The little formula above is the one used during cardiopulmonary resuscitation and, in particular, just before delivering the discharge of a defibrillator to prevent anyone from touching the patient during this download.
But, in my previous article , it has been shown that some studies, particularly that of Lloyd et al , have highlighted how the currents passing through an operator during the discharge of an AED in cardioversion of atrial fibrillation are, under the conditions of that study, even below the threshold of perception of shock from the operators.
The question is: are we ready to remove the interruptions during the discharge phase of the DAE (hands-off) and continue to massage during this discharge (hands-on)?
To answer this important question, let's see what has happened in the literature after 2008 ie after the release of the results of the experiment of Lloyd et al.
A first answer to this doubt Hamlet is given by the study of Neumann et al, published in 2012 by the Journal of the American Heart Association, titled "Hands-on defibrillation Has the potential to Improve the quality of cardiopulmonary resuscitation and is safe for rescuers? In preclinical studies. "
In this study, Neumann et al seek to dispel some possible doubts experiment of Lloyd. First of all the fact that in this study the patients were in ventricular fibrillation, but atrial fibrillation (AF) was placed in doubt about whether a hands-on approach could have advantages or less of a hands-off approach .
In addition, the RCP experiment of Lloyd were simulated and so it was not clear whether even in the presence of a true cardiopulmonary resuscitation operators do not perceive the shock of the AED.
To answer these questions, the researchers took 20 (poor) piglets, divided them into two groups, have them sedated, placed under repeatable and sent them into ventricular fibrillation (VF). We carry the design of the setup of the experiment, present in the original, because it makes me laugh too
The first group was applied to a hands-off approach with the classic interruzzioni during the discharge of the AED while the second group has applied a hands-on approach without ever interrupting CPR if not during the analysis phase. I add
At the launch of ventricular fibrillation was then waited seven minutes without doing anything to simulate a ritarno in rescue then applying two minutes of BLS and ALS then proceeding with an approach with defibrillation and drug side continuing until the eventual return of spontaneous circulation ( ROSC ).
What were the results of the experiment? Level of return of ROSC, there were no significant differences, 9 out of 10 pigs in the group hands-on have returned to live compared to 8 of 10 in the second group. But, as stated by the authors themselves, this excellent result in both groups may be due to the minimum delay (only 7 minutes of VF) before they started resuscitation procedures. Perhaps, with the rescue time more dilated, the differences would have been greater.
Instead, what has impressed the authors is that hands-off group in the RCP were discontinued in 8.2% of the time versus 0.8% in the group hands-on. Since the interruption of CPR lead to a fall in coronary perfusion pressure and, before it returns to acceptable levels is necessary to "waste" a number of new CPR, this has resulted in the recovery time of this pressure (and therefore time CPR wasted) much smaller in hands-on group (1.9% of the time) than the hands-off (6.3%).
This has resulted in a peak concentration of lactate , after the return of ROSC, only 5 minutes in the group hands-on against more than two hours of hands-off group that symptom perfusion during CPR was much better in the first that in the second group.
With regard to the potential hazards to rescuers, this experiment showed that no operator, including those in the group hands-on, in the least warned the defibrillator will the Holter ECG that were set in order to assess their potential danger in heart rhythm rescuers have never detected any irregular or problematic nature of electricity.
For this reason, at the conclusion of the article, Neumann et al, recommend the following checklist for the use of an approach of CPR uninterrupted even during the discharge of the AED.
- If you're wearing polyethylene gloves
- if the defibrillator is biphasic
- if the plates of the defibrillator are self-adhesive and the outer part is covered with non-conductive material
- if the electrodes make good contact with the patient's skin
- if there are additional elements of danger (bodily fluids, rain, conductive surfaces)
then it is possible to think of a hands-on approach to the patient in cardiopulmonary arrest.
In the face of everything, always and forever in 2012 in the Journal of the American Heart Association comes out of an editorial from the emblematic title "Hands-on defibrillation, the end of" I'm clear, You're Clear, We're all Clear? ", written by Richard E. Kerber, from which I took the title of this article, which further emphasizes the interesting and impressive results of the experiments of Lloyd and Neumann but stresses the need for further study, perhaps leading time beginning of a BLS from 7 to 15 minutes to see if this lengthening of aid affects the return of ROSC between patients treated with a hands-on approach compared to those treated with a hands-off approach.
On the other hand, the editorial emphasizes again the need to focus attention on the primary safety conditions because of the rescuer, it is true that under the conditions of these experiments, the resistance offered by the rescuer to the passage of current were optimal (gloves latex, no presence of fluids or metal surfaces) shall also be true that often the real situation may not be as optimal and eventual passage of current through the body by a larger amount of the rescuer may have adverse effects.
The editorial closes with the following question. At present, we are ready to consider a revision of the guidelines for introducing the non-interruption of CPR during the discharge of the AED? The answer to that is obviously the author, on the basis of current knowledge, bad as they are obviously needed further investigation about the safety of this procedure for the rescuer and a clear decrease in the effective study of risk / benefit ratio in favor of this new approach.
As they say in these cases, who will live, will see.