiac output by direct cardiac and thoracic pump effects, producing at best 25-30% of normal output. Coronary perfusion pressure (aortic diastolic minus right atrial pressure) above ~15-20 mmHg is linked to ROSC, and it falls within seconds of stopping compressions. That is why pauses are so harmful.
Evidence
- AHA 2025 BLS and ERC 2025 BLS keep 100-120/min and 5-6 cm depth with full recoil.
- AHA 2025 ALS: 10 breaths/min with an advanced airway; waveform capnography is recommended to confirm and monitor tube placement; ETCO2 or arterial diastolic pressure may be used to monitor CPR quality; head-up CPR is not recommended outside trials.
- Compression fraction > 60-80% and shorter peri-shock pauses are associated with better survival in observational data.
Controversies
- Optimal ventilation strategy before an advanced airway (30:2 vs continuous compressions with asynchronous breaths).
- Mechanical CPR devices are not better than good manual CPR, but help during transport, PCI or prolonged resuscitation.
🇮🇳 India notes
- The Indian Resuscitation Council (IRC, a joint initiative led by the Indian Society of Anaesthesiologists) published BCLS and CCLS guidelines in 2017 adapted to Indian settings, and promotes compression-only life support for lay rescuers.
- Many Indian wards lack AEDs; place defibrillators on every floor and train nurses to defibrillate before the doctor arrives.
References
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