Development of a sports technology quality framework.

Identifying tools and processes to effectively and efficiently evaluate technologies is an area of need for many sport stakeholders. This study aimed to develop a standardised, evidence-based framework to guide the evaluation of sports technologies. In developing the framework, a review of standards, guidelines and research into sports technology was conducted. Following this, 55 experts across the sports industry were presented with a draft framework for feedback. Following a two-round Delphi survey, the final framework consisted of 25 measurable features grouped under five quality pillars. These were 1) Quality Assurance & Measurement (Accuracy, Repeatability, Reproducibility, Specifications), 2) Established Benefit (Construct Validity, Concurrent Validity, Predictive Validity, Functionality), 3) Ethics & Security (Compliance, Privacy, Ownership, Safety, Transparency, Environmental Sustainability), 4) User Experience (Usability, Robustness, Data Representation, Customer Support & Training, Accessibility) & 5) Data Management (Data Standardisation, Interoperability, Maintainability, Scalability). The framework can be used to help design and refine sports technology in order to optimise quality and maintain industry standards, as well as guide purchasing decisions by organisations. It may also serve to create a common language for organisations, manufacturers, investors, and consumers to improve the efficiency of their decision-making relating to sports technology.

Thromboelastographic profile of goat blood after the experimental injury of the femoral artery and use of QuikClot gauze and Celox gauze dressings.

The aim of this study was to evaluate the suitability of thromboelastometry for the analysis of blood test results in goats after the use of hemostatic dressings to control massive bleeding. The study was carried out on 12 goats, 6 animals in each of two subgroups. In all experimental animals incision of the femoral artery was performed, and bleeding was controlled with QuikClot gauze in the first group and Celox gauze in the second group. Dressings were applied for 60 minutes. Blood samples for thromboelastometry were collected from the jugular vein before the incision and 60 min after the application of a dressing. Clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF) and α angle (°) were measured in three standard ROTEM assays (system with generation of reaction curve, numerical parameters and size of the blood clot): intrinsic coagulation pathway (INTEM), extrinsic coagulation pathway (EXTEM) and functional fibrinogen (FIBTEM). Complete hemostasis of the injured femoral artery was found in all goats. No significant differences between pre- and post-incision thromboelastometric parameters were found in any tests in any of the groups, which indicates that the use of dressings was not associated with blood coagulation disorders. This study is the first to describe the use of thromboelastometry in goats for the assessment of clot formation and hemostatic disorders.

Thoracic endovascular aortic repair with left subclavian artery coverage without prophylactic revascularisation-early and midterm results.

BACKGROUND: The management of the left subclavian artery when coverage is necessary during thoracic aorta endografting remains a matter of debate. MATERIALS AND METHODS: A retrospective analysis of a single-centre experience with thoracic endovascular aorta repair (TEVAR) was performed. Between April 2004 and October 2012, 125 cases of TEVAR were performed. The analysis focused on patients who required coverage of the left subclavian artery (LSA). We analysed mortality and morbidity with special attention to the rates of cerebrovascular accidents (CVAs) and spinal cord ischaemia (SCI) in the early and midterm. RESULTS: Of the 125 patients, 53 (42 %, group A) required an intentional coverage of the LSA to obtain an adequate proximal seal for the endograft; the remaining patients constituted group B. None of the patients in group A had protective LSA revascularisation prior to TEVAR. The primary technical success rate was 79.2 vs. 90.3 % (group A vs. group B, p = 0.08), and the primary clinical success rate was 77.4 vs. 82 % (group A vs. group B, p = 0.53). The 30-day mortality rate was 11.3 vs. 11.1 % (group A vs. group B, p = 0.97). The 30-day morbidity was 7.5 vs. 13.9 % (group A vs. group B, p = 0.4). CVA occurred in 1.9 % of group A patients, compared to 1.4 % of patients from group B (p = 0.82). The SCI incidence rate was 0 vs. 1.4 % (p = 0.39). The mean follow-up of group A was 24.1 months (range 2-64.6 months, SD = 19). Additionally, the 1-year estimated survival was 85.5 %, and the 3-year estimated survival was 78 %. There were no midterm CVAs; one event of SCI occurred in the seventh post-operative month in group A. CONCLUSION: Our analysis, although retrospective and based on one institution experience, shows a realistic population of TEVAR patients. We prove that TEVAR with coverage of LSA origin can be accomplished with minimal neurological morbidity in this patient population. The study shows that LSA revascularisation is not mandatory before endograft deployment, especially in emergency settings. We also prove that although zone 2 TEVAR extends the proximal landing zone, it does not prevent type IA endoleaks from appearing. A multicentre randomised control trial with higher number of patients is necessary for proper, robust conclusion to be established.

Adsorption of gas-phase elemental mercury by sulphonitrided steel sheet. Effect of hydrogen treatment.

Coal combustion, which is one of the most important energy sources of electricity generation, produces airborne pollutants: NOx, CO2, SO2, particulates and Hg°. A range of technologies is being developed to reduce the environmental impact of coal-fired power stations. No optimal technology that can be broadly applied exists as yet, but sorption of mercury is considered a promising approach. We report a novel adsorbent, which shows an extraordinary mechanical resistance and high adsorption capacity of mercury vapour. These adsorbent samples were synthesized in the gas sulphonitriding process using steel sheets. The chemisorption capacity of the sorbent materials, the process of the thermal desorption of mercury and the effect of the hydrogen activation treatment have been investigated in the work. It has been established that the capacity of mercury chemisorption increased more than twice after the heating treatment of the adsorbent in H2 atmosphere at 500 °C in comparison with the non-activated one. The mechanism of activation has been elucidated in the paper. For the purpose of comparison, activated carbon was also investigated.

Renal transplantation in dialysis patients with the history of coronary artery bypass grafting and cardiac valve replacement.

Death with a functioning kidney is the most frequent cause of graft failure. Cardiovascular disease is the most frequent cause of death after renal transplantation. Therefore, prior to grafting, it is mandatory to diagnose and treat coronary artery disease and heart valve impairment. Transplantation is the best option for renal replacement therapy as far as the quality of life and life expectancy are concerned, although patients with such comorbidities may experience a higher short-term mortality risk. The objective for this study was to analyze both short- and long-term results of patients after coronary artery bypass grafting (CABG) or cardiac valve replacement (CVR). The cardiac surgery recipient group (CSR) included 16 patients (15 men, 1 woman) aged from 44 to 73 (mean 54.9 +/- 7.8) years. CABG was performed in 13/16 patients, and CVR in 3/16. The rest of our patients were treated as a comparative noncardiac surgery recipient (non-CSR) group. It consisted of 422 patients (264 men, 158 women) aged from 14 to 68 years (mean 43.2 +/- 12.9). The comparison revealed that graft function estimated at 1 year after transplantation was not different: serum creatinine concentrations of 1.7 +/- 0.2 and 1.6 +/- 0.5 mg/dL in CSR and non-CSR, respectively. One-year patient survival in the CVR group of 93.8% was slightly worse than that in the non-CSR group (97.9%), but death-censored 1-year graft survivals were comparable in both groups (93.8% vs 92%). Urinary tract and cytomegalovirus infections were the most common complications in the CSR group. One patient lost his graft in month 3(rd) due to many serious infectious complications. One patient died at the end of 12 months as a result of a cardiovascular event (1/16). Our single-center results confirm that transplantation in patients after CABG or CVR is a safe procedure; therefore, such patients should be referred into the waiting list.

The New 3D Printed Left Atrial Appendage Closure with a Novel Holdfast Device: A Pre-Clinical Feasibility Animal Study.

INTRODUCTION: Many patients undergoing cardiac surgery have risk factors for both atrial fibrillation (AF) and stroke. The left atrial appendage (LAA) is the primary site for thrombi formation. The most severe complication of emboli derived from LAA is stroke, which is associated with a 12-month mortality rate of 38% and a 12-month recurrence rate of 17%. The most common form of treatment for atrial fibrillation and stroke prevention is the pharmacological therapy with anticoagulants. Nonetheless this form of therapy is associated with high risk of major bleeding. Therefore LAA occlusion devices should be tested for their ability to reduce future cerebral ischemic events in patients with high-risk of haemorrhage. AIM: The aim of this study was to evaluate the safety and feasibility of a novel left atrial appendage exclusion device with a minimally invasive introducer in a swine model. MATERIALS AND METHODS: A completely novel LAA device, which is composed of two tubes connected together using a specially created bail, was designed using finite element modelling (FEM) to obtain an optimal support force of 36 N at the closure line. The monolithic form of the occluder was obtained by using additive manufacturing of granular PA2200 powder with the technology of selective laser sintering (SLS). Fifteen swine were included in the feasibility tests, with 10 animals undergoing fourteen days of follow-up and 5 animals undergoing long-term observation of 3 months. For one animal, the follow-up was further prolonged to 6 months. The device was placed via minithoracotomy. After the observation period, all of the animals were euthanized, and their hearts were tested for LAA closure and local inflammatory and tissue response. RESULTS: After the defined observation period, all fifteen hearts were explanted. In all cases the full closure of the LAA was achieved. The macroscopic and microscopic evaluation of the explanted hearts showed that all devices were securely integrated in the surrounding tissues. No pericarditis or macroscopic signs of inflammation at the site of the device were found. All pigs were in good condition with normal weight gain and no other clinical symptoms. CONCLUSION: This novel 3D printed left atrial appendage closure technique with a novel holdfast device was proven to be safe and feasible in all pigs. A benign healing process without inflammation and damage to the surrounding structures or evidence of new thrombi formation was observed. Moreover, the uncomplicated survival and full LAA exclusion in all animals demonstrate the efficacy of this novel and relatively cheap device. Further clinical evaluation and implementation studies should be performed to introduce this new technology into clinical practice.

Cost-effectiveness of care for very low birth weight infants.

OBJECTIVE: Very low birth weight (VLBW)infants (those with birth weights <1500 g) account for only 1.2% of births but 46% of infant deaths. Large improvements in neonatal technology in the last 2 decades have significantly improved survival prospects for infants with low birth weights, but at a high cost. Due largely to a lack of data, the costs of medical care during the period in which infant mortality is measured (the first year of life), as well as the cost-effectiveness of that care for VLBW infants, have not been quantified. Despite this fact, public policies both toward providing insurance coverage for their care, as well as denying payment for their treatment, have either been proposed or implemented on cost-effectiveness grounds. PATIENTS: The study includes all VLBW single live births in the state of California during 1986 and 1987 that were continuously eligible (through traditional channels) for the state's Medicaid program. MAIN OUTCOME MEASURES: Treatment costs were measured for all medical care received during the first year of life, including all inpatient and outpatient care received. The cost-effectiveness of care is measured by aggregate treatment costs for all singleton VLBW liveborns divided by the number of first-year survivors. RESULTS: Average treatment costs per first-year survivor for infants <1500 g was $93 800 (in 1987 constant dollars). Treatment costs per survivor were twice as high for infants <750 g ($273 900) as for the next highest birth weight group 750 to 999 g ($138 800) which was itself almost twice as high as for the 1000 to 1249 g group ($75 100). The gradient in cost-effectiveness with birth weight then drops off to $58 000 per survivor for infants with birth weights between 1250 and 1499 g. CONCLUSION: Public policies aimed at improving birth outcomes by providing insurance coverage for pregnant women and children, such as the recent Medicaid expansions, can potentially be very cost-effective. Although maternal interventions such as prenatal care are relatively inexpensive, each normal birth that results instead in a VLBW birth saves $59 700 in first year medical expenses. However, cost savings attributable to increased birth weights depend on where in the birth weight distribution the increase occurs as well as the size of the birth weight increase. For infants with birth weights >750 g, significant gains can accrue from even a small shift in the birth weight distribution. A shift of 250 g at birth saves an average of $12 000 to $16 000 in first year medical costs and a shift of 500 g generates $28 000 in savings. However, there is a threshold effect on birth weight. For infants <750 g, increases in birth weight may increase medical expenditures. For instance, a shift in birth weight to the 750 to 999 g range increases costs by $29 000.

Stroke volume variability--cardiovascular response to orthostatic maneuver in patients with coronary artery diseases.

The dynamics of cardiovascular responses to postural stress have not been fully recognized. To determine whether coronary artery bypass grafting (CABG) has any effect on stroke volume variability (SVV), the power spectrum components of SVV were measured in 60 patients before and at 6 weeks after CABG. Stroke volume was assessed by means of the thoracic bioimpedance method. The thoracic impedance cardiogram and ECG were recorded in the supine and standing positions with controlled breathing rate (0.25 Hz) during 10-minute periods. The analysis of SVV was done by means of the autoregressive method. The total power, the power in the low-frequency band LFSV (0.05-0.15 Hz), the power in the high-frequency band HFSV (0.15-0.5 Hz), and the LFSV/HFSV ratio were analyzed. Before CABG, we did not notice any significant changes in the stroke volume spectral power indices. After CABG, all spectral indices were significantly decreased in the standing position.

Health insurance and retirement behavior: evidence from the health and retirement survey.

This paper studies the role of health insurance in the retirement decisions of older workers. As policymakers consider mechanisms for how to increase access to affordable health insurance for the near elderly, considerations of the potential labor force implications of such policies will be important to consider--potentially inducing retirements just at a time when the labor force is shrinking. Using data from the 1992 and 1996 waves of the Health and Retirement Survey, this study demonstrates that access to post-retirement health insurance has a large effect on retirement. Among older male workers, those with retiree health benefit offers are 68% more likely to retire (and those with non-employment based insurance are 44% more likely to retire) than their counterparts who would lose employment-based health insurance upon retirement. In addition, the study demonstrated that in retirement models, when retiree health benefits are controlled for, the effects of pension coverage are reduced, suggesting that these effects may have been overestimated in the prior literature.

Estimating the indirect costs of teaching.

Medicare's Prospective Payment System pays teaching hospitals using a regression coefficient in a log-log cost function. Previous literature showed that this coefficient is sensitive to the covariates included in the function, but specified teaching intensity as the logarithm of one plus the intern and resident-to-bed ratio. Provided the true relationship is log-log, adding one biases the coefficient substantially but not predicted cost. In a re-specified equation that makes this bias negligible, the coefficient is not nearly as sensitive to the inclusion of other covariates. Because further issues remain to be explored, it is premature to use our results for policy purposes.

Comparison of alternative weight recalibration methods for diagnosis-related groups.

In this article, alternative methodologies for recalibration of the diagnosis-related group (DRG) weights are examined. Based on 1984 data, cost and charge-based weights are less congruent than those calculated with 1981 data. Previous studies using 1981 data demonstrated that cost- and charge-based weights were not very different. Charge weights result in higher payments to surgical DRGs and lower payments to medical DRGs, relative to cost weights. At the provider level, charge weights result in higher payments to large urban hospitals and teaching hospitals, relative to cost weights.

How recalibration method, pricing, and coding affect DRG weights.

We compared diagnosis-related group (DRG) weights calculated using the hospital-specific relative-value (HSRV) methodology with those calculated using the standard methodology for each year from 1985 through 1989 and analyzed differences between the two methods in detail for 1989. We provide evidence suggesting that classification error and subsidies of higher weighted cases by lower weighted cases caused compression in the weights used for payment as late as the fifth year of the prospective payment system. However, later weights calculated by the standard method are not compressed because a statistical correlation between high markups and high case-mix indexes offsets the cross-subsidization. HSRV weights from the same files are compressed because this methodology is more sensitive to cross-subsidies. However, both sets of weights produce equally good estimates of hospital-level costs net of those expenses that are paid by outlier payments. The greater compression of the HSRV weights is counterbalanced by the fact that more high-weight cases qualify as outliers.

Atrial fibrillation after coronary artery bypass grafting without cardiopulmonary bypass.

OBJECTIVE: Atrial fibrillation is the most common complication after heart surgery. It rarely has a fatal outcome but causes patient instability, prolongs hospital stay, or even is the reason for perioperative infarction. Although conventional coronary artery bypass grafting (CABG) with cardiopulmonary bypass has excellent short-term and long-term results, the number of coronary operations on a beating heart without cardiopulmonary bypass is still growing. To reduce surgical trauma, off-pump coronary artery bypass grafting via sternotomy (OPCABG) or minimally invasive direct vision coronary artery bypass grafting (MIDCABG) via small thoracotomy are performed. The aim of this study was to estimate the frequency of atrial fibrillation in patients after myocardial revascularization without cardiopulmonary bypass. METHODS: A retrospective analysis of 48 patients undergoing myocardial revascularization without cardiopulmonary bypass was performed. Twenty-four patients underwent OPCABG and 24 were operated using the MIDCABG technique. The incidence of cardiac arrhythmias was analyzed since operation to the fourth postoperative day. Each patient had continuous ECG monitoring with option of arrhythmia analysis during ICU stay. After discharge from ICU 24-h ECG monitor studies were carried out. Surface 12-lead ECG was accomplished once a day, and additionally each time symptoms of cardiac arrhythmia occurred. Risk factors of atrial fibrillation were estimated. RESULTS: Atrial fibrillation occurred in 25% of patients after MIDCABG, in 29% after OPCABG, and in 18% after CABG with cardiopulmonary bypass. This difference has no statistical significance. Risk factors and incidence of postoperative complications were comparable in all groups. CONCLUSIONS: Atrial fibrillation is a common complication after procedures of myocardial revascularization, performed with or without cardiopulmonary bypass. The occurrence is not dependent on the type of operation.

IL-8 concentration in coronary sinus blood during early coronary reperfusion after ischemic arrest.

OBJECTIVE: Activation of the inflammatory response is an important factor contributing to complications of cardiopulmonary bypass. Increased level of proinflammatory cytokine - IL-8 has been reported during coronary artery bypass grafting (CABG) operations with the use of cardiopulmonary bypass. The aim of this study was to find out whether the heart is the main source of IL-8 during early coronary reperfusion. METHODS: IL-8 concentration in coronary sinus before clamping and 5, 10, and 15 min after declamping of the aorta as well as in radial artery blood before clamping and 10 min after declamping of the aorta, was assessed in 30 patients undergoing CABG surgery. RESULTS: We observed increase in IL-8 concentration in coronary sinus blood after declamping of the aorta, however no difference between coronary sinus and arterial blood concentration was noted. The median value of IL-8 concentration in coronary sinus blood was 1.85 pg/ml before ischemia and 15.4, 20.3, and 29.3 pg/ml in 5, 10 and 15 min after aortic declamping, respectively. Our additional finding was that there was a negative correlation between IL-8 level and hemoglobin saturation with oxygen in coronary sinus blood 10 min after coronary reperfusion. CONCLUSIONS: We conclude that the heart is not the main source of IL-8 in early coronary reperfusion, although coronary reperfusion induces its release.

Atrial fibrillation after coronary artery bypass grafting: does the type of procedure influence the early postoperative incidence?

OBJECTIVE: Atrial fibrillation (AF), the common postoperative complication, has been observed after coronary artery bypass grafting (CABG) in 7--40% of patients. Cardiopulmonary bypass (CPB), eliminated in off-pump operations (OPCABG) may decrease the incidence of AF, whereas the combination of CABG with heart valve replacement may result in more frequent postoperative atrial fibrillation. The aim of our study was to compare the early postoperative AF incidence rate during ICU stay in three groups of patients: after CABG, OPCABG, and CABG combined with valve replacement. MATERIAL AND METHODS: A prospective study of 906 consecutive patients was carried out between January 1999 and January 2000. Clinical profile of 906 patients, including factors having potential influence on postoperative AF did not showed any significant differences between the groups. The presence of arrhythmia history was the reason of excluding 85 patients from the statistical analysis. The observation was performed in each case during ICU-stay, using a HP system for continuous automated arrhythmia analysis. Early postoperative incidence of AF was recorded and compared between three groups of patients: 650 after conventional CABG, 118 after OPCABG, and 53 after CABG combined with valve replacement. Chi-square and a Mann--Whitney tests, Statistica 5.0 PL were used for the statistical analysis. RESULTS: Atrial fibrillation occurred during the postoperative ICU stay in 9.8% of patients after CABG, in 10.2% after OPCABG, and in 21% after CABG combined with valve replacement. There was no significant difference between CABG and OPCABG groups (P=0.965). The confidence interval of the odds ratio ranges from 0.5 to 1.85. Consequently, an increased risk would be possible for both methods. We observed a statistically significant increase of the early postoperative atrial fibrillation incidence rate in patients after CABG combined with valve replacement, when compared with both CABG + OPCABG groups (P=0.005). CONCLUSIONS: (1) Atrial fibrillation is a common postoperative complication after myocardial revascularization procedures which prolongs ICU stay. (2) The study did not show that the incidence of postoperative AF is influenced by the technique of coronary artery bypass grafting: with or without CPB. (3) The prevalence of postoperative AF increase when CABG is combined with valve replacement.

Long-term determinants of patterns of health insurance coverage in the Medicare population.

Using data from the 1990 Health Supplement to the Panel Study of Income Dynamics, we examine the determinants of patterns of insurance coverage among the elderly. Among those with supplemental insurance through an employment-based source, the primary determinant of having insurance is work history, specifically job tenure and occupation of household heads and their spouses. Among those who do not have employer-provided insurance, wealth is the most important economic factor in the purchase of private insurance. Blacks, persons with less education and women household heads are less likely to purchase supplemental insurance. We find little evidence that persons in prior poor health are more likely to purchase supplemental insurance, and the most important determinant of dental or drug coverage is having employer-based insurance. The current trend toward decreased generosity of post-retirement benefits implies that fewer older Americans will have insurance for these services.

Dental expenditures and insurance coverage among older adults.

Using data on 975 elderly persons from the 1990 Health Supplements to the Panel Study of Income Dynamics, we describe the predictors of expenditures for dental services. Forty-four percent of elderly persons reported using some dental services within a year. Thirteen percent had private dental insurance, and 8% had a separate dental policy. The average total expenditure for those who used any dental services was $378, 88% of which was paid out-of-pocket. Persons with a separate dental insurance policy, younger and better educated persons, and those with greater financial resources were more likely to use dental services.

The financial burden of prescription drug use among elderly persons.

Expenditures for prescription drugs are not covered by Medicare and are thus a potential source of large out-of-pocket expenditures for elderly persons. This study, using a new data source, the 1990 Elderly Health Supplement to the Panel Study of Income Dynamics (PSID), demonstrates that, among elderly persons, insurance coverage for drugs reduces the fraction of household income spent on prescription drugs by 50 percent. Groups most likely to benefit from insurance coverage are elderly women and those with common chronic conditions, low incomes, and rural residences.

Aortic valve replacement and perioperative management in hemodialyzed patient wth antiphospholipid syndrome.

Antiphospholipid syndrome is characterized by the presence of antiphospholipid antibodies, hypercoagulability, and prolonged phospholipid-dependent coagulation indices such as activated clotting time (ACT). Perioperative thrombotic complications are frequent among patients with antiphospholipid syndrome submitted to cardiac surgery, therefore, in these patients, heparin-protamine titration for anticoagulation monitoring is particularly recommended. We demonstrate a case of 42-year-old hemodialyzed patient with antiphospholipid syndrome, submitted to the replacement of stenotic aortic valve. In our patient celite ACT and heparin concentration during cardiopulmonary bypass did not correspond to each other. Anticoagulation based on heparin concentration assessment resulted in safe perioperative hemostatic management.

[Less invasive coronary artery bypass grafting]. / Mniej inwazyjne zabiegi przeslowania aortalno-wiencowego.

Myocardial revascularization had its beginnings in the early 1900s with extracardiac operations, such as sympathetic denervation and thyroid ablation. Since than it evolved to saphenous vein- and mammary artery-coronary artery bypass grafting (CABG) on the beating heart in the 1960s and after 1975 with the use of cardiopulmonary bypass (CPB) and cardioplegic arrest. Although excellent short-term and long-term results have been obtained with conventional CABG on cardiopulmonary bypass, there is still significant mortality and morbidity associated with the procedure, especially in the higher risk patients. To reduce surgical trauma off-pump coronary artery bypass grafting (OPCABG) and minimally invasive direct vision coronary artery bypass grafting (MIDCABG) are performed. Totally endoscopic operations are still in experimental stage. In the article optional less invasive surgical techniques are described.