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Comparison of the reluctance of house staff of metropolitan and suburban hospitals to perform mouth-to-mouth resuscitation.

BACKGROUND: Although performing mouth-to-mouth resuscitation (MMR) during cardiopulmonary resuscitation (CPR) is an effective lifesaving procedure, both the general public and physicians are often unwilling to perform CPR. Fear of contracting infectious diseases, especially AIDS, is often stated as the reason for this reluctance. However, the likelihood of saving a life usually outweighs the chance of contracting an infectious disease, especially when victims are considered to be at low risk for being HIV+ and are in communities with low incidences of HIV antibodies. METHODS: The entire housestaff (58 residents) in the Department of Internal Medicine of a suburban hospital responded to a questionnaire of hypothetical cardiac arrest scenarios in both inpatient and outpatient settings. Their responses were compared to those previously obtained from the housestaff (82 residents) of a hospital in a large metropolitan area with a high incidence of HIV positive patients. RESULTS: The willingness of the suburban housestaff (residents) to perform MMR in the inpatient scenario of a patient with an unknown risk for communicable infections was 43%, with trauma was 12%, with a perceived high risk for being HIV+ was 14%, and in the elderly was 29%, compared to 45, 16, 7 and 39%, respectively of the house staff of the metropolitan hospital. In outpatient scenarios, the willingness of the suburban housestaff to perform MMR on a victim with an unknown risk for communicable infections was 50%, with trauma was 33%, with a perceived high risk for being HIV+ was 34%, in the elderly was 26%, and in a child was 86%, compared to 54, 36, 21, 65, and 99%, respectively, of the metropolitan residents. Overall, the suburban male residents were more likely to be willing to perform MMR than the female ones, as were residents actively practising a religion or having graduated from medical schools in the United States. Suburban residents under 30 years of age seemed more willing to perform MMR in the majority of the scenarios than those over 30 years of age. Of the 31 suburban residents that stated they would be unwilling to perform MMR in at least one of the given scenarios, all stated that their unwillingness was due to fear of becoming infected with HIV or other infectious agents. In 1994, the percentage of known HIV positive individuals admitted to the suburban hospital was approximately five times less than that of the metropolitan hospital whose house staff was interviewed (P < 0.001). CONCLUSIONS: Patients perceived to be at high risk for HIV were less likely to receive MMR than those at low risk. The reluctance of house staff to perform MMR in a suburban community hospital with a low incidence of HIV+ patients is similar to that of house staff in a large metropolitan community with a much higher incidence of infected patients. This reluctance, which was largely due to fear of contracting HIV infections, is not influenced by frequent contact with patients infected with HIV but is based on perceived rather than actual risks of contracting HIV. To increase the willingness of physicians, other medical personnel, and the lay public to perform MMR on victims of cardiac and respiratory arrests, the negligible risk of contracting infectious diseases while performing MMR should be emphasized. Use of portable barrier masks while performing MMR and an increase in their availability would decrease the minimal risks even further, and is recommended by the authors.

Acquired Immunodeficiency Syndrome↗

Effect of sodium aluminosilicate on phosphorus utilization by chicks and laying hens.

Three experiments were conducted to evaluate the effects of sodium aluminosilicate (SAS) on performance of chicks and laying hens fed diets varying in nonphytate P (NPP), phytate, and fiber content. In two chick growth experiments a corn and soybean meal diet and a phytate and fiber-free casein-dextrose diet were used. These diets contained .1% NPP and 1.1% Ca and were fortified with 0, .05, or .10% P from KH2PO4 and 0 or .5% SAS. A 3 x 2 factorial arrangement of treatments was used. Sodium aluminosilicate supplementation significantly (P less than .05) depressed growth of chicks fed the corn and soybean meal diets containing 0 or .05% supplemental AP. Sodium aluminosilicate addition decreased (P less than .05) tibia ash and total tibia P (tibia weight x P concentration) in both chick experiments, with the effect being greater for chicks fed the corn and soybean meal diet. In the laying hen experiment, birds were fed corn and soybean meal diets containing NPP levels of .1, .45, or 1.8% and SAS levels of 0 or 1.0%. Egg production and egg yield were depressed (P less than .05) by feeding diets containing .1 or 1.8% NPP, and egg specific gravity was decreased (P less than .05) by feeding 1.8% NPP. Addition of SAS to the .1% NPP diet caused a large reduction (P less than .05) in egg production, egg weight, and feed efficiency, whereas SAS supplementation of the 1.8% NPP diet had no significant effect. Sodium aluminosilicate supplementation increased (P less than .05) egg specific gravity for hens fed the .1 and 1.8% NPP diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Aluminum Silicates↗

Effect of addition of a detoxifying agent to laying hen diets containing uncontaminated or Fusarium toxin-contaminated maize on performance of hens and on carryover of zearalenone.

16-wk experiment with laying hens was carried out to examine the effects of feeding of mycotoxin-contaminated maize (CM) on performance, nutrient digestibility, weight of organs, serum chemical parameters, and antibody titers to Newcastle disease virus (NDV) in serum. Also tested were fimbrien antigen K88 in egg yolk and zearalenone (ZON) residues in eggs and tissues. The Fusarium-toxin-contaminated maize contained 17,630 microg deoxynivalenol and 1,580 microg ZON/kg. Moreover, Mycofix Plus (MP), a so-called detoxifying agent, was added to both the uncontaminated control (UCM) and to the CM diet (70% dietary maize inclusion). Each of the four resulting diets (UCM, UCM-MP, CM, CM-MP) was tested on 25 laying hybrids (Lohmann Brown). Feeding of the CM diets significantly depressed feed intake compared to the control groups by approximately 5%. This was mainly due to the effects observed at the beginning of the experiment. Daily egg mass production/hen was 56.6, 58.4, 53.9, and 55.2 g in groups UCM, UCM-MP, CM and CM-MP, respectively. Nutrient digestibility and metabolizability of gross energy were slightly depressed by feeding the CM diets and improved by MP addition. Feeding of the CM diets resulted in a significant decrease in serum titers to NDV and to an increase in yolk titers to antigen K88. No residues of ZON or of its metabolites were found in yolk, albumen, abdominal fat, breast meat, follicles greater than 1 cm in diameter, ovaries including follicles smaller than 1 cm in diameter, magnum, and serum. ZON and alpha-zearalenol (alpha-ZOL) were detected in livers of hens fed the CM diets at mean concentrations of 2.1 and 3.7 microg/kg, respectively. It was concluded that feeding maize which was highly contaminated with Fusarium mycotoxins adversely influenced performance of hens and modulated immune response. At the given level of zearalenone and at the indicated detection limits, no residues of ZON and its metabolites were found in eggs. The effects of the tested detoxifying agent were quite mycotoxin-independent.

Animal Feed↗

Knowledge discovery and data mining to assist natural language understanding.

As natural language processing systems become more frequent in clinical use, methods for interpreting the output of these programs become increasingly important. These methods require the effort of a domain expert, who must build specific queries and rules for interpreting the processor output. Knowledge discovery and data mining tools can be used instead of a domain expert to automatically generate these queries and rules. C5.0, a decision tree generator, was used to create a rule base for a natural language understanding system. A general-purpose natural language processor using this rule base was tested on a set of 200 chest radiograph reports. When a small set of reports, classified by physicians, was used as the training set, the generated rule base performed as well as lay persons, but worse than physicians. When a larger set of reports, using ICD9 coding to classify the set, was used for training the system, the rule base performed worse than the physicians and lay persons. It appears that a larger, more accurate training set is needed to increase performance of the method.

Artificial Intelligence↗

Reluctance of paramedics and emergency medical technicians to perform mouth-to-mouth resuscitation.

Recently, a reluctance of lay and medical personnel to perform mouth-to-mouth resuscitation (MMR) in hospital and community settings has been documented, with 45% of respondents declining to perform MMR on a stranger. In the present study, we examined whether the perceived risk and fear of contracting infectious diseases diminishes the willingness of paramedics and emergency medical technicians (EMTs) to perform MMR. Seventy-seven EMTs and 27 paramedics responded to a questionnaire, administered by one of two physicians, containing mock cardiac arrest scenarios that were designed to assess willingness to perform MMR as a citizen responder. Faced with a situation in which an adult stranger required MMR, 57% of the participating EMTs and all of the paramedics stated that they would refuse to perform MMR. None of the paramedics and only 32.5% of the EMTs stated that they would perform MMR on a man in a gay neighborhood. In addition, 23% of the EMTs and 37% of the paramedics indicated that they would refuse to perform MMR on a child. White respondents were more willing than nonwhite respondents to perform MMR. Twenty-nine percent of the prehospital-care providers had been in situations requiring MMR in the community, and 40% either had walked away or did only external compression. Of those participating paramedics and EMTs who had performed MMR in emergency situations, only 45% indicated that they would do so again. The respondents indicated that they would not be willing to administer MMR because of the fear of contracting infectious agents, especially the human immunodeficiency virus. Despite the proven effectiveness of MMR in saving lives, paramedics and EMTs are highly reluctant to perform MMR as citizen responders. Their perceived risks of contracting infectious agents during MMR are high, despite the low actual risks. We recommend that instruction in cardiopulmonary resuscitation for providers of pre-hospital care, the medical community, and the general public should emphasize the benefits of providing MMR, the actual low risks of contracting infectious diseases during administration of MMR, and the use of widely available and effective barrier masks to minimize any risks due to administration of MMR.

Adult↗

Migraine, chronic tension-type headache, and cluster headache in an Ethiopian rural community.

Fifteen-thousand-five-hundred adults (> or = 20 years) in a rural district in Ethiopia with a population of 250,000 were studied for chronic headache. Door-to-door survey was performed by trained lay health workers using a questionnaire with a high degree or reliability and validity. The 1-year prevalence of migraine headache was 3.0% (4.2% for females and 1.7% for males) with the peak age specific rate in the fourth decade. Migraine headache was about three times more common in females than in males at any decade. Two-thirds of migraine sufferers had rather frequent attacks. The most frequent trigger factors were emotional stress (90%), changes of weather (78%), physical exhaustion (75%), and smell (70%). Migraine with aura was rare. Family occurrence of migraine in first-degree relatives was 30%. The 1-year prevalence of chronic tension-type headache was 1.7%, while cluster headache was found to be extremely rare. Compared to similarly performed surveys, the prevalence of migraine among rural Ethiopians was less than among Nigerian Africans.

Adult↗

Cardiopulmonary resuscitation performed by bystanders does not increase adverse effects as assessed by chest radiography.

UNLABELLED: Important adverse effects of bystander cardiopulmonary resuscitation (CPR) are well known. We describe the number of nonmedical professional CPR-related complications in patients surviving cardiac arrest, as assessed by chest radiograph. Within 2 yr, all consecutive patients admitted to the department of emergency medicine at a university hospital who had a witnessed, nontraumatic, normothermic cardiac arrest were studied. Radiologically evaluated adverse effects were compared with Mann-Whitney U-tests between patients who received bystander basic life support (Bystander group) and patients who did not receive bystander basic life support before advanced life support was started (ALS group). For assessment of bystander CPR-associated complications, chest radiographs were used. Of 224 patients, 173 were eligible. The median age was 58 yr (interquartile range, 51-71 yr), and 126 patients (73%) were men. The incidence of adverse effects associated with assisted-ventilation maneuvers and external chest compressions did not differ significantly between groups (severe gastric insufflation, 17% vs 18% between the Bystander group [n = 59] and the ALS group [n = 96], respectively; suspicion of aspiration, 22% vs 17%, respectively; soft tissue emphysema, 2% vs 1%, respectively; and serial rib fractures, 8% vs 8%, respectively). CPR administered by nonmedical personnel did not increase the number of life support-related adverse effects in patients surviving cardiac arrest as assessed by means of chest radiograph on admission. IMPLICATIONS: Complications related to cardiopulmonary bypass (CPR) are not increased when CPR is administered by nonmedical personnel, as assessed by chest radiograph. These data may be valuable in motivating lay people to perform basic life support.

Aged↗

Efficacy of chest compression-only BLS CPR in the presence of an occluded airway.

Reluctance of the lay public to perform bystander CPR is becoming an increasingly worrisome problem in the USA. Most bystanders who admit such reluctance concede that fear of contagious disease from mouth-to-mouth contact is what keeps them from performing basic life support. Animal models of prehospital cardiac arrest indicates that 24-h survival is essentially as good with chest compression-only CPR as with chest compressions and assisted ventilation. This simpler technique is an attractive alternative strategy for encouraging more bystander participation. Such experimental studies have been criticized as irrelevant however secondary to differences between human and porcine airway mechanics. This study examined the effect of chest compression-only CPR under the worst possible circumstances where the airway was totally occluded. After 6 min of either standard CPR including ventilation with a patent airway or chest compressions-only with a totally occluded airway, no difference in 24 h survival was found (10/10 vs. 9/10). As anticipated arterial blood gases were not as good, but hemodynamics produced were better with chest compression-only CPR (P < 0.05). Chest compression-only CPR, even with a totally occluded airway, is as good as standard CPR for successful outcome following 6.5 min of cardiac arrest. Such a strategy for the first minutes of cardiac arrest, particularly before professional help arrives, has several advantages including increased acceptability to the lay public.

Airway Obstruction↗

Peptide mass fingerprinting peak intensity prediction: extracting knowledge from spectra.

Matrix-assisted laser desorption/ionization-time of flight mass spectrometry has become a valuable tool in proteomics. With the increasing acquisition rate of mass spectrometers, one of the major issues is the development of accurate, efficient and automatic peptide mass fingerprinting (PMF) identification tools. Current tools are mostly based on counting the number of experimental peptide masses matching with theoretical masses. Almost all of them use additional criteria such as isoelectric point, molecular weight, PTMs, taxonomy or enzymatic cleavage rules to enhance prediction performance. However, these identification tools seldom use peak intensities as parameter as there is currently no model predicting the intensities based on the physicochemical properties of peptides. In this work, we used standard datamining methods such as classification and regression methods to find correlations between peak intensities and the properties of the peptides composing a PMF spectrum. These methods were applied on a dataset comprising a series of PMF experiments involving 157 proteins. We found that the C4.5 method gave the more informative results for the classification task (prediction of the presence or absence of a peptide in a spectra) and M5' for the regression methods (prediction of the normalized intensity of a peptide peak). The C4.5 result correctly classified 88% of the theoretical peaks; whereas the M5' peak intensities had a correlation coefficient of 0.6743 with the experimental peak intensities. These methods enabled us to obtain decision and model trees that can be directly used for prediction and identification of PMF results. The work performed permitted to lay the foundations of a method to analyze factors influencing the peak intensity of PMF spectra. A simple extension of this analysis could lead to improve the accuracy of the results by using a larger dataset. Additional peptide characteristics or even PMF experimental parameters can also be taken into account in the datamining process to analyze their influence on the peak intensity. Furthermore, this datamining approach can certainly be extended to the tandem mass spectrometry domain or other mass spectrometry derived methods.

Acrylamide↗

Perception of spatial orientation in spasmodic torticollis. Part 2: The visual vertical.

Twenty-nine patients with idiopathic spasmodic torticollis (ST) and matched normal control subjects were asked to align a target line to perceived earth vertical [visual vertical (VV)]. Settings were made against a whole-field random-dot background that was either stationary or rotating around the line of sight, and subjects performed the task upright and lying horizontally on their sides. Normal subjects were tested both head upright and after assuming a voluntary head tilt. Patients with ST set the VV close to true upright with a minimal deviation toward tilt of the head in contrast to normal subjects assuming a head tilt who set the VV in the opposite direction to the head tilt (Müller "E" effect). Settings against the spinning disk were biased in the direction of rotation similarly for both subject groups. Settings made against static or spinning disk performed when subjects lay horizontally were tilted in the direction of recumbence (Aubert "A" effect) similarly for both subject groups. When attempting to set the target line parallel to the long axis of the face, patients with head tilt set the line to upright, whereas normal subjects correctly estimated their tilts. One hypothesis offered to explain these results is that the patients referenced only their upright trunk for vertical and did not make use of neck proprioceptive or vestibular signals of head tilt so that all settings were made as if the trunk and head were upright. Alternatively, patients may have used only otolith signals as the reference for upright, and these are recalibrated in ST patients with head tilt. The pathological deviation becomes accepted as upright posture, and VVs and facial orientation are estimated as if the head were upright. In either case the findings indicate abnormal processing of the perception of visual verticality in ST patients.

Adult↗

Evaluating different radiology workstation interaction techniques with radiologists and laypersons.

This paper presents a new methodology for evaluating radiology workstation interaction features, using lay subjects to perform a radiology look-alike task with artificial stimuli. We validated this methodology by evaluating two different workstation interaction techniques with two groups of subjects: laypersons and radiologists, using a set of artificial targets to simulate the reading of a diagnostic examination. Overall, the results from the two groups of subjects performing the same tasks were very similar. Both groups showed significantly faster response times using a new interaction technique, and the mouse clicks for both groups were very similar, showing that all the subjects mastered the style of interaction in a similar way. The errors made by both groups were comparable. These results show that it is possible to test new workstation interaction features using look-alike radiological tasks and inexperienced laypersons, and that the results do transfer to radiologists performing the same tasks.

Computer Systems↗

Passive moment about the hip in straight leg raising.

OBJECTIVE: The purpose of this examine is to study the load-deformation characteristics of the hip in straight leg raising. DESIGN: An experimental study in which passive moment about the hip was determined as a function of hip angle. BACKGROUND: Straight leg raising is widely employed in clinical examination, and there is little information on its mechanical characteristics. METHODS: Fourteen healthy volunteers were recruited for this study. Three trials of straight leg raise tests were performed while subjects lay supine on a plinth that was fitted with load cells. An electrogoniometer was employed to measure hip flexion during the test. Resistive moment at the hip was determined using a dynamic biomechanical model. RESULTS: The present experimental method was shown to be highly reliable. The moment-angle curves of all subjects were shown to follow an exponential function. CONCLUSION: Stiffness and strain energy of posterior hip tissues could be derived from the moment-angle curves. Evaluation of such elastic properties is clinically important as they may be altered with injuries of the tissues. RELEVANCE: Clinically, contracture of hamstring muscles and other posterior hip tissues is evaluated by measuring the available range of hip flexion in straight leg raising. However, this does not provide any information on the elastic properties of the tissues. The present study reports a reliable method of evaluating such properties.

Adult↗

The respiratory system during resuscitation: a review of the history, risk of infection during assisted ventilation, respiratory mechanics, and ventilation strategies for patients with an unprotected airway.

The fear of acquiring infectious diseases has resulted in reluctance among healthcare professionals and the lay public to perform mouth-to-mouth ventilation. However, the benefit of basic life support for a patient in cardiopulmonary or respiratory arrest greatly outweighs the risk for secondary infection in the rescuer or the patient. The distribution of ventilation volume between lungs and stomach in the unprotected airway depends on patient variables such as lower oesophageal sphincter pressure, airway resistance and respiratory system compliance, and the technique applied while performing basic or advanced airway support, such as head position, inflation flow rate and time, which determine upper airway pressure. The combination of these variables determines gas distribution between the lungs and the oesophagus and subsequently, the stomach. During bag-valve-mask ventilation of patients in respiratory or cardiac arrest with oxygen supplementation (> or = 40% oxygen), a tidal volume of 6-7 ml kg(-1) ( approximately 500 ml) given over 1-2 s until the chest rises is recommended. For bag-valve-mask ventilation with room-air, a tidal volume of 10 ml kg(-1) (700-1000 ml) in an adult given over 2 s until the chest rises clearly is recommended. During mouth-to-mouth ventilation, a breath over 2 s sufficient to make the chest rise clearly (a tidal volume of approximately 10 ml kg(-1) approximately 700-1000 ml in an adult) is recommended.

History, Ancient↗

Blood digestion in Ornithodorus moubata Murray sensu stricto Walton females (Ixodoidea: Argasidae) II. Modifications of midgut cells related to the digestive cycle and to the triggering action of mating.

The cellular organisation of midgut cells (see Grandjean, in press) depends on the digestive cycle which follows a blood meal. The phases of this cycle are characterised in O. moubata, and various "cell-types" are described, correlated and discussed. Mating triggers digestion: a) by an increased intracellular digestion (including the formation of heterophagolysosomes) during the rapid phase of digestion; b) by reactivating midgut cells in starving females, which then may perform vitellogenesis and lay few normal eggs.

Animals↗

Relation between tonic immobility and production estimated by factorial correspondence analysis in Japanese quail.

Duration of tonic immobility (TI) is a well-established criterion of fearfulness in birds, but its relation to production traits has been little studied. TI and 27 variables related to egg production and quality, feed consumption, and body condition were collected for 355 female Japanese quail. Experimental birds were the F2 generation from a reciprocal cross between a line selected for long TI and a line from a different origin and selected for early egg production. TI and several other variables had very asymetrical distributions so all variables were categorized, and the association between traits was studied by factorial correspondence analysis (FCA). Attributes of good versus poor layers were well separated by the FCA, but no association was obtained between TI and other traits on the primary axes of the FCA. Fearfulness, as measured by TI, was not related to levels of performance of egg laying quail. Secondary negative associations between TI and body temperature and between TI and residual feed consumption were obtained; however, they were marginal and need to be confirmed.

Animals↗

The effects of different beak trimming techniques on plasma corticosterone and performance criteria in Single Comb White Leghorn hens.

DeKalb XL chicks were given a beak trim at 6 d of age (6DP) with a 2.8-mm gauge and a beak trim at 11 wk (11WB) with a block cut approximately 2 mm anterior to the nasal openings. Corticosterone (CS) levels of the 6DP treatment were (P < or = 0.01) elevated above nontrimmed CS levels at 2 h posttrim; and BW and feed consumption (FC) of the 6DP were depressed until 8 wk of age. At 11 wk of age, CS of the 11WB treatment was (P < or = 0.02) elevated above controls at 1, 2, 8, and 5 wk posttrim. The 11WB treatment resulted in a decrease in FC and a reduction in BW at 12, 14, and 16 wk of age, whereas there were no differences among treatments in livability during the pullet phase. At 72 wk of age, FC of the nontrimmed controls was greater than both beak trimmed treatments, and both beak trimmed treatments had greater hen housed eggs, percentage hen day egg production, and percentage livability. Both beak trimmed treatments resulted in better egg income, feed cost per hen, and net income (NI). The 6DP and 11WB beak trim treatments resulted in an improvement of NI per hen of 1.48 dollars and 1.86 dollars, respectively. In addition, both beak trimmed treatments exhibited better feather score and Hansen's test (fearfulness). It was concluded that pullets and hens could adapt to the physiological stress of beak trimming and out perform, during a lay phase, controls whose beaks were not trimmed.

Animal Husbandry↗

Causes of disease in two commercial flocks of laying hens.

Laboratory examination of all birds that were culled or died during an eight-month period in two commerical laying flocks was performed to reveal the causes of disease and their prevalence. The average weekly total of diseased birds was greater in one flock (60-69) than the other (27-37). This resulted mainly from a high incidence in the former flock of leucoses and sarcomas, although losses due to fatty liver syndrome, prolapse and cannibalism and cage layer fatigue were also marginally greater in this flock than the second. Haemangiomas occurred more frequently in the flock with the higher disease level. A total of 273 hens of the 2,000 examined from this flock had single or multiple haemangiomas. Special features of the major causes of disease were outlined and discussed. A conclusion made from this study was that histopathological examination is necessary for accurate diagnosis of avian tumours.

Animals↗

Evidence for a rapid vasodilatory contribution to immediate hyperemia in rest-to-mild and mild-to-moderate forearm exercise transitions in humans.

Controversy exists regarding the contribution of a rapid vasodilatory mechanism(s) to immediate exercise hyperemia. Previous in vivo investigations have exclusively examined rest-to-exercise (R-E) transitions where both the muscle pump and early vasodilator mechanisms may be activated. To isolate vasodilatory onset, the present study investigated the onset of exercise hyperemia in an exercise-to-exercise (E-E) transition, where no further increase in muscle pump contribution would occur. Eleven subjects lay supine and performed a step increase from rest to 3 min of mild (10% maximal voluntary contraction), rhythmic, dynamic forearm handgrip exercise, followed by a further step to moderate exercise (20% maximal voluntary contraction) in each of arm above (condition A) or below (condition B) heart level. Beat-by-beat measures of brachial arterial blood flow (Doppler ultrasound) and blood pressure (arterial tonometry) were performed. We observed an immediate increase in forearm vascular conductance in E-E transitions, and the magnitude of this increase matched that of the R-E transitions within each of the arm positions (condition A: E-E, 52.8 +/- 10.7 vs. R-E, 60.3 +/- 11.7 ml.min(-1).100 mmHg(-1), P = 0.66; condition B: E-E, 43.2 +/- 12.8 vs. R-E, 33.9 +/- 8.2 ml.min(-1).100 mmHg(-1), P = 0.52). Furthermore, changes in forearm vascular conductance were identical between R-E and E-E transitions over the first nine contraction-relaxation cycles in condition A. The immediate and identical increase in forearm vascular conductance in R-E and E-E transitions within arm positions provides strong evidence that rapid vasodilation contributes to immediate exercise hyperemia in humans. Specific vasodilatory mechanisms responsible remain to be determined.

Adaptation, Physiological↗