Manual scoring of periodic limb movements in children: is it still necessary?

OBJECTIVE: Although manual scoring has been classically considered the gold standard to identify periodic leg movements (PLM), it is a very time consuming and expensive process, also subject to variability in interpretation. In the last decades, different authors have observed reasonably good agreement between automated PSG scoring algorithms and manual scoring in adults, according to established criteria. We aim to compare the automatic software analysis of our polysomnogram with the manual staging in children with sleep-disordered breathing. METHODS: We performed a semiautomatic method, in which an experienced technician watched the video recording and removed from the automatic analysis those movements that did not correspond to true candidate leg movement (LM). RESULTS: A total of 131 PSGs were studied; applying the established criteria, 65 children were diagnosed of obstructive sleep apnea, and 66 presented snoring but with no sleep apnea. The mean age was 6.7 years (±1.7) and twenty-five children (19.08 %) had a PLMI >5/h. Statistical differences were found not only for PLMI (manual: 2.20 (0.7, 4.1) vs automatic (6.4 (3.85,9.5); p < 0.001), but for almost of all indexes assessed between the automatic and the manual scoring analysis. The level of concordance was only moderate for PLM index (0.63 [0.51-0.72]); showing that, unlike the articles published in the adult population, automatic analysis is not accurate in children and, manually or semi-automatically analysis as ours need to be done. CONCLUSION: It seems that PLM detection algorithm might work accurately but, the real need would be a true LM detection algorithm.

Duchenne and Becker muscular dystrophy: Cellular mechanisms, image analysis, and computational models: A review.

The muscle is the principal tissue that is capable to transform potential energy into kinetic energy. This process is due to the transformation of chemical energy into mechanical energy to enhance the movements and all the daily activities. However, muscular tissues can be affected by some pathologies associated with genetic alterations that affect the expression of proteins. As the muscle is a highly organized structure in which most of the signaling pathways and proteins are related to one another, pathologies may overlap. Duchenne muscular dystrophy (DMD) is one of the most severe muscle pathologies triggering degeneration and muscle necrosis. Several mathematical models have been developed to predict muscle response to different scenarios and pathologies. The aim of this review is to describe DMD and Becker muscular dystrophy in terms of cellular behavior and molecular disorders and to present an overview of the computational models implemented to understand muscle behavior with the aim of improving regenerative therapy.

Simulation of the electrical stimulation of the rat brain using sleep frequencies: A finite element modeling approach.

A realistic rat brain model was used to simulate current density and electric field distributions under frequencies characteristic of sleeping states (0.8, 5, and 12 Hz). Two anode-electrode setups were simulated: plate vs. screws-anode, both with a cephalic cathode. Our simulations showed that these frequencies have limited impact on electric field and current density; however, the highest frequency evidenced higher values for both variables. The type of electrode setup had a greater effect on current distribution and induced fields. In that sense, the screws setup resulted in higher values of the modeled variables. The numeric results obtained are within the range of available data for rodent models using the finite elements method. These modeled effects should be analyzed regarding anatomical consequences (depth of penetration of the currents) and purpose of the experiment (i.e., entrainment of brain oscillations) in the context of sleep research.

Numerical approximation to the effects of the atmospheric stability conditions on the dispersion of pollutants over flat areas.

Using the Computational Fluid Dynamics technique (CFD), we explored the effects of the atmospheric stability conditions on the dispersion of solid and gas-phase pollutants emitted from an area source located on a flat region. As an application, the dispersion of pollutants emitted from roads located on flat terrains was considered. Toward that end, we set up a model that describes the dispersion of air pollutants in a small region (< 1 km long) near the ground surface (< 250 m high). It consists of a neutrally stratified model modified to account for the atmospheric stability effects by imposing the near-ground stratification through the Monin-Obukhov similarity theory and the k-ε turbulence model adjusted for each atmospheric stability condition. Using this model, we simulated the dispersion of pollutants emitted from the road and plotted the resulting downwind concentrations in terms of dimensionless numbers. Results from our CFD-based model were highly correlated (R2 > 0.95) with the SF6 concentrations measured downwind a line source of this trace gas by the U.S. National Oceanic Atmospheric Administration in 2008 under different conditions of atmospheric stability. Numerical and experimental results showed that, under any of the stability conditions explored, the near-road pollutant concentrations are highly correlated (R2 > 0.87) to the concentrations observed under neutral conditions. When the atmosphere is extremely stable, those concentrations were up to 12 times higher than those observed under neutral conditions. We report the constant of proportionality obtained for every stability condition.

Caracterización de la complejidad de medicamentos en un grupo de pacientes asmáticos de difícil control / Characterization of medication complexity in a group of non-controlled asthmatic patients

Introducción: El asma es una enfermedad respiratoria que impacta mayormente a pacientes con descontrol sintomático, dado el mayor riesgo de exacerbaciones. Este riesgo se incrementa por falta de adherencia, que puede favorecerse con regímenes terapéuticos complejos. Este estudio revisa la relación entre adherencia y complejidad terapéutica en un grupo de pacientes asmáticos de díficil control. Método: Este es un estudio prospectivo, que incluyó pacientes asmáticos de difícil control atendidos en la Clínica Aire del Hospital San Juan de Dios, de la Caja Costarricense de Seguro Social, en Costa Rica. La complejidad de las terapias se determino mediante el Índice de Complejidad del Régimen de Medicamentos (MRCI, por sus siglas en inglés) y la adherencia se midió utilizando la prueba de Morisky-Green-Levine. El análisis se basó en estadística descriptiva y para las relaciones se utilizaron las pruebas T student pareado e índice de Pearson. Resultados: Se incluyó 22 pacientes en este estudio. Estos fueron mayoritariamente mujeres con una edad promedio de 50,5 años (DE 15,3), quienes utilizaron un promedio de 4,2 (DE 1,2) medicamentos e inicialmente solo el 36,4% (n = 8) resultó adherente al tratamiento. La estrategia terapéutica más utilizada combinó el corticoesteroide inhalado, el beta-agonista de acción prolongada y el inhibidor de leucotrienos (45,5%, n = 10). El valor promedio del MRCI fue 20,0 (DE 5,57), dado principalmente por la diversidad de formas farmacéuticas y de frecuencias de administración. Se observo una tendencia no estadísticamente significativa de mayor adherencia conforme aumento la complejidad (Indice de Pearson 0,338). Conclusiones: En el presente estudio los regímenes terapéuticos fueron de complejidad alta asociados a una baja adherencia al tratamiento. Esto sugiere que los pacientes asmáticos no controlados, son una población prioritaria para incluirse en programas que favorezcan adherencia.(AU)

Introduction: Asthma is a respiratory disease that impacts mainly on non-controlled patients due to a higher risk of exacerbations. This risk is increased by patients’ lack of adherence and the complexity of therapeutic regimens. This study reviews the relationship between adherence and therapeutic complexity in a group of difficult-to-control asthmatic patients. Method: It was done a prospective study which included non-controlled asthmatic patients who were being looked after at Clinica Aire in the San Juan de Dios Hospital, part of the Caja Costarricense de Seguro Social, in Costa Rica. Complexity was determined using the Medication Regimen Complexity Index (MRCI) whereas adherence was measured using the Morisky-Green-Levine test. For the statistical analysis, descriptive statistical methods were used and the relationship between the variables was probed using Student ́s T tests and the Pearson's index.Results:A total of 22 patients were included in this study. They were mainly women with an average age of 50.5 years (SD 15.3), who used an average of 4.2 (SD 1.2) medications, with only 36.4% (n = 8) reporting adherence to treatment at the beginning of the study. The most widely used treatment strategy was the combination of inhaled corticosteroid, long-acting beta-agonist, and a leukotriene inhibitor (45.5%, n = 10). The average value of the MRCI was 20 (SD: 5.57), affected mainly by the diversity of pharmaceutical forms and frequency of administration. A non-statistically significant trend of greater adherence was observed as complexity increased (Pearson index 0.338). Conclusions: The high complexity therapeutic regimens observed in this study were associated with low adherence to treatment. This suggests that non-controlled asthmatic patients are critical population to be included in programs...(AU)

Distances of transmission risk of COVID-19 inside dwellings and evaluation of the effectiveness of reciprocal proximity warning sounds.

One of the main modes of transmission and propagation of COVID-19 (SARS-CoV-2) is the direct contact with respiratory droplets transmitted among individuals at a certain distance. There are indoor spaces, such as dwellings, in which the transmission risk is high. This research aims to record and analyze risk close contacts in this scope, experimentally assessing the effectiveness of using electronic proximity warning sound devices or systems. For this purpose, the methodology is based on monitoring the location of the occupants of a dwelling. Then, the days in which a proximity warning sound system is installed and activated are compared to the days in which the system is not activated. The results stressed the significant reduction of time and number of close contacts among individuals when the warning was activated. Regarding the relation between the number and the duration of close contacts, together with the reductions mentioned, the possibility of making certain predictions based on the distributions obtained is proved. All this contributes to the progress in the prevention of COVID-19 transmission because of close contacts in dwellings.

Psychological well-being among older adults during the COVID-19 outbreak: a comparative study of the young-old and the old-old adults.

The COVID-19 outbreak could be considered as an uncontrollable stressful life event. Lockdown measures have provoked a disruption of daily life with a great impact over older adults' health and well-being. Nevertheless, eudaimonic well-being plays a protective role in confronting adverse circumstances, such as the COVID-19 situation. This study aims to assess the association between age and psychological well-being (personal growth and purpose in life). Young-old (60-70 years) and old-old (71-80 years) community-dwelling Spaniards (N = 878) completed a survey and reported on their sociodemographic characteristics and their levels of health, COVID-19 stress-related, appraisal, and personal resources. Old-old did not evidence poorer psychological well-being than young-old. Age has only a negative impact on personal growth. The results also suggest that the nature of the COVID-19 impact (except for the loss of a loved one) may not be as relevant for the older adults' well-being as their appraisals and personal resources for managing COVID-related problems. In addition, these results suggest that some sociodemographic and health-related variables have an impact on older adults' well-being. Thus, perceived-health, family functioning, resilience, gratitude, and acceptance had significant associations with both personal growth and purpose in life. Efforts to address older adults' psychological well-being focusing on older adults' personal resources should be considered.

Differential IL 10 serum production between an arm-based and a leg-based maximal resistance test.

Bench press (i.e. arm-based) and half-squat (i.e. leg-based) are exercises commonly used to increase and evaluate muscular strength. In addition to differences in the location of the muscles that participate in each exercise, the total muscle mass required for the latter is larger than that involved in the former. The aim of this study is to analyze the effects of a maximal incremental strength test when performed by bench press and by half-squat on myocellular damage, oxidative damage and the inflammatory cytokine response. Ten male athletes were subjected to half-squat and bench press incremental strength tests. Blood samples were collected at rest, 15-minutes and 24 h post-test. Hydroperoxide and malondialdehyde concentrations were determined as lipid peroxidation markers. Lactate dehydrogenase (LDH) and creatine kinase isoenzyme MB (CK-MB) activities were determined as markers of muscle damage. α-Actin concentration was determined as a marker of sarcomeric damage. Serum interleukin (IL) 6, IL10, and tumor necrosis factor alpha (TNFα) were determined to assess the inflammatory response. LDH and CK-MB values were greater at 15 min and 24 h post bench press exercise (p < 0.05). No differences were found in lipid peroxidation or α-actin. Interestingly, IL10 values were greater in response to the press bench at 24 h post-test (p < 0.05). Our results suggest that, at equivalent workloads, an arm-based exercise induced higher anti-inflammatory effects and more severe muscle damage compared with a leg-based exercise.

Comparison of the inflammatory and stress response between sprint interval swimming and running.

The aim of the study was to compare myocellular damage, metabolic stress, and inflammatory responses as well as circulating sodium (Na+ ) and potassium (K+ ) between a single sprint swimming and running training. Eighteen subjects regularly involved in swimming and running training for at least 2 years were recruited. The subjects performed 8 × 30 seconds "all out" exercise on different days either by running or by swimming in a random order. Blood was collected before each training session, after the cessation of exercise (post) and after 2 hours of rest (2 hours). We then analyzed tumor necrosis factor alpha (TNF-α), interleukin 10 (IL-10), interleukin 6 (IL-6), cortisol, creatine kinase MB isoform (CK-MB), lactate dehydrogenase (LDH), K+ , and Na+ . Neither TNF-α nor IL-10 differed between swimming and running. Most of the subjects showed a non-statistically significant increase of LDH and CK-MB after swimming. On the other hand, IL-6 (P < .05) and cortisol (P < .05) were significantly lower after 2 hours of swimming than after running. In addition, post-exercise K+ was significantly lower (P < .001) for swimming than for running. Our results provide evidence of similar inflammatory responses between exercise modes but lower metabolic stress in response to swimming than in response to running.

Human enteric viruses in a wastewater treatment plant: evaluation of activated sludge combined with UV disinfection process reveals different removal performances for viruses with different features.

This study assess the quality of wastewater through the detection and quantification of important viruses causing gastroenteritis at different stages of the wastewater treatment process in an activated-sludge wastewater treatment plant with ultraviolet disinfection. Ten sampling events were carried out in a campaign along a period of 18 months collecting wastewater samples from the influent, after the activated-sludge treatment, and after the final disinfection with UV radiation. Samples were concentrated through ultracentrifugation and analysed using retro-transcription, PCR and real time quantitative PCR protocols, for detection and quantification of Group A Rotavirus (RVA), Human Astrovirus (HAstV), Norovirus Genogroup II (NoV GII) and Human Adenovirus (HAdV). HAdV (100%), NoV GII (90%), RVA (70%) and HAstV (60%) were detected in influent samples with concentration from 1·4 (NoV GII) to 8·0 (RVA) log10  gc l-1 . Activated-sludge treatment reached well quality effluents with low organic material concentration, although nonstatistical significant differences were registered among influent and postactivated sludge treatment samples, regarding the presence and concentration for most viruses. All post-UV samples were negative for NoV GII and HAstV, although RVA and HAdV were detected in 38% and 63% of those samples respectively, with concentration ranging from 2·2 to 5·5 and 3·1 to 3·4 log10  gc l-1 . SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that an activated-sludge wastewater treatment plant with UV disinfection reduces to levels below the detection limit those single-stranded RNA viruses as noroviruses and astroviruses and reach significant lower levels of rotaviruses and adenoviruses after the complete treatment process.

Antioxidant effect of exercise: Exploring the role of the mitochondrial complex I superassembly.

Mitochondrial respiratory complexes become assembled into supercomplexes (SC) under physiological conditions. One of the functional roles of these entities is the limitation of reactive oxygen species (ROS) produced by complex I (CI) of the respiratory chain. We sought to determine whether the systemic antioxidant effect of exercise is mediated by the assembly of mitochondrial CIs into SCs in rats. Male Wistar rats were exercise trained or remained sedentary for ten weeks; then, blood samples were collected, and the gastrocnemius muscle was isolated. The assembly of mitochondrial SCs and the lipid peroxidation of the mitochondrial and plasmatic fractions were assessed. Our results demonstrate that exercise induced the assembly of CI into SCs in the gastrocnemius and induced a systemic decrease in lipid peroxidation. We also found an inverse association between the superassembly of CIs and mitochondrial lipid peroxidation (p < 0.01) and protein carbonyls (p < 0.05). We conclude that exercise induces the chronic assembly of CIs into SCs, which provide mitochondrial protection against oxidative damage, at least in the studied muscle. Given the relevant role that mitochondria play in health and disease, these findings should help to elucidate the role of exercise as a therapeutic approach for metabolic diseases.

Gammagrafía de tránsito gastrointestinal en el estudio del estreñimiento crónico en edad pediátrica; una exploración infrecuente / Gastrointestinal transit scintigraphy in chronic constipation evaluation in pediatric age; an infrequent test

Objetivo. El estreñimiento crónico es una enfermedad común en el niño. Nuestro objetivo fue poner de manifiesto la utilidad de la gammagrafía de tránsito gastrointestinal en el estudio de pacientes pediátricos con estreñimiento crónico y las ventajas que tiene respecto a otros estudios de imagen, a pesar de nuestra limitada experiencia. Material y métodos. Se valoraron 5 pacientes remitidos a nuestro servicio con diagnóstico de estreñimiento crónico refractario al tratamiento. Se realizó un protocolo de estudio completo, incluyendo gammagrafía de vaciamiento gástrico para líquidos y tránsito de intestino delgado y grueso, utilizándose una única dosis de 111In-DTPA. Siguiendo guías internacionales se definieron áreas de interés en estómago, íleon terminal y en 6 regiones del intestino grueso. Resultados. Todos los enfermos presentaron estudios gammagráficos alterados, mostrando 4 de ellos exploraciones radiológicas normales. El estudio radioisotópico cambió el diagnóstico del paciente en 2 casos y en otros 2 contribuyó a aclararlo, ante la discordancia entre pruebas radiológicas normales y biopsia rectal patológica. Uno de los pacientes mostró concordancia entre los 2 estudios de imagen. Tras la gammagrafía se produjo cambio en el manejo terapéutico en 2 casos. Conclusiones. Nuestra limitada experiencia coincide con los datos publicados en los que el estudio gammagráfico resulta ser un método reproducible y preciso. Proporciona una información fisiológica, cuantitativa y útil en el estudio del estreñimiento, siendo la única exploración que permite la determinación tanto global como regional del tiempo de tránsito gastrointestinal (AU)

Aim. Chronic constipation is a common pathology in children. The aim of this paper was to show the usefulness of gastrointestinal transit scintigraphy in pediatric patients with chronic constipation, and the advantages with respect to other imaging techniques, despite our limited experience. Material and methods. We evaluated 5 patients sent to our service with a diagnosis of chronic constipation refractory to treatment. We performed a complete study protocol, including liquid gastric emptying scintigraphy and small and large bowel transit times, using a single dose of 111In-DTPA. Following international guidelines regions of interest were defined in stomach, terminal ileum and in 6 regions of the large intestine. Results. All patients showed altered scintigraphy study, showing 4 of them normal radiological tests. Radioisotopic study changed diagnosis in 2 patients and in other 2 patients contributed to clarify it, since discordance between normal radiological tests and abnormal rectal biopsy. One of the patients showed concordance between each imaging modality. The results of the test changed the therapeutic management in 2 cases. Conclusions. Our limited experience coincides with published data in which scintigraphy study turns out to be a reproducible and accurate method. It provides physiological, quantitative and useful information in the study of constipation, being the unique exploration that allows both global and regional gastrointestinal transit time determination (AU)

Gastrointestinal transit scintigraphy in chronic constipation evaluation in pediatric age; an infrequent test. / Gammagrafía de tránsito gastrointestinal en el estudio del estreñimiento crónico en edad pediátrica; una exploración infrecuente.

AIM: Chronic constipation is a common pathology in children. The aim of this paper was to show the usefulness of gastrointestinal transit scintigraphy in pediatric patients with chronic constipation, and the advantages with respect to other imaging techniques, despite our limited experience. MATERIAL AND METHODS: We evaluated 5 patients sent to our service with a diagnosis of chronic constipation refractory to treatment. We performed a complete study protocol, including liquid gastric emptying scintigraphy and small and large bowel transit times, using a single dose of 111In-DTPA. Following international guidelines regions of interest were defined in stomach, terminal ileum and in 6 regions of the large intestine. RESULTS: All patients showed altered scintigraphy study, showing 4 of them normal radiological tests. Radioisotopic study changed diagnosis in 2 patients and in other 2 patients contributed to clarify it, since discordance between normal radiological tests and abnormal rectal biopsy. One of the patients showed concordance between each imaging modality. The results of the test changed the therapeutic management in 2 cases. CONCLUSIONS: Our limited experience coincides with published data in which scintigraphy study turns out to be a reproducible and accurate method. It provides physiological, quantitative and useful information in the study of constipation, being the unique exploration that allows both global and regional gastrointestinal transit time determination.

LEACHING AND DEGRADATION OF 2,4-DICHLOROPHENOXIACETIC ACID, IN COLOMBIA RICE FLOODED SOIL.

Rice is mostly cultivated on soil held under flooded conditions. Under these conditions pesticides undergo reductive transformations which are characteristic to rice fields and other anaerobic systems. The present study was undertaken to evaluate the mobility and persistence of 2,4-dichlorophenoxy acetic acid (2,4-D) under laboratory conditions for the rice crop in Espinal, Colombia. A displacement study was performed on a hand packed soil column 30 cm length. After leaching experiment, the soil from column was sliced into six successive sections (5 cm). Methanol acidified (H3PO4 0.25%) extraction was used to determine the herbicide residues in each section. 2,4-D experimental breakthrough curve was analyzed using Stanmod program (inverse problem) to obtain transport parameters. The non-equilibrium physical model fitted well the experimental breakthrough curve. The recovery percent of 2,4-D in leachates was 36.44% after 3.4 pore volumes, and retardation factor was 2.1, indicating low adsorption in that conditions. 2,4-D was rapidly degraded, with DT50 = 11.4 days. The results suggest that 2,4-D under flooded conditions have a high potential for leaching through the soil profile, although the elevated rate of degradation reduced the ground water contamination risk.

Assessment of the natural sources of particulate matter on the opencast mines air quality.

Particulate matter is the main air pollutant in open pit mining areas. Preferred models that simulate the dispersion of the particles have been used to assess the environmental impact of the mining activities. Results obtained through simulation have been compared with the particle concentration measured in several sites and a coefficient of determination R(2)<0.78 has been reported. This result indicates that in the open pit mining areas there may be additional sources of particulate matter that have not been considered in the modeling process. This work proposes that the unconsidered sources of emissions are of regional scope such as the re-suspension particulate matter due to the wind action over uncovered surfaces. Furthermore, this work proposes to estimate the impact of such emissions on air quality as a function of the present and past meteorological conditions. A statistical multiple regression model was implemented in one of the world's largest open pit coal mining regions which is located in northern Colombia. Data from 9 particle-concentration monitoring stations and 3 meteorological stations obtained from 2009 to 2012 were statistically compared. Results confirmed the existence of a high linear relation (R(2)>0.95) between meteorological variables and particulate matter concentration being humidity, humidity of the previous day and temperature, the meteorological variables that contributed most significantly in the variance of the particulate matter concentration measured in the mining area while the contribution of the AERMOD estimations to the short term TSP (Total Suspended Particles) measured concentrations was negligible (<5%). The multiple regression model was used to identify the meteorological condition that leads to pollution episodes. It was found that conditions drier than 54% lead to pollution episodes while humidities greater than 70% maintain safe air quality conditions in the mining region in northern Colombia.

[Cauda equina syndrome caused by paraganglioma of the filum terminale]. / Paraganglioma del filum terminal como causa de síndrome de cauda equina.

Paragangliomas are neuroendocrine tumors that originate from cells migrating from the neural crest. They have a diverse localizations, and are common in the head, neck, mediastinum or retroperitoneum. Their growth in the filum terminale region is very infrequent. We report the case of a patient who suffered an acute cauda equina syndrome. We give a detailed description of the diagnostic process, radiological characteristics, treatment and the macro and microscopic properties of this tumor.

Paraganglioma del filum terminal como causa de síndrome de cauda equina / Cauda equina syndrome caused by paraganglioma of the filum terminale

Los paragangliomas son tumores neuroendocrinos originados a partir de células que migran de la cresta neural. Su localización es diversa, siendo frecuentes encabeza, cuello, mediastino o retroperitoneo. Su crecimiento en la región del filum terminal es muy poco frecuente. Presentamos el caso de una paciente que debuta con un cuadro agudo de cauda equina. Describimos en detalle el proceso diagnóstico, las características radiológicas, el tratamiento y las propiedades macro y microscópicas de este tumor (AU)

Paragangliomas are neuroendocrine tumors that originate from cells migrating from the neural crest. They have a diverse localizations, and are common in the head, neck, mediastinum or retroperitoneum. Their growth in the filum terminale region is very infrequent. We report the case of a patient who suffered an acute cauda equina syndrome. We give a detailed description of the diagnostic process, radiological characteristics, treatment and the macro and microscopic properties of this tumor (AU)

Anestesia regional para pilomatrixoma: manejo anestésico: a propósito de un caso / Pilomatrixoma for regional anesthesia: anesthetic management: a purpose of a case

El pilomatrixoma es un tumor que deriva de la matrix del folículo piloso. Usualmente se manifiesta como un nódulo firme, solitario y asintomático. Es considerado como un tumor raro. Aproximadamente el 50 por ciento de las lesiones se observan en cabeza y cuello. Se presenta en la mayoría de veces en niños, pero su presentación en adultos es altamente reportada. Es más común en mujeres que en hombres. Su tratamiento se basa en la resección quirúrgica. Múltiples pilomatrixomas se han observado en asociación con distrofias musculares. La técnica anestésica ideal es aquella que permite mantener una adecuada estabilidad hemodinámica intraoperatoria, sin embargo los procedimientos extra e intracraneanos, están asociados a importantes variaciones en los estímulos nociceptivos, debido a lo cual se requiere frecuentes ajuste de la profundidad anestésica, el bloqueo somático de cabeza y cuello, proporciona una forma optima de anestesia, sola o como complemento de anestesia general, y produce una analgesia excelente en el período postoperatorio. En nuestro centro asistencial es frecuente el uso de bloqueo de cuero cabelludo, en los pacientes neuroquirúrgicos, a continuación se describe el uso de anestesia regional en un paciente masculino, con pilomatrixoma, realizada en el Instituto Autónomo Hospital Universitario de Los Andes.