Ristagno Giuseppe, Milan
- Coarse VF responds well to defibrillation; intermediate and fine VF – not as well
- Defibrillation failure approaches ~75% during CPR
- Current shockable algorithm considers all shockable situations the same and uses the time approach (Shock –> 2 min CPR –> Shock)
- Recurrent VF /Resistant VF–> multiple defib attempts –> worse myocardial dysfunction post ROSC. Improving defib success will reduce the number of attempts and the post ROSC myocardial dysfunction
- ECG waveform analysis during CPR can be used to individualize defibrillation attempts to improve success
- AMplitude Spectrum Area (AMSA), one such technique, gives the area under the amplitude and frequency curve obtained from rhythm analysis during CPR
- Higher the AMSA –> higher are the chances of successful defibrillation
- With good chest compressions AMSA improves over time –> improved defibrillation success
- AMSA >15.5 predicts defibrillation success and <6.5 predicts failure
- Immediate vs delayed Defib in shockable rhythm – no superiority of one approach over the other (Cochrane meta-analysis – 2014)
- AMSA trial ongoing. Analysis of data from the first 30 patients – quite promising (see screen shot below)
- This might change the way we defibrillate in future!