Pre-decisions, Part 2

In the fictional scenario from Part 1, I asked the questions whether the patient should be a STEMI alert and whether she should be transported emergently.  Check the scenario to catch up if you haven’t already done so.

For me, the STEMI alert question is easy – this patient is not a STEMI alert in my EMS system.  An alert requires ST elevation plus cardiac-type symptoms in the absence of exclusion criteria.  This patient had no symptoms whatsoever, so the alert is out of the window.  If the patient was having a posterior MI with ST depression in V1-V3, I couldn’t alert either (there being no ST elevation) – even though I know the patient is having an MI and needs a cath lab.  Remember, however, that the STEMI alert is shorthand communication meant to replace the whole description of a specific type of MI.  Nothing is stopping me from describing another type of MI - saying something like, “Prepare for an MI.  This isn’t a cardiac alert because X criteria is missing, but I am positive that this is an MI…” Usually, the response by the hospital is the same as it would be for a formal alert.

So the bigger question is whether or not to transport the patient in this fictional scenario emergently.  I think it is important to think through your decisions before you are making them under pressure.  At least come up with a framework to help make decisions before you’re under pressure in the middle of a stressful situation.  So let me explain how I do it for emergency transports.  The process is the same for all other decisions – whether to start an IV, what to bring into a call, when to give analgesia, etc.  There are dozens of decisions on every call, and they all need to be pre-decided to some extent.

My first step is to think about the pros and cons (or, if you prefer, the costs and benefits) of the decision.  In the case of emergency transport, the theoretical benefit is that the time to hospital is possibly shorter.  I don’t think it is usually greatly shorter, and the amount of time saved is based on geography, distance to the hospital, traffic patterns, and such.  The subset of patients, even really sick ones, that have a positive effect from getting to the hospital more quickly is pretty narrow, too.  The cost is increased danger (ambulance crashes and wake wrecks), increased roughness (faster is rougher in the back of the bus), and increased patient anxiety (which I think is minimal, but theoretically could exist).  The specific setting you find yourself in will dictate if the benefits outweigh the costs.

Cost.

Next, brainstorm every reason to transport a patient with lights and sirens.  It doesn’t matter whether the reasons are obviously dumb or not.  It is helpful to list them all out, even the blatantly dumb ones.  My complete “reasons to transport emergently” list:

• Obvious threat to life or limb – These people are making a solid attempt at dying in front of you.  This includes cardiac arrest, airway compromise, unmanageable hemorrhage, etc.
• Likely threat to life or limb – These people aren't necessarily circling the drain, but their disease or injury is not especially compatible with long life.  I would include things at the level of gunshot wounds to the torso with normal mental status and vital signs here, along with myocardial infarction and resolved airway issues (post successful intubation), etc.
• Potential threat to life or limb – There is really no obvious threat here, but there could be.  This level includes patients from severe mechanism crashes, for example.
• Possible threat to life or limb – Now we are getting to the theoretical end of the range of life threats.  And I suppose it is possible for a phalanx fracture to release a teeny little fat emboli that ends up in a lung causing a pulmonary embolism, right?
• Time-dependent intervention I can't give – I am thinking of emergent caths and surgical interventions.
• The protocol demands it – My agency’s protocols never say to transport with the lights and siren, but a different set of protocols might.
• Boss expects it – Not just a supervisor, but a Medical Director, a preceptor, or even a partner may have expectations of emergency transport.  Those expectations can influence our transport decisions.
• Send message to hospital/Improve reception – Nobody likes to get ignored for several minutes after arriving to the ED, getting sent to a small back room, and waiting five more minutes to give a nurse a report.  Transporting emergently ensures I get a big room and a lot of attention immediately.
• Send message to quality assurance staff – I want the QA folks to know that I was taking this patient seriously.
• Send message to "lawyers" – I want to avoid getting sued.  So if I transport with the lights and siren, any problems are harder to put onto my shoulders.
• About to get off shift – Listen, we all want to go home on time.  We have lives and things to do.  The daycare center will call the cops and claim that I abandoned my child if I’m not there by 6pm.  I can’t drive this patient to the hospital in the flow of normal traffic.
• Have to poop – If the choice is lights and siren versus going home to shower and change, isn’t the emergency transport warranted?  I’m not talking about a little discomfort – I’m talking about serious issues like diaphoresis, weeping, barely restrained panic, and negotiating with your own body parts. 
• Wang Rule – The ‘Wang Rule’ holds that any traumatic injury to a person’s genitals warrants an emergency transport.  Solidarity [thump your chest with a fist].  If it were my joint that was bleeding, I’d want to hear the siren.
• Bill at higher rate – The financial viability of your agency is important.  Emergency transports are reimbursed for more money.  Doesn’t that make good financial sense?
• To run the next call – Some small EMS systems only have an ambulance or two.  If there is one more emergency call than you have ambulances, does it make sense to transport the earlier call emergently as a part of the emergency response you’re about to go on?

That is a pretty complete list.  Now go through the list and ponder the logic behind each item.  For which do the benefits outweigh the costs?  Is each grounded in good medical care, logical, consistent, legal, and defensible?  If not, mark it off your list.  The result is your pre-decided reasons for transporting emergently.  Some are indefensible - getting off shift on time.  Some are probably illegal - billing at a higher rate.  Some just aren't grounded in logic and science.

For me, the final, defensible list includes obvious life/limb threat, likely life/limb threat, time-dependent intervention, and have to poop.  I would discuss the ability to run another emergency call that was holding, but that doesn’t really come up in my system.

Going back to our original scenario and the emergency question transport, I don’t think that this patient falls into my emergency transport rationale.  Her ECG is certainly abnormal and very concerning, but she has absolutely no complaints and her vital signs are normal.  In addition, this is an issue that has been troubling her for days.  The distance to the PCI facility is short.  I think she has a potential life threat and I would certainly be monitoring her closely.  All of those combine to result in a non-emergency transport for me. 

There are two main points about that last paragraph.  First, doesn’t that sound like a good answer to give if I were called into a boss’ office to explain that decision?  Reasonable, logical, thoughtful.  Nice.  Second, your threshold to differentiate between likely and potential life threats may be different.  Your list of pre-considered reasons for emergency transport may be different.  Your confidence in your abilities may be different.  Your reassessment may indicate that the patient went from potential to likely life threat and the time has come to step it up – you’re not locked into a transport mode.  All of that is okay.

The important point that I am trying to make is that your decisions be thoughtful, reasonable, and considered.  It is hard to consider all of the factors when you are also orchestrating the scene, caring for the patient, and making a to-do list in your head.  As much as possible, do it in advance.  Don’t make decisions based on gut feelings, habit, or what you think other providers in your agency would do.  Think them through.

Pre-decisions, Part 1

Let me run you through a fictional scenario and see what you think.  I hope it will illustrate the best way to preplan decisions in EMS.

You respond to an internal medicine office to find a 56-year old female patient without complaints.  The lady stopped by her doctor’s office because she gets chest pain every day for the last week when she is active – climbing stairs and step aerobics class.  Last night she didn’t sleep well and could not get comfortable, but did not have chest pain.  Her description is that she felt vaguely anxious.  She has a history of mild hypothyroidism for which she takes levothyroxine, but has no allergies.  She is warm, pink, and dry; completely oriented and cooperative; and appears to be in no apparent distress.  As a matter of fact, she seems a bit confused as to what the big deal is.

She has a blood pressure of 132/68, pulse rate of 90 beats per minute, and a respiratory rate of 14 per minute with no respiratory distress and clear breath sounds.  She reports neither recent trauma nor recent illness (other than the recurrent intermittent chest discomfort during exertion).

Her ECG:

Well, that's not good.
(Photo courtesy HavocOneThree, with permission)

This is a sinus rhythm with bigeminal PVCs and normal axis.  The sinus beats show ST elevation in V1-V3, but there is also the possibility of left ventricular hypertrophy* – the ST changes may be due to that, or they may be due to an anteroseptal MI.  The ST changes look a bit aggressive and convex for LVH, to my eye.  There is poor R wave progression, with V1-V3 negative before V4 is predominately upright.

So you press her, ask leading questions, and beg.  But she still will not claim a complaint at all – she states that she feels completely normal and is still not even sure she needs to go to the hospital.

She agrees to be transported, however, and you apply oxygen via nasal cannula, administer 324mg chewable aspirin PO, and establish an IV.  Her repeat vitals are unchanged, and her pulse ox is 100% on 2L.  You are four or five minutes away from a PCI facility.

So here are the questions for discussion:

• Should she be a STEMI alert?
• Should you transport her emergently (lights & sirens)?

After arriving to the hospital, you hand off the patient and the ED staff get a cardiology consult.  It is decided to cath her and see what is going on. 

During the informed consent discussion, the patient refuses the cath.  She states she only has an hour until she has to be home for some family stuff.  As the hospital staff works very hard to convince her to agree to the cath, the patient suffers a VF arrest (about 30-45 minutes after you dropped her off).  She is defibrillated, pulses return, and the emergent cath shows 100% LAD occlusion that is stented.

Does that bit of hindsight change your thoughts on whether she should be a STEMI alert and/or whether to transport her emergently?

I’m interested in your thoughts.  Please share in the comments.

*The simplest way to determine the possibility of LVH is to remember the number 35: Find the deepest S wave in V1 or V2 and measure the depth.  Find the tallest R wave in V5 or V6 and measure the height.  If the number is greater than 35mm, you have a positive finding.  Add to that whether there is a lateral strain pattern.  The final part is whether or not aVL is greater than 12mm tall.  In this case, V2 is 27mm deep plus V5 is 16mm tall – 43mm.  There is a strain or strain-equivalent pattern of the ST and T wave in the low lateral leads.  But aVL is small – so there is only a fairly strong possibility of LVH here, not guaranteed.

Habits

A new year is a time for resolutions, which are essentially an exercise in either changing old habits or making new habits.  Coincidently, I just finished reading The Power of Habit: Why We Do What We Do in Life and Business by Charles Duhigg (NY: Random House, 2012)* and it got me to thinking about the habits that I have on the job.  I don’t think that I spent enough time at the beginning of my career thinking about establishing good habits.  That’s not to say that most of my habits are bad, just that some of them may be… suboptimal.

Some habits are more productive than others.
(Carlos Paes, Wikimedia Commons)

According to Duhigg, personal-level habits are the brain’s shortcuts to perform common, repetitive tasks.  It begins with a cue, the habit kicks in, and a reward comes at the end.  By using habits to perform common tasks, like starting the car, our brain is freed to think about other things.  You don’t have to consciously think about getting your keys out of your pocket, unlocking the door, sitting down, putting the keys in the ignition, and all of the other steps in order.  It is an incredible evolutionary development to be able to think about your to-do list for the day while all of those other actions are going on. 

If the habit is a positive one, that is.

Think about the habits that you have when you are working.  You probably don’t realize how many of your actions are habitual:

• How you belt a patient onto the bed
• What you do right after you get a call
• What you do right after you decide to start an IV line
• How you approach a patient
• Your personal introduction and first few questions to a patient
• How you take vital signs
• How you give a verbal report
• Your initial actions when you walk up to a car crash
• How you check out your ambulance before a shift
• How you clean up your ambulance before a shift

There are dozens more.

What do you do when you get a call?  You put whatever you’re doing down, I assume, but do you put it away, or just toss it behind your seat?  Why? Do you look up the location on a map?  Why or why not?  When do you put gloves on?  Why then?

What objects do you grab when you need to start an IV?  Why do you choose those?  Do you toss them next to you or do you lay them out in a specific way?  Why?  Do you tear your tape beforehand or leave it on the roll?  Why?  What locations do you check first on a patient?  Which arm do you rope off?  Why?  How do you position your body?

How many of your habits were created through the thoughtful consideration of “I want to make this a habit”?  Can you explain what you are trying to accomplish and why?  If not, shouldn’t you reconsider your habits and whether there are more optimal ways to accomplish those tasks? 

For me, there are a few habits that I have thoughtfully established.  For example, I belt patients onto the bed the same way each time.  My habit is to pull the axial straps high up into the patient’s armpits and place the leg straps immediately above the patient’s knees.  I make sure the straps are snug without being tight, and I flip the buckle over so that the release button is down.  I do that on every patient because I don’t always know which ones will become unexpectedly violent enroute to the hospital.  It is easier to just habitually place the belts correctly, rather than to struggle to rearrange the belts after everything has gone pear shaped. 

Other habits have been incredibly hard to change.  I would love to make it a habit to listen to breath sounds after each blood pressure.  I could just move the stethoscope from the patient’s arm to their chest.  Instead, I have to make a choice to listen to breath sounds.  I keep working at it, though. 

Another example: I wish that I learned to start IVs left-handed.  Think about the orientation of the patient’s arm when they are lying on the bed in relation to your hands when you are sitting next to them on the ambulance bench.  Your left hand offers a straighter line to start an IV without excessively abducting the patient’s shoulder.  To comfortably start an IV with your right hand on the patient’s left arm, it is easiest to bring the patient’s arm to a spot that is almost perpendicular to the rest of their body.  My left hand has a straighter line. 

That’s it.  I’m gonna start all lines with my left hand in January.

Establishing good habits is a primary task when you are training, but you may not realize it.  Many of the habits that I have are the result of my first preceptors, trainers, and partners.  It is an important responsibility, and I wish we more clearly understood that that is what we are doing.  Trainers insist that trainees perform tasks in a certain way – the way that a secondary exam is performed, for example.  By repeating that lesson, a habit is established that will probably follow that trainee for the rest of their career.  If you are training, I hope that you are establishing sensible habits in your trainees. 

Now that most of you are established providers, challenge yourself to think about which habits you have, critically examine them, ask yourself why you are doing them, and change them if there is a better (more logical, more intellectual, more efficient) way to do the task.  Don’t be a slave to your habits.  Change what needs to be changed. 

A new year is a perfect time to start that process.

* I would recommend reading this book.  It is a pretty good read, in that it got me to thinking about this topic, but it also strikes me as a little bit shallow in its examination of the topic of habits.  It reminds me of superficial pop-psychology books like those written by Malcolm Gladwell.  I’m sure the details go much deeper and the case studies used to illustrate points are much more complex, but it is a fine book to spend some time with.  But I like Gladwell books (Blink and Outliers especially) because they make me think, too.

Wide Complex Tachycardias

You are dispatched to the report of a sick case.  Upon arrival, you find a 52-year old male patient complaining of palpitations.  When pressed, he complains of very mild chest discomfort that he refuses to describe as “pain,” but is worth a two on the 0-10 scale. He has an irregular pulse rate of 130, a blood pressure of 116/70, and a respiratory rate of 16.  He is warm, pink, and dry and is completely awake and oriented with humor.

His ECG:

I started this post expecting to clear up misconceptions about the differentiation of wide complex tachycardias (WCTs).  I wanted to explain some of the main differentiation algorhythms with their reported sensitivity and specificity.  I was going to include algorhythms from Brugada (1), the American College of Cardiology (2), Verecki (3), and Griffith (4).  I’ve taught 12-lead ECG interpretation for more than 10 years, so this kind of topic is right in my wheelhouse.

I decided not to waste my time or your time.  The lesson is simpler than that: Prehospital and emergency differentiation of WCT is a waste of your time.

There are several issues with the differentiation of WCTs.  First, all of the algorhythms have low specificity.  Specificity is the percentage of cases that are negative for the condition and are found to be negative after applying the test – the true negative rate.  So, low specificity means that the test “pings” when the condition isn’t there.  Think of a radar detector in your windshield that alerts constantly, even when there is no speed trap.  Even the relatively higher sensitivity (true positive) ratings of the WCT algorhythms are only in the high 80% range.  That means you will get a false positive (read: be on the wrong path) about 10% of the time.

The second issue is that the algorhythms are complex - probably too complex for prehospital use, especially in front of a patient who needs your time and full attention.  For example, the ACC algorhythm has four main decisions, plus 13 morphology clues to remember.  How often will you practice using that?  A sub-point of this one is that most of the differentiation algorhythms involve precise measurements of R-wave to peak times, nadirs, and V_i/V_t ratios* that are difficult to measure accurately.

The third reason not to differentiate in the field is that there is no upside.  Every decision you make has a cost-benefit analysis, whether you overtly weigh the two sides or not.  The cost side doesn’t matter in this case because there is no upside to getting the differentiation right - the treatment (cardioversion or amiodarone) is the same for SVT and VT.  And you won’t look as cool as you think you will, like a paramedic Babe Ruth calling his shot.  Anyone that hears your ECG interpretation will assume that you just guessed right through chance, not skill.

The final reason is the most important: It does not matter! 

Cardioversion works for supraventricular tachycardia with aberrancy or with pre-existing bundle branch block.  Cardioversion works for ventricular tachycardia.  Amiodarone works for SVT.  Amiodarone works for ventricular tachycardia.  Adenosine can even convert ventricular tachycardia on occasion! (5)

Simplify!

Your decisions should revolve around whether or not the patient is stable or unstable.  Unstable patients get to ride the lightning – after a benzodiazepine, of course.  For me, the decision to cardiovert someone revolves around their level of responsiveness.  I am very hesitant to weld a patient who is awake, even with midazolam.  But other medics have a lower threshold and include chest pain as a sign of instability. 

If the patient is stable, your next decision is pretty much to think about adenosine, roll your eyes and skip the adenosine, and then start an amiodarone drip.  There are some decisions that revolve around whether the presenting rhythm is regular or irregular, but that decision is in the ACLS treatment algorhythm in order to avoid giving adenosine (or other AV node blockers) to atrial fibrillation with pre-excitation.  You can avoid those problems by just not giving adenosine.

The differentiation of WCTs can be a fun skill to have.  But you have to remember that it is a skill applied after you have dropped the patient off at the hospital.  It is a skill made for debating with your partner at the ED dock or in the front of a bus at post.  Not when you are in front of a patient. 

Instead of studying the ECG that your monitor just printed off, think about what else you could be doing.  Prioritize your actions.  The patient above, at the beginning of this post, has a pretty long list of required actions.  They include oxygen, IV access, possible blood draw, a complete physical exam, a complete history of the present illness, a complete health history, at least one 12-lead ECG, aspirin, consideration of nitrates, a phone call to the receiving hospital so that they are ready, considering/prepping an amiodarone infusion, repeat vital signs, constant monitoring, and extrication from wherever they are to the ambulance.  Pretty much all of those would take higher priority than ten minutes of studying a field ECG with a magnifying glass and a pair of calipers.

My heart-felt advice is to treat all wide complex tachycardias as wide complex tachycardias, rather than trying to differentiate whether it is a ventricular or supraventricular origin.

*V_i is the height/depth of the QRS after 40 milliseconds; V_t is the height/depth of the terminal 40 milliseconds.  Want to measure those while bouncing down the road, do you?

1. Brugada P, Brugada J, Mont L, Smeets J, Andries EW. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation. 1991; 83(5): 1649-1659.

2. Blomström-Lundqvist C, Scheinman MM, Aliot EM, Calkins H, Camm AJ, et al. ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias… J Am Coll Cardiol. 2003; 42(8): 1493-1531.

3. Vereckei A, Duray G, Szénási G, Altemose GT, Miller JM. Application of a new algorhythm in the differential diagnosis of wide QRS tachycardia. Eur Heart J. 2007; 28(5): 589-600.

4. Griffith MJ, Garratt CJ, Mounsey P, Camm AJ. Ventricular tachycardia as default diagnosis in broad complex tachycardia. Lancet. 1994; 343(8894): 386-388.
5. Marill KA, Wolfram S, Desouza IS, Nishijima DK, Kay D, Setnik GS, et al. Adenosine for wide-complex tachycardia: efficacy and safety. Crit Care Med. 2009; 37(9): 2512-2518.