ALS Providers and AED during Cardiac Arrest

[Aidey]

It's always been the case that those at the BLS level can do basic cardiac rhythm monitoring they can only defibrillate in automatic mode.

I'm confused. Where has it always been that those at the BLS level can do basic cardiac rhythm monitoring?

I think there are probably several reasons behind it:

1) It's not really necessary, if it is deemed acceptable that somebody on the street to use an AED in a resuscitation then it's acceptable that BLS people use one.

2) It is very unlikely that a cardiac arrest will be solely managed by BLS people

3) It would increase training and risk

I'm very confused.

 

[NomadicMedic]

Basics are not, as a rule, taught anything about cardiac monitoring. Way back in the day I was certified as an EMT-D and could use the LP-5 to shock rhythms in arrests, but that was an add on skill, made mostly obsolete by the availability of AEDs.

It may still be taught in some areas, but not as a part of the basic national curriculum.

In addition, the amount of "hands off the chest time" can directly impact the effectiveness of compressions. If you believe an extra 10 seconds of no compressions isn't detrimental to resuscitation, you're mistaken. On the phone now, but I'll pull the citations in a bit that show the most effective CPR is that which is done with minimal interruptions. And an extra 10 or 20 seconds every time you analyze a rhythm is not a minimal interruption.

 

[Aidey]

Basics are not, as a rule, taught anything about cardiac monitoring. Way back in the day I was certified as an EMT-D and could use the LP-5 to shock rhythms in arrests, but that was an add on skill, made mostly obsolete by the availability of AEDs.

You do realize just how much you are dating yourself right?

In addition, the amount of "hands off the chest time" can directly impact the effectiveness of compressions. If you believe an extra 10 seconds of no compressions isn't detrimental to resuscitation, you're mistaken. On the phone now, but I'll pull the citations in a bit that show the most effective CPR is that which is done with minimal interruptions. And an extra 10 or 30 seconds every time you analyze a rhythm is not a minimal interruption.

I've seen the same data, and I do want to make it clear I'm not advocating for of the use of AED mode as a routine thing. Just as a temporary option if you only have a couple of people on scene.

 

[Christopher]

It may still be taught in some areas, but not as a part of the basic national curriculum.

Basic cardiology is taught, which includes rudimentary explanations of the electrical systems and the conduction network. So, in theory EMT's should know what VF/VT are, but not necessarily what they look like on a surface ECG.

In addition, the amount of "hands off the chest time" can directly impact the effectiveness of compressions. If you believe an extra 10 seconds of no compressions isn't detrimental to resuscitation, you're mistaken. On the phone now, but I'll pull the citations in a bit that show the most effective CPR is that which is done with minimal interruptions. And an extra 10 or 30 seconds every time you analyze a rhythm is not a minimal interruption.

Don't worry, I've got this!

Berg RA, et al. Adverse Hemodynamic Effects of Interrupting Chest Compressions for Rescue Breathing During Cardiopulmonary Resuscitation for Ventricular Fibrillation Cardiac Arrest. Circ 2001;104:2465-2470. (Link)

Conclusions—Interrupting chest compressions for rescue breathing can adversely affect hemodynamics during CPR for VF.

Eftestol T, Sunde K, Steen PA. Effects of Interrupting Precordial Compressions on the Calculated Probability of Defibrillation Success During Out-of-Hospital Cardiac Arrest. Circ 2002;105:2270-2273. (Link)

Methods and Results—The probability of ROSC after a shock was continually determined from ECG signal characteristics for up to 20 seconds of 634 such hands-off intervals in patients with ventricular fibrillation. In hands-off intervals with an initially high (40% to 100%) or median (25% to 40%) probability for ROSC, the probability was gradually reduced with time to a median of 8% to 11% after 20 seconds (P 0.001). In episodes with a low initial probability (0% to 25%; median, 5%), there was no further reduction with time.

Yu T, et al. Adverse Outcomes of Interrupted Precordial Compression during Automated Defibrillation. Circ 2002;106:368-372. (Link)

Conclusions—Interruptions of precordial compression for rhythm analyses that exceed 15 seconds before each shock compromise the outcome of CPR and increase the severity of postresuscitation myocardial dysfunction.

Edelson DP, et al. Effects of compression depth and pre-shock pauses predict defibrillation failure during cardiac arrest. Resus (2006);71:137-145. (PubMed)

CONCLUSIONS: The quality of CPR prior to defibrillation directly affects clinical outcomes. Specifically, longer pre-shock pauses and shallow chest compressions are associated with defibrillation failure. Strategies to correct these deficiencies should be developed and consideration should be made to replacing current-generation automated external defibrillators that require long pre-shock pauses for rhythm analysis.

Pytte M, et al. Comparison of hands-off time during CPR with manual and semi-automatic defibrillation in a manikin model. Resus (2007);73:131-136. (PubMed)

RESULTS: Median time from last chest compression to shock delivery (with interquartile range) was 17s (13, 18) versus 11s (6, 15) (mean difference (95% CI) 6s (2, 10), p=0.004). Similarly, median time from shock delivery to resumed chest compressions was 25s (22, 26) versus 8s (7, 12) (median difference 13s, p=0.001) in the AED and MED groups, respectively.

Christenson J, et al. Chest Compression Fraction Determines Survival in Patients with Out-of-Hospital Ventricular Fibrillation. Circ 2009;120:1241-1247. (Link)

Conclusions—An increased chest compression fraction is independently predictive of better survival in patients who experience a prehospital ventricular fibrillation/tachycardia cardiac arrest.

Sell RE, et al. Minimizing pre- and post-defibrillation pauses increases the likelihood of return of spontaneous circulation (ROSC). Resus (2010);81:822-825. (PubMed)

Conclusions: Decreasing pre- and post-shock compression intervals increases the likelihood of ROSC in OOHCA from VF.

Cheskes S, et al. Perishock Pause: An Independent Predictor of Survival from Out-of-Hospital Shockable Cardiac Arrest. Circ 2011;124:58-66. (Link)

Conclusions—In patients with cardiac arrest presenting in a shockable rhythm, longer perishock and preshock pauses were independently associated with a decrease in survival to hospital discharge. The impact of preshock pause on survival suggests that refinement of automatic defibrillator software and paramedic education to minimize preshock pause delays may have a significant impact on survival.

The list continues.......I may or may not have researched this for something

 

[NomadicMedic]

Thanks Christopher. It's such a pain trying to list citations with my big fat thumbs.

 

[EMSrush]

Nice, Christopher. Bravo!

 

[Jon]

Thanks Christopher. It's such a pain trying to list citations with my big fat thumbs.

Nice, Christopher. Bravo!

Yup.

What he lacks in post quantity, he more than makes up for in quality. Thanks a lot!