No full-text available
To read the full-text of this research,
you can request a copy directly from the author.
Informed Consent for Deep Brain Stimulation: Increasing Transparency for Psychiatric Neurosurgery Patients
Abstract
What should a patient know before he or she allows a physician to control a part of the patient's brain? While this sounds like a philosophical thought experiment designed to twist the intuition, it is meant to address the ramifications of a widely used clinical therapy called deep brain stimulation (DBS). Deep brain stimulation is a therapy, approved by the Food and Drug Administration (FDA), to relieve the symptoms of movement disorders, specifically dystonia [1], essential tremor [2], and the effects of Parkinson disease [3], and is currently being studied for a wide variety of psychiatric illnesses [4]. DBS is complicated to employ, requiring the coordinated effort of a team of health care professionals, chiefly a neurosurgeon, a neurologist, and a neuropsychologist.
ResearchGate has not been able to resolve any citations for this publication.
For patients with psychiatric illnesses remaining refractory to 'standard' therapies, neurosurgical procedures may be considered. Guidelines for safe and ethical conduct of such procedures have previously and independently been proposed by various local and regional expert groups.
To expand on these earlier documents, representative members of continental and international psychiatric and neurosurgical societies, joined efforts to further elaborate and adopt a pragmatic worldwide set of guidelines. These are intended to address a broad range of neuropsychiatric disorders, brain targets and neurosurgical techniques, taking into account cultural and social heterogeneities of healthcare environments.
The proposed consensus document highlights that, while stereotactic ablative procedures such as cingulotomy and capsulotomy for depression and obsessive-compulsive disorder are considered 'established' in some countries, they still lack level I evidence. Further, it is noted that deep brain stimulation in any brain target hitherto tried, and for any psychiatric or behavioural disorder, still remains at an investigational stage. Researchers are encouraged to design randomised controlled trials, based on scientific and data-driven rationales for disease and brain target selection. Experienced multidisciplinary teams are a mandatory requirement for the safe and ethical conduct of any psychiatric neurosurgery, ensuring documented refractoriness of patients, proper consent procedures that respect patient's capacity and autonomy, multifaceted preoperative as well as postoperative long-term follow-up evaluation, and reporting of effects and side effects for all patients.
This consensus document on ethical and scientific conduct of psychiatric surgery worldwide is designed to enhance patient safety.
Ethical evaluation of deep brain stimulation as a treatment for Parkinson’s disease is complicated by results that can be
described as involving changes in the patient’s identity. The risk of becoming another person following surgery is alarming
for patients, caregivers and clinicians alike. It is one of the most urgent conceptual and ethical problems facing deep brain
stimulation in Parkinson’s disease at this time. In our paper we take issue with this problem on two accounts. First, we elucidate
what is meant by “becoming another person” from a conceptual point of view. After critically discussing two broad approaches
we concentrate on the notion of “individual identity” which centers on the idea of “core attitudes”. Subsequently we discuss
several approaches to determine what distinguishes core attitudes from those that are more peripheral. We argue for a “foundational-function
model” highlighting the importance of specific dependency relations between these attitudes. Our second aim is to comment
on the possibility to empirically measure changes in individual identity and argue that many of the instruments now commonly
used in selecting and monitoring DBS-patients are inappropriate for this purpose. Future research in this area is advised
combining a conceptual and an empirical approach as a basis of sound ethical appraisal.
KeywordsNeuroethics–Deep brain stimulation–Personal identity–Parkinson’s disease–Personality measurement
Deep brain stimulation (DBS) of the globus pallidus internus (GPi) offers a very promising therapy for medically intractable dystonia. However, little is known about the long-term benefit and safety of this procedure. We therefore performed a retrospective long-term analysis of 18 patients (age 12-78 years) suffering from primary generalized (9), segmental (6) or focal (3) dystonia (minimum follow-up: 36 months).
Outcome was assessed using the Burke-Fahn-Marsden (BFM) scores (generalized dystonia) and the Tsui score (focal/segmental dystonia). Follow-up ranged between 37 and 90 months (mean 60 months).
Patients with generalized dystonia showed a mean improvement in the BFM movement score of 39.4% (range 0-68.8%), 42.5% (range -16.0 to 81.3%) and 46.8% (range -2.7 to 83.1%) at the 3- and 12-month, and long-term follow-up, respectively. In focal/segmental dystonia, the mean reduction in the Tsui score was 36.8% (range 0-100%), 65.1% (range 16.7-100%) and 59.8% (range 16.7-100%) at the 3- and 12-month, and long-term follow-up, respectively. Local infections were noted in 2 patients and hardware problems (electrode dislocation and breakage of the extension cable) in 1 patient.
Our data showed Gpi-DBS to offer a very effective and safe therapy for different kinds of primary dystonia, with a significant long-term benefit in the majority of cases.
Despite the best available medical treatments, many patients continue to be disabled by neurologic and psychiatric disorders, resulting in a large unmet need. Advances in imaging and neurophysiology over the last two decades have led to a reinterpretation of some neurologic and psychiatric conditions as primarily disorders of circuit function, or "circuitopathies." These developments have been accompanied by advances in neurosurgical techniques with the increasingly widespread utilization of deep brain stimulation (DBS) to recalibrate dysfunctional circuits. The versatility of DBS as both a probe and modulator of neural circuits is making it a powerful tool to study the human brain, helping provide important details of the pathophysiology of circuit dysfunction. We are currently in a phase of active investigation to determine which circuits and disorders could be treated with DBS. Here we review recent advances in the DBS field and discuss potential future directions in targeted intracranial neuromodulation.
Purpose of review:
Informed consent has become the cornerstone of the expression of patient's autonomy for ethical and sound patient-physician relationships. However, some severe psychiatric diseases markedly hinder the ability of selected patients to ensure a proper consent. Confronted with mentally disabled individuals whose condition may lead to violence or inflicting it on others, society must carry out its duty of protecting those who are particularly vulnerable, while respecting and protecting these disabled individuals.
Recent findings:
The recent update in the indications and more detailed understanding of electroconvulsive therapy, and the technical ability of obtaining less invasive or reversible techniques of psychosurgery, has renewed interest in these impressive and efficient techniques. Specifically, the emergence of new and promising cerebral neurostimulation techniques for treating Parkinson's disease have led to considering their extension to severe psychiatric disorders. This method can mimic the effects of 'conventional' psychosurgery, but in a potentially reversible and adaptable way, thus avoiding many undesirable side-effects of lesional surgery. Ensuring an ethical decision-making process and the appropriateness of consent becomes of paramount importance.
Summary:
Consent can be relatively easy to secure in selected patients who are often fully aware of their torments (such as those suffering from severe refractory depression of obsessive-compulsive disorders) whose suffering may be such that they are ready to accept, or for that matter demand, such actions. However, the duty of physicians is to realize that pains should always be taken to do as much good (and as little harm) as possible, while respecting the freedom of decision of those who seek to help.
Essential tremor is a common movement disorder. Tremor severity and handicap vary widely, but most patients with essential tremor do not receive a diagnosis and hence are never treated. Furthermore, many patients abandon treatment because of side-effects or poor efficacy. A newly developed algorithm, based on the logarithmic relation between tremor amplitude and clinical tremor ratings, can be used to compare the magnitude of effect of available treatments. Drugs with established efficacy (propranolol and primidone) produce a mean tremor reduction of about 50%. Deep brain stimulation (DBS) in the thalamic nucleus ventrointermedius or neighbouring subthalamic structures reduces tremor by about 90%. However, no controlled trials of DBS have been done, and the best target is still uncertain. Better drugs are needed, and controlled trials are required to determine the safety and efficacy of DBS in the nucleus ventrointermedius and neighbouring subthalamic structures.
Many subjects enrolled in research studies have a limited understanding of the research to which they consented.
To develop recommendations to enhance comprehensiveness and understanding of informed consent forms used in critical care clinical trials.
Consensus process.
We provide recommendations regarding the U.S. federally required basic and additional elements of informed consent as applied to critical care clinical trials. We also identify issues that investigators need to address, if relevant, in the informed consent forms of critical care clinical trials. These include the description, in understandable language, of complex and detailed experimental protocols that are the focus of the clinical trial, disclosure of death as a risk factor if mortality is an outcome variable, and the identification of who can legally serve as the prospective subject's surrogate. We also offer suggestions to enhance subjects' understanding of informed consent forms.
The literature on informed consent forms suggest that shorter informed consent forms written at a lower reading level, when read carefully, might provide better subject understanding. Prospective evaluation is needed to determine whether our recommendations enhance the informed consent process.
Neurostimulation of the subthalamic nucleus reduces levodopa-related motor complications in advanced Parkinson's disease. We compared this treatment plus medication with medical management.
In this randomized-pairs trial, we enrolled 156 patients with advanced Parkinson's disease and severe motor symptoms. The primary end points were the changes from baseline to six months in the quality of life, as assessed by the Parkinson's Disease Questionnaire (PDQ-39), and the severity of symptoms without medication, according to the Unified Parkinson's Disease Rating Scale, part III (UPDRS-III).
Pairwise comparisons showed that neurostimulation, as compared with medication alone, caused greater improvements from baseline to six months in the PDQ-39 (50 of 78 pairs, P=0.02) and the UPDRS-III (55 of 78, P<0.001), with mean improvements of 9.5 and 19.6 points, respectively. Neurostimulation resulted in improvements of 24 to 38 percent in the PDQ-39 subscales for mobility, activities of daily living, emotional well-being, stigma, and bodily discomfort. Serious adverse events were more common with neurostimulation than with medication alone (13 percent vs. 4 percent, P<0.04) and included a fatal intracerebral hemorrhage. The overall frequency of adverse events was higher in the medication group (64 percent vs. 50 percent, P=0.08).
In this six-month study of patients under 75 years of age with severe motor complications of Parkinson's disease, neurostimulation of the subthalamic nucleus was more effective than medical management alone. (ClinicalTrials.gov number, NCT00196911 [ClinicalTrials.gov].).
Of identity and diversity
- locke