Estimulação de alta frequência do núcleo subtalâmico para o tratamento da doença de Parkinson - uma perspectiva de equipe

High-Frequency Stimulation of the Subthalamic Nucleus for the Treatment of Parkinson's Disease - A Team Perspective
Manjit K. Sanghera; J. Michael Desaloms; R. Malcolm Stewart

DISCLOSURES J Neurosci Nurs. 2004;36(6):301-311.

Abstract and Introduction
Parkinson's disease (PD) is a debilitating neuro degenerative disorder affecting more than 1.2 million people in the United States. Genetic and environmental toxins are believed to be risk factors in acquiring the disease. PD is characterized by tremors, rigidity, bradykinesia, poor gait, and postural instability. These cardinal symptoms improve with medication such a levo-dopa (L-dopa). However, over time, as the disease progresses, the patient becomes refractory to medication, or medication produces debilitating side effects. When this occurs or when there are worsening of symptoms, neurosurgical treatment is recommended, particularly deep brain stimulating (DBS) electrodes implanted in the subcortical subthalamic nucleus (STN). Over the last 5 years STN DBS has gained acceptance and become the neurosurgical treatment of choice for PD. To achieve maximum beneficial effects with minimum adverse effects from the surgery, the expertise of an integrated team of physicians and nurses is essential. A clear understanding of the different aspects of the procedure,including the risks and benefits of the treatment, assists neuroscience nurses in communicating with the PD patient, and providing the most appropriate,knowledge-based pre- and postoperative care.

Parkinson's disease (PD) is a neurodegenerative disorder affecting over 1.2 million people in the United States. Most patients are older than 50 years, but 10% are younger than 50. The etiology of PD is multifactorial with genetic and environmental factors combining to reduce dopamine levels in the basal ganglia (Baldereschi etal., 2003; Gasser, 2001; Scott et al., 2001; Tsang & Soong, 2003). The disease is characterized by tremors, rigidity, bradykinesia, postural instability, and gait disability. Some of these cardinal symptoms can be improved by medication such a levo-dopa (L-dopa). However, as the disease progresses, the medication becomes less effective or produces debilitating side effects. The failure of medical therapy to provide long-lasting relief of symptoms, along with improvement in neuro imaging and neurosurgical stereotactic technique, has prompted a resurgence in the surgical approaches for the treatment of PD. One neurosurgical treatment for PD involves high-frequency stimulation of the subthalamic nucleus (STN). This is achieved through a deep brain stimulating (DBS) electrode implanted in the STN, a small structure (10 x 10.7 x 7 mm; Bejjani et al., 2000) buried deep in the subcortex.

This neurosurgical procedure is gaining increasing acceptance. Significant improvement in motor symptoms is reported, as well as a significant reduction in dopaminergic medication with a consequent improvement or elimination of L-dopainduced dyskinesias (Krack et al., 2003). As this cost-effective and reversible procedure becomes the standard neurosurgical treatment of choice for PD, nurses play a pivotal role in the management of pre- and postoperative care of PD patients.

This article reviews the preoperative and immediate postoperative aspects of STN DBS and reports on our experiences with this technique. Seventy-eight DBS STN surgeries (i.e., 48 simultaneous bilateral, 22 staged bilateral, and 8 unilateral) were performed at Presbyterian Hospital of Dallas (PHD) with no mortality and no long-term morbidity. Nearly all patients have had their united PD rating scale (UPDRS) lowered by an average 30%; the medication has been reduced by 30%-60%; and four patients are completely off medication. The long-term effects of DBS for motor symptoms continue to be positive, but the progression of the nonmotor symptoms, particularly behavioral ones, continues over time.

The degree of benefit obtained is critically dependent on a number of factors such as (a) selecting the ideal patient, (b) timing the surgery, (c) precisely localizing and implanting a DBS electrode at the target site, (d) programming the stimulator to alleviate motor symptoms while reducing adverse effects of stimulation, and (e) providing appropriate postoperative care. By careful optimization of all these variables attained by the interaction of a team comprising a neurosurgeon, neurologist, neurophysiologist, anesthesiologist, operating room nurses, nurse practitioners,and outpatient nurses, it is possible to obtain excellent outcomes with few to no immediate adverse effects. (segue...) Fonte: MedScape.