Monday, June 30, 2008

Deactivating ICD guidelines

Continuing our intermittent practice of reviewing of treatment guidelines/consensus statements for mentions of terminal care/palliative care, a multiple-organization consensus guideline about implantable cardiac devices has recently been published in Europace (free full-text here). There is a lengthy section on ethics of device deactivation, decision-making around that, etc. It is pretty straight-forward, and treats implanted devices as medical therapies like any other, and can thus be discontinued after careful consideration like other therapies (it avoids the whole these-things-are-implanted-therefore-become-part-of-you-and-thus-subject-to-unique-ethical-analysis debate).

In addition the panel argues that continuation of ICD therapy may be indicated even in patients with DNR orders under these conditions:

  • The arrhythmias being treated reflect the primary cardiac condition and not an irreversible secondary medical illness;
  • Prompt ICD therapy confers the likelihood of added survival with meaningful quality of life and without post-arrest disabilities (e.g., cognitive); and the patient concurs with this approach.
There seem to be two distinctions being drawn here.

First if patients are dying of another condition (e.g. cancer) who also have a cardiac condition (recurrent V. fib) and who don't mind being shocked if their 'fib acts up' it may make sense to keep the ICD activated.

Second, there seems to be a distinction here between a patient having an arrest/arrhythmia which is ICD-shockable and them having a 'real' arrest (becoming pulseless, etc. - something someone would want to do CPR for). I.e. there's a difference in prognosis/likely outcome between the two scenarios: this makes sense on its face but I'm not 100% sure that that's accurate. In my experience the frequency of either of these two scenarios occurring is very small (e.g. the patient's prognosis is so short when the DNR order is being established that the likelihood of the patient benefiting from ICD therapy is negligible), but it's a big world out there and I'm sure there are cases in which this would make sense.

One thing they didn't mention, which I'm still looking for in a publication, is how to counsel families how to deactivate them in emergencies (cancer patient is rapidly dying at home; burden of transport to ED or clinic to deactivate ICD is great; family - with presumably treating physician support - wish to deactivate ICD in-situ). I get asked this from time to time, mumble something about a magnet, but never know how strong of one, etc.

(Incidentally, there was also this recent paper in Pacing and Clinical Electrophysiology, which is a survey of clinicians about practices regarding discontinuation of device-therapy - I have only read the abstract. These subjects reported that about half the time it's the manufacturer's rep who does the deactivation.)