Case scenario: Your 60 yoM patient has symptomatic bradycardia (ie is acutely altered, has significant CP, acute HF, dizzy/diaphoretic, or hypotensive with positive airway, breathing, & glucose) is dependent on the transcutaneous pacer and now you need to transfer them to a flight crew.
So what is the best way to do this and the safest way for the patient given their external electrical dependency?
Well, there isn’t much helpful EBM on this other than my own level V evidence (ie flight physician opinion).
First of all, I give a big ol’ high five to the medics for getting this patient paced in the 1st place. Not only is this rare but it takes some cojones to place a patient on a pacer and since they are being paced then I know they were unstable and you now stabilized them… so good Job!!! High five’s all around! Not to mention you gave your patient appropriate analgesia and sedation so that they are not moaning with each electrical impulse, you ran a 12 lead, started an IV, you checked a blood sugar, and you got them out of their house… Strong work! Now, since you just can’t give me your pacer machine, because you need it to stay in service and they are pricey, we are going to have to switch them over to ours. Also, all the electronic medical equipment in a helicopter has been tested yearly (on take-off and landing) to make sure that it does not interfere with the instruments used to fly that aircraft therefore flight crews would be less likely to take another systems monitor if it was a different manufacturer. The last thing we would want is a medical device (monitor, epocs, warmers, vents, pumps, ultrasound machines, cough assist machines, portable suction devices etc.) affecting our ability to fly or navigate. Here is where pre-planning is key and slow is smooth and smooth is fast.
Set up another set of pads on the patient. As you recall pads can be placed in the left anterior-posterior or the right anterior chest and left axillary positions.
Set a second set of pads in the other orientation on the patient’s chest. Try to keep those pad wires away from the front of the heart as these can then interfere with the cardiologists view, in case this patient is going to the cath lab. Also attach the sensing lead cables (white, red black, green) based on your type of monitor. These will be needed to sense while the pads will be delivering the pacing.
Now one little glitch that a colleague of mine ran into one was that our pacer machine setting did not go as high as another manufacturer’s machine (this is where AP pad placement may be more beneficial given that the electricity can travel through a shorter path). If AP pad placement doesn’t work and the patient needs a higher output setting then they might be stuck on that higher output machine and need to either fly with that machine or go by ground.
So, if able to, set the same output and rate and then set the pacer on demand mode. Demand mode will pace the patient at a set rate when needed rather than having one set pacer rate and ignoring the patient’s intrinsic rate. Think of this like an SIMV mode for pacing, where it allows the patient to have some of their own beats.
The reason to do this is 2 fold: 1) This allows the patient to have some of their own intrinsic beats thus allowing a 12 lead to demonstrate their own intrinsic rate and rhythm 2) this allows us to see if any of the other interventions (atropine, vasopressors, glucagon, electrolyte corrections, fluids, home meds etc.) have worked in the interim while they were being paced on the initial machine.
Once everything is set up in a double fashion then turn one pacer off immediately turning the other pacer on. If you have universal pads then you can simply switch the pads connector from one machine to another, but then you have no backup if the new machine does not capture.
Make sure to keep your hand on the patient’s (femoral is recommended) to confirm that there is continued mechanical capture, in addition to the electronic capture seen on your monitor. The Pleth wave from your pulse ox works awesome as well!
One other thing that has been mentioned in the literature is that ETCO2 can be monitored and tracked with these cases. If you had your patient off of the pacer and then had capture you may see a spike in your ETCO2 due to increased perfusion (remember, now you have mechanical capture and more tissues are being perfused thus more CO2). When transferring your patient to another pacer or monitor, take note of the ETCO2 value and make sure it does not drop. If it does then it could be that you have lost mechanical capture. Luckily, you are feeling for pulses at the same time too, right?
Other little pacer/AICD pearls: If your patient has a pacemaker or an AICD and you have placed a magnet on their chest (In the case of AICD – to stop it from discharging for excessive tachycardia's yet will not inhibit the pacing function, In the case of Pacer alone – to stop it from sensing the patient’s own rate and default to a set asynchronous rate) then this MAGNET needs to be removed prior to placing this patient in or around the helicopter. Make sure that this magnet is not wrapped up in the sheets or hidden on the patient. You do not want that magnet to interfere with the helicopter instruments. I had one pilot say “you’re not bringing that magnet on my aircraft unless it’s been tested” and I had another say “but it’s in the back and a magnet, no biggie”. So, please check with your pilot and the type of aircraft you are in regarding the magnet. To date there are no published studies recommending for or against these magnets in aviation. To find out more about using a MAGNET with AICDs and Pacers check out the following quick video at https://coreem.net/procedures/how-to-use-a-magnet/ So will the aircraft or exogenous electromagnetic signals interfere with a patient’s internal or external pacer? Not according to the evidence which is sparse yet there is this one case that I found regarding aviation and a pacer that did not disappoint. There was this case report by Roche, et al about a man on a plane whom found out that every time he tried to recline his seat he got sick and fainted. When calling for physician assistance on the plan an orthopod responded and tested the seat and deemed it appropriate, go figure. Then a psychiatrist responded and concluded the patient had flight anxiety, go figure again, jk =P. Come to find out what the patient really had was interference (discovered with pacemaker interrogation later on by his cards doc) which inappropriately inhibited his pacemaker and thereby prevented the delivery of cardiac stimulation in his unipolar pacer leading to asystole. So every time he went to lower his seat he had just a little bit of asystole. Just a little. Nowadays pacers are bipolar and have an intrinsic set rate so this is rarely an issue. Bipolar systems have been shown to have a smaller risk of electromagnetic interference. Either way, you might want to keep this in mind for when you are on your next flight.
Cynthia Griffin DO, NRP @CMGrffn Refrences: Betkas F, Soyuncu S. The efficacy of transcutaneous cardiac pacing in the ED. American Journal of Emergency Medicine 34 (2016) 2090-2093 Hedges, Jerris et al. Prehospital Trancutaneous Cardiac Pacing for Symptomatic Bradycardia. PACE Vol 14, Oct 1991 1472-1478 Roche N, Thabouillot O, Bouvier F, Paule P. Prepare for Take-Off: Fasten your seatbelt and keep a magnet in your pocket. Preospital & Disaster Medicine 2017 Toff WD, Edhag OK, Camm AJ. Cardiac pacing and aviation. European Heart Journal (1992) 13, 162-175 Articles I could not see due to limited access: Gordon RS, O’Dell KB, Low RB, Blumen IJ. Activity–sensing permanent internal pacemaker dysfunction during helicopter aeromedical transport. Ann Emerg Med 1990 Nov; 19 (11): 1260-3 Sumchai A, Sternbach G, Eliastam M, Liem LB. Pacing hazads in helicopter aeromedical transport. Am J Emerg Med 1988 May; 6(3):236-40