Estimulación de la médula espinal: más allá del manejo del dolor / Spinal cord stimulation: Beyond pain management

Introducción: La descripción de la teoría de la compuerta del dolor fue el punto de partida para el desarrollo de la estimulación de la médula espinal (EME). El presente artículo describe las indicaciones para el tratamiento del dolor y otros usos no relacionados con este. Desarrollo: En la actualidad existen diversos paradigmas de EME: tónica, de alta frecuencia en ráfaga o simplemente de alta frecuencia. Estas se distinguen por la presencia de parestesias. La EME ha mostrado beneficio sobre todo en dolor de tipo neuropático. El síndrome de cirugía espinal fallida muestra las mejores tasas de respuesta, aunque en casos de síndrome doloroso regional complejo y neuropatía diabética, así como de radiculopatía y lumbago sin cirugía espinal previa, también se logra una reducción importante del dolor. Aunque su aplicación en el dolor de tipo fantasma y en el asociado a enfermedad vascular periférica o cardiovascular parece útil, no existe una evidencia sólida para generalizar su empleo. Por otra parte, la EME también reduce el dolor neuropático secundario a tumor, a pesar de que esta línea ha sido poco explorada. Otras indicaciones no relacionadas con el dolor son trastornos de movimiento, espasticidad y secuelas de trauma medular. Sin embargo, el uso de la EME se ve limitado por dos factores principales: las complicaciones mecánicas y el costo de la terapia. Conclusión: Durante los 50 años de aplicación, la EME ha mostrado grandes avances. Asimismo, a medida que se perfeccione el hardware y el software relacionados con esta, se podrá mejorar la efectividad y reducir el rango de complicaciones. La indicación para la EME se podría extender a otras enfermedades y su uso se expandiría si, además, se lograra diseñar una tecnología asequible. (AU)

Introduction: The gate control theory of pain was the starting point of the development of spinal cord stimulation (SCS). We describe the indications for the treatment in pain management and other uses not related to pain. Development: There are currently several paradigms for SCS: tonic, burst, and high frequency. The main difference lies in the presence of paraesthesias. SCS is most beneficial for treating neuropathic pain. Patients with failed back surgery syndrome show the best response rates, although a considerable reduction in pain is also observed in patients with complex regional pain syndrome, diabetic neuropathy, radiculopathy, and low back pain without previous surgery. Phantom pain or pain related to cardiovascular or peripheral vascular disease may improve, although there is a lack of robust evidence supporting generalisation of its use. SCS also improves cancer-related pain, although research on this issue is scarce. Non-pain-related indications for SCS are movement disorders, spasticity, and sequelae of spinal cord injury. The main limiting factors for the use of SCS are mechanical complications and the cost of the treatment. Conclusion: In its 50-year history, SCS has progressed enormously. The perfection of hardware and software may improve its effectiveness and reduce the rate of complications. Indications for SCS could include other diseases, and its use could be expanded, if the costs of the technology are reduced. (AU)

Spinal cord stimulation: Beyond pain management. / Estimulación de la médula espinal: más allá del manejo del dolor.

INTRODUCTION: The gate control theory of pain was the starting point of the development of spinal cord stimulation (SCS). We describe the indications for the treatment in pain management and other uses not related to pain. DEVELOPMENT: There are currently several paradigms for SCS: tonic, burst, and high frequency. The main difference lies in the presence of paraesthesias. SCS is most beneficial for treating neuropathic pain. Patients with failed back surgery syndrome show the best response rates, although a considerable reduction in pain is also observed in patients with complex regional pain syndrome, diabetic neuropathy, radiculopathy, and low back pain without previous surgery. Phantom pain or pain related to cardiovascular or peripheral vascular disease may improve, although there is a lack of robust evidence supporting generalisation of its use. SCS also improves cancer-related pain, although research on this issue is scarce. Non-pain-related indications for SCS are movement disorders, spasticity, and sequelae of spinal cord injury. The main limiting factors for the use of SCS are mechanical complications and the cost of the treatment. CONCLUSION: In its 50-year history, SCS has progressed enormously. The perfection of hardware and software may improve its effectiveness and reduce the rate of complications. Indications for SCS could include other diseases, and its use could be expanded, if the costs of the technology are reduced.

Assessment of systemic cellular inflammatory response after spontaneous intracerebral hemorrhage.

OBJECTIVE: After spontaneous intracerebral hemorrhage (ICH) a local and systemic inflammatory response is activated. Interleukin-6 (IL) is one of most relevant orchestrators of inflammatory responses in the brain and is released from multiple immune cells, including neutrophils. Herby we assessed the relevance of systemic inflammation in patients suffering ICH. METHODS: From October 2010 to October 2011 we included in our routine of laboratory investigations besides to C-reactive protein (CRP), the addition of IL-6 and an analysis of the subpopulation of circulating blood cells. Values at admission, at 3rd and 7th day after admission were evaluated. We analyzed 43 patients with non-traumatic ICH; stroke-related ICH or tumor associated hemorrhage were excluded. Outcome variables were 30 and 90-day mortality and NIHSS at discharge. A natural logarithmic transformation of IL-6, lymphocytes, and monocytes was used. RESULTS: 8.6% died within 30-days and mortality increased to 39.5% at 90th day. Total leukocytes and neutrophils as well as IL-6 at admission were statistically significant increased among patients who died within 30days after ICH onset (p=0.002). IL-6 and CRP in follow-up (3rd and 7th day) were higher among patients with poor outcome (NIHSS >15). The number of circulating lymphocytes and monocytes was not different in measurement. Leukocytes and neutrophils at 3rd day after admission were augmented in patients with respiratory infection and CRP in follow-up increased if some kind of infection was clinically or microbiologically detected. IL-6 at admission and in follow-up and monocytes at 7th day were related to ICH volume. CRP-values at 3rd or 7th day but not at admission were associated to bigger ICH-volume. The values of IL-6 were highly correlated to 30-day mortality and volume of ICH as CRP only with ICH volume. CONCLUSION: After ICH onset a systemic activation of immune system seems to be induced and may be influencing outcome. Peripheral recruitment of leukocytes, especially neutrophils could be a target for future therapeutic interventions. Because of the tighter correlation of IL-6 at admission, it might be more accurate for prognostic issues than CRP.

Effect of increased glucose levels on short-term outcome in hypertensive spontaneous intracerebral hemorrhage.

OBJECTIVE: Spontaneous intracerebral hemorrhage (ICH) can be a devastating event. Increased glucose levels in the plasma may be related to poor outcomes; however, the precise association remains unclear. METHODS: We retrospectively assessed 116 patients with hypertensive ICH. Glucose level in the plasma was assessed at days 0, 1, and 3. Outcome variables were mortality within 7 and 30days and the National Institutes of Health Stroke Scale (NIHSS) score at day 14 after ICH onset. RESULTS: Twenty deaths had occurred by day 7, and the 30-day mortality rate was 31.9%. Hyperglycemia at day 0 was significantly more common in patients who died within 7days or 30days. Hyperglycemia at day 1 was more common in patients with an NIHSS score >15 on admission and at day 14. No differences in glucose levels were found between diabetic and non-diabetic patients. Among non-diabetic patients, higher glucose levels were related to poorer outcomes (death or an NIHSS score >15). In multivariate analysis, glucose levels >140mg/dL at day 1 were related to the 30-day mortality (hazard ratio=2.65; 95% confidence interval [CI]=1.15-6.12, p=0.02), and glucose levels >160mg/dL at day 1 were associated with an NIHSS score >15 at day 14 (odds ratio=3.08; 95% CI=0.9-10.5, p=0.07). White blood cell counts were directly associated with poorer outcomes and significantly correlated to glucose levels. CONCLUSION: Initially increased glucose levels and increased levels within 24h of ICH onset were related to poorer outcomes. Altered glucose metabolism may be due to inflammatory cell activation. Further studies are needed to clarify the association between immune activation and glucose metabolism after ICH onset.

Continued statin therapy could improve the outcome after spontaneous intracerebral hemorrhage.

Spontaneous intracerebral hemorrhage (ICH) often represents a devastating event despite maximal therapeutic efforts. Statins are drugs primarily used as cholesterol reducers with several pleiotropic effects that may result in neuroprotection. In this study, we assessed the continued use of statins after acute ICH. From January 2008 to October 2010, we analyzed a retrospective cohort of 178 patients with acute ICH. Patients with head injury, cerebral tumors, hemorrhage after ischemic stroke, and having a National Institute Health Stroke Scale (NIHSS) score of greater than 30 points on admission were excluded. In 29 patients, statins were continued within the first 24 h after onset of ICH and, subsequently, given daily until discharge, whereas 149 nonusers were used as controls. Inpatient mortality, NIHSS, and Glasgow Outcome Score (GOS) at discharge as well as mortality after 10 days, 3 months, and 6 months were recorded as outcomes. Additionally, changes of C-reactive protein (CRP) and white blood cell (WBC) counts, as well as aspartate transaminase and alanine transaminase levels were assessed. Except for the number of hypertensive and diabetic patients, characteristics on admission were similar between both groups. No mortality was observed in statin users, whereas 19 controls (12.7 %) died (p = 0.04) until discharge; after 10 days, 3 months, and 6 months, a similar trend was found. After 6 months, statin use was associated to lower mortality in regression models (OR = 0.32, 95 % CI = 0.11-0.95, p = 0.04). In the same way, statin use was related to NIHSS reduction (-3.53, 95 % CI = -7.59 to 0.42, p = 0.07). In mixed models, changes of WBC counts and CRP levels were associated with statin use. The hepatic enzymes were similar between groups. The continued use of statins after ICH could be associated to early neurological improvement and may reduce mortality within 6 months. Immunomodulation as a pleiotropic effect of statins may represent one of the underlying mechanisms.