Pacer Safe Mode

Diathermy

by piglet22 - 2024-08-11 05:35:39

I can't really comment on the operation itself, but the last time I had sight of my hospital medical records, the front page had a prominent red label saying "No diathermy"

At the time the label went on, my first pacemaker was probably too old for for interference with newer Bluetooth equipped devices.

Possibly it's a general warning they add.

Some diathermy appears to use frequencies (2.4-GHz) which is the same as used by Bluetooth so given the proximity and the energy, it could pose a problem.

The higher frequencies have shorter range, but certainly far enough to pose a problem for anything in say a 10 metre radius.

2.4-GHz is mainly used, a lot, for data, but certain frequencies including 2.4-GHz are reserved for ISM (Industrial, Scientific, Medical) purposes.

Most of this is speculation, but the warning always sticks in my mind.

My Aunt had the same op and continued to have a long and healthy life, including a pacemaker.

Good luck 

A difficult decision

by Gemita - 2024-08-11 06:59:57

Stache, in view of your recent medical history and difficulties during pacemaker checks, what I believe is important is that you have a pacemaker technician with you for the entire thyroid procedure if you decided to go ahead.  If any adjustments to your device are necessary, the technician can do this at any stage, to keep you safe. You will need to stress the importance of having an experienced technician available at all times.

Have a look at the attached Pacemaker Club post.  You will see member Grateful Heart has given good information and a useful link on Electrocautery and pacemaker devices (Boston Scientific) but it will no doubt apply to other device manufacturers also.  Speak to your team, get all the necessary paperwork sorted and talk to all parties to make sure that you go into this fully aware of the benefits and risks and that you will give yourself the best possible chance of benefitting from your surgery while remaining safe.  

The second link gives useful info on programming options whenever electrocautery is used with pacemaker patients.  I hope the links address some of your questions?

https://www.pacemakerclub.com/message/32629/turning-off-the-pacemaker-during-thyroid-surgery

https://www.bostonscientific.com/content/dam/bostonscientific/quality/education-resources/english/ACL_Electrocautery_and_Implantable_Device_Systems_061908.pdf

Doesn't sound optimal

by crustyg - 2024-08-11 08:34:41

There is a real concern that the diathermy will induce enough interference in your leads for your PM to register heart-derived pacing impulses and stop producing pacing impulses for you.  Not good.  Hence the need to put your device into Safe mode - the same mode as is used for MRI scans.  Your device stops sensing pulses and just paces you at a fixed rate.

OK, so what would be a sensible vent-pacing rate for you, given that you have 3rd degree HB (i.e. CHB)?  The issue is that, since the PM has been set to not sense any activations, there is a (very small) risk that your device paces your RV in the refractory period after a natural activation - which you *may* have if you have any residual A-V node impulse generation (aka 'escape' rhythm).  One way to reduce this already very small risk is to increase your PM's lower pacing rate, so instead of 60BPM it paces you at something higher.  There are two ways to do this: just program your device for a fixed pacing rate of, say, 80BPM, *or* activate 'magnet' mode.  Magnet node is a safety function built into most/all PMs: imagine you're out in the countryside, have a nasty accident, and the local medical centre provides first aid.  An observer says that your vehicle was wandering around on the road before leaving and hitting a tree, so there's concern that your PM has run out of battery (low HR causing low BP, causing faintness).  Naturally no-one in the boonies has a PM programmer, but when they put the magnet over your PM it switches to a fixed pacing rate where the pacing rate indicates how close to exhaustion the battery is.  A neat solution.

Thyroid surgery is much better done with no blood obscuring the surgeon's view, so a lowish BP would ideal, *but* it also requires fanatical attention to tiny little bleeders - the operating area needs to be completely ooze-free before they close the skin.  *IF* you start oozing after the surgeon has closed the skin the build up of blood can start to compress your airway (trachea) and eventually this could kill you.  Trouble with tiny arteries is that compressing them with a clamp can put them into spasm (they have smooth muscle in their walls), which passes off long after the surgeon has closed you up.  Raising your HR, and hence your BP, might not be ideal during the operating phase, but perhaps a good idea towards the end.

The EP-tech will have to program your device to put it into Safe mode.  So using the magnet response doesn't really achieve anything that couldn't be done when setting you into Safe mode.

Choice of pace rate while in Safe mode is difficult.  In preparation for my most recent MRI the EP-tech suggested activating my RV lead (paced AAIR) which I thought very unwise.  After a long discussion and check with the duty EP-doc we agreed to pace my RA at 80BPM in safe mode, after I'd been warned about the risk of this producing AFib!  As though the risk of provoking VF wasn't worse!  (I can still generate junctional pacing up to 115-125BPM, so for me the risk of VF was much greater than the risk of AFib, and a lot less dangerous).

For you, the 'best' RV pacing rate depends on your tendency to generate junctional beats.  If you can pace yourself then you're stuck with a relatively high RV pace rate.  If you have no junctional impulses then 93BPM sounds too high to me.

But all of this is a side distraction.  In my experience of assisting with thyroid/para-thyroid surgery, the choice of surgeon is critical.  You do not want someone who does 10 thyroid ops each year.

pacer rep

by Tracey_E - 2024-08-11 17:21:52

Can someone who can program the pacer be there during the surgery? They would have a lot more control than someone who doesn't know pacers with a donut magnet.

Tracey

by piglet22 - 2024-08-11 20:09:53

It will be fine 

The Gods will prevail.

Praise be doughnuts.