How to make vulnerable and often desperate patients understand the risks and benefits of DBS? The challenges of informed consent
Informed consent is a fundamental requirement of modern medicine. Patients or an authorized proxy should agree to the procedures that will be performed based on a reasonable understanding and appreciation of the risks and benefits the intervention entails. In cases where the disease process itself impacts cognitive function or disturbs mood such as in psychiatric disorders or Parkinson’s disease, informed consent poses a challenge. However this does not rule out efforts to allow patients to participate actively in decision making. In order to optimise the informed consent process, patients and their caregivers can be directed to reliable and accurate on-site, off-site or online resources (counselling, support groups, resource centres).
Deep brain stimulation is an approved and effective neurosurgical intervention for motor disorders such as Parkinson’s disorder and essential tremor. It is an experimental procedure for the treatment of a number of psychiatric conditions, namely treatment refractory depression. In Parkinson’s disease, DBS alleviates some of the symptoms of the disorders and may improve the quality of life in daily tasks, but does not cure. It is an invasive and expensive procedure usually used as a last resort treatment, when medication and all other treatments have failed.
A number of risks are associated with DBS. Complication rate can exceed 25% and permanent neurological sequelae results in 4% to 6% of cases. The risks of DBS entail surgical complications (paralysis, intracranial haemorrhage), postoperative complications (infection) and hardware failure (electrode malfunction). It is thus important that patients or proxy decision makers understand all aspects of the procedure as well as what will be expected from them before, during and after surgery.
Patients should also understand issues related to the device itself. The electrodes implanted in the brain are connected by very small wires stimulated electrically by an implanted pulse generator. This generator is implanted in the upper section of the chest and is activated by a battery. The lifespan of this battery is approximately 5 years after which it needs to be replaced in a less invasive, often outpatient, surgery.
Since DBS is a last resort treatment, health care professionals are likely to be confronted with desperate patients who may be willing to consent to anything in spite of substantial or unknown risks. Beneficent guidance is essential here to avoid unacceptable risks for patients or pressures from overburdened caregivers. The surgical team should be prepared to tackle pressure from patients and caregivers when DBS is not in the patients’ best interests from a surgical or medical standpoint.
This text summarises the ethical issues related to deep brain stimulation, developed and discussed in an excellent publication by Emily Bell, Ghislaine Mathieu and Eric Racine. (2009). Preparing the ethical future of deep brain stimulation. Surgical Neurology, 72: 577-586. The summary has been approved by the first author.
|Adapted by :||Myriam Hivon, Ph.D.|
Bell E, Mathieu G, Racine E (2009). Preparing the ethical future of deep brain stimulation. Surgical Neurology, 72: 577-586.