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Alarm management is a key component of the successful operation of a prognostic or health-monitoring technology. Although alarms can alert the operator to critical information, false alarms and alarm flooding can cause major difficulties for successfully diagnosing and acting upon infrastructure faults. Human factors approaches seek to design more-effective alarm systems through a deep understanding of the contextual factors that influence alarm response, including strategies and heuristics used by operators. This paper presents an extensive analysis of alarm-handling activity in the setting of an Electrical Control Room on the rail network. The analysis is based on contextual observation, and the application of a time-stamped observation checklist. Functions, performance requirements, and general operating conditions that influence alarm handling are presented, delineating the typical operational constraints that need to be considered in the design and deployment of asset-based alarm systems. The analysis of specific alarm-handling incidents reveals the use of specific strategies that may bias operator performance. Implications for the design of health-monitoring systems are discussed.

Discussion of the dispersal of Catholic literature in post-Reformation England tends to focus on the tenacity of recusants and 'church papists' in perpetuating allegiance to Rome. Relatively little attention has been paid to the extent to which Catholic texts, either in their original form or modified for a Protestant readership, formed a part of the mainstream culture of the reformed Church. This paper attempts to demonstrate the significance of Catholic literattire in the Protestant context by showing the range of Protestant adaptations, the extent of Protestant readership and the influences of Catholic literature on Protestant writers. [ABSTRACT FROM AUTHOR]

Stroke is the third leading cause of death in the United States, Canada, Europe, and Japan. According to the American Heart Association and the American Stroke Association, there are now 750,000 new strokes that occur each year, resulting in 200,000 deaths, or 1 of every 16 deaths, per year in the United States alone. Endovascular therapy for patients with acute ischemic stroke is an area of intense investigation. The American Stroke Association has given a qualified endorsement of intra-arterial thrombolysis in selected patients. Intra-arterial thrombolysis has been studied in 2 randomized trials and numerous case series. Although 2 devices have been granted FDA phase 3 approval with an indication for mechanical stroke thrombectomy, none of these thrombectomy devices has demonstrated efficacy for the improvement of patient outcomes. The purpose of the present document is to define what constitutes adequate training to perform neuroendovascular procedures in patients with acute ischemic stroke and what performance standards should be adopted to assess outcomes. These guidelines have been written and approved by multiple neuroscience societies that historically have been directly involved in the medical, surgical and endovascular care of patients with acute stroke. These organizations include the Neurovascular Coalition and its participating societies, including the Society of NeuroInterventional Surgery (SNIS), American Academy of Neurology (AAN), American Association of Neurological SurgeonsCerebrovascular Section (AANSCNS), and Society of Vascular & Interventional Neurology (SVIN).

Nineteen Australian safety investigation reports and 13 UK safety reports were reviewed and a human error identification technique (the Technique for the Retrospective and Predictive Analysis of Cognitive Errors: TRACEr-rail version) adopted as a means of identifying and classifying errors associated with rail incidents and accidents. In the Australian sample, it was revealed that most driver errors occurred when drivers were driving or stopping their train and that these errors consistently resulted in two consequences: speeding and signals passed at danger (SPADs). In the UK, errors occurred while drivers were performing a whole range of tasks, including driving, stopping, train assembly, and failed train operations. In Australia, most ‘train driving errors’ were ‘violations’ while most ‘train stopping errors’ were errors of ‘perception’. In the UK, a more varied range of errors was observed. Overall, the TRACEr-rail framework proved useful in categorizing driver errors from existing investigation reports and in highlighting recurring errors associated with incidents and accidents. However, the tool appeared to neglect some organizational factors contributing to driver error, and, preliminary inter-rater reliability testing revealed that some category descriptions may require further refinement. Future work will aim to develop a more Australian-friendly and reliable version of TRACEr for use in Australian rail.

Since the 1940s, researchers have grappled with the notion of a mental model. The concept is eminently reasonable and somewhat seductive, but presents us with a number of difficulties regarding its incompleteness, multiplicity, and inconsistency. Not the least of these difficulties is the problem of “capturing” (measuring) mental models, and still more difficult, capturing a team mental model, an extension of the earlier term. Once captured, finding an appropriate analytic procedure to analyze team mental models has challenged researchers for a long time. Nonetheless, the literature suggests that the construct is well worth the trouble, with many applied benefits especially to industry. In the present work we set out to (a) review the notion of team mental models (TMM); (b) identify the key concepts and thinking behind their development; (c) demonstrate how they support teamworking performance; and (d) outline a three‐phase model of TMM development. Details on TMM measurement are given, before concluding with a discussion of the difficulties facing researchers who wish to study and utilize the notion, and some of the pressing research issues that need investigation. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 331–352, 2004.

This paper presents results of the longitudinal usability and network trials that took place throughout the COVEN (COllaborative Virtual ENvironments) Project. To address the lack of understanding about usability design and evaluation for collaborative virtual environments (CVEs), a deductive analysis was used to systematically identify areas of inquiry. We present a summary of the analysis and the resulting framework through which various complementary methods were utilized during our studies. The objective of these studies was to gain a better understanding about design, usability, and utility for CVEs in a multidisciplinary setting.

Synthetic routes to porous ethylphosphonic acid-modified silicas with high T/Q ratios are described. The resulting materials were characterised using 29Si, 31P and 13C solid state NMR, nitrogen sorption porosimetry and elemental analysis. In addition, conditions for post-modification using [VO(SO₄)·5H₂O] are described; the vanadyl derivatives were characterised by porosimetry, elemental analysis, EPR and UV-Vis spectroscopy. One of these vanadyl derivatives is a useful catalyst for the oxidation of cis-cyclooctene using aqueous hydrogen peroxide as the oxidant.

This study investigated pilots' taxi performance, situation awareness and workload while taxiing with three different head-up display (HUD) symbology formats: Command-guidance, Situation-guidance and Hybrid. Command-guidance symbology provided the pilot with required control inputs to maintain centerline position; Situation-guidance symbology provided conformal, scene-linked navigation information; while the Hybrid symbology combined elements of both symbologies. Taxi performance was assessed with average taxi speed and root mean square error (RMSE) from the centerline. Situation awareness and workload were assessed using a 3- Dimension SART and a 7-point scale, respectively. Taxi speeds were highest and RMSE from centerline lowest with Situation-guidance and Hybrid symbologies. Situation awareness was highest and workload lowest with Situation-guidance and Hybrid symbologies. These results are thought to be due to cognitive tunneling induced by the Command-guidance symbology. Situation-guidance (and Hybrid) HUD symbologies provided a common reference with the environment, which may have supported better distribution of attention.

During the past decade teamwork in manufacturing, as in other sectors, has become the organisational form of choice. In contrast to earlier manifestations such as autonomous workgroups some 30 years earlier, this appears to have been largely for business and production reasons rather than being directly aimed at improving the quality of work life. Taken from part of a larger study of teamworking in several different manufacturing companies this paper draws upon a retrospective analysis of cases of self-managed team implementation in UK manufacturing. Examples of good and bad practice and consequent guidance have been identified where the weight of evidence gives confidence in their general applicability. A basis for benchmarking is provided, related to preparation, implementation and maintenance of self-managed teams in manufacturing. Key gaps identified are for tools to assist in early functional analysis, leadership decisions and boundary setting, and appropriate team performance measurement and reward systems.

Since the early 1990s a concept known as Design for Manufacturability (DFM) has developed. In the past much of the ergonomics involvement in DFM has considered the workstations and methods of human assembly operators. The increase in health and safety regulations and the number of employee compensation claims against companies for work related musculoskeletal disorders is providing the impetus for the consideration of Ergonomics for Assembly (EA) by design engineers. This project was undertaken within the context of an automotive manufacturing company. A programme for EA training for product design engineers was developed and a system proposed to support its incorporation in future design work.

This symposium is concerned to assess the current status and value of the mental model notion in human factors/ergonomics. These themes will be critically assessed in this paper, in particular questioning whether the notion is accounted for by other ideas and theories.

New demands on modern manufacturing systems have emphasised the need for higher levels of overall system reliability. The main focus of this paper is that of the reliability of manufacturing personnel and the way in which this interrelates with overall system performance. A framework - Human Error and Disturbance Occurrence in Manufacturing Systems (HEDOMS) is proposed, which integrates human reliability with overall system performance, relating human error with disturbance occurrence and handling. The HEDOMS framework has been extended into a toolkit to enable the identification of potential for human error and disturbance occurrence in manufacturing systems, as well as the definition of suitable error reduction measures.

This paper discusses one of the tools developed as part of a Railway Ergonomics Control Assessment Package (RECAP) which will be used to benchmark current human factors operations and assess the impact of new centralised control rooms on the performance and safety of the railway network. The questionnaire included sections covering areas such as workplace design, work environmental conditions, work attitude, occupational stress and teamwork. Results from initial analysis indicated that a number of workplace factors, such as workplace design, job content and teamwork, had an impact on employee well-being, including general health and job satisfaction. A number of issues associated with questionnaire design and administration were also highlighted.

A sense of presence is one of the critical components required by any effective virtual environment (VE). In contrast, side effects such as sickness may be produced in some virtual environments, detracting from the enjoyment or usefulness of the VE and from subsequent performance of the participant. Both presence and sickness in virtual environments are multifactorial phenomena not easily amenable to understanding or measurement. The first experiment reported here compares use of direct performance measures and rating scales to assess presence, whilst varying the VE display medium (head mounted and desktop displays) and whether or not sound was used in the VE. The second experiment addresses associations between presence, sickness and enjoyment of virtual environment participation. There was enough comparability between a reflex response within the VE and the rating scales to justify future exploration of the former measure of presence. A number of explanations are given for the partial association found between presence and sickness.

Demands on modern manufacturing systems include those for increased flexibility, higher quality standards, and higher innovative capacities; these demands emphasize the need for high levels of overall system reliability. This article focuses on the reliability of all human elements of a manufacturing system and the way these interrelate with overall system performance. A contrast is made with how human reliability has been approached typically in high-risk industries. The concept of “disturbance” is used for assessment of the influence of human reliability on manufacturing system performance. An analytical framework has been proposed, currently under development, which is aimed at assessing the potential for human error and disturbance occurrence in manufacturing systems, and which accounts for active and latent failures and direct and root causes. © 1999 John Wiley & Sons, Inc.

Quantification of sucrose, glucose and fructose is essential for developing a physiological understanding of growth and development of plant species. This is usually achieved by either HPLC or enzymatic assays for specific sugars. The need for reliable and cost-effective assays of large numbers of samples led us to compare microtitre plate-adapted enzymatic assays for sucrose, glucose and fructose with current HPLC protocols. The enzymatic assay techniques were modified without loss of precision or accuracy when compared to the original protocols. Application of HPLC and the modified enzymatic assay to a range of sugarcane stem extracts found no difference in assay sensitivity. The enzymatic assay had considerable advantages in terms of sample throughput and cost-effectiveness. © 1999 Society of Chemical Industry

An experimental program of research was carried out to assess the potential health and safety effects of participating in virtual environments (VEs) via head-mounted displays (HMDs). This paper presents the results obtained from nine experiments examining the effects experienced during and after participation in a variety of VR systems, VE designs, and task requirements, for a total participant sample of 148 individuals. A combination of methods including self-report scales, performance measures, physiological indicators, observation, interview, and user attitude/opinion questionnaires were used to measure simulator (VE) sickness, postural instability, psychomotor control, perceptual judgment, concentration, stress, and ergonomics effects. Greatest effects across the different systems, VEs, and exposure times were found for sickness symptoms and physiological measures, with some concern over postural instability and physical ergonomics, also. Although many of the effects were relatively minor and short lived, they were serious for five percent of participants and irritating for a considerable percentage more. The aetiology of the effects is sufficiently different to that for simulators or transport systems to justify us using a new term, virtual reality-induced symptoms and effects(VRISE). Implications are drawn for VR system design, VE specification, and the ways in which industrial use of VR/VE should be planned and supported.

Demands on modern manufacturing systems include those for increased flexibility, higher quality standards, and higher innovative capacities; these demands emphasize the need for high levels of overall system reliability. This article focuses on the reliability of all human elements of a manufacturing system and the way these interrelate with overall system performance. A contrast is made with how human reliability has been approached typically in high‐risk industries. The concept of “disturbance” is used for assessment of the influence of human reliability on manufacturing system performance. An analytical framework has been proposed, currently under development, which is aimed at assessing the potential for human error and disturbance occurrence in manufacturing systems, and which accounts for active and latent failures and direct and root causes. © 1999 John Wiley & Sons, Inc.

Background.The criteria for cardiac transplantation recipient selection, including the appropriate recipient upper age limit, continue to expand with an increasing number of recipients greater than 60 years of age. While others have reported their transplant experience in older recipients in terms of quality of life assessment, we have examined the role of exercise cardiopulmonary testing post-transplantation in older cardiac transplant recipients.

OBJECTIVES

OBJECTIVES

Multiple M-mode echocardiographic indices of left ventricular function are currently in use, but their reliability is disputed. Therefore, we correlated echo ejection fraction (EF) using quadratic (Q) and cubic (C) formulae, percentage of minor axis shortening (%S), mean velocity of circumferential fiber shortening (mVCF), and peak VCF with angiographic EF in 37 subjects, including 10 normal subjects. None had echocardiographic segmentai wall motion abnormalities. Significant linear correlations were found between angiographic EF and EFC(r= 0.78), %S (r= 0.77), EFQ(r= 0.68), peak VCF (r= 0.68), and mVCF (r= 0.58). However, for all indices, the scatter was too great to permit reliable quantitative estimations of angiographic EF based on echo date. Peak VCF was qualitatively the most reliable predictor of ventricular function, being ≥2.00 circumference per second in 23 of 25 patients with angio EF ≥55 percent and <2.00 circumferences per second in 11 of 12 with EF <55 (sensitivity [sens] 92 percent, specificity [spec] 92 percent). Mean VCF (sens 83 percent, spec 80 percent), %S (sens 50 percent, spec 96 percent), EFC(sens 58 percent, spec 96 percent), and EFQ(sens 58 percent, spec 92 percent) were less satisfactory. We conclude that echo indices are reliable only as qualitative parameters of ventricular function. Peak VCF appears to be the most sensitive and specific qualitative index now available.

To determine if patients with rest angina have more severe regional ischemia than patients with exertional angina, we compared the severity of left coronary artery (LCA) stenosis in 29 patients with transient anterior ischemic ST-T changes at rest, and 30 patients with anterior ST changes only during exertion. The percentage diameter stenosis was measured with Vernier calipers as (2 × lesion diameter × 100 percent)/(pre-stenotic + poststenotic diameter). There was no difference between the two groups in the mean diameter stenosis of unoccluded LCA vessels either when all vessels were compared (rest: 69 ± 12 percent; exertional: 70 ± 13 percent [p=NSD or when only the maximal stenosis in each patient was compared (rest: 74 ± 10 percent; exertional: 75 ± 12 percent [p=NS]). Total occlusion of at least one major vessel of the LCA also occurred with similar frequency in patients with rest (6/29) and exertional (12/30) angina (p=NS). However, collateral development distal to 76-100 percent LCA lesions was significantly less frequent in rest angina (4/21 vessels [19 percent]) than in exertional angina (21/30 vessels [70 percent]), (p < .03). We conclude that patients with rest angina do not have more severe coronary stenoses than patients with exertional angina, but frequently may have more severe regional ischemia due to reduced collaterization of jeopardized myocardium.

Objectives. The purpose of this study was to determine how often peak exercise oxygen consumption (Vo2) misclassifies the severity of cardiac dysfunction in potential heart transplant candidates.

Lang, Chim C., Don B. Chomsky, Javed Butler, Shiv Kapoor, and John R. Wilson. Prostaglandin production contributes to exercise-induced vasodilation in heart failure. J. Appl. Physiol.83(6): 1933–1940, 1997.—Endothelial release of prostaglandins may contribute to exercise-induced skeletal muscle arteriolar vasodilation in patients with heart failure. To test this hypothesis, we examined the effect of indomethacin on leg circulation and metabolism in eight chronic heart failure patients, aged 55 ± 4 yr. Central hemodynamics and leg blood flow, determined by thermodilution, and leg metabolic parameters were measured during maximum treadmill exercise before and 2 h after oral administration of indomethacin (75 mg). Leg release of 6-ketoprostaglandin F1αwas also measured. During control exercise, leg blood flow increased from 0.34 ± 0.03 to 1.99 ± 0.19 l/min (P< 0.001), leg O2consumption from 13.6 ± 1.8 to 164.5 ± 16.2 ml/min (P< 0.001), and leg prostanoid release from 54.1 ± 8.5 to 267.4 ± 35.8 pg/min (P< 0.001). Indomethacin suppressed release of prostaglandin F1α(P< 0.001) throughout exercise and decreased leg blood flow during exercise (P< 0.05). This was associated with a corresponding decrease in leg O2consumption (P< 0.05) and a higher level of femoral venous lactate at peak exercise (P< 0.01). These data suggest that release of vasodilatory prostaglandins contributes to skeletal muscle arteriolar vasodilation in patients with heart failure.

Exertional dyspnea in patients with heart failure may be due, in part, to respiratory muscle underperfusion. Near-infrared spectroscopy is a new technique that permits noninvasive assessment of skeletal muscle oxygenation by monitoring changes in nearinfrared light absorption. With use of near-infrared spectroscopy, serratus anterior muscle oxygenation during maximal bicycle exercise was compared in 10 patients with heart failure (ejection fraction 16 ± 5%) and 7 age-matched normal subjects. Oxygen consumption (VO2), minute ventilation (VE) and arterial saturation were also measured. Changes in difference in absorption between 760 and 800 nm, expressed in arbitrary units, were used to detect muscle deoxygenation.

Exertional intolerance is a major clinical problem in ambulatory patients with chronic heart failure and is associated with both muscle fatigue and dyspnea. The increased muscle fatigability is most likely caused by a combination of muscle underperfusion and muscle deconditioning; patients frequently exhibit skeletal muscle atrophy, altered muscle metabolism and reduced mitochondrialbased enzyme levels, consistent with deconditioning. The muscle underperfusion is largely due to impaired arteriolar vasodilation within exercising muscle. Exertional dyspnea appears to be due to increased respiratory muscle work mediated by excessive ventilation and decreased lung compliance. Both excessive carbon dioxide production, secondary to increased muscle lactate release, and increased lung dead space contribute to the excessive ventilation. Decreased lung compliance is caused by chronic pulmonary congestion and fibrosis. Optimal management of exercise intolerance in patients with heart failure requires an understanding of the role of these multiple potential contributors to exertional fatigue and dyspnea.

The maximal aerobic exercise capacity of patients with chronic heart failure is frequently decreased because of inadequate blood flow to working skeletal muscle. To investigate whether this reduced flow is in part due to interference by angiotensin II with arteriolar dilation in working muscle, the effect of the angiotensin-converting enzyme inhibitor captopril on leg blood flow, leg vascular resistance, leg oxygen consumption (V˙O2) and leg lactate release during maximal upright bicycle exercise was examined in 12 patients with heart failure (maximal V˙O210.7 ± 3.1 ml/min per kg). Captopril decreased leg resistance at rest (258 ± 115 to 173 ± 67 U, p < 0.01) and maximal exercise (68 ± 69 to 45 ± 29 U, p < 0.01) associated with proportionately similar decreases in systemic vascular resistance. However, maximal exercise duration and maximal V˙O2were unchanged and, at identical peak exercise work times, there was no improvement in leg blood flow (2.0 ± 0.9 to 2.0 ± 1.1 liters/min, p = NS), leg V˙O2(261 ± 104 to 281 ± 157 ml/min, p = NS) or leg lactate release (269 ± 149 to 227 ± 151 mg/min, p = NS). These data suggest that, during exercise in patients with heart failure, angiotensin II does not interfere with blood flow to working skeletal muscle.

During the past 2 years, the way in which industry views virtual reality (VR) has changed. Previously, only a few large companies were assessing virtual environments either as “internal marketing exercises” or through demonstration worlds built for them by outside consultants or universities; most other industrialists may have seen VR as only having entertainment applications. Now there is some evidence that parts of industry, and manufacturing industry in particular, see VR as an increasingly affordable technology with potentially wide-ranging applications. This paper briefly describes a recent U.K. research program MOVE (Manufacturing Operations in Virtual Environments) consisting of an industrial VR user survey and demonstration applications built to allow potential users to make informed assessments of virtual environments. Two particular applications—training for maintenance and rapid prototyping for product design—are described in greater detail as examples of industrially relevant environments, before an assessment is provided of potential VR application in manufacturing.

Investigations of the potential impact of virtual environments on user health and safety require a methodological framework to identify both the effects of VE participation and the role of influential factors in causing those effects. This first in a series of 12 experiments was designed to evaluate methods, but also provided preliminary data regarding psychological and physiological effects. This discussion centers upon the value of self-reports and performance measures and the general methodological problems of evaluating participation in virtual environments.

The majority of British households own a stepladder and around 14,000 people are injured seriously enough to visit hospital Accident and Emergency departments each year while using them in the home, one of the highest rates of injuries associated with a consumer product. The aim of this study was to look at the causes of accidents with stepladders and to identify routes for improvement in their safety. The investigation involved surveys of accidents, and of the stepladder market, and experimental work looking at how stepladders are used; the paper also describes the ergonomics methods used in the investigation. Observations of 'natural' use of stepladders demonstrated that few people follow the rules of safe stepladder use, with which nearly all step-ladders in the UK are now labelled. Of the 40 subjects observed, no one read the instructions on the stepladder before using it, no one was able to assemble a combination stepladder correctly, nearly all subjects used the stepladder sideways to the task (which is considered mis-use) and most subjects over-reached. As a result of the study a nationwide publicity campaign was launched in the UK to try to raise consumer awareness of safe stepladder use and a review of both British and European standards has been undertaken.

Drowning is the third commonest cause of accidental death of children in the UK and many children drown in domestic swimming pools. Concern has been raised about the design and safety of the covers used on domestic swimming pools since the majority of drowning and near-drowning incidents occur in pools with covers on. Swimming pool covers are a diverse range of products and fulfil a number of functions. This diversity in their design and the associated hazards necessitated a multidisciplinary approach to their evaluation. A study of the epidemiology of drownings was carried out in order to specify the risks of swimming pool covers, together with a study of the market and a survey of pool owners and their attitudes to safety. The risks of swimming pool covers were then evaluated by engineering, materials and ergonomics testing which included simulation of both the user and the products. This study is an example of the need for a mix of test methods and types of simulations in order to provide an overall statement of the safety of some consumer products. Results showed that the floating, heat retaining covers used on the majority of UK domestic pools possibly add to the intrinsic risks of a swimming pool. Winter debris covers, although appearing to seal the pool and considered by the majority of owners to make pools safer, were shown to allow children relatively easy access under the cover.

Exertional fatigue is a major limiting symptom in patients with heart failure. Nevertheless, the mechanism responsible for this fatigue remains unclear. Reduced skeletal muscle blood flow, altered muscle oxidative enzymes, decreased muscle mass and altered muscle contractility have all been implicated but the precise contribution of these factors remains to be determined. Clinically, the severity of muscle fatigue is usually determined from the patient history. This approach is unreliable since symptoms reported during normal daily activities correlate poorly with objective measures of exercise performance. The degree of perceived fatigue noted during formal exercise testing also correlates poorly with objective measures of muscle behavior, such as blood lactate levels. Cardiopulmonary exercise testing can be used to identify the onset of lactate relase, or the anaerobic threshold, and therefore provides more objective information about muscle behavior. However, an increase in blood lactate does not necessarily indicate muscle fatigue. Surface recordings of muscle electromyograms during exercise permits detection of increasing EMG signal, an indicator of fatigue. This technique is potentially valuable but is technically challenging. Finally, muscle fatigue can be assessed by monitoring developed tension during repetitive contractions of the quadriceps muscle. This index of muscle fatigability correlates relatively closely with maximal exercise performance and provides the best index of fatigue currently available. However, further studies are needed to document the clinical utility of this methodology.

The reduced maximal exercise capacity of patients with heart failure has been attributed to skeletal muscle underperfusion with resultant intramuscular lactic acidosis and muscular fatigue. To investigate this hypothesis, the effect of dichloroacetate, a drug that decreases lactate formation by increasing pyruvate oxidation, on the maximal exercise performance of 18 patients with heart failure and reduced ejection fraction (25 ± 9%) was examined. Exercise tests after parenteral dextrose (control) and dichloroacetate were performed 1 week apart. The sequence of interventions was randomized in a double-blind manner.

Intravenous immunoglobulin (IVIg) is a useful tool in the treatment of a variety of neuromuscular disorders. Though IVIg therapy is generally safe, hemolytic anemia is a potentially serious complication that is often overlooked, and is currently not listed in product inserts. We analyzed 45 patients who received IVIg therapy, including 38 consecutive patients who received IVIg over a 13‐month period. On 42 patients, direct antiglobulin testing was performed, searching for antibodies to the patients' own blood type. Of these 42 patients, 12 developed passive sensitization with antibodies to their own blood group antigens after receiving IVIg. Of these 12 patients, 11 patients developed hemolysis severe enough to lower the hemoglobin level by at least 1 g/dL. Of these patients, 3 required blood transfusion, and 1 had IVIg therapy truncated because of the hemolysis. Antibodies to blood group antigens are found in all commercial preparations of IVIg. Though most patients do not have clinically significant hemolysis, clinicians should be aware of this potentially serious complication. Careful monitoring of hemoglobin levels during IVIg therapy is recommended. © 1997 John Wiley & Sons, Inc. Muscle Nerve20:1142–1145, 1997

Intravenous immunoglobulin (IVIg) is a useful tool in the treatment of a variety of neuromuscular disorders. Though IVIg therapy is generally safe, hemolytic anemia is a potentially serious complication that is often overlooked, and is currently not listed in product inserts. We analyzed 45 patients who received IVIg therapy, including 38 consecutive patients who received IVIg over a 13-month period. On 42 patients, direct antiglobulin testing was performed, searching for antibodies to the patients' own blood type. Of these 42 patients, 12 developed passive sensitization with antibodies to their own blood group antigens after receiving IVIg. Of these 12 patients, 11 patients developed hemolysis severe enough to lower the hemoglobin level by at least 1 g/dL. Of these patients, 3 required blood transfusion, and 1 had IVIg therapy truncated because of the hemolysis. Antibodies to blood group antigens are found in all commercial preparations of IVIg. Though most patients do not have clinically significant hemolysis, clinicians should be aware of this potentially serious complication. Careful monitoring of hemoglobin levels during IVIg therapy is recommended. © 1997 John Wiley & Sons, Inc. Muscle Nerve 20:1142–1145, 1997

Lang, Chim C., Don B. Chomsky, Glenn Rayos, T. K. Yeoh, and John R. Wilson. Skeletal muscle mass and exercise performance in stable ambulatory patients with heart failure. J. Appl. Physiol.82(1): 257–261, 1997.—The purpose of this study was to determine whether skeletal muscle atrophy limits the maximal exercise capacity of stable ambulatory patients with heart failure. Body composition and maximal exercise capacity were measured in 100 stable ambulatory patients with heart failure. Body composition was assessed by using dual-energy X-ray absorption. Peak exercise oxygen consumption (V˙o2 peak) and the anaerobic threshold were measured by using a Naughton treadmill protocol and a Medical Graphics CardioO2System.V˙o2 peakaveraged 13.4 ± 3.3 ml ⋅ min−1⋅ kg−1or 43 ± 12% of normal. Lean body mass averaged 52.9 ± 10.5 kg and leg lean mass 16.5 ± 3.6 kg. Leg lean mass correlated linearly with V˙o2 peak(r= 0.68,P< 0.01), suggesting that exercise performance is influenced by skeletal muscle mass. However, lean body mass was comparable to levels noted in 1,584 normal control subjects, suggesting no decrease in muscle mass. Leg muscle mass was comparable to levels noted in 34 normal control subjects, further supporting this conclusion. These findings suggest that exercise intolerance in stable ambulatory patients with heart failure is not due to skeletal muscle atrophy.

Blood flow to working skeletal muscle is frequently reduced in patients with heart failure or peripheral vascular disease. To determine if phosphorus nuclear magnetic resonance (NMR) can noninvasively detect such muscle underperfusion, gated phosphorus-31 NMR spectroscopy was used to compare muscle inorganic phosphate, phosphocreatine and pH during mild wrist Rexion exercise at 0.2, 0.4 and 0.6 W in eight normal men, before and after reduction of forearm blood flow. Forearm Row was reduced by cuff inRation to a pressure determined by Doppler ultrasound to bring Dow to 40 to 60% of control. Attention was focused on the inorganic phosphate to phosphocreatine (Pi/PCr) ratio and pH, two variables potentially sensitive to muscle oxygen delivery.

The ability of the vectorcardiogram to detect mild circulatory abnormalities in patients with chronic obstructive pulmonary disease (COPD) is unclear. Therefore, vectorcardiographic changes were correlated with hemodynamic measurements made at rest and during supine exercise in 32 patients with COPD and no clinical or electrocardiographic evidence of right ventricular hypertrophy. Twelve patients had normal hemodynamic data (group 1), nine had abnormal hemodynamic data only during exercise (group 2), and 11 had abnormal hemodynamic data at rest and during exercise (group 3). The extent of rightward terminal QRS forces noted on the vectorcardiogram was significantly less in group 1 (5.5 ± 8.7 percent) than in either group 2 (19.0 ± 10.7 percent) or group 3 (17.8 ± 14.8 percent). Sixty-five percent (13) of the 20 patients with hemodynamic abnormalities had rightward terminal QRS forces of 15 percent or more, whereas only 8 percent (one) of the 12 patients with normal hemodynamic data had such forces of 15 percent or more. The mean of the rightward terminal QRS forces in 27 age-matched normal subjects was 5.0 ± 5.4 percent, and only one subject had forces of 15 percent or more. We conclude that hemodynamic abnormalities are frequent in patients with COPD and no clinical evidence of right ventricular hypertrophy and that the vectorcardiogram provides an indirect method of detecting these abnormalities.

It is argued that the requirement on ergonomists to develop ergonomics management programmes within industrial companies is as great as those to provide basic human data or to contribute to system analysis, design, and evaluation. Given current concerns with human reliability, work performance quality and flexibility, and health and safety, the only rational and effective way to make interventions is as part of a widespread in-house programme involving organizational and individual participation. A method of developing ergonomics is described, whereby ergonomics is first given a foundation, then spread throughout the organization and then embedded so that it is seen as a normal part of company activities across all its operations. Case studies are used to illustrate all three stages of this 'devolving ergonomics' programme.