turning off an implanted cardioverter defibrillator (ICD)

Kavod HaRabanim

I would like to pose to you the following clinical situation for an opinion on the halacha.

By way of background, I am an advanced trainee in cardiology and cardiac electrophysiology working in Australia, in an area almost exclusive populated and staffed by nochrim.

I was asked to see a patient with view to turning off her implanted cardioverter defibrillator (ICD). She was a woman of 89 years who had been diagnosed with advanced lung cancer and had become profoundly confused. Her prognosis was estimated at weeks, with a possibility of days. It was felt by the medical staff and family that it was in the best interests of the patient, and was consistent with her views on life and death, that she be treated palliatively.

One year previous, a cardiologist at a different institution had implanted the ICD for 'primary (sic) prevention' of ventricular tachycardia/fibrillation, owing to her sever left ventricular dysfunction. I might note at this stage that I am unsure when the cancer diagnosis was made, but I am sure that this patient would not have been considered for an ICD in our hospital in any case. Over the past year, the patient had not had any VT/VF detected on the ICD and no therapy was given for arrhythmia.

Our request to turn off the ICD happened on a Friday, stating that the patient was due for transfer to palliative care hospice on the Monday and turning the device off that day was ideal. Over that weekend, she had two losses of consciousness. Interogation of the ICD showed two episodes of ventricular fibrillation that were appropriately and successfully treated with internal defibrillation.

My questions are manifold. Is there are concern about turning off preventive devices, in our case an ICD that is not (at the moment of reprogramming) delivering therapy. Secondly, does it make a difference whether the device is for primary prevention or secondary prevention? Furthermore, does it make a difference whether the device has, so far, been effective in aborting sudden cardiac death? Does the fact the patient is khola sheyesh ba sakana or even a goses matter? Finally, what effect does is have if the patient is a non-Jew?

If you have any questions about the evidence and practice pertaining to ICDs, please don't hesitate to ask.

I thank you very much for your time in consideration of this case. I look very to your reply.

Kol Tuv