Basic Life Support The BMJ

1. Colchester Hospital University NHS Foundation Trust Colchester Essex UK

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Overview
* Early institution of CPR and defibrillation significantly increase the chance of survival after cardiac arrest

* Effective chest compression is vital, with correct depth and rate, and with a minimum of interruptions

* For the non-specialist, CPR on a child should follow the adult sequence of actions

Introduction
The term basic life support (BLS) is used to describe maintenance of a clear airway and support of breathing and the circulation in cases of cardiac arrest, without the use of equipment other than a simple airway device or protective shield. Cardiopulmonary resuscitation (CPR) is the combination of chest compression and rescue breathing, and forms the basis of modern BLS.

The chances of survival after cardiac arrest are increased when the event is witnessed and when a bystander institutes CPR prior to the arrival of the emergency services. When the heart arrests in ventricular fibrillation, the critical interval that determines outcome is the time from arrest until defibrillation, the chances of survival decreasing by between 7 and 10% for each minute of delay. Effective CPR reduces this decline by about 50%.

The best chance of a successful outcome for the patient is achieved if chest compressions are started as soon as cardiac arrest is diagnosed. Chest compressions should be given with minimal interruptions at the recommended rate and depth, and are accompanied by artificial ventilation according to the current guidelines (see Box 1 and Figure 1).

Figure 1 Adult basic life support. Reproduced with the kind permission of the Resuscitation Council (UK).

box 1 Optimal chest compression characteristics (adults)
* Depth 5–6 cm

* Rate 100–120 min−1

* Release …

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