Revisión de los procedimientos intervencionistas neurolíticos en el dolor asociado al cáncer de páncreas. Propuesta de algoritmo / Neurolytic procedures for pancreatic cáncer pain: a systematic review and a proposal for an algorithm treatment

El cáncer de páncreas produce dolor en más del 80 % de los pacientes, con un manejo analgésico en ocasiones insatisfactorio debido a las opciones terapéuticas limitadas y a la variación de la práctica clínica, siendo necesario un manejo multidisciplinar. El desarrollo de este artículo ha consistido en revisar la literatura y resumir la evidencia actual de los procedimientos intervencionistas neurolíticos para manejar el dolor visceral asociado al cáncer de páncreas. La fuente de artículos de esta revisión se ha obtenido a través de PubMed y Medline, limitando la búsqueda a ensayos controlados y aleatorizados, revisiones sistematizadas, estudios prospectivos y retrospectivos y presentaciones de series de casos. Se muestra la evidencia actual de los diferentes abordajes para la neurólisis del plexo celiaco y de los nervios esplácnicos, describiendo su eficacia, riesgos, complicaciones y limitaciones. El objetivo final ha sido establecer una propuesta de algoritmo intervencionista que pueda mejorar el manejo del dolor en los pacientes que sufren dolor visceral debido al cáncer de páncreas

Pancreatic cancer provokes pain in more than 80 % of patients, resulting in a management of pain that is often unsatisfactory due to the limited treatment options and the significant variation in clinical practice, emphasizing the need for a multidisciplinary approach. This article has been redacted to review the literature and summarize the actual evidence of neurolytic procedures to treat pain caused by pancreatic cancer. The sources of these of articles have been obtained by using PubMed and Medline, restricting the search to randomized control comparative studies, systematic reviews, prospective and retrospective studies, and case series presentations. This article shows the actual evidence of the different approaches for the celiac plexus and splanchnic nerve neurolysis, regarding its efficacy, risks, adverse effects, and limitations. The final objective has been to propose an interventional algorithm that might help to improve pain management in patients suffering from pancreatic cancer

Dolor irruptivo oncológico en el anciano / Breakthrough cancer pain in the elderly

El dolor irruptivo se define como una exacerbación aguda del dolor de rápida aparición, corta duración y de intensidad moderada o elevada, que ocurre de forma espontánea o en relación con un evento predecible o no predecible a pesar de existir un dolor basal estabilizado y controlado. Sin embargo, existen dudas sobre la definición, terminología, epidemiología y valoración del dolor irruptivo sin una clara contestación y consenso, especialmente en la población anciana. En esta revisión no sistematizada se intentarán sintetizar y resumir los aspectos más relevantes del dolor irruptivo en los ancianos en base a las escasas publicaciones existentes en dicho grupo poblacional (AU)

Breakthrough pain is defined as an acute exacerbation of pain with rapid onset, short duration and moderate or high intensity, which occurs spontaneously or in connection with a predictable or unpredictable event despite there being stabilised and controlled baseline pain. However, there are doubts about the definition, terminology, epidemiology, and assessment of breakthrough pain, with no clear answers or consensus, especially in the elderly population. This non-systematic review summarises the most important aspects of breakthrough pain in the elderly, based on the limited publications there are in that population group (AU)

Percutaneous CT-Guided Sympathicolysis with Radiofrequency for the Treatment of Palmar Hyperhidrosis.

PURPOSE: To evaluate the benefits of computed tomography (CT)-guided percutaneous sympathicolysis with radiofrequency in patients with primary palmar hyperhidrosis (PPHH) in terms of safety, patient satisfaction, and short- and long-term efficacy. MATERIALS AND METHODS: A total of 139 procedures in 108 patients (mean age, 29.89 y ± 10.94), including 50 men and 58 women, with PPHH and therapy-resistance of nonsurgical treatments were retrospectively analyzed. Treatment was performed bilaterally at T2, T3, and T4 levels, reaching 90°C during 8 minutes. Technical success, immediate efficacy, and presence of complications were analyzed. For follow-up, the Hyperhidrosis Disease Severity Scale was used to evaluate the hyperhidrosis before, at one month, and in the long-term through a survey of 42 patients. Patients' satisfaction and complications were also recorded. RESULTS: The technical success rate was 98.56%. The increase in palmar skin temperature was 4.88°C ± 1.85. A total of 85.3% of participants had completely dry hands immediately after treatment. The mean follow-up time was 41.34 months (range, 6-62 mo). One month after treatment, the response rate was 77.38% (P < .001). At long-term follow-up, the response rate was 69.04% (P < .001). Two major complications were observed (1.8%), 52.38% of patients were satisfied, and 59.52% of patients presented compensatory hyperhidrosis at long-term follow-up. CONCLUSIONS: Percutaneous CT-guided sympathicolysis is a safe and effective technique for the treatment of PPHH and can be considered as a second choice in patients in whom other nonsurgical therapeutic options have failed, despite the compensatory hyperhidrosis rates.

[Breakthrough cancer pain in the elderly]. / Dolor irruptivo oncológico en el anciano.

Breakthrough pain is defined as an acute exacerbation of pain with rapid onset, short duration and moderate or high intensity, which occurs spontaneously or in connection with a predictable or unpredictable event despite there being stabilised and controlled baseline pain. However, there are doubts about the definition, terminology, epidemiology, and assessment of breakthrough pain, with no clear answers or consensus, especially in the elderly population. This non-systematic review summarises the most important aspects of breakthrough pain in the elderly, based on the limited publications there are in that population group.

Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief.

PURPOSE: Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a "strip lesion" to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. METHODS: The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. RESULTS: There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m(-1)) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. CONCLUSIONS: The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of thermal damage zone dimension.

Cultural adaptation and validation of the painDETECT scale into Spanish.

OBJECTIVE: The aim of this study was to culturally adapt into Spanish and validate the painDETECT questionnaire, a brief self-administered instrument designed to screen the presence of a neuropathic pain component in usual clinical practice. METHODS: The original English painDETECT questionnaire was culturally adapted into Spanish (Spain) by 2 independent translators under supervision of an expert panel. The LANNS, and a pain visual analog scale were administered along with the painDETECT questionnaire to a sample of 252 patients with neuropathic, nociceptive, or mixed pain for at least 3 months. Patients were classified by experienced specialists under normal conditions of clinical practice. A retest measure after 24 to 48 hours was also carried out. Reliability, construct validity, convergent validity, criterion, and discriminant validity were assessed. RESULTS: An effective sample of 221 patients with chronic pain was recruited, 32% diagnosed of neuropathic origin, 32% of nociceptive, and remaining 36% presented mixed pain. The average age was 57.8 years (SD=14.2) and 59% were women. Cronbach alpha attained a value of 0.86, and the intraclass correlation coefficient with the retest was 0.93. The factor structure was coherent with the one informed for the original instrument. Pearson correlation with the LANSS scale was 0.88. Area under the receiver operating characteristic curve was 0.88 when comparing neuropathic and nociceptive groups. Using the suggested cutoff value for pain presence of 19 points or higher, the following discriminant values are obtained: sensitivity=75%, specificity=84%, Youden Index=0.595, positive predictive value=92%, and negative predictive value=60%. The absence cutoff value of 12 points or bellow raised the following values: sensitivity=93%, specificity=68%, Youden Index=0.61, positive predictive value=87%, and negative predictive value=80%. When mixed pain patients are included in the group with a neuropathic component, discriminant values are slightly reduced, as expected. CONCLUSIONS: The culturally adapted version of the painDETECT presents good psychometric properties and shows to be a valid patient-reported outcome for measuring the presence of a neuropathic component in patients with chronic pain.

Prospective study of percutaneous radiofrequency sympathicolysis in severe hyperhidrosis and facial blushing: efficacy and safety findings.

OBJECTIVE: Hyperhidrosis (Hh) and facial blushing (Fb) are conditions caused by hyperactivity of the sympathetic system; they affect around 2% of the population. Severe cases have been typically treated with thoracic sympathectomy through a minimally invasive approach. We sought to determine if severe Hh and/or Fb patients, who are reluctant to go through an operation with general anaesthesia, could benefit from receiving percutaneous radiofrequency ablation of the sympathetic chain. METHODS: Prospectively collected data obtained from May 2007 to May 2010 were analysed to compare the treatment efficacy and effects on quality of life of the two procedures. RESULTS: From a total of 58 patients enrolled in the study, 31 were treated with radiofrequency procedures, whereas 27 received surgical sympathectomy. Patients with Hh had better results with surgery than with radiofrequency sympathicolysis in terms of efficacy (p=0.0001) and quality of life (p=0.0002). However, there was still a significant improvement in quality of life in the group of patients treated with radiofrequency sympathicolysis (p=0.004). Patients with Fb had good results with surgical procedures and poor outcomes with radiofrequency ablation, resulting in significant differences in treatment efficacy (p=0.005) and in quality of life (p=0.003). Fb patients treated with radiofrequency procedures had no improvement in quality of life after the intervention (p=0.28). CONCLUSION: Our results support the view of surgical sympathectomy as the gold-standard treatment in severe cases of Hh and Fb. Radiofrequency sympathicolysis is useful as a second-treatment choice for Hh patients. Fb patients do not benefit from radiofrequency sympathicolysis.

Peripheral nerve stimulation: definition.

Recently, there has been a tremendous evolution in the field of neurostimulation, both from the technological point of view and from development of the new and different indications. In some areas, such as peripheral nerve stimulation, there has been a boom in recent years due to the variations in the surgical technique and the improved results documented by in multiple published papers. All this makes imperative the need to classify and define the different types of stimulation that are used today. The confusion arises when attempting to describe peripheral nerve stimulation and subcutaneous stimulation. Peripheral nerve stimulation, in its pure definition, involves implanting a lead on a nerve, with the aim to produce paresthesia along the entire trajectory of the stimulated nerve.

Electric parameters optimization in spinal cord stimulation. Study in conventional nonrechargeable systems.

BACKGROUND: Spinal cord stimulation devices provide a means of creating an electric field. The parameters used to produce this electric field are: pulse amplitude, pulse width (Pw), and pulse frequency (F). AIMS: The purpose is to document the effects that the various stimulus parameters have on patient perception of paresthesia and the relationship that this perception has on pain relief. METHODS: Stimulus parameters were varied independently keeping the electrode polarity constant while recording stimulation thresholds. The Pw was varied from 195 to 300 µ sec while maintaining the frequency at 50 Hz. The F was varied from 10 to 100 Hz while maintaining the Pw at 300 µ sec. We also measured the paresthesia coverage percentage and the subjective perception of quality reported by the patients with each one of the parameter changes. RESULTS: There was a statistically significant correlation between Pw and all the stimulation thresholds. As for the therapeutic range, the differences observed also were statistically significant. Pw variation did not produce significant differences in coverage and subjective quality of the paresthesia. The perception threshold did not vary significantly with F changes. However, F significantly affected both coverage of the painful area and paresthesia perception quality. CONCLUSIONS: In the usual Pw ranges, it seems that its usefulness is limited to obtaining finer adjustments in the stimulation amplitude. Frequency management may be significantly useful to get a wider coverage of the stimulated area.