Why do we send so many people to a cardiac arrest?


I did a fair amount of traveling and teaching in 2013 and I’ve been struck by the number of people who have been amazed by the number of rescuers my fire department sends to a sudden cardiac arrest (1 ambulance, 2 engines, and a battalion chief).

I think there are several reasons for this. In the first place, most jurisdictions don’t have the resources, or at least say they don’t have the resources, to do what we we do. But a larger issue is that people don’t understand the benefit of sending 7 to 11 people to a sudden cardiac arrest. In fact, some have argued that sending that many people only encourages therapies (like drugs and tracheal intubation) that have not been proven to positively effect neurologically intact survival. 

Aside from the fact that we identified this additional staffing on the first alarm as a best practice after speaking with some of the best EMS systems in the country (those few who can prove it), let’s look at the big picture.

First, we need to consider that sudden cardiac arrest, particularly witnessed VF arrest, is a survivable event — when a process is in place to save that life. Although I don’t take credit for the maxim, I have said many times that “every system is perfectly designed to achieve the results that it gets” and I certainly believe that. If the planets need to be in perfect alignment for a patient to survive in your system then it is not geared to save lives. Rather, it is geared to take patients to the hospital and generate revenue.

You might deliver excellent customer service, and you might have talented EMTs and paramedics, but no individual can save lives in a vacuum. Human performance is inexorably intertwined with system performance. Almost every young, highly intelligent, and motivated paramedic who becomes disillusioned with his or her EMS system is told, “just do the best you can in the back of your ambulance and make a difference with each and every patient you come into contact with.” You can try to do that, it’s true. I’ll even conceded that you can find some value or solice in doing that.

But you cannot reach your potential as a medical professional within a poorly performing system.

Poorly performing systems are almost never the fault of the guys and gals on the front lines. That’s true in factories, it’s true in the military, it’s true in hospitals, and it’s certainly true in EMS systems. You can achieve compliance with a whip but you cannot achieve quality. Once we accept that it’s all about the process, we can go about the task of designing processes to save lives.

The principles of the 2010 AHA ECC Guidelines are quite simple.

  • Minimally interrupted chest compressions
  • Controlled ventilations
  • Early defibrillation and shocking in a 2-minute cycle
  • Managing the peri-shock pause
  • Allowing capnography to identify ROSC
  • Early identification of STEMI and transport to a PCI center
  • Targeted temperature management

As they say in the Resuscitation Academy in Seattle, “it isn’t complicated but it’s not easy.” The reason it’s not easy is that while no individual piece is particularly complicated, making it all happen in a highly coordinated way involves a lot of different individuals who must work together as a team, and do so over and over again, with different team configurations.

The issue is variability — the enemy of system performance.

So why send so many people to a sudden cardiac arrest? Here are the benefits.

1.) Experience

You might have a brand new paramedic on the first arriving ambulance. But when you send multiple assets to the call you’re bound to get an experienced paramedic. I can already hear the objections from some of you about “skill dilution” (which I think pales in comparison to the modern problem of “never having the skill in the first place”). But, the reality is, leaving newer paramedics alone to experience clinical misadventure teaches them nothing, except perhaps “what happens in the back of the ambulance stays in the back of the ambulance”. Which brings me to the next point.

2.) Modeling

A very important, but initially unanticipated, side benefit to sending multiple crews to a cardiac arrest call is that each time we assemble our Pit Crew CPR process is an opportunity to model the correct behaviors for our personnel. We are able to reinforce our checklist-driven methodology that ensures that the appropriate leadership and communication take place, that we do not move patients in cardiac arrest prematurely, that we meet important benchmarks, and that we do so in a calm and organized fashion.


3.) Logistics

There is absolutely no reason that the first arriving crew to a sudden cardiac arrest should have to worry about locating the patient, carrying the cardiac monitor, airway bag, suction unit, drug box, a backboard, and a gurney onto the scene of a cardiac arrest, which could be on the 5th floor of a hotel. When you send enough appropriately trained people to a sudden cardiac arrest you can have people holding the elevator, interact with the family, run back to the ambulance, switch out the rescuer on chest compressions, take a 30,0000 foot view and act as a “code commander”, be a scribe, or just put another set of eyes on the process.

4.) Leadership

Taking command of a structure fire is considered so important that failure to do so is considered negligence in the fire service. The reason is simple. When we act as individuals (freelance) we get into trouble. There may be confusion about whether or not we are “offensive” or “defensive”, vital information may not be shared, dangerous ventilation practices can threaten interior teams, or there can be a catastrophic loss of situation awareness that leads to firefighter death or injury. Have you ever been on a call with three paramedics and seen them work separately as opposed to as a team? Someone must be in charge. That doesn’t mean someone reverts to Theory X and becomes unapproachable or dictatorial. It means that someone coordinates the team’s activities. To do this effectively on a system-wide basis requires specific training in Crew Resource Management which is outside the scope of this blog post.

5.) Supervision

When you send a supervisor to each and every resuscitation attempt it helps to ensure consistency from crew to crew and shift to shift. It also helps cut through any issues or problems you might have on scene. Our battalion chiefs often act as the family liaison, interact with law enforcement, nurses, or physicians on scene, make sure that policies are followed, and sometimes, even provide expert clinical care if the need arises. They are there to support the personnel who are engaged in the resuscitation, and they are there to monitor performance to identify opportunities for improvement.

In the beginning, there were plenty of paramedics who bristled at the idea of a Battalion Chief showing up for resuscitation attempts, and some of them thought a second engine was a ludicrous waste of time and money. No one feels that way anymore. In part, that’s because we measure our outcomes and the increase in neurologically intact survival, particularly in calendar year 2011, was undeniable. When you have 9 additional survivors who walked out of the hospital in a department the size of mine, it’s a big deal.

That’s pretty good for morale.

We have spent the last 20 or 30 years sending half the fleet to a “pot on the stove”. Now, everyone understands that a sudden cardiac arrest is just as important (actually far more important) than the average “smoke in a structure”. That’s a change in culture. There have been other changes, too. Like the idea that we provide supportive and non-punitive feedback to the line. It turns out that when you believe in people, provide the appropriate education and training, explain the “why”, give them the right tools to do the job, and support them, they rise to the occasion and do amazing things. They help build a process that saves lives and they take ownership of it. They should, because we can’t do it without them. It’s a human being that performs chest compressions, starts IVs, charges a defibrillator, and makes critical decisions.

A lot of people say “response times don’t matter” or “it’s such a small percentage of our call volume”. Well, to say the least statements like that require qualification. I find it to be far more palatable from an EMS system that knows its numbers and has optimized its system performance. Otherwise, we’re essentially writing off our most critical patients. I got into this business to save lives, and I’ll bet you did, too. Then, somewhere along the way, we became cynical and jaded.

Saving lives makes you believe again. It feels good, too.

For those who want to give the patient the best possible odds of survival, but are severely under-staffed, it is possible to practice High Performance CPR (HP-CPR) with 2 rescuers! Go to the Resuscitation Academy website and click on High Performance CPR – 2 Person!

Further Reading

High Performance CPR: Performance Not Protocol!


  • I think you may be on to something. I would add to your bullet list – immediate hot wash and after action review. Close the loop on the outcome of your efforts.

    Today we have the technology and generally the downtime to take 5 minutes and debrief with the responders on the what worked and what needs attention. Further, a case review of the data and a closeout document for others to review (in a peer review manner)

    Systems of care improve with shared data and involvement of otherwise silo disciplines – 911, Law Enforcement etc. Our agency does not do all of these things YET…improvement is a path not a destination.

  • Thanks for sharing your insight, Joseph! You guys do an amazing job in Wake County EMS and we modeled much of our process from your approach to sudden cardiac arrest.

  • Skip Kirkwood says:

    Just to benchmark – How may people do they send to a cardiac arrest in a hospital?  Where the equipment is all there and the patient, if resuscitated, does not need to be moved immediately upon resuscitation.  ANS:  8-10, or even more.

    Why should we give the patient any less in the hospital?

    And to those who talk about "encouraging" things that don't matter – show us the evidence!

  • Excellent point, Skip. Our job is even harder than in the resuscitation bay in the emergency department. Inside or outside the hospital, it's not just about the number of people, but how they work together as a team.

  • Adam says:

    Im a "new" medic and I work for a Fire Department where we have 3 engines 1 Truck and 2 Medic Units as well as an Assisstant EMS Supervisor. On our Code calls we get the normal EMS Run Dispatch. An Engine/Truck and a Medic Unit. Since I have been cleared as a medic (Less than 5 Months) I have had 2 codes when I am the only Medic on scene and both patients were in VF (witnessed) and both were called at the hospital. When our Asst. Supervisor is on shift he will respond to the Code call as well. I have also been a code where I was on the Engine Crew and we got a pulse back and last that I knew the patient was still alive. It helps having 2 medics on scene and all the help we can get.

    One thing I have also learned is that when you take your time on scene with these patients the outcome is usually favorable for the patient. I have been told my my Supervisors that it's better to stay and play on code patients than it is to grab and go because there is nothing that the hospital is going to do that we can't do. It won't do any good for our patient to be thrown around in the back of the ambulance because we can't do what we need to do in that case.

  • Adam, one of the most important changes EMS systems should initially make when attempting to improve survival from sudden cardiac arrest is to work the cardiac arrest on scene. Your supervisors have that exactly right.

  • Dave says:

    Well articulated!

  • Medic7 says:

    I'm a bit confused as to what is being said in this article.  

    "I think there are several reasons for this. In the first place, most jurisdictions don't have the resources, or at least say they don't have the resources, to do what we we do. But I think the real issue is that people don't understand the benefit of sending 9 to 11 people to a sudden cardiac arrest. In fact, some have argued that sending that many people only encourages therapies (like drugs and tracheal intubation) that have not been proven to positively effect neurologically intact survival.  I disagree. The two issues are not related."  

    What's the point of this opening paragraph?

    "First, we need to consider that sudden cardiac arrest, particularly witnessed VF arrest, is a survivable event — when a process is in place to save that life. Although I don't take credit for the maxim, I have said many times that "every system is perfectly designed to achieve the results that it gets" and I certainly believe that. If the planets need to be in perfect alignment for a patient to survive in your system then it is not geared to save lives. Rather, it is geared to take patients to the hospital and generate revenue."

    What???  You're losing me here.  

    "If the planets need to be in perfet alignment for a patient to survive in your system then it is not geared to save lives. Rather, it is geared to take patients to the hospital and generate revenue."

    What's the connection between "not saving lives" and "generating revenue"? 

    "You might deliver excellent customer service, and you might have talented EMTs and paramedics, but no individual can save lives in a vacuum, or at least, very rarely can they manage to do that."  

    What does "saving lives in a vacuum" have to do with anything, much less the remainder of the article?  

    "Almost every young, highly intelligent, and motivated paramedic who becomes disillusioned with his or her EMS system is told, "just do the best you can in the back of your ambulance and make a difference with each and every patient you come into contact with." You can try to do that, it's true. I'll even concede that you can find some value or solice in doing that."  

    I'm completely lost at this point, and have stopped reading the article.  It's difficult to determine what the point of an article is with based on what I've read thus far.  The title of the article grabbed me, but with poorly associated paragraphs and loosely-connected points, it wasn't difficult for me to become completely lost after the first paragraph. The syntax was entirely inappropriate, and it's poorly constructed from a grammatical standpoint.

  • Stephen says:

    Tom, do you have any data or literature to support your premise? You've only quoted anecdotal "best practices" which feels dangerous in a time when we should be encouraging arguments based on evidence and rational science. My counter would be that perhaps additional manpower is positive and sounds reasonable, but does it necessarily have to be high level fire officer supervision, fire engines, and multiple ALS providers? Also in an era of technology and mobile computing, the medical decision-making can be controlled remotely in-real time by physicians (there is some experimentation with this already in play utilizing Google glass).

  • James Orsino says:

    So Dr. Meyers attributed the Wake County EMS cardiac arrest rate to several other reasons in an article last month. None of what is being used here to claim success was in the Meyers article and none of that in the Meyers article mentioned here. Looks like two guys spending the same $20 to satisfy different tabs.

  • Gina says:

    Good thing this isn't an English class. I think the rest of us got your point, and I thank you for sharing your experience with us. 

  • Stephen says:

    As mentioned by other posters, the trend in the literature is not really to support this type of response. For instance, out-of-hospital cardiac arrests in the early days were primarily attributed to VF/VT now replaced by asystole. Recent research indicates treatable arrests are in much decline and the reductionist approach in CPR/ACLS doesn't bode well with this article. Effective CPR & Early Defib followed by appropriate treatment for correctable pathology is the true best practice. I'd rather deploy telemedicine technology and have medical control supervise the code with an on scene medic collaborating. The rest of the code doesn't necessitate the type of response you are supporting, however I'm glad it seems to work for your community and citizens.

  • J. Myer FF/EMTB (13 years), Paramedic Student says:

    Well I guess nothing becomes a good educational tool if it is not challenged and reviewed. First Tom great article and great points. To those that want statistical data about having more well organized and well trained people on a scene increases the chance for a positive outcome, I say look to  the days of old. as recent as 2001 and 2002 many locations, including a place I was at in northern California, sent A ambulance to a possible cardiac arrest. A Ambulance could call for A engine, which depending on location maybe a local paid department with 2 fulltime people on it, a state engine with a fulltime trained staffing of 4 or 5 people on it, or a volunteer squad which might show up with 2 people that had the day off from work. Point being odds are most of the time you might get to work a code with 4 or 5 people maybe,  but it could be jsut you…all alone. And we had a lot of that outcome in the end back then also. I remember very few actual saves I got to be a part of back toward my rookie days.  Some places, like where I work now, have added the operations supervisor, and the engine on the initial dispatch. So we have all six people headiung there right from the jump. maybe eventually we might become a system that sends an additional engine or medic unit to a code.  The rural town I live in they send 2 of the three fulltime staffed ALS ambulances and the Operations supervisor to every cardiac arrest. And I would say we recognize and save a LOT more people now then we did before. 

    And that is the statistic you should be most impressed by. The number at the end of the week that are able to leave the hospital with some form of quality of life.  We are looking at other things that can be done also to further the process with  out having to send more people. Especially since we are a 3 engine, 2 truck, 5 ALS medic units, a battalion chief and a Operations Captain per shift department. taking a second engien to the call may be a option in the future, and reasonably it possibly could be looked at right now , but that is leaving 3 districts coved by a single engine.  If anything I would like to see some sort of research done to try to disaprove of this type of operation. It is proven that if you throw enough people at a structure fire, building collapse, water rescue, hazmat etc….the desired outcome is quite often reaced faster. With a reasonable limit to homw many people can fit in the living room to perform tag your doing compressions, why would Full codes, STEMIs, and other, major life threaten medical events prosper from the same effect. 


    Thanks again for the article tom great info. 

  • Mick Mayers says:

    I don't normally show up here in the comments section, but I found some of the comments intriguing and wanted to share.  I happen to be one of those battalion chiefs Capt. Bouthillet is referring to. My first EMT cert was in 1982 and my paramedic in 1987.  Pretty sure some of you weren't alive at the time.

    I gave you that information not as if I am some expert in the field, but rather, to illustrate to you that I am not.  Like I said, I have been doing this job for a very long time and frankly, I am considered a pretty good paramedic.  But this also isn't some means of pointing out my expertise.  In fact, it too has contributed to my own befuddlement.

    There are a few of you who are more worried about Tom's writing style than you are about the point being made in the article. Personally, I have pretty strong language for trolls, but this isn't my blogsite, so I'll be polite.  The point of Tom's blog, as well as my "bragging" on my credentials is this: Our organization is saving a considerable number of patients with an entirely new approach to our service delivery.  And I was against it.

    I was not against it, as in agitating against it.  Instead, on a boardwalk in one of our residential communities, the "perfect alignment" occurred: witnessed arrest, bystander CPR, early defibrillation, quality CPR, avoiding treatments that provide questionable outcomes, and excellent, excellent teamwork.  It was before we formally began to deliver our Pit Crew concept, but we happened to have some events that precipitated a call for the extra resources, and I happened to be at a nearby station and responded as well.

    One call does not a scientific observation make.  Prior to this incident, Tom and I discussed the desired increase in response assets on a number of occasions, and I was supportively skeptical.  He had all the right points to show us the idea worked but I cautioned him on timing and approach.  On this alarm, however, I opted to listen and learn instead of allowing ego and "experience" to rule, which probably should be a lesson more people take personally.

    The changes that our department made to facilitate this approach were outside of our normal line of thinking, but we began to have regular payoff.  That patient I spoke of lived.  I remarked after the third one we saved, I think it was, that we had saved more people at that time than we had saved in maybe five or six years total.  Others saw the same results and it caught fire.  If you follow my own blog, you'll note that I constantly urge people to think critically and to consider what you are experiencing versus what it is that is occuring.  The numbers aren't lying and our improvements keep coming.  We continue to have our challenges, but the beauty in the approach is the continued adjustment of the plan.  Continual improvement: wow, what a concept.

    The "high level" supervision isn't because of ay other reason than to provide consistency.  However, if you'd send a battalion chief on a fire incident with a life in danger, why wouldn't you send similar resources to this type of incident? In fact, if you know that all of these conditions exist on scenes (and we all know they do) and you continue to send the same resources "because that's the way we do things", that's just ignoring the obvious: if you need more resources to accomplish the objectives in a given period, then get the resources you need and create success.  If I were asking you to build a shed in an hour and you would be rewarded considerably with a successful outcome, would you charge along bullheadedly with the four people you have, or would you call for more help and get it done?  The reward in this case is that by making sure the resources are present and adequate to manage this incident. the incident outcome has had more success than in the previous model, if the same criteria: the Utstein template, were applied.

    So I'm going to leave it at this. I can't stand trolls. If you want to poke holes in someone's discussion over their syntax, I'm sure you'll have a field day with mine.  Here's the REALITY: We theorized there was a way to provide a better outcome; as a team we built a plan; we exercised the plan; we allocated resources and measured our outcomes. And we found that the plan works.

    This isn't a defense of Tom (he is far more capable than me to defend this premise) or our system (they seem to do fine without me butting in), but an observation from someone who has seen considerable changes in the delivery of medical care in this nation through his own career. Critical thinking involves the civil discussion of arguments to determine their accuracy.  Just because someone is doing something that rubs you the wrong way doesn't mean it is wrong.  And as a leader, I have learned that sometimes it would be better if more people would listen rather than having their two cents over every issue. 

    Read the article and if you have questions, ask them, or suggestions, suggest them. But to those of you who just want to throw rocks, grow up.


  • Brooks Walsh says:

    While EMS has to contend with a number of challenges in the prehospital arena (e.g. poor lighting, crowd control, toxic levels of cat hair), there are some unique barriers to effective resuscitation in-hospital as well. I daresay neither environment is easier than the other.

     – In-hospital, resucitation teams are often formed ad hoc, composed of staff members who perhaps have worked only infrequently together. In the field, you know your partner, and likely the rest of the team as well.
    – Experience and training in the hospital can be variable, with many RNs, even in the ED, having less experience and comfort with active resuscitation than most EMT-Bs.
    – Equipment is often scattered around the floor (if the code is upstairs), and occasionally difficult to find (While the code-cart *usually* has most items, we are discouraged from "breaking the seal" to get acquainted with the set-up). While EMS has fewer resources, they generally know exactly what they have, and where it is.
    – Communication can be difficult in the hospital as well, since codes tend to attract crowds. In the field, roles tend to be clearer, and the scene tends to be quieter as everyone knows what there job is.

    So, while EMS doesn't have it easy, I often am nostalgic for the simpler environment in the field.

  • OAK MEDIC says:

    You only need 3 to 4 people to run a code efficiently. If you have an auto pulse or Lucas device you only need two in reality. Either an EMT and medic or two medics. Otherwise there’s to many chefs in the kitchen.

  • deezy says:

    Oak Medic thank you for backing up your statements with facts/references/science.

    You are the problem, or rather, this is the problem.


  • Stephen says:

    Chief Mayers- I think from an objective point of view we need some valid data over small sample sizes and anecdote.What metrics were used to identify this is an optimal strategy? If none, If you have years of data using a smaller approach and now have amassed years of data using this new approach, it sounds like the beginnings of a quality paper which could be submitted for peer review to soundly argue for increasing responders to OOH cardiac arrests. For now it feels like a hypothesis in need of a conclusion and EMS has suffered far too many emotional and anecdotal drives towards improvement; we should strive for defensible evidence to support our progress. In rank & seniority-based systems such as fire departments this becomes particularly dangerous as senior officers create and promote agendas based on the weight of their authority but lacking the vindication of scientific method. Perhaps your system work fantastically; If so let's prove it so it can be promoted properly and we can improve the health of our communities.

    • Brian says:

      I liked your article and found it very insightful, as well as your BC’s response. As a writer in my freetime, I didn’t see any problems with the language of either post. I think haters just gonna hate.

  • There's very little evidence to guide us when it comes to resuscitation. The AHA ECC Guidelines are great but they only tell you what they think works. It's not a guide book that shows you how to do it.

    That means that you are left in the position of identifying best practices. We chose to do that by interacting with EMS systems with documented success with resuscitation.

    You shouldn't take any advice from anyone who isn't doing better than you are. So, for all of you who criticize the way we do it, why don't you tell us your affiliation and what your survival rate is so we can judge your credibility?

    We belong to the CARES registry and we measure our performance. This process works well for us, which is why I'm sharing it with all of you. Your mileage may vary.

    P.S. I don't really care if anyone likes my writing style. That's why web browsers have the [X] in the upper right hand corner.

  • Barbara says:

    I have almost 30 years as an ED RN.  The progress that has been made in my career is amazing. I have the utmost respect for our EMS and what they accomplish in the pre-hospital setting.  We receive everything from large well organised depts to outlying volunteer depts who have 2-3 EMTs in their farm clothes.  In those circumstances  treatment needs to be determined by resouces/knowledge/protocols of the individual units. Pit Crew is not  one-size fits all.   

    . I do want to extend kudos to the author and his dept for thinking out of the box to find what works in their size dept to better provide care and improve outcomes. This could give food for thought to others and promote evaluation of existing models   After all, any process change that can save lives is a good thing..That's what we're all here for. 

  • Mick Montoya says:

    A Great article, I appreciate the time and effort put into this. I would like to weigh in with an alternate point of view. I work in a paid/volunteer department in a rural community, our overall manpower is limited and transport times are long. We are taught that on any call of high priority it is ok to call in an abundance of support and as the event evolves, resources can be scaled down or cancelled as needed. On a cardiac arrest, I would rather know that I have help and then some on the way if things go from bad to worse. Those who do the small things like scribe and are runners to the truck for extra gear are just as vital as the ones stuck in doing chest compressions or the like. From a customer service level, the loved ones watching you work and seeing an overwhelming response to help their loved one is a visual indicator that we are doing everything we can and when you are professional in your work, it means everything to those who witness us. Even if I have a couple of people standing in a door way, waiting for something to do, I know that they are ready and I can use them when I need them to. I don't know what unforseen problems might erupt and need those extra warm bodies on a critical event, caridac arrest or what ever the emergency might be. What we should be remembering on every call is to prepare for the worst and hope for the best. So what if you have guys "on the bench"  waiting for a task? If it comes down to it they can be released or split off to another call if it makes sense.  Do we always have 9-12 at a cardiac arrest? No, but there are times I wish I did.

  • Stephen says:

    Tom, it isn't a matter of judging any one person's credibility nor is it a personal attack. I applaud bringing a valid hypothesis to the table and enjoyed the article, however we all need to encourage empirical data, not best practices or expert opinion, to allow our claims to stand. I'm certainly glad you have seen improved results in your system. Would you mind to share actual data with us in support of your argument? 

  • Alan says:

    I'm sorry but the figures speak for themselves, you saved three in a row and that is more than you have saved in five or six years?? that Gentleman, is not statistics, it is coincidence,

    This don't forget, is America, you send the response you can afford to send and still remain profitable, the amount of resources availble on any call is a function of how much you are able to charge for that call, and not one of any clinical based need…..



  • Cascade Medic says:

    I am sure that Tom and his department don't need me to defend them. I do not remember where but I believe their resuscitation rate may be north of 50 % for witnessed VF, Tom could comment on this. I think what I see from Toms and his BC's comments are what the Resuscitation Academy teaches is the absolute hardest thing to achieve in your department and that is a Culture of Excellence. The belief by all personnel (from dispatchers to fire inspectors) that witnessed VF is a survivable event. People who are willing to drop what they are doing if they are close, regardless of rank, and attempt to provide early HP CPR. To walk in the door with a backboard because the default position is this person survives this event and we don't take dead people. I hope one day my own department can achieve this level of cultural excellence but it will take time.

    The main call it seems in the thread is to provide some science to back up a large manpower commitment.  When we returned from Seattle's class we were also met with some of the same skepticism. Our first request was to increase cardiac arrest call response from 5 people to 8 including a BC. This was met with a less than an enthusiastic response from the OPS chief. For our small city this would equate to a 60 % commitment of on duty resources.  As Tom pointed out we also happily send 90% to a smoking pot on the stove but that point fell on deaf ears.

    The point that should hit home and the one we used is rescuer fatigue.

    Rescuer fatigue under 2010 ERC guidelines and its effect on CPR performance Emerg Med J. 2013 Aug;30(8):623-7


    This study looked at 62 students who were asked to perform 5 minutes CPR on a recording skills manikin and the students were asked to report their fatigue level. We add in Hawthorne effect to this and yet the outcomes still show a steady decline in correct depth.  79 % of the students reported fatigue at an average of 167s.

    The proportion of chest compressions delivered correctly decreased from 52% in min 1 to 39% in min 5, approaching significance (p=0.071). A significant decline in chest compressions reaching the recommended depth occurred between the first (53%) and fifth (38%) min (p=0.012). Almost half this decline (6%) was between the first and second minutes of CPR. Neither chest compression rate, nor rescue breath volume, were affected by rescuer fatigue.

    Our own data from the monitors appeared to corroborate this. We found rescuers asked to 2-5 rotations on the chest with as little as 2 minutes off were having increasing depth of compressions problems and we suspected complete release issues. (We have no way to measure this currently) Indecently I have never heard a firefighter report fatigue during CPR.


    Fatigue affects chest compression delivery within the second minute of CPR under the 2010 ERC guidelines, and is poorly judged by rescuers. Rescuers should, therefore, be encouraged to interchange after 2 min of CPR delivery. Team leaders should be advised to not rely on rescuers to self-report fatigue, and should, instead, monitor for its effects.

    What we do not know is how long of a rest period is required to maintain 2 minutes of proficient CPR.  This study needs to be done and would be a nice segway into pinning down how many people are needed to maintain perfect cpr for up to a hour.

    Fatigued rescuers are a big issue because if you are not doing adequate depth of compressions you are failing your patient.

    What is the role of chest compression depth during out of hospital cardiac arrest?Crit Care Med. 2012 Apr;40(4):1192-8


    We studied emergency medical services treated out-of-hospital cardiac arrest patients from the Resuscitation Outcomes Consortium Epistry-Cardiac Arrest for whom electronic cardiopulmonary resuscitation compression depth data were available, from May 2006 to June 2009.

    They looked at 1029 patients from 7 ROC sites in US and Canada.


    We found suboptimal compression depth in half of patients by 2005 guideline standards and almost all by 2010 standards as well as an inverse association between compression depth and rate. We found a strong association between survival outcomes and increased compression depth but no clear evidence to support or refute the 2010 recommendations of >50 mm. Although compression depth is an important component of cardiopulmonary resuscitation and should be measured routinely, the most effective depth is currently unknown.

    Although the authors note that ideal depth is currently unknown, deeper, up to 50 mm, appears to be better. We can see this in results graphs provided.


    Luckily for my math challenged brain Dr Slovis did the math for me in his PowerPoint”5 most important EMS articles of 2013" in Texas this year. (He also talks about the former study)


    If compression 1.5-2.0 inches:

    Rosc improved  24 %

    1 day survival improved 52 %

    Survival to discharge improved by 91 %

    Tie that study with incomplete recoil because you’re tired:

    Effects of incomplete chest wall decompression during cardiopulmonary resuscitation on coronary and cerebral perfusion pressures in a porcine model of cardiac arrest.  Resuscitation. 2005 Mar;64(3):363-72



    Nine pigs in ventricular fibrillation (VF) for 6 min, were treated with an automated compression/decompression device with a compression rate of 100 min(-1), a depth of 25% of the anterior-posterior diameter, and a compression to ventilation ratio of 15:2 with 100% decompression (standard CPR) for 3 min. Compression was then reduced to 75% of complete decompression for 1 min of CPR and then restored for another 1 min of CPR to 100% full decompression. Coronary perfusion pressure (CPP) was calculated as the diastolic (aortic (Ao)-right atrial (RA) pressure). Cerebral perfusion pressure (CerPP) was calculated multiple ways: (1) the positive area (in mmHg s) between aortic pressure and intracranial pressure (ICP) waveforms, (2) the coincident difference in systolic and diastolic aortic and intracranial pressures (mmHg), and (3) CerPP = MAP–ICP. ANOVA was used for statistical analysis and all values were expressed as mean +/- S.E.M.

    So 100%-75%-100% each for a minute and they measured coronary and cerebral perfusion pressures. The results show some interesting outcomes.


    With CPR performed with 100%-75%-100% of complete chest wall recoil, respectively, the CPP was 23.3 +/- 1.9, 15.1 +/- 1.6, 16.6 +/- 1.9, p = 0.003

    So coronary perfusion pressure was good then dropped and surprisingly did not recover with 100 % CPR again. We see similar results in the brain.

    The striking observation [was] that there was little or no immediate recovery of coronary and cerebral perfusion pressures after returning to 100 % decompression.

     [This] further demonstrates how important complete chest recoil is for effective CPR and how, even 1 minute of improper chest wall expansion, negatively influences these… variables.”- Yannopoulos et al.

    (Sorry don't have a link to quote this came from RA slides)


    This science was enough to sway our operations to increase response to these incidents.  We will close out year 2 of monitoring of survival Dec 31 this year.


    “Measure improve, measure, improve…” Dr Mickey Eisenberg MD PhD Medical Director King County EMS

    As Tom pointed out in his response what is your community's cardiac arrest survival rate? If you cannot rattle that number off then that is the starting point for improving survival in your community.


    Most important you are only as strong as the weakest link in the chain of survival.


    A final link to a great guide to improving survival from the RA.




  • Simon says:

    I am a student paramedic in Australia in my final year of university, and despite limited clinical experience, agree with the author. I think it is unhealthy to resource jobs according to "success/failure" data and statistics – we also claim our service is grossly underfunded and under-resourced. I went to a (witnessed) arrest which was attended by two crews (both with a student), an intensive care paramedic, HEMS flight paramedic, technician and pilot, and a team leader (i guess because so many resources were in the one place). All 11 of us had a job, were helping each other, offering different opinions, checking each others interpretation of the ECG and data, periodically rotating CPR duties to minimise fatigue and maximise effectiveness, and importantly maintaining communication with the family – one big multidisciplinary team with varying skillsets, working effectively, in a tiny room. With everything seemingly considered, there is a noticible calmness to the crew and a lot more smaller details are discussed (compared with arrests i have been to with a crews of 2 or 3 which seem under-resourced). Unfortunately, the patient died, but we know we undertook best practice, spared no resources and gave that patient every possible chance of survival. The family's welfare then became the priority of the job, and i hope they remember us for doing everything we possibly could, and trust their awful journey ahead was a little less burdensome knowing this. I would want not want one scrap less in resources or effort if I was either the patient or the family in that situation.

    • Ben Waller says:

      I am also a Battalion Chief in Tom’s system.
      In addition to the AHA bullets he mentioned regarding high-quality CPR, our response is designed to provide fatigue-free CPR by sending enough people so that no one does CPR for more than 2 consecutive minutes.

      As for science, we believe strongly in it, but we also believe in developing best practices based on it. Science isn’t going to write your dispatch SOGs or tour Pit Crew CPR protocols for you.

  • Greg Friese says:

    Well done Tom. Any change can quickly become "that's the way we do things." Continually analyzing the processes and outcomes creates a dynamic and effective organization. For many of us the esprit de corps is an important reason for our involvement. What better way to realize esprit de corps than to train and respond together. 

  • Stephen says:

    Unfortunately we have limited resources and we must use science to determine the best possible allocation of what we have to maximize the lives we can save. To the poster who quoted several literature articles, you made a fantastic case for high-quality CPR. This is an absolute must. But this doesn't necessitate the leap in logic to conclude that the ONLY personel that can provide high-quality CPR ride on fire apparatus with hoses, ladders, 500 gallon water tanks, battallion chiefs, salaries, and pensions. Are professional rescuers a must? Certainly. Is dispatching the same resources designed to keep a city block from conflagrating needed to respond to a single downed individual? We DO need to rethink the culture; perhaps fire has perfected the art of quick professional response in the neighborhoods, but that doesn't mean pumping millions in cash into sending additional fireman and responders to a scene.  Remember, the majority of the success of OOH cardiac arrest depends on what the lay rescuer does; this is just as essential as the other links in the chain. Yet nowhere we find evidence that justifies what this articles supposes. Great discussion; we can all work together to share ideas and improve the state of emergency care in our communities.

  • Cascade Medic says:

    Stephen, I agree that firefighters, paramedics, EMT's are not the only ones that could be trained in HP CPR. We currently have expanded the training to our local police department and to federal firefighters (USFS and BLM).  We are monitoring closely how well they do compressions (AED data) and watching for skills degradations over time. The literature cannot seem to answer how often we must recert to maintain skills. In house, even 2 times a year on recording manikins is hard to schedule around other things. For police and outside agencies I think the time and fiscal commitment are a tough sell. "Not really in my job description" can be the attitude. Leveraging current assets in our communities is a paramount, I agree. How to keep others not tasked with medical response up to speed is vexing and costly. I welcome any ideas other communities have tried with success. Lay rescuer response as you pointed out is a key to success. I don't think you can have a really successful system without a robust community response. This can be tough link to improve and takes partnerships and time.  An aggressive telephone CPR system helps get that critical intervention started early but does negate the need for bystandard response. Hopefully we will see Hands Only CPR be the standard of public training by 2015. I hope this translates into more willingness for the public to start CPR and not say "I did my public duty, I called 911."  Programs like Pulse Point may also help with lay rescuer response and bear tracking for efficacy. I think the science does need to look at numbers of responders vs. survival. I am very far from an expert in experimental design but a retrospective study of ROC sites might give us a starting point. Something like number of responders on scene tied to outcome data; ROSC, 1 day survival, CPC score, 6 month survival. I don’t know if you could control for all the variables (perhaps someone with a statistics background could comment). Thanks, enjoy the discussion. Happy holidays.

  • James Orsino,

    Wake County has an amazing working relationship with their area fire departments, who contribute resources to every cardiac arrest they work. They send roughly as many folks to a call as Tom's department does. An integral part of their save rates is quality CPR, without which the remainder of the system is not going to affect much change.

    Your choice in systems is actually a great example of why the approach outlined in this article works, and works well.

    I encourage you to come out to NC sometime and ride with one of our high performing systems (Wake, MEDIC, New Hanover, BrunsCo, HendersonCo, and countless others I know I'm leaving out). We may change your mind on resuscitation (or we may not).

  • Ben Waller says:

    Oak Medic…

    The goal isn’t to run the code efficiently, it is to run the code effectively so that the patients go home and hug their families.

    I work in the same system as Tom. Our patients survive at much higher rates than before we changed our approach. Sending enough providers to provide fatigue-free compressions is one of the things that contributes.

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