New life support quiz

The actual correct sequence is Danger Response Send for help Compressions Airway Breathing. The ‘S’ was added in 2011 but unfortunately the ‘ABC’ sequence was not changed in the acronym did not change from DRSABC as this was thought to be potentially confusing for people already familiar with the ‘ABC’ sequence.

2 breaths should be given initially. Old BLS guidelines advocated 5 initial breaths.

In paediatric cardiac arrest with a shockable rhythm the defibrillator energy setting is 4J/Kg.

The effectiveness of defibrillation in terminating VF decreases by about 15% for each minute of delay.

Precordial thump is only indicated in monitored VF as if applied to pulseless VT it could precipitate VF (although pVT is only 2% of shockable rhythms). It delivers about 10-20J of energy and appears to be more effective in victims of high voltage electrocution, making it useful in mass arrests due to lightning strike.

The estimated circulation time of drugs given in cardiac arrest is about 90 seconds with CPR in progress.

Amiodarone cannot be given via ETT.

The pulse can be palpated as often as you like during CPR, however stopping CPR to perform a rhythm check should only occur 2 minutes after each intervention in ACLS, and not at all in BLS. The rhythm should be analysed for no longer than 10 seconds in normothermic patients, and 5 seconds is usually plenty.

Pulseless VT comprises approximately 1-2% of shockable rhythms in out of hospital cardiac arrest in adults. So shockable rhythms are nearly all VF.

In advanced prehospital systems such as Australia and New Zealand, the median time to defibrillation for shockable rhythms is approximately 7 minutes. This means there is significant organ hypoxia and acidosis that is not present in in hospital witnessed cardiac arrests.

Effective cardiac compression to maintain coronary perfusion is the most important of the choices given. Oxygenation is important, however coronary perfusion of poorly oxygenated blood is still better than no coronary perfusion of highly oxygenated blood. Ventilation is usually only required to maintain oxygenation, whilst restoration of normal acid base status is probably of no benefit and possibly harmful. Hypothermia may have a role to play following ROSC from ventricular fibrillation, but is never an initial priority.

In adult cardiac arrest with a shockable rhythm the second dose of adrenaline should be given at 6 minutes after CPR has commenced.

A 10-20% reduction in compression depth occurs by 90 sec., despite operators not necessarily feeling fatigued. This is the reason that changing operators at least every 2 minutes (usually at the time of rhythm check) is required.

Early intubation is most likely harmful as some interruption of CPR is usually required. It is best deferred until the patient fails to respond to initial CPR and defibrillation attempts or demonstrates ROSC. Chest compressions should only be ceased at the time the intubator is about to insert the laryngoscope into the patient’s mouth and intubation should be achieved within 10 seconds. The initial dose of adrenaline is 1mg, repeated every 2 minutes.