This post is inspired by a book I am reading Ė Antifragile: Things That Gain from Disorder by Nassim Nicholas Taleb. In this fascinating book Taleb discusses risk. Take this example which I am modifying from his book:
Would you get on an airplane if there was only a 5 percent chance that the plane would crash?
While the odds may be in your favor that you will likely not crash, the outcome of those small odds is so catastrophic that you would be a fool to board the plane absent astonishing circumstances requiring your seat on the plane (to save a loved one, to prevent a war from starting, to collect a trillion dollars). The possible benefit of getting on such a risk prone planeóis insignificant when compared to the possible drawback of crashing Ė losing your life.
Most bets we make, according to Taleb, are asymmetrical. The amount to be gained or lost is not equal. If you are going to bet, you want to bet where the losses are minimal and the payoffs far exceed the downside. Position yourself to avoid catastrophe.
While Taleb talks a lot about economics and other subjects, letís apply this simplified concept to EMS.
ďWhy wasnít a 12-lead done?Ē
ďI didnít think it was cardiac.Ē
So your patient has syncope with a recent history of dehydration. You brought the lady in yesterday after a similar episode, and the ED sent her home after hydrating her. She is 80 and appears ill. You have been a medic for twenty years or perhaps you are a cocky brand new medic. Your gut tells you it is not cardiac. In fact you are 95 percent certain it is not, so you donít bother with a 12-lead…
Your EMS coordinator or training officer pulls you into the office and says your patient in fact had a STEMI and went into cardiac arrest on the way to the cath lab after sitting in a room for 20 minutes until the ED did a 12-lead and spotted the anterior STEMI. If you had spotted the STEMI, the patient would have likely been cathed before going into arrest, and while resuscitated, she likely will have a significantly diminished ejection fraction as a result of the arrest and delay in treatment.
What was the gain from choosing not to do a 12-lead and going with your gut?
You didnít have to exert yourself to do a 12-lead.
What was the worst possible outcome of not doing a 12-lead?
The patient would be having an undiagnosed STEMI and due to the delay in diagnosing her, she could die before she could be reperfused in the cath lab.
Thus the decision to withhold the 12-lead is in Taleb’s view, a fragile one. If you lose, you (and the patient) can be broken. You want always to avoid the state of fragility. You want to be antifragile. Your gut may tell you itís not cardiac, but in this situation where the possibility of failure exists, having a redundant system like a 12-lead provides you protection. At a low cost of doing a 12-lead, you prevent a catastrophe Ė missing a STEMI.
Minor exertion versus a patientís death. The potential gain and the potential loss from the bet that it is not cardiac are not equal. Low upside if you are right, big downside if you are wrong.
Now for those of us who cast a wide net with our 12-leads, this may seem like much ado about nothing. There is no way despite our guts, this patient is not getting a 12-lead, but letís apply this same reasoning to another scenario.
Why did you spend so much time trying to get an ET tube on that lady instead of just popping in a combi-tube?
ďI thought I could get it.Ē
Obese female grabbed at her chest, and went unresponsive five minutes before your arrival. She was fortunate enough to get bystander CPR, but it doesnít look like they are doing it very well. The seconds on her survivability clock are ticking quickly down to zero, unless you can intervene quickly and with great skill.
You put her on the monitor and see she is in a fine v-fib so you shock her X 1 and resume CPR. You want an advanced airway so you can do continuous compressions (instead of 30:2) as well as secure her airway Ė get more oxygen in and more CO2 out. You have two choices Ė an ET tube or a combi-tube.
You choose the ET tube. Why?
Well, it may be a better airway. It is the airway the hospital will use if you get her back and she remains unresponsive (under sedation) whereas if you put in a combi-tube, the hospital will eventually pull it and put in an ET. Also, you like intubating. It is a paramedic skill and one you donít get to do as often as youíd like so you donít want to pass up on the opportunity. Plus, when you talk about the call later, everyone will ask if you got the tube. If you are a new medic people want to know these things, and you want to show them you are worthy of the rocker on your shoulder. If you are a 20-year medic people will expect you to get it.
And most important of all Ė you think you can get it. You think there is perhaps an 85% chance you will get it, or maybe scale that down to 75% as you do notice, she has a thick short neck and protruding teeth. Still, you think the odds are in your favor. You go for it!
So what are the risks and benefits?
If you get the tube quickly you are a stud and the ED wonít have to switch out tubes as long as your crew doesnít yank it. If you can do it without much interruption in CPR, all the better. Now the studies do show that ET attempts cause many interruptions of CPR, and you know that is true, but not in all cases, and sometimes you do intubate flawlessly and with great skill. No interruptions in CPR Ė even when checking lungs sounds. You can do it!
Now how about the risks?
If you donít get the tube flawlessly, there could be problems. You will look bad for trying three times and not getting the tube. But wait a minute, we are not really concerned with you, we are concerned with the patient. Thatís who the real risk is too.
If you are a medic working by yourself, it takes longer to get out all your equipment to intubate than it does to rip open and insert a combi-tube. If you canít sink the ET tube on first look, CPR may be interrupted or the patient may not be ventilated well. CPR may be interrupted while you intubate, and your patient who is already on the brink of death may go to the darkness while you dick around trying to get the tube. It may not happen every time, or most times, but some tubes are, shall we say, challenging.
Reward you get the tube. Risk you cost the patients seconds if not minutes that they may not have. An asymmetrical bet. Small upside, big downside if the bet goes wrong.
Given that this patient is likely already on the razor blade edge between imminent tissue death, imminent anoxia and chance of full neurological recovery, I think we have to do everything to obtain immediate airway (oxygenation/ventilation) relief with no delay in compressions.
When seconds count, seconds should count. The risk of the most difficult airway I think is too great in this particular described patient. It is not a 75% versus 95% proposition. It is a possible loss of 10 to 60 seconds when a patient may not have those seconds left.
Wouldnít it be great if every patient we showed up to in cardiac arrest had a visible life clock hanging on the wall above them. 0 seconds remaining, we donít even have to go through the motions. 2 minutes remaining, we can take our time rolling up our sleeves and taking control. Or maybe 20 seconds remaining when we have to act fast and with that great skill. Deliver that jolt. Pound those compressions Ė they must be excellent. Secure that airway.
It doesnít matter how well packaged the patient looks when we bring them into the ED doing CPR. ET tube, 2 IVs, run through the entire ACLS algorithm. It matters if we can get them back before that last grain of sand falls in their life clock.
We might save a human being who would otherwise pass. So what if they have to change out the Combi-tube to an ET tube later. Big upside, low downside.
Now I may be butchering Nasemís points, and his book is certainly more complex and well thought out and argued than my meager post. The point is reading the book has made me look at a situation that I have struggled with in a new way. I donít think I was adequately assessing the risks. When a life is at stake, I should err with whatever is more likely to avoid a catastrophic outcome.