Clinical autonomic research : official journal of the Clinical Autonomic Research Society
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Randomized Controlled Trial
Normothermic central hypovolemia tolerance reflects hyperthermic tolerance.
To test the hypothesis that those who are highly tolerant to lower body negative pressure (LBNP) while normothermic are also highly tolerant to this challenge while hyperthermic. ⋯ LBNP tolerance while hyperthermic is related to normothermic tolerance and, associated with this finding, those who have a high LBNP tolerance while normothermic remain relatively tolerant when hyperthermic.
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Randomized Controlled Trial
Effect of lowering or restricting sympathectomy levels on compensatory sweating.
There is controversy on whether lowering or restricting the level of sympathectomy can reduce compensatory sweating (CS). This study compared the results from sympathectomies performed to treat severe palmar hyperhidrosis using two distinct levels of T2-4 and T3-4. ⋯ The issue of whether lowering or restricting the level of sympathectomy reduces CS is controversial and needs more supportive evidence. Age may be a predictive factor for severe CS at 6 and 12 months of follow-up. Severe CS is the only known factor that affects patient satisfaction, and family history may also be associated with patient satisfaction.
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Randomized Controlled Trial Clinical Trial
Heart rate variability effects of an agonist or antagonists of the beta-adrenoceptor assessed with scatterplot and sequence analysis.
There is evidence that the processes regulating heart rate variations reflect non-linear complexity and show 'chaotic' determinism. Data analyses using non-linear methods may therefore reveal patterns not apparent with conventional statistical approaches. We have consequently investigated two non-linear methods, the Poincaré plot (scatterplot) and cardiac sequence (quadrant) analysis, and compared these with standard time-domain summary statistics, during a normal volunteer investigation of an agonist and antagonists of the cardiac beta-adrenoceptor. ⋯ The duration of beat-to-beat difference shortened after celiprolol; this contrasted with increased duration of beat-to-beat difference after propranolol and atenolol. These results demonstrated a shift towards sympathetic dominance after the beta-adrenoceptor partial agonist celiprolol contrasting in parasympathetic dominance after the beta-adrenoceptor antagonists propranolol and atenolol. These non-linear methods appear to be valuable tools to investigate HRV in health and in cardiovascular disease and to study the implications of alterations in autonomic control during therapeutic intervention.