Assessment of sudomotor function.

PURPOSE: To review the currently available literature on clinical autonomic tests of sudomotor function. METHODS: We searched PubMED/MEDLINE for articles on technical principles and clinical applications of sudomotor tests with a focus on their drawbacks and perspectives in order to provide a narrative review. RESULTS: The quantitative sudomotor axon reflex sweat test (QSART) is the most widely used test of sudomotor function. The technique captures pathology with low intra- and inter-subject variability but is limited by technical demands. The thermoregulatory sweat test comprises topographic sweat pattern analysis of the ventral skin surface and allows differentiating preganglionic from postganglionic sudomotor damage when combined with a small fiber test such as QSART. The sympathetic skin response also belongs to the more established techniques and is used in lie detection systems due to its high sensitivity for sudomotor responses to emotional stimuli. However, its clinical utility is limited by high variability of measurements, both within and between subjects. Newer and, therefore, less widely established techniques include silicone impressions, quantitative direct and indirect axon reflex testing, sensitive sweat test, and measurement of electrochemical skin conductance. The spoon test does not allow a quantitative assessment of the sweat response but can be used as bedside-screening tool of sudomotor dysfunction. CONCLUSION: While new autonomic sudomotor function testings have been developed and studied over the past decades, the most were well-studied and established techniques QSART and TST remain the gold standard of sudomotor assessment. Combining these techniques allows for sophisticated analysis of neurally mediated sudomotor impairment. However, newer techniques display potential to complement gold standard techniques to further improve their precision and diagnostic value.

Cholinergic urticaria: epidemiology, physiopathology, new categorization, and management.

PURPOSE: The aim of this study was to review the evidence on the epidemiology, physiopathology, categorization, and management of cholinergic urticaria. We specifically focused on several subtypes of cholinergic urticaria and investigated the relationship between cholinergic urticaria and idiopathic anhidrosis. METHODS: Using an integrative approach, we reviewed publications addressing the epidemiology, clinical features, diagnostic approach, physiopathology, subtype classification, and therapeutic approach to cholinergic urticaria. RESULTS: Multiple mechanisms were found to contribute to the development of cholinergic urticaria. This disorder should be classified based on the pathogenesis and clinical characteristics of each subtype. Such a classification system would lead to better management of this resistant condition. In particular, sweating function should be given more attention when examining patients with cholinergic urticaria. CONCLUSIONS: Because cholinergic urticaria is not a homogeneous disease, its subtype classification is essential for selection of the most suitable therapeutic method.

Iodine-Starch test for assessment of hyperhidrosis in amputees, evaluation of different methods of application.

PURPOSE: Hyperhidrosis is a common problem for amputees. The iodine-starch test is frequently used to assess hyperhidrosis, but a method for its application has not been described for amputees. METHODS: We performed an unblinded comparison of the iodine-starch test using various methods to protect the prosthesis in 10 prosthetic limb users with hyperhidrosis. RESULTS: Plastic wrap produced a diffuse pattern of sweating in 70% of subjects. Forty percent had complaints about this method, and 50% experienced leakage of iodine stain onto prosthetic liners. The prosthetic sheath produced a focal or multifocal reaction in 100% of subjects after 10 min of ambulation. Eighty percent had minor leakage onto the liner, and complaints were noted in 10%. The proportion that experienced diffuse sweating was significantly higher in the plastic wrap condition (p = 0.016; difference in proportions = 70%; 95% confidence interval = 32-100%). The prosthetic sock was tested in four subjects and all had at least mild complaints; three had minor leakage onto the liner. Repeated complaints and lack of stain prevention led to discontinuation with this method. CONCLUSIONS: Of the three methods, the sheath produces a focal or multifocal reaction after 10 min of ambulation and tends to cause less subject complaints. It should be the preferred method to apply the iodine-starch test to amputees. Implications for rehabilitation Hyperhidrosis is a common problem in amputees which negatively affects quality of life. The iodine-starch test is commonly used to guide treatment decisions for hyperhidrosis, but a preferred method for applying it in amputees has not been described. This study describes different methods for applying the iodine-starch test. A prosthetic sheath covering should be the preferred method for the iodine-starch test in amputees.

High temperatures and nephrology: The climate change problem. / Altas temperaturas y nefrología: a propósito del cambio climático.

It is well known that climate change greatly affects human health, even though there are few studies on renal outcomes. Heat waves have been found to increase cardiovascular and respiratory morbidity and mortality, as well as the risk of acute renal failure and hospitalisation due to renal diseases, with related mortality. Recurrent dehydration in people regularly exposed to high temperatures seems to be resulting in an unrecognised cause of proteinuric chronic kidney disease, the underlying pathophysiological mechanism of which is becoming better understood. However, beyond heat waves and extreme temperatures, there is a seasonal variation in glomerular filtration rate that may contribute to the onset of renal failure and electrolyte disorders during extremely hot periods. Although there are few references in the literature, serum sodium disorders seem to increase. The most vulnerable population to heat-related disease are the elderly, children, chronic patients, bedridden people, disabled people, people living alone or with little social contact, and socioeconomically disadvantaged people.

Miniature hygrometric hot flush recorder as an objective indicator of hot flushes: a validation study.

OBJECTIVE: Hot flushes are a very common symptom of menopause for which many women seek medical help. Accurate assessment of clinical severity and of the impact of treatment is limited by a lack of methods for objective hot flush recording. The aim of the current study is to test the diagnostic value of a miniature hygrometric hot flush recorder (HFR). METHODS: The HFR was tested in 50 women with severe postmenopausal hot flushes. Results were compared with recordings in 27 asymptomatic postmenopausal women, 12 premenopausal women, and 12 age-matched healthy men. The number of HFR events was compared with the number of diary-reported hot flushes. RESULTS: Healthy young women and men had a mean (SEM) of 17.3 (1.3) HFR events/day. Asymptomatic postmenopausal women had 13.6 (1.4) HFR events/day, whereas symptomatic postmenopausal women had 21.0 (1.0) HFR events/day (P < 0.001). The number of HFR events in symptomatic women was significantly higher than the number of diary-reported hot flushes (mean [SEM], 13.8 [0.6] hot flushes/d) (P < 0.001). HFR sensitivity to diary-reported hot flushes was 55.1%, with 61.4% specificity. CONCLUSIONS: The miniature hygrometric HFR has limited sensitivity and specificity. It detects sweating in general but does not differentiate between natural sweating and hot flush-related sweating. However, it may become useful as a tool for improving the data quality of diary-reported hot flushes.

IMS study of climate, altitude, temperature and vasomotor symptoms in the United Arab Emirates.

OBJECTIVE: To examine the relationships between temperature, season (summer versus winter), lifestyle, health, mood, beliefs, and experience of hot flushes and night sweats (HFNS), amongst mid-aged women living in the United Arab Emirates (UAE). METHODS: The UAE climate is hyper-arid, being a hot desert climate, with warm winters and hot summers. A total of 372 peri- and postmenopausal women, aged from 45 to 55 years, from urban UAE regions were included. Data were collected during both summer and winter months. Participants completed questionnaires eliciting information about sociodemographics, HFNS (prevalence, frequency and problem-rating), health and lifestyle (body mass index (BMI), diet, exercise), mood (Women's Health Questionnaire) and menopause attributions and beliefs (Menopause Representations Questionnaire). RESULTS: HFNS were currently being experienced by 46.5% of women, with an average weekly frequency of five and problem-rating of 5.7/10. Seasonal variation in temperature was not associated with prevalence, frequency or problem-rating. Hot flush prevalence was associated with poor health, life satisfaction, mood, employment, lower BMI and diet. Higher frequency was associated with higher BMI and more years since the last period. HFNS were more problematic mainly for women who reported lower life satisfaction and held more negative beliefs about the menopause. CONCLUSIONS: In this UAE study, temperature and seasonal temperature variation did not appear to influence HFNS-reporting, but health, life satisfaction, BMI, beliefs and lifestyle factors partially explained women's experiences of menopausal symptoms. A qualitative study might provide further information about the meanings of HFNS and menopause amongst UAE women.

An International Menopause Society study of climate, altitude, temperature (IMS-CAT) and vasomotor symptoms in urban Indian regions.

OBJECTIVE: To examine the relationships between climate (season, temperature, humidity), lifestyle, health, mood and beliefs and experience of hot flushes and night sweats amongst mid-aged women living in eight urban Indian centers. METHODS: A total of 717 peri- and postmenopausal women, aged 45-55 years, from urban centers in different regions of India were included. Data were collected during both summer and winter months. Participants completed questionnaires eliciting information about sociodemographics, hot flushes (prevalence, frequency and problem-rating), health and lifestyle (body mass index, diet, exercise, alcohol use), mood (Women's Health Questionnaire) and attributions and beliefs (Menopause Representations Questionnaire). RESULTS: The prevalence of vasomotor symptoms was low, with 34% of the sample reporting hot flushes and/or night sweats. Seasonal variation in temperature was not associated with hot flush prevalence, frequency or problem rating. Hot flush prevalence was mainly associated with higher anxiety and intake of spicy foods, frequency with (older) age and (more) frequent exercise, while hot flushes were more problematic for women who reported poorer general health and more negative beliefs about menopause. CONCLUSIONS: In this study of Indian women, seasonal temperature variation did not appear to influence hot flush reporting. Health, mood, beliefs and lifestyle factors appear to explain some, but not all, of the variance in experience of menopausal symptoms.

Gravimetry in sweating assessment in primary hyperhidrosis and healthy individuals.

OBJECTIVE: Though hyperhidrosis is generally considered a subjectively perceived disease, it seems more and more doubtful that merely subjective evaluation is sufficient to qualify the patient to surgery. The aim of this study was to develop further gravimetry as a method of evaluation of sweating intensity and determination of the applicability of it in post-operative follow-up of primary hyperhidrosis (PHH) patients. METHODS: Total of 1,485 gravimetry assays has been performed in 343 patients treated for hyperhidrosis and in 220 healthy volunteers. In all of the subjects the measurements were taken from four localizations (face, hands, armpits and trunk) and normalized by body surface of the participant. The measurements were taken twice for every participant to obtain test-retest correlations. Mean values and standard deviations (SD) have been evaluated and on that basis reference values were quantified. Thresholds for diagnosis of hyperhidrosis were quantified on the basis of normal distribution theory as healthy population mean +2 SD. RESULTS: In healthy volunteers, mean value of gravimetrically evaluated intensity of sweating were: facial: 19.15 ± 14.97 mg/min/m(2), palmar: 18.49 ± 14.06 mg/min/m(2), axillary: 42.39 ± 47.08 mg/min/m(2) and plantar: 15.77 ± 16.87 mg/min/m(2). Thresholds for diagnosis of hyperhidrosis were quantified, respectively as: 49, 46, 136 and 50 mg/min/m(2). The overall test-retest correlation was 0.71. INTERPRETATION: Gravimetry is easy, reproducible and fast method of evaluation of sweating. The reference values are stable and can serve as a qualifying and follow-up tool for evaluation of the patients with PHH in any localization.

Quantitative assessment of the intensity of palmar and plantar sweating in patients with primary palmoplantar hyperhidrosis.

OBJECTIVE: To compare individuals with and without hyperhidrosis in terms of the intensity of palmar and plantar sweating. METHODS: We selected 50 patients clinically diagnosed with palmoplantar hyperhidrosis and 25 normal individuals as controls. We quantified sweating using a portable noninvasive electronic device that has relative humidity and temperature sensors to measure transepidermal water loss. All of the individuals had a body mass index of 20-25 kg/cm². Subjects remained at rest for 20-30 min before the measurements in order to reduce external interference. The measurements were carried out in a climate-controlled environment (21-24ºC). Measurements were carried out on the hypothenar region on both hands and on the medial plantar region on both feet. RESULTS: In the palmoplantar hyperhidrosis group, the mean transepidermal water loss on the hands and feet was 133.6 ± 51.0 g/m²/h and 71.8 ± 40.3 g/m²/h, respectively, compared with 37.9 ± 18.4 g/m²/h and 27.6 ± 14.3 g/m²/h, respectively, in the control group. The differences between the groups were statistically significant (p < 0.001 for hands and feet). CONCLUSIONS: This method proved to be an accurate and reliable tool to quantify palmar and plantar sweating when performed by a trained and qualified professional.

Avaliação quantitativa da intensidade da transpiração palmar e plantar em pacientes portadores de hiperidrose palmoplantar primária / Quantitative assessment of the intensity of palmar and plantar sweating in patients with primary palmoplantar hyperhidrosis

OBJETIVO: Comparar a intensidade de transpiração em palmas das mãos e planta dos pés de indivíduos portadores de hiperidrose com a de um grupo controle. MÉTODOS: Foram selecionados 50 pacientes com diagnóstico clínico de hiperidrose palmoplantar e 25 indivíduos controles. Um método objetivo de quantificação da transpiração foi utilizado com um aparelho eletrônico portátil, não invasivo, com sensores de umidade relativa e de temperatura capazes de quantificar a perda de água transepidérmica. Todos os indivíduos apresentavam índice de massa corpórea de 20-25 kg/cm² e permaneceram em repouso por 20-30 min antes das medições para reduzir a interferência externa. A mensuração foi realizada em sala climatizada com a temperatura de 21-24ºC. Os locais determinados para a aferição foram região hipotenar da face palmar e região medial da face plantar. RESULTADOS: No grupo com hiperidrose palmoplantar, as médias da intensidade de transpiração nas mãos e nos pés foram de, respectivamente, 133,6 ± 51,0 g/m²/h e 71,8 ± 40,3 g/m²/h, enquanto, no grupo controle, essas foram de 37,9 ±18,4 g/m²/h e 27,6 ± 14,3 g /m²/h. As diferenças das médias entre os grupos foram estatisticamente significativas (p < 0,001). CONCLUSÕES: Este método de quantificação mostrou-se uma ferramenta precisa e confiável na avaliação da transpiração palmar e plantar, quando operado por um profissional treinado e capacitado.

OBJECTIVE: To compare individuals with and without hyperhidrosis in terms of the intensity of palmar and plantar sweating. METHODS: We selected 50 patients clinically diagnosed with palmoplantar hyperhidrosis and 25 normal individuals as controls. We quantified sweating using a portable noninvasive electronic device that has relative humidity and temperature sensors to measure transepidermal water loss. All of the individuals had a body mass index of 20-25 kg/cm². Subjects remained at rest for 20-30 min before the measurements in order to reduce external interference. The measurements were carried out in a climate-controlled environment (21-24ºC). Measurements were carried out on the hypothenar region on both hands and on the medial plantar region on both feet. RESULTS: In the palmoplantar hyperhidrosis group, the mean transepidermal water loss on the hands and feet was 133.6 ± 51.0 g/m²/h and 71.8 ± 40.3 g/m²/h, respectively, compared with 37.9 ± 18.4 g/m²/h and 27.6 ± 14.3 g/m²/h, respectively, in the control group. The differences between the groups were statistically significant (p < 0.001 for hands and feet). CONCLUSIONS: This method proved to be an accurate and reliable tool to quantify palmar and plantar sweating when performed by a trained and qualified professional.

Assessment of CFTR function in homozygous R117H-7T subjects.

BACKGROUND: R117H is a frequent missense mutation included in most CFTR mutation panels. However knowledge about the residual function of R117H-CFTR channels in cystic fibrosis-affected organs, e.g. airways, intestines and sweat glands is presently lacking. METHODS: We evaluated clinical CF symptoms and assessed CFTR function by sweat tests, nasal potential difference and intestinal current measurements in 2 homozygous R117H individuals (7T variant). RESULTS: The CFTR activity in airways and intestine was within the normal range. However both individuals presented with a borderline sweat test and the male patient was infertile. CONCLUSIONS: The lack of impact of the R117H mutation on chloride secretion in intestine and nose contrasts with the ~80% loss of CFTR activity reported in patch clamp studies. Apparently CFTR activity is not rate-limiting for chloride secretion in both tissues at levels >20% of normal, or compensatory factors may operate that are absent in heterologous host cells in vitro.

AQP-1 association with body fluid loss in 10-km runners.

Intrinsic body fluid regulation is critical for optimizing endurance performance. Aquaporins (AQPs) are a family of transmembrane proteins that transport water and glycerol across cellular membranes. A recent report revealed an association between a single nucleotide polymorphism (SNP) in the 3' untranslated region of the aquaporin-1 (AQP1) gene and endurance performance. The purpose of the study was to explore the association between the AQP1 SNP and acute body fluid loss in long distance runners. The subjects (N=91, Age=26±3 yrs; Ht=170±11 cm; Wt=61±5 kg; mean±SD) were biologically unrelated male long distance runners. Data were collected before and after an international 10 km road race. Body fluid loss was determined by the difference between nude body weight before and after the 10 km run. The AQP1 (G→C) gene variation was detected by the ARMS-PCR procedure. Genotypes were determined by PCR product size. Carriers of the AQP1 SNP had a significantly greater adjusted body fluid loss (3.7±0.9 kg) than non-carriers (1.5±1.1 kg) (P<0.05). In conclusion, our study found an association between the AQP1 SNP and acute body fluid loss in long distance runners.

The isolated sympathetic spinal cord: Cardiovascular and sudomotor assessment in spinal cord injury patients: A literature survey.

OBJECTIVES: To present a comprehensive approach to the assessment of the severity of the autonomic lesion in spinal cord injury (SCI) patients, with regard to the level of lesion. To discuss how to assess an isolated sympathetic spinal cord that has lost supraspinal control (sympathetically complete lesion). METHOD: PubMed was searched for articles related to cardiovascular (mainly cold pressor test, respiratory and postural challenges) and sudomotor (sympathetic skin responses) tests that have been used. The results of these evaluations are analysed with regard to the site of stimulation (above or below the lesion) according to three types of SCI that offer typical autonomic reactions (tetraplegics, paraplegics at T6 and at T10). RESULTS: Non-invasive cardiovascular and sudomotor testing allows the assessment of the isolated sympathetic spinal cord in SCI patients. Typical responses are found in relation with the level of the sympathetic lesion. Its definition would allow comparison with the somatic motor and sensory level of lesion of SCI patients and provide additional aid to the classification of those patients. CONCLUSION: For research purposes on the integrity of the spinal sympathetic pathways, a battery of test approach is probably needed, using a combination of stimuli above and below the lesion, evaluating both cardiovascular and sudomotor pathways.

An assessment of the sympathetic function within the hand in patients with carpal tunnel syndrome.

The objective of this study was to assess sympathetic activity within the hand in patients with unilateral carpal tunnel syndrome. In 53 patients, 42 female (79%) and 11 male (21%), having a mean age of 56 years, with clinically and electrophysiologically confirmed unilateral CTS, the sympathetic skin response (SSR) and capillaroscopy examination of the nail folds was obtained for the affected and unaffected hand. Mean values of the SSR parameters did not differ statistically significantly between affected and unaffected hands. Qualitative analysis of the SSR graphs revealed no response in one patient (2%), reduced SSR in seven (13%) and normal SSR in 45 patients (85%). Capillaroscopy showed that the mean diameters of afferent and efferent capillary vessels were not statistically significantly different in the affected and unaffected hand. The results obtained in our study indicate a slight but statistically insignificant effect of the compression of the median nerve on the activity of the sympathetic nervous system in the distribution of this nerve.

Self-reported anxiety, depressive, and vasomotor symptoms: a study of perimenopausal women presenting to a specialized midlife assessment center.

OBJECTIVE: The aim of this study was to examine the association of vasomotor symptoms (VMS) with anxiety and/or depressive symptoms in perimenopausal women. METHODS: A retrospective chart review of 487 women 40 to 64 years old seen during October 2004 to December 2006 in the Women's Midlife Assessment Program at the University of California, Davis, was performed. Of these, 395 women were included in the analysis: 58 (15%) were premenopausal, 199 (50%) were perimenopausal, and 138 (35%) were postmenopausal. VMS bothersomeness was represented by converting Likert-scale ratings for hot flashes and night sweats to scores and adding them into an overall score. Multiple logistic regression models were used to quantify the association of self-reported anxiety and/or depressive symptoms with VMS bothersomeness. RESULTS: Thirty-one (53%) premenopausal, 131 (66%) perimenopausal, and 69 (50%) postmenopausal women reported anxiety and/or depressive symptoms. Perimenopausal and postmenopausal women reporting anxiety and/or depressive symptoms had significantly higher VMS bothersomeness scores (2.2 +/- 1.7 and 2.2 +/- 1.9, respectively) than did women who did not report these symptoms (1.7 +/- 1.7 and 1.6 +/- 1.7, respectively; both P values < 0.05). Women experiencing more bothersome VMS were significantly more likely to report anxiety and/or depressive symptoms (odds ratio, 1.5; P < 0.01). Perimenopausal women were significantly more likely to report anxiety and/or depressive symptoms than were postmenopausal women (odds ratio, 1.9; P < 0.01). Both associations remained significant after restricting the analyses to women not taking hormone therapy or psychotropics. CONCLUSIONS: VMS bothersomeness was associated with self-reported anxiety and/or depressive symptoms, showing the importance of screening for anxiety and mood changes during perimenopause.

Sweat production and the sympathetic skin response: improving the clinical assessment of autonomic function.

The aim of this project was to establish the relationship between sweat production and the electrodermal events comprising the sympathetic skin response to arousal stimuli. A series of randomly timed magnetic stimuli were applied to the neck of healthy human volunteers. Sympathetic skin responses and the associated sweat responses were recorded from the palms of both hands. Sympathetic skin responses typically had a biphasic shape consisting of a negative initial potential (palm relative to dorsum of hand) followed by a positive deflection. Sweat production was positively correlated with amplitude of the second positive deflection of the sympathetic skin response and negatively correlated with the amplitude of the initial negative deflection. For subjects showing only an initial negative sympathetic skin response, sweat release was low or not detectable. During habituation, the negative initial wave increased relative to the second positive wave, and sweat production fell. The strong correlation between the positive wave of the sympathetic skin response and sweat production suggests that the former may provide a quantitative functional measure of sudomotor activity in situations when it is impractical to measure the amount of sweat produced in the startle response. Thus, the positive component of the biphasic sympathetic skin response may be employed in clinical assessment of the functional efficacy of the sympathetic sudomotor system.

Thermometry and calorimetry assessment of sweat response during exercise in the heat.

Our objective was to characterise sweat rate responses in a hot environment during rest and subsequent increasing levels of exercise in relation to thermometrically (i.e., rectal, tympanic, mean skin and mean body temperatures) and calorimetrically derived (i.e., change in body heat storage) thermal parameters. Ten healthy males volunteered and entered an environmental chamber set at 42 degrees C. Participants rested seated during their first hour inside the chamber. Thereafter, they exercised to volitional exhaustion on a cycle ergometer at 20 W with step increments of 20 W h(-1). Across time, fluctuations in sweat rate were systematically associated with similar fluctuations in the integral of body heat storage (t = 13.16, P < 0.001), but not rectal (t = 0.98, P > 0.05), tympanic (t = 0.81, P > 0.05), mean skin (t = 0.12, P > 0.05), or mean body (t = 0.93, P > 0.05) temperatures. In addition, 95% limits of agreement and regression analyses showed that the changes in sweat rate demonstrated the highest agreement and strongest associations with changes in the integral of body heat storage. It is concluded that in a hot environment during rest and subsequent increasing levels of exercise sweat rate is associated with the cumulative changes in the rate of body heat storage.

Effect of posture on the thermal efficiency of a plastic bag wrapping in neonate: assessment using a thermal "sweating" mannequin.

To assess the various heat exchanges with the environment a multisegment, anthropometric, thermal mannequin representing a neonate with a birth weight of 900 g has been designed. The mannequin simulates not only dry heat loss (radiative+conductive+convective body heat exchanges) but also the evaporative skin water loss which can be encountered in low-birth-weight neonates. The model was placed in the supine or prone position in a closed incubator (air temperature, 33 C; relative air humidity, 50%; air velocity below 0.1 m s(-1)). Experiments were performed with the mannequin either naked or wrapped in a flexible, plastic bag (with the head exposed) used to prevent excessive body water loss at delivery and during the following hours About 30% of the model's total surface was wetted with water. Our results demonstrated that body position does not modify dry and evaporative heat losses, whatever the experimental conditions. The plastic bag acts rapidly and reduces total heat loss by 30% to 34%, primarily through a reduction in evaporative water loss (between 5.4 and 6.7 g kg(-1) h(-1)). When the bag is present, the uncovered surface of the head accounts for about 50% of the total heat loss. This simple and inexpensive solution can be used to prevent thermal stress and dehydration in very small premature neonates.

Aerobic energy cost and sensation responses during submaximal running exercise--positive effects of wearing compression tights.

This study aimed to examine the effects of wearing compression compared to classic elastic tights and conventional shorts (control trial) on oxygen cost and sensation responses during submaximal running exercise. In part I, aerobic energy cost was evaluated in six trained runners at 10, 12, 14, and 16 km x h(-1). In part II, the increase in energy cost over time (i. e., slow component expressed as difference in VO2 values between min 2 and end-exercise) was determined in six trained runners at a constant running pace corresponding to 80% of maximal VO2 for 15 min duration. All tests were performed on a 200-m indoor track with equivalent thermal stress conditions. VO2 was determined with a portable metabolic system (Cosmed K4b2, Rome, Italy) during all testing sessions. Runners were asked their ratings of perceived exertion (RPE) and perceptions for clothing sweating, comfort, and whole thermal sensations following each trial. Results showed in part I a significant lower energy cost only at 12 km x h(-1) by wearing compression and elastic tights compared to conventional shorts. During part II, wearing compression tights decreased significantly VO2 slow component by 26 and 36% compared to elastic tights and conventional shorts, respectively. There were no differences in sweating and comfort sensations, RPE, and for whole thermal sensation between clothing conditions in parts I and II. Wearing compression tights during running exercise may enhance overall circulation and decrease muscle oscillation to promote a lower energy expenditure at a given prolonged submaximal speed.

Bedside assessment of sympathetic skin response after spinal cord injury: a brief report comparing inspiratory gasp and visual stimulus.

STUDY DESIGN: A case control study in five controls, and 20 tetraplegic and paraplegic patients, complete and incomplete. OBJECTIVE: The aim was to assess the feasibility of a simple test for sympathetic system preservation after spinal cord damage in a pain-free manner and which could be undertaken worldwide without specialist equipment or manpower. SETTINGS: Patients were attending the Southport Regional Spinal Injuries Centre, England, either as outpatients or as in-patients during rehabilitation. METHODS: The sympathetic skin response (SSR) was recorded on a single-channel ECG recorder from the right hand and right foot in turn after inspiratory gasp (IG) or visual stimulation. RESULTS: Unlike the visually evoked SSR, the gasp-evoked SSR was reliable, albeit of variable amplitude, and there was little difference between the hand and foot. Paraplegics had similar SSRs in the hands as the controls. There was minor insignificant habituation of response for the gasp reflex. There was occasional unexpected SSR distally in patients with complete lesions, and in patients with incomplete lesions the responses could not have been predicted from the sensory motor pattern. CONCLUSIONS: Trained IG induces an SSR which is sufficient to elucidate sympathetic loss following spinal cord injury. It is superior to visual stimulation in this respect. Habituation is not a problem with at least 1 min between tests, and high doses of anticholinergics agents may impair the response.