Relationships between skin temperature and perfusion in the arm and leg

Summary. Relationships between skin temperature (T_sk) and perfusion have been studied to provide a basis for the use of T_sk in the non-invasive assessment of limb circulation in peripheral vascular disease. Raising the ambient temperature (T_a) from 20 to 30°C increased the perfusion of the glabrous skin of the hands and feet without changing that of the skin of the forearm or calf. On a fractional basis the response in the hand and foot was the same. T_sk was higher in the arms than the legs and in the proximal than distal parts of the limbs. A fall in T_sk was often seen when T_a rose from 20 to 25°C and was attributed to counter-current cooling. Subsequently T_sk rose even in regions where there was no increase in skin perfusion. T_sk can only be related to its perfusion in the fingers, palm and toes. Forearm T_sk was related to the perfusion of the digits. This relationship implies a link with the arterial inflow to the limb which determines the size of its thermal core. Heat conduction from the core seemed important for the skin of areas like the forearm and calf where the constant, low perfusion limited the amount of heat which could be transported to it directly by the blood. The importance of conduction was supported by studies, at T_a 20°C, on subjects during calf muscle exercise and on patients with arterio-venous fistulae. Here an increase in the arterial inflow to the limb was associated with a rise in T_sk of the forearm/calf unrelated to the perfusion of its skin.     

Metabolic and hemodynamic responses to concurrent voluntary arm crank and electrical stimulation leg cycle exercise in quadriplegics.

This study determined the metabolic and hemodynamic responses in eight spinal cord injured (SCI) quadriplegics (C5-C8/T1) performing subpeak arm crank exercise (ACE) alone, subpeak functional electrical stimulation leg cycle exercise (FES-LCE) alone, and subpeak FES-LCE concurrent with subpeak ACE (hybrid exercise). Subjects completed 10 minutes of each exercise mode during which steady-state oxygen uptake (VO2), pulmonary ventilation (VE), heart rate (HR), cardiac output (CO), stroke volume (SV), mean arterial pressure (MAP), arteriovenous oxygen difference (a-v O2 diff), and total peripheral resistance (TPR) were determined. Although mean VO2 for both ACE alone and FES-LCE alone was matched at 0.66 l/mi, individualized power outputs ranged from 0-30 W (mean = 19.4 +/- 1.3) and 0-12.2 W (mean = 2.3 +/- 0.6), respectively. Hybrid exercise elicited significantly higher VO2 (by 54 percent), VE (by 39-53 percent), HR (by 19-33 percent), and CO (by 33-47 percent), and significantly lower TPR (by 21-34 percent) than ACE or FES-LCE performed alone (P less than or equal to 0.05). Stroke volume was similar between hybrid exercise and FES-LCE alone, and these two exercise modes evoked a significantly higher SV (by 41-56 percent) than during ACE alone. These data clearly demonstrate that hybrid exercise creates a higher aerobic metabolic demand and cardiac-volume load in SCI quadriplegics than either subpeak levels of ACE or FES-LCE performed separately. Therefore, hybrid exercise may provide more advantageous central cardiovascular training effects in quadriplegics than either ACE or FES-LCE alone.     

Metabolism in exercising arm vs. leg muscle

Summary. Arm and leg metabolism were compared by arterial and venous catheterization and blood flow measurements (by dye dilution techniques) in two groups of subjects performing 30-min continuous arm or leg exercise of increasing intensity corresponding to approximately 30, 50 and 80% of max oxygen uptake for arm or leg exercise. The absolute work-loads were 2·5-3 times higher during leg compared to arm exercise. Heart rates were the same in both types of exercise. r-Values were 0·97-1·07 during arm exercise. Arterial noradrenaline and adrenaline levels became higher during leg compared to arm exercise (P< 0·05401). Arterial lactate concentration was 50% higher for arm exercise at the two lower intensities (P< 0·001) and the same at the highest intensity compared to leg exercise. Arm lactate release was three times higher (P< 0·01) or the same as leg lactate output at corresponding exercise intensities. Arm and leg glucose uptake during exercise were of the same magnitude at the lower intensities. In contrast to the leg substrate exchange, arm lactate output was higher than the simultaneous glucose uptake (P< 0·05–0·001), indicating a relatively higher rate of glycogen degradation. In conclusion, exercising arm compared to leg muscles working at the same relative intensities utilize more carbohydrate, mainly muscle glycogen resulting in higher lactate release by the exercising extremity. This cannot solely be explained on the basis of differences in the degree of training and occurs with lower catecholamine levels compared to leg exercise.     

Comparison of glutamate-evoked pain between the temporalis and masseter muscles in men and women

Pain in myofascial temporomandibular disorder (TMD) can affect both the masseter and temporalis muscles. Glutamate injection into the masseter muscle evokes pain that is greater in men than in women and this pain is attenuated by co-injection of the N-methyl-d-aspartate (NMDA) receptor antagonist ketamine (10 mmol/L) in men. Animal studies suggested that pain induced by peripheral NMDA receptor activation could differ between the temporalis and masseter muscles and between men and women. The study aims were to investigate differences in glutamate-evoked pain between these muscles and the effectiveness of ketamine to attenuate glutamate-evoked pain in both genders. Pain and mechanical sensitivity were induced in 2 sessions of an experiment in 14 women and 16 men by repeated injections of glutamate (0.5 mol/L) with and without ketamine (20 mmol/L) into the masseter and temporalis muscles. Two injections were applied into the same masseter muscle and 2 injections into the same anterior temporalis muscle at each session. Visual analogue scale (VAS) pain intensities and pain drawing areas were assessed. Glutamate-evoked pain and pain drawing area were significantly greater from the temporalis muscle than from the masseter muscle (P<.02) in both genders. Women reported significantly greater glutamate-evoked masseter muscle pain than men (P<.03). Co-injection of ketamine, at higher dose than previously used, was equally effective in attenuating glutamate-evoked pain from both muscles in both genders (P<.01). The current findings indicate that the characteristics of pain generated by intramuscular injection of glutamate vary for different masticatory muscles and may be partially generated through activation of peripheral NMDA receptors.     

Comparison between men and women admitted to an inpatient rehabilitation unit after cardiac surgery

OBJECTIVE: To determine whether there are differences in several factors between men and women who undergo inpatient post-cardiac surgery rehabilitation. DESIGN: A retrospective chart review. Information was collected on a variety of factors: age; previous myocardial infarction; number of days from surgery to admission to rehabilitation; postsurgery, prerehabilitation complications; length of stay on the rehabilitation unit; living arrangements before surgery; disposition; and postdischarge recommendations. SETTING: Community hospital rehabilitation unit associated with a university hospital. PATIENTS: One hundred thirty-eight patients (54 men, 84 women) admitted to an inpatient rehabilitation unit after cardiac surgery. RESULTS: There was a significant relationship between sex and preadmission living arrangements; 56% of women lived alone versus 26% of men (p < .01). There was a statistically significant difference in length of stay on the rehabilitation unit (p < .02). Men stayed longer, with a median stay of 16 days (95% confidence interval, 15 to 20) versus 15 days for women (95% confidence interval, 14 to 15). Ninety-three percent of men were discharged from rehabilitation at 30 days versus 98% of women. No relationship was noted between men and women in age, previous myocardial infarction, number of days from surgery to rehabilitation admission, length of stay on the rehabilitation unit, postsurgery-prerehabilitation complications, complications on the rehabilitation unit, presurgery living arrangements, disposition, and postdischarge therapy recommendations. CONCLUSION: Men and women showed comparable courses after cardiac surgery. Before surgery, women lived alone more frequently than men.     

Differences between men and women in anxiety early after acute myocardial infarction.

BACKGROUND: Anxiety after acute myocardial infarction influences both short- and long-term recovery. Therefore, determining specific subgroups of patients who have relatively higher anxiety levels is important. Published findings about gender differences in anxiety after acute myocardial infarction are conflicting. OBJECTIVES: To determine whether gender differences in anxiety after acute myocardial infarction exist and whether any of the sociodemographic and clinical variables that often differ between men and women with acute myocardial infarction interact with gender to influence anxiety. METHODS: A total of 424 patients with confirmed acute myocardial infarction were enrolled in this multicenter prospective study. Patients' anxiety level was measured within 72 hours of their arrival at the hospital by using the State Anxiety Inventory and the Brief Symptom Inventory. RESULTS: Women had significantly higher anxiety than did men according to both the State Anxiety Inventory (42 +/- 12.9 vs 37.7 +/- 12.5; P = .001) and the Brief Symptom Inventory (0.83 +/- 0.97 vs 0.63 +/- 0.71; P = .02). Of the sociodemographic and clinical variables examined, only marital status and income significantly interacted with gender to influence anxiety. Married women had higher anxiety than did single and widowed women, and married men had lower anxiety than did single men. Women with lower income had higher anxiety than did women with higher income; income was not related to anxiety in men. CONCLUSION: Women report significantly greater anxiety early after acute myocardial infarction than men do. Women's greater anxiety may be partially explained by marital status and lower income at the time of the infarction.     

The clinical use of supine left lateral leg cycle ergometry for exercise electrocardiographic testing in women, as used in exercise echocardiography.

BACKGROUND: Two-dimensional exercise echocardiography is commonly performed in the supine (SUP) left lateral posture (SLL) to optimize imaging quality. OBJECTIVES: To assess the clinical use of SLL cycle ergometry, we determined the metabolic, cardiovascular, and hemodynamic responses during graded leg cycle ergometry in women, performed in SLL, commonly used during exercise echocardiography, and compared our findings with those obtained during upright (UP) and SUP leg cycle ergometry. METHODS: A total of 21 apparently healthy women performed leg cycle ergometry in 3 distinct postures (UP, SUP, and SLL). RESULTS: Peak oxygen consumption and peak achieved workload during SLL cycle ergometry were significantly lower compared with UP cycle ergometry, indicating that in SLL physical work capacity would be underestimated compared with that obtained for the UP and SUP postures. The peak heart rate was significantly lower in SLL and the peak systolic blood pressure higher, compared with UP. Maximal rate pressure product was not significantly different among the postures, indicating the equivalent value of SLL with regard to augmenting myocardial oxygen demand during exercise. Stroke volume (calculated from aortic Doppler flow integral) was higher at rest, and increased to a smaller extent during exercise, in the SUP posture and SLL compared with UP. Similar peak values were attained for the 3 postures. CONCLUSIONS: SLL is not a suitable modality for the assessment of functional status or for the derivation of target heart rates for exercise training in UP posture. However, SLL leg cycle ergometry exercise provokes a comparable stimulus for the detection of coronary artery disease, as it will increase myocardial oxygen demand to the same extent as UP leg cycle exercise.     

The difference in blood pressure between upper arm and finger during physical exercise

Summary. A new apparatus which measures the blood pressure in the finger continuously and yet not invasively was tested for its usefulness during exercise. It was compared with upper arm measurements in 23 volunteers during prolonged bicycle ergometry. Simultaneously, a pulse plethysmogram was recorded from another finger of the same arm, whereas in six additional volunteers Doppler measurements were carried out on the radial artery. The results show that finger systolic pressure ceased to rise at about 40% of maximal exercise; the difference with the continuously rising systolic pressure in the upper arm becoming significant at 140 W. At the same time the amplitude of the finger plethysmogram became significantly higher than its initial value, indicating distinct cutaneous vasodilation, whereas the volunteers also became hot and started to perspire. However, the radial artery ‘flow’, deduced from the Doppler measurements, did not change significantly during exercise. It increased sharply and markedly in the cooling down period. Simultaneously with this increase in flow, HR and both systolic blood pressures fell drastically whereas the plethysmography amplitude remained about stable at its raised level. The results fit in with the idea that a compromise is achieved between the need for muscle activity and the need for temperature regulation. It is concluded that the Finapres functions well during exercise, but that the systolic pressure in the finger is not representative for its more central counterpart during cutaneous vasodilation. It is argued that opening up of AVAs may contribute to this pressure effect.     

Relationships between exercise self-definitions and exercise participation among urban women in primary care

Exercising prevents the development of coronary artery disease and reduces the incidence of cardiovascular risk factors; however, the mechanisms that underlie participation in an exercise program are not well understood. On the basis of theories of the self, we hypothesized that exercise self-definitions would be significantly related to exercise participation and that such definitions would increase over time. The study sample consisted of 192 middle-aged to older women who were leading a mostly sedentary life and the majority had at least one cardiovascular risk factor. Exercise participation was defined as the number of exercise sessions completed at 8 and 24 weeks. We found an interesting pattern of significant relationships between exercise definitions and exercise participation. Six-month scores were significantly higher than baseline scores, suggesting that exercise self-definitions strengthened over time. If this result is found to be supported in future studies, nurses may want to consider assessing self-definitions when helping patients initiate and maintain an exercise program.     

Effect of aminophylline on plasma and urinary catecholamine levels during heavy leg exercise in healthy young men

1. Methylxanthines have been shown to elevate the basal plasma level and/or urinary excretion of noradrenaline (NA) and adrenaline (ADR) in healthy subjects. The present study addressed the hypothesis that the methylxanthine aminophylline also augments plasma and urinary catecholamines during increased sympathoadrenal activity. 2. Eleven healthy young men performed a maximal 2 h bicycle exercise twice, after double-blind intravenous administration of placebo or aminophylline. Femoral venous plasma and urinary concentrations of NA and ADR were analysed in samples representing basal state, exercise and recovery, using liquid chromatography with electrochemical detection. 3. Leg exercise induced eight- and six-fold increases in the plasma concentrations of NA and ADR, respectively, and seven- and four-fold increases in the urinary concentrations of NA and ADR, respectively, indicating that sympathoadrenal activity was considerably elevated. 4. After aminophylline (mean plasma concentration 20-35 mumol/l), the plasma concentrations of NA (P less than 0.001) and ADR (P less than 0.05) were independently higher at rest, during exercise and during recovery, in comparison to after placebo; the mean exercise plasma level of NA was increased by the drug from 13 +/- 1 to 21 +/- 2 nmol/l and the corresponding level of ADR from 2.1 +/- 0.4 to 2.9 +/- 0.5 nmol/l. Also urinary NA (P less than 0.01) and ADR (P less than 0.05) were elevated by aminophylline; the exercise concentrations of NA in the urine were 75 +/- 8 and 97 +/- 10 mumol/mol of creatinine after placebo and aminophylline, respectively, and the corresponding levels of ADR were 12 +/- 3 and 16 +/- 3 mumol/mol of creatinine, respectively.     

Effect of exercise on plasma atrial natriuretic factor and cardiac function in men and women

In order to provide an integrated view of the physiology of atrial natriuretic factor (ANF) during exercise, we studied changes of its plasma concentrations in 13 normal subjects (seven males, six females) during three graded exercise levels and two periods of recovery (5 and 30 min), concomitantly with an assessment of cardiac function and ventricular volumes by multigated radionuclide angiography. Mean ANF levels (+/- SEM) increased in all patients at the second (P less than 0.002) and third (P less than 0.002) exercise levels, and after 5-min recovery (P less than 0.01): in males from 16 +/- 7 to 30 +/- 11 pg ml-1 at the third level, in females from 27 +/- 12 to 61 +/- 33 pg ml-1. Normal values were observed after 30-min recovery. Even if mean ANF levels were all higher in females, this difference did not reach statistical significance (P = 0.06). Significant decreases of ventricular volumes, as well as increases of ejection fraction and rate pressure product, were noted during exercise and were similar in both sexes. The kinetics of plasma ANF concentrations, compared with the increase of rate pressure product, was characterized by a latency and a remanence in recovery. This remanence, also present in the changes of ventricular volumes, supports the hypothesis that other factor(s) like catecholamines might still exert their influence after the exercise stops.     

首次体外受精胚胎移植夫妇术前心理应激状态的比较

目的:探讨首次体外受精-胚胎移植(in vitro fertilization and embryo transfer,IVF-ET)夫妇术前心理应激状况。方法:入选首次行IVF-ET的278对夫妇,于进入治疗周期前(30±1)d进行压力感知量表(perceived stress scale,PSS)、抑郁自评量表(self-rating depression scale,SDS)、焦虑自评量表(self-rating anxiety scale,SAS)和事件影响量表修订版(impact of event scale-revised,IES-R)测量,对比男性和女性的压力感知、抑郁、焦虑和创伤应激症状。结果:首次接受IVF-ET治疗的夫妇术前女性、男性抑郁症状检出率分别为28.8%、31.3%,焦虑症状检出率分别为14.4%、19.4%,男女间差异无统计学意义;术前女性、男性IVF-ET治疗相关的创伤应激症状检出率分别为58.3%、47.5%,女性高于男性(P0.05)。男性和女性患者的焦虑、抑郁和压力感知评分均高于常模(P0.05),男女性间差异无统计学意义。女性患者IVF-ET治疗相关的创伤应激症状评分为(23.1±13.1)分,高于男性[(20.5±13.1)分,P0.05]。结论:首次接受IVF-ET治疗的夫妇术前双方心理应激水平均升高;男性和女性压力感知、抑郁和焦虑症状相似,女性IVF-ET治疗相关的创伤应激症状更显著,需采取针对性处理。     

Differences in carotid artery wall properties between presumed-healthy men and women

The vessel wall properties of the common carotid artery were noninvasively studied in 109 normotensive, presumed normal male and female volunteers of various ages (20-69 y) with the use of a multi-gate pulsed Doppler system. This system allows the on-line recording of velocity profiles and the relative changes in carotid artery diameter during the cardiac cycle (delta d/d). From the width of these profiles the systolic internal diameter (d) of the carotid artery can be determined. With the use of d, the maximal increase in delta d/d during systole and the pulse pressure, as measured in the brachial artery (delta p), the distensibility coefficient and the cross-sectional compliance were calculated. Both distensibility and cross-sectional compliance were significantly lower in females than in males, irrespective of age. This likely results from a stiffer arterial wall behavior in females, because the relative increase in vessel diameter during the cardiac cycle is lower in females than in males, despite the fact that their pulse pressure values are not significantly different. The carotid artery diameters were similar in men and women. The findings in the present study indicate that the common carotid artery is stiffer in females than in males of comparable age. Therefore, sex-dependent differences have to be considered in the interpretation of arterial distensibility and cross-sectional compliance.