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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Post-operative fatigue is an important subjective problem for surgical patients, but its basis is unknown, and the possibility of a psychological component has been neglected. To investigate its putative physiological and psychological bases, 74 patients undergoing coronary artery bypass graft surgery were studied. Circulating catecholamine levels were measured at intervals perioperatively and questionnaires were used to measure fatigue, depression and anxiety up to 30 days post-operatively. We tested whether fatigue was related either to the catecholamine or to the emotional responses to surgery. The second element to the design was a controlled randomized study: patients underwent different forms of psychological preparation or a no-treatment control procedure in an attempt to test whether post-operative fatigue was amenable to psychological manipulation. Psychological preparation had no effect. Fatigue at 30 days was greatest in patients whose noradrenaline levels were greatest perioperatively. Independently of this relationship, fatigue at 30 days correlated with concurrent levels of depression and anxiety. Post-operative fatigue has both physiological and psychological correlates.
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PMID:Post-operative fatigue following coronary artery bypass surgery: relationship to emotional state and to the catecholamine response to surgery. 799 68

The authors examined clinically 1710 women. Among them 199 women with symptoms of menopause were selected and divided into two groups: group I (control) included 80 women without contact with carbon disulphide and group II (examined) included 119 women chronically exposed to carbon disulphide at a concentration of 9.36-23.4 mg/m3. Menopause was present in 16.59% of women chronically exposed to CS2 as compared with 8.05% of the normal population. The mean age at menopause was 48.1 years in group I and 43.9 in group II. Significantly more frequent headaches, weight gain and loss of libido (p < 0.01) were observed in women chronically exposed to CS2. While in the control group fatigue, palpitations and hot flushes were more often (p < 0.001). The concentrations of estrone (p < 0.01), estradiol, progesterone, 17-hydroxy-progesterone, testosterone and dehydroepiandrosterone sulphate (DHAS) were significantly decreased in women chronically exposed to CS2 (p < 0.001). No difference in the level of dehydroepiandrosterone was found. The daily excretion of adrenaline and noradrenaline in urine and concentrations of dopamine in plasma of women chronically exposed to CS2 were lower (p < 0.001), while the concentrations of serotonin and prolactin in plasma were higher (p < 0.001). No differences in the level of FSH or LH were noted between the two groups. Significant negative linear correlations between serotonin and FSH (r = -0.45; p < 0.01) serotonin and daily excretion of adrenalin (r = -0.43; p < 0.01) or noradrenalin (r = -0.58; p < 0.001) were found in the exposed group.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Effect of carbon disulfide on menopause in women]. 799 46

Six healthy males, the EMSInauts, were isolated in hyperbaric chambers for a period of 28 days at 5-msw overpressure. During that period they had to carry out meaningful operational and research tasks in addition to monitoring their psychological and physiological reactions. The actual workload was evaluated and compared with the planned workload, and its effects on symptomatology and psychobiology. The perceived workload and its effects on psychosomatic symptomatology and on some biological indices were monitored. Thus it was possible to evaluate how the workload carried during 4 weeks of isolation affected the psychological and biological well-being of the six EMSInauts. The following three types of assessments were performed: 1. Workload assessment: The objective workload was calculated based on the schedule which was revised daily, and the actual load calculated by the commander. A workload questionnaire was administered daily after each working session. 2. Psychosomatic assessment: Morning and evening questionnaires were administered daily. The state of health and of anxiety were also evaluated. 3. Biological indices: Cortisol, testosterone, adrenalin, and noradrenaline were determined once a week. In addition, cardiac activity was monitored every day. The workload assessment showed that on the average the planned workload was accomplished in slightly less than the scheduled time. The workload was not perceived as severe in terms of cognitive, emotional, and physical load. The group rated the support received from each other and from the mission control personnel as average, with minor changes during the isolation period. They gave a high rating to the amount of control they had over their activities. Fatigue and tension were scored in the middle range. The psychosomatic assessment showed that there were few symptoms, and these were mostly of low severity. The most common symptom was general fatigue. Furthermore, minor dizziness, headache and light tremor was in some cases reported. The sleep quality was good, but complaints about poor sleep increased somewhat with the passing of time. Few and mostly minor health problems were experienced during isolation. Only one EMSInaut had to miss one day of work due to a bout of flu. The state of anxiety was below that of the general population throughout the isolation period. The biological indices used showed no evidence of stress from the workload handled during the isolation period. The level of the "stress hormone" cortisol actually decreased during isolation. The adrenalin excretion, which tends to go up during acute stress, remained unchanged during this period. Neither was there any evidence of changes in cardiac activity throughout the isolation period.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:European isolation and confinement study. Workload and stress: effects on psychosomatic and psychobiological reaction patterns. 816 54

Fifteen female nurses, aged between 21 and 29 years and employed in an intensive care unit, were examined with the aim of evaluating their psychophysical adaptation to one of the most commonly used, rapidly rotating shift systems, the "metropolitan rota" (2-2-2-2), with the length of the shifts modified according to the work load (including night shifts of 10h) and with the start of the morning shift delayed (to 7 a.m.). Subjective evaluations of work load and psycho-physical conditions as well as performance measures (reaction time, search and memory test), blood pressure and heart rate were recorded at the start, middle and end of the work shifts on the last 4 days of the shift cycle, comprising one morning, one afternoon and two consecutive nights. During the shifts, plasma cortisol and urinary excretion rate of 6-sulphatoxymelatonin, adrenaline and noradrenaline were also recorded, as well as oral temperature and activity-sleep logs. The results showed that this rapidly rotating shift system including two consecutive night shifts does not significantly alter the normal circadian rhythms of the body, particularly as concerns performance levels, body temperature and hormone excretion. Moreover, the lengthening of the night shift to 10h can be considered acceptable in terms of work efficiency, provided that work load is reduced and there are sufficient rest pauses available to compensate for tiredness and sleepiness. On the other hand, the shortening of the day shifts to 7h and the delayed start of the morning shift to 7 a.m. appeared convenient in relation to both work load and sleep duration.
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PMID:Evaluation of a rapidly rotating shift system for tolerance of nurses to nightwork. 817 85

To determine if exercise intolerance and fatigue in chronic heart failure could be exacerbated by an abnormal metabolic response to exercise, we studied 12 patients with stable chronic heart failure and 12 normal volunteers during symptom-limited maximal treadmill exercise. Peak VO2 was 17.2 (15.1-19.2) ml.kg-1 x min-1 in patients and 29.9 (26.3-33.5) in controls (mean and 95% confidence intervals; P < 0.0001, t-test). Overall, levels in peripheral venous blood of glucose, glycerol and free fatty acids were greater in patients, although the differences became less marked with increasing exercise intensity. Noradrenaline was elevated in patients at rest, but the peak exercise response was similar to controls. Responses of adrenaline, insulin and glucagon were similar in both groups. We conclude that depletion of the levels of circulating substrates is not contributory to exercise intolerance and fatigue in chronic heart failure. Greater levels of glycerol and free fatty acids may be mediated by excess sympathetic nervous system activity, reflected in elevated noradrenaline levels.
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PMID:Metabolic responses to graded exercise in chronic heart failure. 829 29

Physical exercise influences the central dopaminergic, noradrenergic and serotonergic systems. A number of studies have examined brain noradrenaline (norepinephrine), serotonin (5-hydroxytryptamine; 5-HT) and dopamine with exercise. Although there are great discrepancies in experimental protocols, the results indicate that there is evidence in favour of changes in synthesis and metabolism of monoamines during exercise. There is a possibility that the interactions between brain neurotransmitters and their specific receptors could play a role in the onset of fatigue during prolonged exercise. The data on the effects of branched chain amino acid (BCAA) supplementation and 'central fatigue' seem to be conflicting, although recent studies suggest that BCAA supplementation has no influence on endurance performance. There are numerous levels at which central neurotransmitters can affect motor behaviour; from sensory perception, and sensory-motor integration, to motor effector mechanisms. However, the crucial point is whether or not the changes in neurotransmitter levels trigger or reflect changes in monoamine release. Until recently most studies were done on homogenised tissue, which gives no indication of the dynamic release of neurotransmitters in the extracellular space of living organisms. Recently, new techniques such as microdialysis are voltammetry were introduced to measure in vivo release of neurotransmitters. Microdialysis can collect virtually any substance from the brain of a freely moving animal with a limited amount of tissue trauma. This method allows measurement of local neurotransmitter release during on-going behavioural changes such as exercise. The results of the first studies using these methods indicate that the release of most neurotransmitters is influenced by exercise. Although the few studies that have been published to date show some discrepancies, we feel that these recently developed and more sophisticated in vivo methods will improve our insight into the relationship between the monoamine and other transmitters during exercise. Continued quantitative and qualitative research needs to be conducted so that a further understanding of the effects of exercise on brain neurotransmission can be gained.
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PMID:Exercise and brain neurotransmission. 857 Oct

Aging is a physiological process that shares many behavioral, biochemical and neuroendocrine phenomena with the pathophysiological situation of unresolved stress, as well as with a pharmacologically induced syndrome resulting from chronic benzodiazepine (BZ) consumption. Behavioral findings include symptoms such as drowsiness, ataxia, fatigue, confusion, weakness, dizziness, vertigo, syncope, reversible dementia, depression, impairment of intellectual, psychomotor and sexual function, agitation, auditory and visual hallucinations, paranoid ideation, panic, delirium, depersonalization, sleepwalking, aggressivity, orthostatic hypotension, and insomnia. Neuroendocrine findings include: central depletion of noradrenaline (NA), dopamine, adrenaline (AD), and serotonin (5-HT); reduction in the ratio of circulating NA/AD as well as platelet 5-HT and increase of AD, plasma free 5-HT and cortisol. These disturbances together with the increased platelet aggregability observed in the three groups are typical of unresolved-stress situations. Immunological findings include significant reduction of peripheral T lymphocytes (CD3, CD4, CD8) and the CD4/CD8 ratio, CD16 and gamma-delta cells. On the other hand, the three groups (elderly subjects, subjects faced with unresolved stress, and BZ consumers) show increase of the CD57 lymphocyte subset as well as natural killer cytotoxicity. Alterations of several biological markers have also been found, specifically in the oral glucose tolerance test, the intramuscular clonidine test, and the supine/orthostasis/exercise test. From a clinical point of view, the three groups appear to be more susceptible to the appearance and progression of many acute and chronic diseases (infectious and malignant diseases). As a result, chronic consumption of BZs should be avoided in both the elderly and subjects in unresolved-stress situations.
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PMID:Benzodiazepines: tolerability in elderly patients. 884 97

To investigate how the pituitary-adrenal and sympathetic nervous hormones change in psychologically exhaustive states following an ultraendurance race, the Profile of Mood States (POMS), plasma ACTH, beta-endorphin, adrenaline, noradrenaline, and serum cortisol were measured in 29 male athletes two days before, immediately after, and one day after a triathlon. Psychological exhaustion was defined as possessing low POMS vigour and high fatigue immediately post-race. Eleven subjects met the criteria for the exhaustive group, and another ten were placed in the vigour group, which possessed high vigour regardless of fatigue score and the remaining eight subjects were excluded from analysis because they did not satisfy experimental protocol. Student's t-tests revealed no significant group differences in age, race time, pre-race POMS and hormone values. Immediately post-race, serum cortisol and plasma adrenaline did not differ between groups. However, significantly lower levels of plasma beta-endorphin (p = 0.03) and noradrenaline (p = 0.05), and relatively lower levels of plasma ACTH (P = 0.08) immediately post-race were observed in the exhaustive group when compared with the vigour group. We conclude that pituitary and sympathetic nervous hormone reactivity is attenuated following ultraendurance race in athletes showing psychological exhaustion and this is independent of race performance.
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PMID:Relationships between exhaustive mood state and changes in stress hormones following an ultraendurance race. 885 2

1. Our aim was to determine if sympathetic vasodilatation occurs in the human forearm, and if the vasodilating substance nitric oxide contributes to this dilatation. We also sought to determine if the nitric oxide might be released as a result of cholinergic stimulation of the vascular endothelium. 2. Blood flow was measured in the resting non-dominant forearm with venous occlusion plethysmography. To increase sympathetic traffic to the resting forearm, rhythmic handgrip exercise to fatigue followed by post-exercise ischaemia was performed by the dominant forearm. A brachial artery catheter in the non-dominant arm was used to selectively infuse drugs. 3. During control conditions, there was mild vasodilatation in the resting forearm during exercise followed by constriction during post-exercise ischaemia. When exercise was performed after brachial artery administration of bretylium (to block noradrenaline release) and phentolamine (an alpha-adrenergic antagonist), profound vasodilatation was seen in the resting forearm during both exercise and post-exercise ischaemia. 4. When the nitric oxide synthase blocker NG-monomethyl-L-arginine (L-NMMA) was administered in the presence of bretylium and phentolamine prior to another bout of handgripping, little or no vasodilatation was seen either during exercise or post-exercise ischaemia. Atropine also blunted the vasodilator responses to exercise and post-exercise ischaemia after bretylium and phentolamine. 5. These results support the existence of active sympathetic vasodilatation in the human forearm and the involvement of nitric oxide in this phenomenon. They also suggest nitric oxide might be released as a result of cholinergic stimulation of the vascular endothelium.
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PMID:Evidence for nitric oxide-mediated sympathetic forearm vasodiolatation in humans. 903

1. We studied the mechanism of insulin-mediated attenuation of noradrenaline-induced vasoconstriction in mesenteric resistance arteries (approximately 210 microns diameter) from 10-week-old male Wistar rats (n = 10; weight 321 +/- 11 g). Exposure to physiological concentrations of insulin (50 m-units/l) significantly blunted the contractile response to noradrenaline over the concentration range 3 x 10(-6) to 3 x 10(-5) mol/l (16 vessels; 13.1 +/- 4.3% reduction in maximum tension at 3 x 10(-5) mol/l noradrenaline; P < 0.01 versus no insulin). 2. This effect of insulin was prevented by the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (10(-4) mol/l; 16 vessels; 3.3 +/- 9.1% reduction in maximum tension; P = 0.8 versus no insulin). There was no evidence of fatigue in four noradrenaline dose-response curves for 16 control vessels in the absence of insulin and NG-nitro-L-arginine methyl ester (P = 0.8; first versus second dose-response curve). With L-arginine present in the incubation medium, insulin again attenuated the noradrenaline-induced vasoconstriction (10.7 +/- 3.2% reduction in tension; P = 0.02 versus L-arginine and no insulin; P = not significant versus insulin and no L-arginine). 3. Endothelium-dependent relaxation was initially confirmed in all vessels by demonstrating normal acetylcholine- (5.4 x 10(-7) to 1.1 x 10(-4) mol/l) induced vasodilatation in vessels preconstricted with noradrenaline (6 x 10(-6) mol/l) in the absence of NG-nitro-L-arginine methyl ester, L-arginine and insulin (P = not significant between the different groups of vessels). 4. We conclude that insulin attenuates noradrenaline-induced vasoconstriction in resistance arteries by stimulation of nitric oxide release. Abnormal insulin-stimulated nitric oxide release could be of relevance in the pathogenesis of hypertension and diabetic microvascular disease.
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PMID:Insulin-induced attenuation of noradrenaline-mediated vasoconstriction in resistance arteries from Wistar rats is nitric oxide dependent. 905 15


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