Without evidence of benefit, an intervention should not be presumed to be beneficial or safe.

- Rogue Medic

Why Did We Remove Atropine From ACLS? Part I

 

As of 2010, atropine is gone from the ACLS (Advanced Cardiac Life Support) treatment guidelines and nobody seems to be upset. We never had good evidence to support treatment of dead people with atropine, but we practiced this witchcraft because we chose optimism over evidence.

Some people claim that the constant changes to ACLS are evidence that evidence does not work.

That is not true. We ignored the lack of valid evidence. We chose to be ignorant.
 

We keep changing guidelines as we keep learning more. We should require valid evidence before adding treatments to guidelines, but too many of us are overly optimistic about treatments that are not supported by valid evidence. We believe that this time will be different. After we study treatments, we generally find out that we have been harming more patients than we have been helping.

Atropine is one example.

Look at all of this evidence of benefit.
 


Click on images to make them larger.[1]
 

What do the LOE (Level Of Evidence) and Good, Fair, and Poor categories mean?
 

The LOEs were subdivided into three major categories, depending on the type of question being asked: intervention, diagnosis, or prognosis. The quality of evidence categories were reduced from five categories in 2005 to three (good, fair, poor) in 2010.[2]

 

There is no further explanation of how Good, Fair, and Poor were to be decided, but there is an explanation of what the LOEs mean.

Level A is the evidence least likely to be misleading –
 


 

Level B is evidence that is much less likely to provide an accurate representation of the true effect of the intervention, because there are many more variables that are not controlled for –
 


 

Level C is the lowest evidence possible and even includes a category that is not really evidence – Expert Opinion
 


 

Expert Opinion is lower than the lowest of the low evidence.

In the chart Evidence Supporting Clinical Question, there is no column for expert opinion, because there is no good reason to include expert opinion in the analysis of evidence.
 

But what about the evidence that is there supporting the use of atropine?

Why is everything poor evidence?

Why isn’t there anything better than LOE 3: Studies using retrospective controls?

If the most positive study was back in 1984, and it was only LOE 3, why did we only remove atropine from the cardiac arrest guidelines in 2010?

The supporting evidence is not the only evidence, but that is not a good answer to my question.

The weak evidence in support of atropine in cardiac arrest is more than matched by stronger evidence that atropine does nothing useful –
 


 

There is also weak evidence that atropine is harmful –

 


 

How did atropine ever make it into the ACLS guidelines based on such poor evidence?
 

To be continued in Part II and Part III.

Footnotes:

[1] Atropine for cardiac arrest
2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science
Appendix: Evidence-Based Worksheets
Part 8 ALS
ALS-D-024B
Swee Han Lim
Evidence-Based Worksheet Download in PDF format.

That link is no longer available, but the overall page of evidence-based worksheets is available in PDF format here.

[2] Classification of Evidence
2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science
Part 2: Evidence Evaluation and Management of Potential or Perceived Conflicts of Interest
Evidence Evaluation Process
Free Full Text from Circulation.

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Comments

  1. Atropine is no longer part of ACLS?

    …said every ALS first responder I’ve ever run a code with.

  2. Another important question…why are we even attempting resuscitation on many of the patients we encounter in sudden cardiac arrest. Many of these lives are not savable, yet it’s all hands on deck for a wasted heroic effort. We dump tons of resources in to a futile effort. Shouldn’t we be applying our resources where they are needed most, rather than on an octogenarian with multiple medical problems and stage 4 cancer?

  3. Rogue,

    Shouldn’t the title be “Why Did We Remove Atropine From CARDIAC ARREST in ACLS? Part I”? I thought I’d missed a significant revision to the ACLS bradycardia algorithm.

    • Chris,

      Shouldn’t the title be “Why Did We Remove Atropine From CARDIAC ARREST in ACLS? Part I”? I thought I’d missed a significant revision to the ACLS bradycardia algorithm.

      Yes.

      Where I have mentioned it outside of the title, I have been pretty careful to mention that it has only been removed from cardiac arrest.

      I guess I wasn’t paying attention when I wrote the title.

      .

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