Part 1 of the Conclusion to 15 year old male CC: fall from vehicle

This is Part 1 of the conclusion to 15 year old male CC: fall from vehicle.

Lots of great comments, including an unexpected sidebar discussion on appropriate C-spine clearance! All of our cases on EMS 12-Lead have been altered from their original form to protect patient and provider privacy and it appears I changed things enough to give a different focus. So let's quickly touch on the consideration of spinal immobilization in this case.

Given an alert and oriented patient, normal neurological exam, negative pain to the C-/T-/L-spine, no distracting injuries, and no intoxication, it is not unreasonable to forgo immobilization in this patient. When our story contradicts our patient presentation, we should find the middle ground. Given our physical findings consistent with a more moderate mechanism an unstable spinal injury is unlikely. Yet, given provider suspicion it is also not unreasonable to place this patient into spinal immobilization. I think you can sell it either way.

However, the patient presentation in this instance was meant to be a distraction for our readers! Let's revisit the first strip to see why:

We've only got one lead, and as some commentors noted there is a lot of artifact. However, lead II has some clear parts with interesting findings that one of the crew members marked up!

We can see regular atrial activity and regular ventricular activity, yet it seems off. Many readers pointed out the likely cause is a 1st Degree AVB with artifact. Based on this strip alone that is the most reasonable explanation. However, as everyone pointed out, it would be prudent to get a cleaner strip and a 12-Lead to confirm our suspicion.

At first glance, our next strip points to uncomplicated 1st Degree AVB. However, as one of my instructors often pointed out, "the PR-interval will not progressively shorten." A closer look at the second strip shows a progressively shortening PRi which eventually prolongates again!

This cannot be an uncomplicated 1st Degree AVB.

By our third strip it is obvious we have something more than a simple prolonged PRi. Leads II and III show hidden P-waves marching out from underneath the QRS complexes. We now have more P-waves than QRS complexes, leaving us with at least a 2nd Degree AVB or a 3rd Degree AVB.

The next two strips were sent in but not included in the original discussion, however, I hope they foster additional discussion as to which high-degree AV block is present.

In the above strip, compare leads II and III closely. Contrast that with your findings in the below strip:

  • Given our findings does the argument for a 1st Degree AVB still stand?
  • Is a 2nd Degree AVB or 3rd Degree AVB present? Could both be present?
  • If it is a 3rd Degree AVB is it complete or is there occasional capture?
  • Is it reasonable that our patient's traumatic injury is the cause of these isolated findings on the ECG?


  • Jim Bianga says:

    I see a 2nd degree 2:1 in the second strip. I would monitor and transport to the nearest ER because the pt has stable vitals.

  • The New Guy says:

    With the P-P regular and the R-R regular adding the fact that there are more P waves than R waves and the PRI is shortening though the strip I'm voting for 3rd degree block with a junctional escape rhythm in the second to last strip but the PRI looks to become regular in the last strip. Perhaps he reverted to a 2nd degree un-typable rhythm. Either way it is a high degree block with high risk of other dysrhythmias. Continue to monitor pt and transport to the nearest ER for evaluation from a cardiologist.

  • Newer EMT-I says:

    I'm a pretty new Intermidiate…but with those strips I would say 3rd degree.  They seem evenly distributed.  the rate seems a bit high for 3rd…but could be.  I would go with O2, Line, Pads on and ready, and Atropine for good measure…transport to the closest appropriate facility.

  • James says:

    Looks more like arial flutter 2:1 with a 1st degree AVB

  • C Younger says:

    Every strip so far shows persistant complete AV Block.  Again, his atrial rate being almost exactly double the junctional escape rate makes it more difficult to appreciate.  At his age, excessive Vagal tone should be considered but also an electrophysiological study should be obtained once cleared from trauma. 

  • Cortney says:

    I'd agree with James. 2:1 A-flutter with a 1st degree AVB… answer!

  • Ryan says:

    This is a 2nd degree type II. The PR Interval is unchanging making it unlikely to be a 3rd degree block. 

  • Ryan says:

    It's not A-flutter with 2:1 conduction. That would cause a rapid heart rate. The kid is bradycardic, which should be a clue that this is a block. 

  • wrmedic82 says:

    I am going with Second degree Mobitz type II
    What puts the nail in the coffin is the fact there IS a consistent PR interval with the exception of the blocked beat. With that being said, you cannot truely say there is any AV disassociation at all. Pt's heart is sick and treatment maybe geared toward going to a facility that can do transvenous pacing, and consider pacing enroute.

  • Tammye Erdmann says:

    I also agree that the consistent PR interval associated with the conducted beats indicates this is a 2AVB type 2. 
    As for the conversation about atrial flutter ~ my thought is that the atrial rate is too slow by definition to be atrial flutter. Flutter normally demonstrates an atrial rate of greater than 220 to 240 bpm. The atrial rate demonstrated in these strips is much slower that that.
    I like the idea about increased vagal tone….makes sense to me and I saw a case of increased vagal tone for a young male trauma patient once but the rhythm demonstrated was asystole not heart block. This could be…..
    I would also consider a myocardial contusion leading to the arrhythmia seems that would be worthy of an investigation.

  • wrmedic82 says:

    I will add this after looking at the 2nd EKG there is a narrowing of the PR interval. This tells me that the Pt's heart at some point was firing from a different atrial foci other than the SA node which may be due to injury. But even when you measure those intervals prior to the change and after the change. The PRI is constant.  Also look at the P waves before the narrowing of the PRI. The P waves appear to have a more round morphology which supports the idea that the P waves where coming from a foci that is high atrial, but not from the SA node.

  • OldSchoolMedic says:

    People, quit trying to read too far into it.  This is a 3rd degree HB.  Whether congenital or traumatic in origin is for the ER doc and the cardiologist to decide.  Treat the kid for his presenting complaints and injuries and transport to local facility for evaluation.
    Bottom line, whatever ails this kid isn't going to be cured in the back of the box. 

  • RyanZ. says:

    I'm going with a 3rd Degree HB, it's pretty obvious that the P wave and QRS complex are operating independant of each other. Cause doesn't matter at this point, treat the patient, and go to a cardiac specialty center. 

  • BigWoodsMedic says:

    I have to agree with OldSchoolMedic. It's a startling rhythm to see on a 15 y/o, who I personally would have immobilized regardless of his non-complaint. Certainly this rhythm being traumatic in cause is running through my mind. I'd prefer to take him to a hospital that at least has a cardiology consult if I have a reasonably distanced choice. 

  • Jeep Medic says:

    As I look over the new EKG and the ones from the original story I have to agree w/OldSchoolMedic.  The P's march out and the Q's march out, but not in time w/eachother.  Look @ what it is on the monitor, advise medical command, & charlie mike….follow your protocols and get the kid to the ER.  
    Oh and a 45mph ejection from a moving vehicle and no c-spine immobilization???  Wow!!!!!!  But that was the original crews call. 

  • HawkeyeEMTP says:

    Atropine at the ready?  If you think it's a 3rd degree AV block, atropine would have little to no effect.  Unless, of course, you think he's going to go PEA/asystole on you.

    My final answer will be  that it is a high-grade or advanced AV block, a gray area between a 2nd degree type II AVB and a 3rd degree AVB.  Although, this is hard to tell because to meet that criteria, there needs to be 2 consecutive P waves dropped which we do not see.

    A high-grade AVB is used when the rhythm wanders between blocked P waves and a 3rd degree AVB.  Looking at how the rhythm changes between the first strip and the last.  I'd say it's doing just that.

    Continue monitoring vitals, keep the pads close by just in case.
    I think there's this debate because it falls in this very rare gray area, a common area of debate even between cardiologists.

  • Ryan says:

    I’d like to change my answer from Mobitz II to a complete 3rd degree AVB. The last strip shows a consistent PR Interval but when you look at the first strip you can see that the PR Interval IS changing. The p waves march out with themselves, and the QRS march out with themselves but they do not match up. With the last strip alone I would say its impossible to distinguish whether or not its Mobitz II or 3rd Degree, but after looking more closely at the first strip and seeing the variable PR interval, I’d bet that this is a complete 3rd Degree. I’d at least have the pads ready to TCP just in case. The kid seems stable but that can quickly change.

  • Nick Adams says:

    Oh my……everyone is finally agreeing…lol.  I've seen a few patients who presented with a 2nd degree type I and then a 2nd degree type II.  I've also had a simular case where a pt was going back and forth between a 2nd II and CHB, just as this one is.  Every other one goes through for a while, then all get blocked for a while….back and forth back and forth.  It happens.  Why do some providers think that it has to be JUST a 2nd degree type II or JUST a CHB?  As for the full spinal precautions, no doctor would chew you out for long boarding him.  I prefer to do a thorough assessment and physical exam before making any treatment decisions.  
    Bigwoodsmedic –  Well said.  I would also prefer transporting this patient to a facility that is reasonable close with cardiology capability.
    Could be congenital or secondary to a cardiac contusion from the force of the heart smashing up against the spinal colum when the patient landed on his back.  Would love know if he had an echo and what the results were. 

  • Dave B says:

    Sinus tach, with varying degree of first degree AV block… 2:1 AV nodal block probably due to interference. even though the PRI is gradually changing, they are related in each strip and not random. this leads me to believe that the sinus node is conducting, but slowly. PRI of even 400ms is not unheard of.  in almost all strips, there is a reciprocal relationship between the PR and RP intervals. where the PR is shorter, the RP is longer, and vice versa.  this puts the block in the node.  due to the first degree block, possibly due to congenital problem, at this rate, every second P happens to come during the absolute refractory period of the QRS, and is not being conducted.

  • VinceD says:

    Brandon, I think your "higher threshold for incredulity" payed off, and after pouring over the first post and getting a sneak peak at these, my interpretation changed to match your's. Good point about trying to make the data fit what I wanted to see, it's exactly why I missed the diagnosis on the first go-round.

  • Metamucil Medic says:

     In my system, since he's15 yo, he should go to the pedi facility (2 pedi facilities, both Level I, are each 30 mins away), but I'd opt to take the pt to a Level II trauma center. The local hospital is one step above (or below depending on who is in the ER) a Doc-in-the-Box and the Level II trauma centers are 12 and 16 minutes down the road.
    What bothers me is that the ecg keeps changing, he was thrown out of a moving vehicle at 45 mph and his case is presented on  I guess I'm more consertative, but I'd board him (with all the appropriate stuff), shoot for less than 8 min onscene time and transport non-emergent to a Level II. Enroute, I'd hook him up to all the wiz-bang stuff, O2 NC, IV TKO and observation.
    Just cuz a pt does not meet the criteria for required transport to a trauma center does not mean that you can't go there anyway. Many, many times I've placed my self in front of a curve ball that never appeared, but the few times it actually showed up was worth it.
    Side note: I readily admit that paramedics coming out of school in the past 10 years or so are much, much more learned than me (when I started, we didn't have 12 leads, pacing, SPO2, glucometers, etc). I've noticed that older medics rely more on what we see, hear, feel and newer medic rely more in numbers.  Just an interesting observation from a guy who trys to keep up with the smarter medics 🙂

  • Bryan says:

    Some rhythm strips show Morbitz II, some CHB with junctional escape complexes.  The QRS morphology seems unifrom unless by measuring the R to R interval we can infer or observe a P wave marching through.
    I don't see any indications in the case for trauma centre activation.  The MOI does not replece a thourough assessment.  Given the detail of this case, SMR is unnecessary.
    I suppose blunt chest trauma could case electrical dysfunction of the SA node and/or the AV node?  I'm not certain if it would be transient and self limiting?
    Transport to local ED no light and sirens for evaluation, maybe saline lock TKVO.

  • Rose says:

    I was able to find some case studies of traumatic causes for a complete heart block in young children.  One child fell from a fire escape, both presented to the ED with a complete heart block that resolved after 3 days. 

  • Billy Bob says:

    i dont see what everyone else is; if its a 2nd degree he should be dropping a beat whether its type 1 or 2 (which he is not). As for the 3rd degree the rate is to fast, and given the PRi is long then short ect each p still has a qrs. As for the p's burried at the bottom of the qrs i think were just fishing now. The kid is asymptomatic so leave him be and let him follow up with a cardiologist. WPW and atrial arrythmias are out the rate is brady? It's a first degree plain and simple.  

  • James and Courtney,

    Atrial flutter, by definition, will have atrial rates >250 bpm. Rates below this are deemed atrial tachycardia. The most common atrial rate in flutter is ~300 bpm and the most common conduction ratio is 2:1, lending to the common ventricular rate of 150 bpm.

    The atrial rate in these tracings stay at or below 120 bpm.

  • Billy Bob,

    You can have complete heart block and ventricular response at this rate. The narrow complexes are from a focus lower than the block but still in the junction. You can even have tachycardic rates if the junctional pacemaker increases its automaticity.

    WPW does not preclude bradycardic rhythms, it is merely a condition involving a bypass tract and a hieghtened risk for tachyarrhythmias.

  • Ryan,

    While I agree this is not atrial flutter, the definition does not depend on the ventricular response. You can have a bradycardic response with atrial flutter given a lower conduction ratio (any greater than 5:1).

    Additionally, you can have any number of AV nodal problems with atrial flutter, including 3rd degree AVB. This means you could have atrial flutter with F-waves at a rate of 300 with a wide ventricular escape of only 40 bpm!

  • To those suggesting trauma as the cause,

    When I first saw the strips and the nature of the call, I jumped on a traumatic cause. It just seems interesting that in the face of normal vitals and an unremarkable physical assessment that the patient did not already have this rhythm to begin with.

    If the patient acquired this heart block due to trauma, it would stand to reason their body had grown accustomed to a certain level of ventricular response. After the trauma, they now have a decreased ventricular response. I have trouble reconciling the seemingly asymptomatic patient with a new onset heart block! Now perhaps being 15 years old helps, but my gut says they would be showing some signs of trouble compensating.

    Compare this with a 15 year old who already had AV nodal problems, a junctional escape rhythm would be the norm. We can reconcile our patient presentation with this theory.

    But as OldSchoolMedic and others pointed out: we can't know for sure in the field!

  • VinceD says:

    Christopher, I had the same dilemma while trying to figure out if this would be the kid's baseline (sinus @115bpm, vent @60bpm) or if he typically ran with an atrial rate in the 70's and was now sinus-tachycardic after the accident, but with a junctional pacemaker that just wasn't compensating the same way. I too would say it's highly unlikely that someone who's heart rate is only half of what the sinus node apparently wants it to be would look as well as this kid does unless the condition was chronic, but then again, I haven't seen too many (zero) kids with an ECG like this.

  • Hodgie says:

    I have to go with a 3 degree AVB with junctional escape. As far as if the trauma caused it, I don't know. But, if it is new I would think the patient would be at least a little symptomatic. The slow rate and loss of atrial kick would be a lot for a kid. Treatment, spinal precautions, IV, O2 12 lead!!!!!! and transport to a pedi center.
    Also, I saw a post about Atropine for a 3 degree. Never!!!! 

  • SAP says:

    I see 3rd degree block. 2:1 block should be a differential, but the PRi of every second P is inconsistent.

    On the subject of immobilisation, I personally cannot stand immobilising on mechanism alone, and have left a motorcyclist who crashed at 70mph on scene (across the pond from most of you guys), because he was uninjured. Certainly I think we’re a lot happier not to immobilise over here.

  • arnel says:

    Atrial tachycardia

  • Terry says:

    Nick and Chris,
    I stand corrected from the last post on narrow qrs and CHB. This patient definitely meets the criteria for a trauma team activation due to the ejection at 45 mph. I am well aware of the nexus protocol and the need to do a thorough assessment. MOI—high index of suspicion— this kid would definitely have me on high alert. Don’t know many medics that would call a trauma team and not put the patient on a board. Actually in our system the hospitals will not call a trauma team based on the medic but on VS and MOI. We don’t like it but it is probably from too many false activations. Treat the patient not the monitor and get him to a trauma center.

  • Nick says:

    Tom, the 2 extra strips u provided almost looks like nonconducted atrial bigeminy! But my final answer is 2nd Degree Type II with intermittent 2:1 and 3:2!

  • Baker says:

    I know that sick sinus syndrome usually only effects heart rate,  but does anyone think that it would be possible for it to have an effect on PR interval as well,  im with Christopher im not sold on the fact that the trauma caused this rhythm.  Another tthought is wandering atrial pacemaker,  could this be a congenital defect that the pt has had all along and has just never been noticed,  i doubt he has been on a cardiac very many times in his life being that he is only 15.

  • martha says:

    2nd degree avb type II, with 2:1 av conduction blocks, VS atrial tack 2:1 sa blocks.

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