Changes in Pain Perception in Women During and Following an Exhaustive Incremental Cycling Exercise

Exercise has been found to alter pain sensitivity with a hypoalgesic response (i.e., diminished sensitivity to pain) typically reported during and/or following high intensity exercise. Most of this research, however, has involved the testing of men. Thus, the purpose of the following investigation was to examine changes in pain perception in women during and following exercise. Seventeen healthy female subjects (age 20.47±.87; VO2 peak 36.77± 4.95) volunteered to undergo pain assessment prior to, during, and after a graded exhaustive VO2 peak cycling challenge. Heart Rate (HR) and Oxygen Uptake (VO2) were monitored along with electro-diagnostic assessments of Pain Threshold (PT) and Pain Tolerance (PTOL) at: 1) baseline (B), 2) during exercise (i.e., 120 Watts), 3) at exhaustive intensity (VO2 peak), and 4) 10 minutes into recovery (R). Data were analyzed using repeated measures ANOVA to determine differences across trials. Significant differences in PT and PTOL were found across trials (PT, p = 0.0043; PTOL p = 0.0001). Post hoc analyses revealed that PT were significantly elevated at VO2 peak in comparison to B (p = 0.007), 120 Watts (p = 0.0178) and R (p = 0.0072). PTOL were found to be significantly elevated at 120 Watts (p = 0.0247), VO2 peak (p \u3c 0.001), and R (p = 0.0001) in comparison to B. In addition, PTOL were found to be significantly elevated at VO2 peak in comparison to 120 Watts (p = 0.0045). It is concluded that exercise-induced hypoalgesia occurs in women during and following exercise, with the hypoalgesic response being most pronounced following exhaustive exercise

Specificity of hemodynamic brain responses to painful stimuli: a functional near-infrared spectroscopy study

Assessing pain in individuals not able to communicate (e.g. infants, under surgery, or following stroke) is difficult due to the lack of non-verbal objective measures of pain. Near-infrared spectroscopy (NIRS) being a portable, non-invasive and inexpensive method of monitoring cerebral hemodynamic activity has the potential to provide such a measure. Here we used functional NIRS to evaluate brain activation to an innocuous and a noxious electrical stimulus on healthy human subjects (n = 11). For both innocuous and noxious stimuli, we observed a signal change in the primary somatosensory cortex contralateral to the stimulus. The painful and non-painful stimuli can be differentiated based on their signal size and profile. We also observed that repetitive noxious stimuli resulted in adaptation of the signal. Furthermore, the signal was distinguishable from a skin sympathetic response to pain that tended to mask it. Our results support the notion that functional NIRS has a potential utility as an objective measure of pain.Published versio

Tramadol in the elderly : pharmacokinetic and pharmacodynamic modelling in healthy young and elderly subjects

Même si la douleur est très fréquente chez les personnes âgées et que ces dernières sont parmi les plus grands utilisateurs d'analgésiques, les preuves factuelles supportant les décisions médicales sont limitées. Récemment, une revue systématique des essais cliniques portant sur les douleurs aigues au bas du dos a permis de constater que les adultes de plus de 65 ans étaient systématiquement exclus des essais cliniques randomisés en dépit des incitations règlementaires à inclure de tels patients dans ces études. Les données en pharmacocinétique (PK) et pharmacodynamie (PD) concernant les analgésiques chez les patients du troisième âge, particulièrement les personnes âgées de plus de 75 ans, sont rares. Comprendre la relation pharmacocinétique-pharmacodynamique (PK/PD) des médicaments employés pour traiter les conditions qui affectent communément nos ainés est fondamentale pour un traitement optimal leur permettant de conserver une bonne qualité de vie et leur dignité et ce, tout en minimisant les effets secondaires délétères. Le tramadol est un opioïde faible communément employé chez les personnes âgées pour soulager la douleur. Pourtant, il y a peu de données sur sa relation PK/PD chez ces mêmes personnes. Plusieurs essais cliniques visant à établir l’efficacité d’un médicament, et en particulier les analgésiques, produisent des résultats non concluants ou négatifs; les modèles expérimentaux de douleur offrent l'opportunité de comprendre la PD des analgésiques au moyen d’études de plus petite échelle qui minimisent les circonstances environnementales pouvant introduire un biais. Les analyses PK/PD par approche de population permettent d'optimiser les régimes posologiques et de concevoir des essais cliniques qui prennent en considération les connaissances acquises. Le modèle expérimental de douleur employé dans ce programme de recherche nous donne une façon d'évaluer les différences de tolérance à la douleur entre sujets jeunes et âgés de façon quantitative. L'objectif de cette thèse est de contribuer au savoir en caractérisant la relation PK/PD du tramadol et de son métabolite actif, ODM, chez les patients de 75 ans et plus, afin de déterminer s'il existe des différences reliées à l'âge. Nous avons conduit une étude PK et PD à répartition aléatoire, contrôlée par placébo, comportant deux périodes en chassé-croisé. Treize sujets âgés de plus de 75 ans ayant une insuffisance rénale légère et 16 sujets âgés entre 18 et 40 ans ont été recrutés. Des échantillons de sang et d'urine ont été recueillis sur une durée de 48 heures post-dose. Un modèle expérimental de douleur à base de stimulation électrique a été employé pour évaluer le seuil de tolérance à la douleur (PTT), soit l'intensité maximale qu'un sujet est en mesure de tolérer et ce, employant un stimulus douloureux mais non blessant appliqué au doigt non dominant. Le PTT a été testé à des fréquences de 250 et 5 Hertz et ce, à 17 moments sur une période de 30 heures post-dose. Une analyse PK noncompartimentale (NCA) approfondie des concentrations plasmatiques et urinaires du (+) et (-) tramadol et du (+)- et (-)-ODM de même qu'une analyse PK par approche de population du tramadol ont d’abord été exécutées. Ces analyses ont démontré que l'exposition générale au tramadol chez les patients âgés est comparable à celle des plus jeunes. Aucunes différences dans les processus d'absorption n'ont été observées. Cependant, une différence significative a été observée au niveau de la demi-vie d’élimination du tramadol chez les personnes âgées, probablement à cause d’une augmentation de sa distribution corporelle. Les différences les plus notables se situent au niveau de la PK de l'(+)-ODM, le métabolite ayant une activité opioïde. Ses concentrations plasmatiques maximales ont été observées plus tard et ont décru plus lentement chez les personnes âgées que chez les jeunes. L'exposition à l' (+)-ODM était significativement plus grande chez les sujets âgés, et tant la clairance rénale que la clairance corporelle totale étaient plus lentes. L’analyse PK populationnelle a confirmé ces observations et identifié qu'une distribution supérieure de même qu'une élimination moyenne de 50% plus longue pour le tramadol chez les sujets âgés. Il est important de souligner que, dans notre groupe de personnes âgées, l'insuffisance rénale était plus fréquente que l'insuffisance hépatique. Par la suite, avant de procéder à l’analyse populationnelle pour établir une relation entre les concentrations de l’ODM et les seuils de tolérance à la douleur, nous avons analysé les données pharmacodynamiques sous les périodes placébo et tramadol afin de valider le nouveau modèle expérimental de douleur proposé. Nous souhaitions sélectionner le stimulus électrique (5 Hz ou 250 Hz) qui soit le plus sensible pour détecter un changement au niveau de hla tolérance à la douleur. Tant les jeunes sujets que les plus âgés ont démontré des valeurs de base similaires pour le seuil de tolérance à la douleur et ce, aux deux fréquences sous administration active et placébo. Chez les personnes âgées, la valeur maximale du PTT était de 30% supérieure sous tramadol comparativement au placébo et ce, tant à 5 Hz que 250 Hz; toutefois, la réponse était plus variable pour la dernière fréquence. La tolérance à la douleur, telle que mesurée par la surface sous la courbe de l’effet en fonction du temps (AUEC) sur une période de 24 heures, était significativement plus élevée (au-delà de 160%) chez les personnes âgées pendant le traitement actif comparativement au placebo pour les deux fréquences de stimulation; toutefois, aucune différence significative au niveau de la tolérance n'a été observée chez les plus jeunes. Nous avons émis l’hypothèse que cette différence pouvait résulter de la plus grande exposition des sujets âgés à l' (+)-ODM. Par conséquent, une analyse PK/PD devenait nécessaire pour déterminer si ces changements au niveau du seuil de tolérance à la douleur chez les personnes âgées étaient reliés à une plus grande exposition à l'(+)-ODM. Finalement, en utilisant des concentrations plasmatiques de (+)-ODM et les données PTT obtenues avec le stimulus de 5 Hz, nous avons conduit une analyse populationnelle exploratoire pour déterminer tout effet de l'âge sur la relation entre les concentrations plasmatiques de (+)-ODM et la tolérance à la douleur. En dépit de valeurs de base semblables pour la tolérance à la douleur, l'effet maximal possible relié au traitement était de 15% supérieur chez les sujets âgés, ce qui pourrait s’expliquer par une exposition plus élevée au métabolite actif, confirmant son mécanisme d'action opioïde. La concentration plasmatique associée à 50% de l’effet maximal n’était pas différente chez le sujet jeune et âgé, indiquant que l’âge n’est pas associé avec une plus grande sensibilité à l’ (+)-ODM. En conclusion, ceci est le premier programme de recherche ayant étudié extensivement la PK et PD du tramadol chez les patients de 75 ans et plus. La valeur de ce programme de recherche va au-delà d'une meilleure compréhension de la PK du tramadol, en améliorant notre compréhension des contributions relatives des clairances rénale et totale au niveau des changements survenant avec l'âge pour la PK du tramadol et de son métabolite actif chez les personnes âgées en relativement bonne santé. Ce programme contribue également au développement de modèle permettant d’effectuer davantage de recherches chez les personnes âgées puisqu’il est le premier modèle PK/PD populationnel de (+)-ODM chez les sujets de 75 ans et plus. Nos analyses démontrent que les changements reliés à l'âge dans la clairance rénale peuvent résulter en un accroissement proportionnel de l'exposition à l'ODM, et pourraient expliquer les observations faites par certains cliniciens dans la littérature qui rapportent une augmentation des effets (secondaires) à des doses équivalentes chez les personnes âgées. Ceci est d’autant plus de pertinence clinique que l'efficacité et les effets secondaires du tramadol découlant de sa nature opiacée, notamment la sédation, sont principalement reliés à l’(+)-ODM et le seraient davantage chez des patients âgés fragilisés souffrant d’une insuffisance rénale plus prononcée que celle des sujets étudiés au cours de notre recherche.Although pain is highly prevalent among the elderly and they are amongst the highest users of analgesics, research to support evidence based treatment decisions is limited. Recently a systematic review of clinical trials in low back pain found that elderly adults older than 65 were systematically excluded from randomised clinical trials despite calls to include elderly subjects in such studies. Pharmacokinetic (PK) and Pharmacodynamic (PD) data on analgesics in elderly patients, especially those older than 75 years, is sparse. Understanding the pharmacokinetic/pharmacodynamic relationship (PK/PD) of medicines used to treat conditions that commonly affect elderly people is key to treating them effectively, allowing them to live with quality of life and dignity and minimising the side effects that can interfere with this. Tramadol is a weak opioid commonly used in elderly patients for pain relief. Yet there is little data on its PK/PD in the elderly. Many later phase clinical trials, especially in analgesics produce inconclusive or negative results; experimental pain models offer the opportunity to understand the PD of analgesics on a smaller scale and minimise confounding environmental circumstances. Population PK/PD analyses of early research data permit the optimisation of dosing regimens and of the design of phase III clinical trials by taking into account what is learned. The pain model utilised in this research program gives us a way to look at the differences in pain tolerance between young and elderly in a quantitative fashion. The objective of this thesis is to contribute to the knowledge about age-related differences in the PK/PD of tramadol and its active metabolite O-desmethyltramadol (ODM) in subjects 75 years and older in order to examine whether there are age-related differences. We conducted a double-blind randomised, placebo-controlled, two-period crossover study including 13 elderly subjects (≥75 years) with mild renal insufficiency and 16 young (18-40 years) subjects. Blood samples and urine were collected for 48 hours post-dose. An electrically stimulated pain model (ESPM) was used to test pain tolerance threshold (PTT), the maximum intensity a subject is willing to tolerate, using a painful but non-injuring electrical stimulus applied to the non-dominant middle finger. PTT was tested at both 250 and 5 Hz at each of 17 time-points over 30 hours after a 200 mg dose of extended release tramadol . An in depth noncompartmental analysis of the PK of (+)- and (-)-tramadol and (+)- and (-)-ODM plasma and urine concentrations as well as a population PK analysis of tramadol were performed. Maximum plasma concentrations of (+)-ODM, the active metabolite, occurred later and plasma concentrations declined more slowly in the elderly than in young subjects. These analyses showed that overall exposure to tramadol in elderly subjects is comparable to that in young subjects. No differences in absorption processes were observed. However, there was a significant difference in tramadol elimination half-life, most probably due to increased distribution in elderly subjects. The most remarkable differences were in the PK of (+)-ODM, the metabolite with opioid activity. Exposure to ODM was significantly greater in elderly subjects and both renal and overall clearance from the body were slower. The population PK analysis supported our findings and identified that a higher distribution and a 50% longer mean elimination half-life was associated with age of 75 or older. A key observation was that in our study population renal insufficiency was more prevalent in the elderly subjects than hepatic insufficiency. Subsequently, in preparation for a population analysis of the PK and pain tolerance effect of tramadol’s active metabolite, (+)-ODM, we analysed pain tolerance data under placebo and tramadol administration to validate the exploratory experimental pain model that we used. We wanted to select the electrical stimulus (5 Hz or 250 Hz) that was most sensitive to detect changes in pain tolerance. Young and elderly subjects showed similar baseline pain tolerance at both 5 Hz and 250 Hz before administration of active and placebo, suggesting that pain tolerance is similar in either frequency. In the elderly, the peak pain tolerance was 30% greater for both 5 and 250 Hz after administration of tramadol as compared to placebo, but the response was noisier for the last frequency. The net pain tolerance over the 24 hours, as measured by area under the effect-time curve (AUEC) during active treatment was significantly higher (over 160%) compared to placebo for both 5 and 250 Hz stimulations in the elderly but no significant difference was observed in the young. We hypothesised that this difference might be due to the higher exposure of elderly subjects to ODM. And therefore, a PK/PD analysis was required to determine whether these age-related changes were due to altered sensitivity in elderly subjects to PTT or to a greater exposure to the active (+)-ODM metabolite. Finally utilising plasma concentrations of (+)-ODM and the PTT data from the 5 Hz stimulus, we conducted an exploratory population analysis to determine any age-related effects on the relationship between (+)-ODM concentrations and pain tolerance threshold. Although pain tolerance was similar between young and elderly subjects at baseline, there was a 15% higher maximum possible treatment-related effect that may be associated with the higher systemic exposure to ODM., the active metabolite, thereby confirming its opioid mechanism of action. The concentration at which 50% of effect was achieved was not reduced between the young and elderly, indicating that age was not associated with greater sensitivity to (+)-ODM. In conclusion, this is the first research program to extensively report the PK and PD of tramadol in subjects 75 and older. The value of this research program goes beyond that of a better understanding of the PK of tramadol, by delineating the relative contribution of renal clearance versus overall clearance to age-related alterations in the PK of tramadol and ODM in generally healthy elderly people. This research program also contributes to the development of population models to support further research in the elderly being the first population PK/PD model developed for (+)-ODM in subjects 75 and older. Our findings show that age-related changes in renal clearance versus overall clearance can result in a proportional increase in ODM exposure, and may explain the observation of some clinicians and literature that there is increased side effects at equivalent doses in the elderly. This is potentially of clinical significance since opioid-related efficacy and side effects of tramadol, among them sedation, are primarily linked to (+)-ODM and the risk of side effects would likely be greater in frail elderly subjects with greater renal impairment than those studied in our research

Short-term sensory and cutaneous vascular responses to therapeutic ultrasound in the forearms of healthy volunteers

© 2014 Shaik et al. Background: Therapeutic ultrasound (US) is used for a variety of clinical pathologies and is thought to accelerate tissue repair and help with pain reduction via its thermal and nonthermal effects. The evidence on physiological effects of US on both sensory and vascular functions in humans is incomplete. Hence, the purpose of this study was to determine the short-term impact of two doses of US (3 MHz, 1:4, 0.25 W/cm2, 5 min; 1 MHz, continuous, 0.8 W/cm2, 3 min), on sensory and vascular responses in the healthy forearms. Methods: Twenty healthy subjects were recruited (mean age, 29.6 ± 8.8 years) for the study. Superficial blood flow (SBF) in the distal forearms was determined using the tissue viability imaging system. Sensory perception thresholds (SPT) were determined from ring finger (C7, C8) to assess A-beta (at 2,000 Hz) and C fiber function (at 5 Hz), using a Neurometer CPT/C device. Subject\u27s two hands were randomly allocated to group order (AB/BA). Scores were obtained before and immediately after the application of US and control. Differences in these were analyzed using repeated measures. Results: Both 3 MHz pulsed US and 1 MHz continuous US showed small to moderate (effect size = 0.12 to 0.68), statistically significant reductions in SBF (3 MHz, mean change = 2.8 AU and 1 MHz, mean change = 3.9 AU, p \u3c 0.05 respectively), skin temperature (2.5°C and 1.1°C, p \u3c 0.05), and SPT at 5 Hz (1.3 and 1 mA, p \u3c 0.05) across time. SPT at 2,000 Hz remained unaltered by all three conditions (p \u3e 0.05). Age and gender also had no effect on all outcome measures (p \u3e 0.05). Conclusion: This study demonstrated minor reductions in skin blood flow, skin temperatures, and C fiber perception thresholds immediately after 3 MHz, and 1 MHz US. The responses observed may have been due to a thermo-cooling effect of the gel or due to the direct effect of US on C fibers ofmedian and ulnar nerves. US had a negligible effect on A-beta fibres. This would suggest that future studies looking at physiological effects of US should move towards investigating larger dosages and study the effects in patient populations

Neuroscience

Prolonged occupational exposure to hand-held vibrating tools leads to pain and reductions in tactile sensitivity, grip strength and manual dexterity. The goal of the current study was to use a rat-tail vibration model to determine how vibration frequency influences factors related to nerve injury and dysfunction. Rats were exposed to restraint, or restraint plus tail vibration at 62.5\u202fHz or 250\u202fHz. Nerve function was assessed using the current perception threshold (CPT) test. Exposure to vibration at 62.5 and 250\u202fHz, resulted in a reduction in the CPT at 2000 and 250-Hz electrical stimulation (i.e. increased A\u3b2 and A\u3b4, nerve fiber sensitivity). Vibration exposure at 250\u202fHz also resulted in an increased sensitivity of C-fibers to electrical stimulation and thermal nociception. These changes in nerve fiber sensitivity were associated with increased expression of interleukin (IL)-1\u3b2 and tumor necrosis factor (TNF)-\u3b1 in ventral tail nerves, and increases in circulating concentrations of IL-1 \u3b2 in rats exposed to 250-Hz vibration. There was an increase in glutathione, but no changes in other measures of oxidative activity in the peripheral nerve. However, measures of oxidative stress were increased in the dorsal root ganglia (DRG). These changes in pro-inflammatory factors and markers of oxidative stress in the peripheral nerve and DRG were associated with inflammation, and reductions in myelin basic protein and post-synaptic density protein (PSD)-95 gene expression, suggesting that vibration-induced changes in sensory function may be the result of changes at the exposed nerve, the DRG and/or the spinal cord.CC999999/Intramural CDC HHS/United States2019-11-01T00:00:00Z30553794PMC6545897691

Short term sensory and vascular responses to physical agent modalities and exercise in healthy volunteers and patients with distal radius fracture.

Currently, there is weak evidence on the effectiveness of different rehabilitation regimens following distal radius fracture (DRF). This thesis evaluated sensory and vascular effects of exercise, thermal and ultrasound interventions that can be used in the mobilization phase (cast removal) after DRF. Methods This thesis includes 3 studies. The first study compared responses to Immersion in Cold water Evaluation (ICE) in the DRF and uninjured hands. Skin blood flow (Sbf), skin temperature (temp.) and sensory perception thresholds (sPT) at 2000Hz for A –beta fibres and at 5 Hz for C fibres were obtained before, immediately after ICE and 10 min later. The second study assessed Sbf, temp., and sPT before and after 3 conditions: control, 1 MHz continuous and 3 MHz pulsed US in healthy subjects. The third study assessed Sbf and sPT before and after 3 conditions: control, 5 min of high intensity and low intensity hand exercises in healthy subjects. Differences in these were analyzed using General Linear Models. Results In the DRF hand, Sbf increased (Mean Difference (MD) = -42.2 A.U.) immediately, at 1 min (MD= -35 A.U.), and 10 min after ICE (MD= -1 A.U.). There was a decrease in temp. for the index and little fingers immediately after ICE (MD=9. 9 & 9.1 o C) and these did not return to baseline by 10 min (MD= 4.4 & 4 o C). ICE had no effect on sPT at 5 Hz (p\u3e0.05). There was no difference between the DRF and uninjured hand on all measures(p\u3e0.05) except for the sPT at 2000Hz, which remained high on the DRF side for up to 10 min( MD= -1.8 m. A.). Both pulsed and continuous US caused small to moderate reductions in Sbf (MD= 2.8 A.U. & 3.9 A.U.), temp. (MD = 2.5 0 C & 1.1 0 C) and sPT at 5 Hz (MD=1.3 m. A. & 1 m. A.). US had no effect on sPT at 2000Hz (p\u3e0.05). Both type of exercises were insufficient to alter Sbf and sPT at 2000Hz and 5 Hz (p\u3e0.05). Conclusions Normal thermo-physiological responses were observed after ICE in both hands. A-beta fibres on the DRF side became less sensitive after ICE. Minor changes can occur in Sbf, temp., and sPT at 5 Hz following 3 to 5 min exposure to US in healthy subjects. Hand grip exercises had minimal impact on Sbf or sPT in healthy subjects. The changes seen with ICE and US are presumed to help with tissue healing and pain modulation which needs further investigation

Outcomes of Tinnitus Post-Cochlear Implantation in Adult Populations: A Systematic Review

The purpose of this investigation is to conduct a systematic review on the outcomes of tinnitus, in both its characteristics and psychosocial impact, post-cochlear implantation in profound bilateral and single-sided deafness (SSD) adult populations. A longitudinal case study will also be presented to show long-term effects of tinnitus outcomes in a cochlear implant recipient in a clinical setting. The investigation may, in turn, provide information regarding tinnitus in the selection criteria of which ear to implant, considerations in implantation eligibility for patients with bilateral and unilateral severe hearing loss associated with severe tinnitus, and to inform patients about the possible risk of postoperative tinnitus worsening. The collective data may also encourage further assessment of tinnitus in cochlear implant (CI) patients during audiological testing

Thermal quantitative sensory testing in healthy Dutch children and adolescents standardized test paradigm and Dutch reference values

Background: Quantitative sensory testing (QST) is often used to measure children's and adults' detection- and pain thresholds in a quantitative manner. In children especially the Thermal Sensory Analyzer (TSA-II) is often applied to determine thermal detection and pain thresholds. As comparisons between studies are hampered by the different testing protocols used, we aimed to present a standard protocol and reference values for thermal detection- and pain thresholds in children. Methods: Our standard testing protocol includes reaction time dependent and independent tests and takes about 14-18 min to complete. Reference values were obtained from a sample of 69 healthy term born children and adolescents with a median age of 11.2 years (range 8.2 to 17.9 years old). Seventy-one children were recruited and data of 28 males and 41 females was obtained correctly. We studied possible age and sex differences. Results: This study provides Dutch reference values and presents a standard quantitative sensory testing protocol for children with an age from 8 years onwards. This protocol appeared to be feasible, since only two out of 71 participants were not able to correctly complete the protocol due to attention deficits and were therefore excluded. We found some significant age and sex differences: females were statistically significantly more sensitive for both cold and heat pain compared to males, and the youngest children (8-9 years old) were less sensitive to detect a warm stimulus. The youngest children tend to be more sensitive to heat pain in comparison to older participants, although the difference was not statistically significant. Conclusions: We present a feasible thermal quantitative sensory testing protocol for children and reference values that are easy to interpret and may serve as normative values for future studies

Chest tube insertion is one important factor leading to intercostal nerve impairment in thoracic surgery

Objectives: Chest tube insertion seems to be one important factor leading to intercostal nerve impairment. The purpose of this prospective study was to objectively evaluate intercostal nerve damage using current perception threshold testing in association with chest tube insertion. Methods: Sixteen patients were enrolled in this study. Intercostal nerve function was assessed with a series of 2000-Hz (Aβ fiber), 250-Hz (Aδ fiber), and 5-Hz (C fiber) stimuli using current perception threshold testing (Neurometer CPT/C R). Current perception threshold values at chest tube insertion were measured before surgery, during chest tube insertion and after removal of the chest tube. Intensities of ongoing pain were also assessed using a numeric rating scale (0-10). Results: Current perception thresholds at each frequency after surgery were significantly higher than before surgery. Numeric rating scale scores for pain were significantly reduced from 3.3 to 1.9 after removal of the chest tube (p = 0.004). The correlation between current perception threshold value at 2000 Hz and intensity of ongoing pain was marginally significant (p = 0.058). Conclusions: This is the first study to objectively evaluate intercostal nerve damage at chest tube insertion. The results confirmed that chest tube insertion has clearly deleterious effects on intercostal nerve function

Research on the utilization of pattern recognition techniques to identify and classify objects in video data Final report

Spaceborne pattern recognition system for identifying and classifying objects in video dat