2015 AHA Guidelines Summarized

2015 AHA CPR & ECC Guidelines Update

Every five years the American Heart Association releases updates to its Guidelines for CPR and Emergency Cardiac Care (CPR & ECC). The 2015 updates were just released and can be found here. If reading tons of text in PDFs isn’t your jam, don’t fear. We’ve got you covered for what’s new in terms of BLS and adult ACLS.

First and foremost, however, we’ve got to reminder that these are Guidelines. As future resuscitationists, we need to understand the data behind each recommendation in order to best evaluate if the guidelines are applicable to the patient at hand. So, how do we evaluate the data? Ideally, we would read every paper cited in the guidelines and thoughtfully consider the study design and results of each. The AHA has helped us out, however, and graded each guideline based on how strongly they recommend it and the quality of evidence supporting it.

This is Table 1 from the 2015 Guidelines which shows us how they break it down:

 

 

On the left you see the different ‘strengths’ of the recommendation. You’ll note that the words used are chosen carefully. Strong recommendations use terms like “is recommended” or “is encouraged”, moderate recommendations hedge by saying “is reasonable” or “can be useful”. Weak recommendations, however, are prefaced by “may be considered”. On the right, you will see the AHA expert panel’s grading of the evidence used to create each recommendation. Level A data is the best, consisting of high quality randomized controlled trials. Level B-R includes randomized trials of moderate quality, B-NR are non-randomized trials, C-LD include trials with limited data and C-EO are recommendations made without any data at all, rather are just expert opinion. Of course, it is difficult to standardize the measurement of subjective quality of different trials, and as always, the best way to know for sure is to read the data yourself.

Chain of Survival

Previously, the Chain of Survival was the same for both in- and out-of-hospital cardiac arrest. The 2015 guidelines have updated this by creating 2 separate chains, reflecting the inherent differences in management between these two events. As always, remember that the chain is no stronger than its weakest link. Each aspect of this chain is crucially important.For In Hospital Cardiac Arrest, the first link in the chain, symbolized by the magnifying glass, represents appropriate surveillance and prevention (think rapid response teams), the phone represents prompt notification and response to a multidisciplinary team of providers, the third link indicates high-quality CPR, followed by prompt defibrillation and, finally, ACLS when appropriate.Out of Hospital Cardiac Arrest is slightly different. Here, the first link is the recognition of arrest and call for help by bystanders. This is followed by early CPR initiation and defibrillation, hopefully performed by the bystander him or herself. Fourth is assumption of care by EMS providers who then transport the patient to the ED or cath lab, and eventually the ICU.

 

Adult Basic Life Support

BLS providers are divided into three levels: 1) Untrained Lay Rescuer who receives BLS instructions from dispatcher, 2) Trained Lay Rescuer, and 3) Healthcare Provider.

70% of out of hospital cardiac arrests (OHCA) occur in the home, with ~50% unwitnessed. 10.8% of adult patients with nontraumatic OHCA who receive resuscitative efforts from EMS survive to hospital discharge. An interesting update is Ubiquitous presence of mobile phones allow rescuer to activate emergency response system without leaving victim’s side

In general, BLS algorithm from 2010 and BLS fundamentals are unchanged:

  • Immediate recognition of sudden cardiac arrest (and stroke)
  •  Activation of emergency response system
  •  Early CPR
  •  Rapid defibrillation with AED
  •  Data continues to show that high-quality CPR improves survival. What is high quality CPR?
  • Adequate rate
  • Adequate depth
  • Allow full chest recoil
  • Minimize interruptions
  • Avoid excessive ventilation
  • See table below for updated recommendations with new recommendations in red text.

Pediatric Basic Life Support

The AHA defines infants as younger than 1 year of age. Children are defined as 1 year until puberty, which in females is defined as breast development and in males is the presence of axillary hair. Beyond puberty the adult guidelines mentioned above are used.

This change from compression rates of at least 100 beats per min to the addition of an upper limit of 120 beats per minute is based off data that higher rates are actually associated with adverse outcomes, perhaps because this does not allow enough time for full recoil and preload generation. These studies have not, however, been done in children and are instead extrapolated from adult data. Compressions only CPR

Many of the pediatric-specific recommendations were not reviewed in this iteration of the guidelines. Thus, we will continue to use the 2 finger technique for infant compressions and the 1 or 2 hand method for children. We still want to allow for full chest recoil and to use the head tilt-chin lift maneuver to open the airway (unless trauma is suspected, in which case the jaw thrust maneuver can be used when 2 rescuers are present) and to only check for pulselessness for 10 seconds or less (repeating every 2 minutes). Sole rescuers will continue to give 30 compressions followed by 2 breaths. If the child suffers a witnessed and sudden arrest, the arrest can be considered likely cardiac in nature (unless you have reason to believe otherwise), and in these cases the rescuer should immediately activate the emergency response system and retrieve an AED prior to initiating CPR. This is not the case if the arrest is respiratory in nature. Defibrillation in children should be done using an AED with a pediatric attenuator unless such an attenuator is not available, and manual defibrillation should be used in infants as opposed to AEDs.

1 rescuer Pediatric BLS ALgorithm

ADULT ACLS

As you can see, a huge chunk of the official ACLS guidelines (bradycardia/tachycardia WITH a pulse) were not addressed in this iteration of the guidelines. We’ll continue to use the same algorithms as prescribed per the 2010 guidelines. Additionally the numerical physiologic parameter targets were not reviewed. We will thus continue to aim for SCVO2 of > 30% and arterial relaxation diastolic pressure > 20mmHg based on the clinical setting.

 

Return of Spontaneous Circulation: ROSC

Much of the 2010 recommendations for ROSC were not reviewed this round. Here’s what’s new.

 

And that’s a wrap! I highly encourage you to read the guidelines for yourself - especially the parts that we did not summarize here. You can download them for free here!

This post was written by Vidya Eswaran, MSIV, and Julia Wang, MD/PhD Candidate, at BCM.