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.

Long-term survival benefit of SAVR over TAVR in low-risk elective patients

Background

Aortic valve (AV) stenosis can be treated either by surgical AV replacement (SAVR) or since 2002 by transcatheter aortic valve implantation (TAVI). Due to lower invasiveness, TAVI is a preferred approach in high- and prohibitive risk surgical candidates, yet outcome data is conflicting when lower risk patients are considered and in particular at long-term.

Purpose

Our study evaluates long-term survival in elective low-risk patients after AV replacement with severe AV stenosis.

Methods

We conducted a registry data analyses of patients scheduled for elective isolated AV with AV stenosis between 2015 and 2019 and underwent TAVI or SAVR. Urgent, emergent and salvage procedures were excluded. In TAVI group only transfemoral access was considered. Propensity score matching to determine SAVR controls for TAVI group in 1:3 ratio with caliper 0.2 of standardized deviation (figure 1).

Results

Study group included 2393 elective AVR patients 1765 was in SAVR group and 628 in TAVI group. Median follow-up was 2.72 years ([IQR: 1.32–4.08], max 6.0). Propensity matching with replacement returned 329 TAVI cases and 593 SAVR controls with median age 76 (Interquartile range [IQR:71–73]) and EuroScore II 1.81 [IQR:1.36–2.53]). 30-day mortality was 11/329 (3.32%) vs 18/593 (3.03%) in the TAVI vs SAVR respectively (RR 1.10 [0.52–2.37]; p=0.801). At two years, there was no difference between SAVR and TAVI in terms of mortality (HR 1.23 [0.83–1.83] P=0.309). At 6 years, overall survival analysis favored SAVR which was associated with 30% lower mortality (HR 0.70 [0.496–0.997]; p=0.048, see figure 2).

Conclusions

TAVI as compared to SAVR is equally safe in elective low-risk patients up to 2 years post-op. After that time survival is better in surgically managed patients. Extended observations from randomized trials in low-risk patients are warranted to draw definite conclusions regarding long-term safety of TAVI in this population.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The work was supported by the research non-commercial grant from Medical University of Silesia Figure 1Figure 2

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: NO_x, 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.

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.

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.

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.

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.

Microscopic examination of bone marrow aspirate in healthy adults - comparison of two techniques of slide preparation

INTRODUCTION

According to the International Council for Standardization in Hematology (ICSH) guidelines for the standardization of bone marrow specimens and reports, smears from bone marrow aspirates for microscopic examination should be prepared using two techniques simultaneously: the wedge-spread and the crush technique. However, the outcomes of these techniques have never been compared.

METHODS

We investigated the bone marrow of 105 adult, haematologically healthy subjects, using bone marrow smears prepared via both techniques simultaneously.

RESULTS

Comparison of the two techniques revealed significant differences in terms of the composition of bone marrow cells. Only the percentages of lymphocytes, mature eosinophils and basophils did not differ significantly. The reference ranges for each technique were established.

CONCLUSIONS

The crush technique seems to be more valuable than the wedge-spread technique because of the lack of a blood dilution effect and better assessment of megakaryopoiesis. We recommend the crush technique for the evaluation of the percentage composition of bone marrow cells. In a very small number of patients with irregular cell localization in the bone marrow particles, the wedge-spread technique may be more beneficial for the assessment of total cellularity. The recommendation to routinely prepare slides using both of these techniques is fully justified.

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.

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.

Application of intraoperative thermography in coronary artery bypass grafting without extracorporeal circulation - clinical report

BACKGROUND

The development of low-invasive cardiosurgical techniques has contributed to an increase of the number of revascularization procedures performed on beating heart. The report presents the changes observed intraoperatively in thermographic images of the heart obtained during surgical revascularization performed without extracorporeal circulation.

MATERIAL AND METHODS

In two patients with coronary heart disease, subjected to coronary artery bypass grafting performed without extracorporeal circulation, the images acquired over the operation area were recorded intraoperatively using a thermovision camera (Agema Thermovision SW/TE 900 system).

RESULTS

On the basis of thermographic images, the area of lowered temperature corresponding to the region of myocardium with impaired blood flow supplied by the descending anterior coronary artery branch was determined. A rapid temperature increase to the baseline values was observed soon after removing the ligatures from the descending anterior coronary artery and left internal mammary artery used as a bypass.

CONCLUSIONS

Recording thermographic heart images allows to observe restricted areas of perfusion disturbances, which take place during procedures performed on beating heart.

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.

Collaborative quality improvement for neonatal intensive care. NIC/Q Project Investigators of the Vermont Oxford Network

OBJECTIVE

To make measurable improvements in the quality and cost of neonatal intensive care using a multidisciplinary collaborative quality improvement model.

DESIGN

Interventional study. Patient demographic and clinical information for infants with birth weight 501 to 1500 g was collected using the Vermont Oxford Network Database for January 1, 1994 to December 31, 1997.

SETTING

Ten self-selected neonatal intensive care units (NICUs) received the intervention. They formed 2 subgroups (6 NICUs working on infection, 4 NICUs working on chronic lung disease). Sixty-six other NICUs served as a contemporaneous comparison group.

PATIENTS

Infants with birth weight 501 to 1500 g born at or admitted within 28 days of birth between 1994 and 1997 to the 6 study NICUs in the infection group (n = 3063) and the 66 comparison NICUs (n = 21 509); infants with birth weight 501 to 1000 g at the 4 study NICUs in the chronic lung disease group (n = 738).

INTERVENTIONS

NICUs formed multidisciplinary teams that worked together under the direction of a trained facilitator over a 3-year period beginning in January 1995. They received instruction in quality improvement, reviewed performance data, identified common improvement goals, and implemented "potentially better practices" developed through analysis of the processes of care, literature review, and site visits.

MAIN OUTCOME MEASURES

The rates of infection after the third day of life with coagulase-negative staphylococcal or other bacterial pathogens for infants with birth weight 501 to 1500 g, and the rates of oxygen supplementation or death at 36 weeks' adjusted gestational age for infants with birth weight 501 to 1000 g.

RESULTS

Between 1994 and 1996, the rate of infection with coagulase-negative staphylococcus decreased from 22.0% to 16.6% at the 6 project NICUs in the infection group; the rate of supplemental oxygen at 36 weeks' adjusted gestational age decreased from 43.5% to 31.5% at the 4 NICUs in the chronic lung disease group. There was heterogeneity in the effects among the NICUs in both project groups. The changes observed at the project NICUs for these outcomes were significantly larger than those observed at the 66 comparison NICUs over the 4-year period from 1994 to 1997.

CONCLUSION

We conclude that multidisciplinary collaborative quality improvement has the potential to improve the outcomes of neonatal intensive care.

Administration of clemastine--H1 histamine receptor blocker in the prevention of haemodynamic disorders after protamine sulfate administration in patients subjected to coronary artery bypass grafting in extracorporeal circulation

INTRODUCTION

Adverse effects of protamine administration after CPB: fall in arterial blood pressure and pulmonary hypertension are still a source of problems. CPB and protamine administration are both accompanied by increased histamine levels in blood. The aim of this study was to examine if clemastine can accelerate the normalisation of arterial blood pressure during the protamine administration after CPB during CABG operations.

MATERIAL AND METHODS

Fifty three patients subjected to CABG operations were studied. Control group (n = 27) did not receive clemastine, Clemastine group (n = 26) received 2 mg i.v. clemastine, before CPB. After CPB were completed, patients were given protamine (heparin to protamine ratio--1:1.5) within 7 minutes, through peripheral vein. Changes in arterial blood pressure from the beginning of protamine administration to 2.5, 5, 7.5, 10, 15, and 30 minutes thereafter, as well as heart rate, CVP, doses of inotropic drugs and vasodilators were compared between the groups.

RESULTS

No difference in heart rate, CVP, doses of inotropic drugs and vasodilators between the group was noted. An increase in arterial blood pressure 5, 7.5, 10, and 15 minutes after the beginning of the protamine administration were greater in clemastine group than in control group. Groups were comparable with regard to surgical procedures and doses of anaesthetic drugs. It is now known that protamine exerts a negative effect on cardiac contractility either through a decrease in coronary perfusion pressure (vasodilatation), or through a direct toxic effect on cardiac muscle. The administration of clemastine before CPB can reduce peripheral vasodilatation and capillary leak related to histamine release during CPB. In the clemastine group, faster increase in arterial blood pressure toward a physiologic range was observed. We conclude that administration of clemastine is connected with the normalization of ABP during and after protamine reversal of heparin coagulation during CABG operations.

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.

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.

Thermographic assessment of stellate ganglion block effectiveness during cardiosurgical procedures

The study present thermographic assessment of the effectiveness of temporary stellate blockade performed during cardiosurgical procedures. The assumption behind this method was the increase in the temperature of upper extremity on the side of blockade, due to the broadening of arterial bed.

MATERIAL AND METHOD

The study was conducted on a group of 30 patients (21 men and 9 women) operated due to coronary disease involving three vessels. Mean age of the patients was 53 years. After introduction of anaesthesia blockade were performed with 2 ml 2% lignocainum and 8 ml 0.5% bupivacaine solution using peratracheal approach. Blockade effectiveness was assessed on the basis of images obtained in thermovisual camera, comparing the temperatures of upper extremity before and within 15 minutes after performing the blockade. Free blood outflow from radial artery, its diameter and length were also evaluated. The results obtained were subject to statistical analysis.

RESULTS

Twenty-three patients (76.6%) displayed the increase in the temperature of upper extremity by 1-3 degrees C. Free blood outflow from radial artery was greater in this group than in the remaining patients.

CONCLUSIONS

Thermography is a useful method for the assessment of stellate blockade effectiveness. Effective blockade results in the increased blood flow in radial artery.

[Less invasive coronary artery bypass grafting]

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.

Insurance coverage for prescription drugs: effects on use and expenditures in the Medicare population

BACKGROUND

Although most of the elderly are covered by Medicare, they potentially face large out-of-pocket costs for their health care because of excluded services. Aside from nursing home care, the exclusion of prescription drugs is one of the most significant. Several earlier policy initiatives have proposed adding prescription drug coverage to the Medicare program. To determine the effects of such an expansion, one must account for the potential increase in the demand for prescription drugs from providing insurance coverage.

METHODS

The study uses a new data source, the RAND Elderly Health Supplement to the 1990 Panel Study of Income Dynamics (PSID). The endogenity of insurance coverage is tested using instruments that exploit the longitudinal nature of the data. Equations are estimated on 910 persons (> or = 66 years) using a two-part model.

RESULTS

Insurance coverage for prescription drugs significantly increases the probability of use, but not of total expenditures, among those who use prescription drugs. However, insurance coverage significantly lowers out-of-pocket expenditures, thereby decreasing the financial burden on elderly households associated with prescription drug use. Medicaid coverage has effects that are smaller than those for private insurance, but the magnitude is less precisely estimated. These findings imply that if prescription drug coverage were added to Medicare, expected expenditures on drugs would rise by on average $83 for each elderly Medicare beneficiary (in 1990 dollars), although this increase is significant only at the 90% level. If the benefit had been included under Medicare, expected spending on prescription drugs by the elderly would have risen by approximately 20%, or $2.6 billion in 1990.

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.

Measuring the cost of neonatal and perinatal care

This article provides an overview of neonatal intensive care unit (NICU) treatment costs. It discusses data sources as well as the methods for measuring costs, contrasting the strengths and weaknesses of alternate approaches. In addition, detailed information on NICU treatment costs is presented from a nationally representative sample of 25 hospitals with NICUs. The sample consists of 3288 very low birth weight infants (</=1500 g at birth) with admission dates between January 1, 1993, and September 30, 1994. Information on median treatment cost per infant, ancillary costs, accommodation costs, length of stay, and cost per day are presented. In addition, ancillary costs are disaggregated further into those for respiratory therapy, laboratory, radiology, pharmacy, and all other ancillary services.

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.

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.

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.

Hospital and patient characteristics associated with variation in 28-day mortality rates for very low birth weight infants. Vermont Oxford Network

BACKGROUND

The outcomes for very low birth weight infants vary among neonatal intensive care units (NICUs), but the reasons for this variation are not well understood. We used the database of a large neonatology research network to determine whether either admission characteristics of the infants or specific characteristics of the units such as annual patient volume and the presence of a pediatric residency program could account for observed differences in neonatal mortality rates among units.

METHODS

We studied 7672 infants with birth weights from 501 to 1500 g treated during 1991 and 1992 at 62 NICUs participating in the Vermont Oxford Network Database.

RESULTS

Overall, 14.7% of the study infants died within 28 days of birth (interquartile range 9.9% to 18.1%). The ratio of the number of observed deaths at an NICU to the number of deaths predicted based on the characteristics of infants treated at the NICU (standardized neonatal mortality ratio, [SNMR]) varied significantly among units (range 0 to 1.69, z = 4.24). There was no association between annual patient volume and either mortality rate (r = .17) or SNMR (r = .22). Observed mortality rates (17% vs 13%) and SNMR (1.04 vs .87) were both higher at the 24 hospitals with pediatric residency training programs than at the 38 hospitals without such programs. Hospitals with residency programs had higher average annual patient volumes (104 vs 66). In an analysis simultaneously adjusting for patient characteristics, volume, and presence of a residency program, neither volume (odds ratio [OR] per 10 additional cases treated 1.01, 95% confidence interval [CI], .98 to 1.04) nor presence of a pediatric residency program (OR 1.18, 95% CI, .94 to 1.47) was significantly associated with neonatal mortality risk.

CONCLUSION

There are differences in neonatal mortality rates among NICUs that cannot be explained by differences in the measured admission characteristics of the infants, suggesting that the effectiveness of medical care varies among units. Neither the annual volume of very low birth weight infants treated in a unit nor the presence of a pediatric residency training program was independently associated with neonatal mortality rates for very low birth weight infants.

Functional associations of "trouble seeing"

The purpose of this study was to determine how vision problems affect health status. The information was collected in 1990 from 2,249 household heads and spouses over 50 years of age during an annual survey of a nationally representative sample that was adjusted for attrition and nonresponse. Vision problems were defined as "trouble seeing (even with glasses or contact lenses)." Health status was measured principally with the Medical Outcomes Study Short-Form 36. Regression analyses found a significant relationship between "trouble seeing" and each of five health-status domains. We conclude that it may not be appropriate to require specific functional limitations as a precondition for cataract surgery and that instruments for measuring functional disabilities related to vision should include more general questions.

Reproductive history, socioeconomic status, and self-reported health status of women aged 50 years or older

OBJECTIVES

This paper describes the relationship between self-reported general health status and several facets of reproductive history.

METHODS

We analyzed survey data on a national probability sample of 1341 women aged 50 and older from the Panel Study of Income Dynamics. We used multivariate regression techniques to control for differences in health indices that assessed health status and functioning.

RESULTS

Women with a history of six or more completed pregnancies were found to be disadvantaged in educational attainment, financial resources, and health status compared with women with no or fewer pregnancies. When current sociodemographic factors were controlled, six or more pregnancies were associated with worse general health and worse physical role functioning. When sociodemographic factors and number of births were controlled, among women with at least one delivery, women who had experienced an infant's death reported worse health as measured by all three indices. Women with a first delivery before the age of 18 were more likely to report a functional limitation.

CONCLUSIONS

Women with high parity status, a history of an infant's death, and an early first pregnancy may be at greater risk of poor health in later life.

Heart rate power spectral analysis in patients before and 6 weeks after coronary artery bypass grafting

Decreased cardiac vagal activity is a known risk factor in coronary artery disease. The aim of our study was to determine the effect of coronary artery bypass grafting (CABG) on heart rate variability (HRV) before and 6 weeks after CABG. The study group consisted of 34 patients (4 women, 30 men, mean age 56 +/- 9 years). ECGs were recorded in 10 minutes periods in both supine and standing position with controlled breathing rate (0.25Hz). The analysis of HRV power spectrum was done by means of fast Fourier transformation. The total spectral power (TPS), power in very low frequency band (VLF: < 0.05 Hz), low frequency band (LF:0.05-0.15Hz), high frequency band (HF:0.15-0.5Hz), LF/HF ratio and percentage fraction of total power in these frequency bands (%VLF, %LF, %HF) were analysed. Significant attenuation of all spectral components of HRV were found during orthostatic load before CABG (p < 0.05). TPS, VLF, LF, %HF decreased in standing position to about half of their level in supine position, HF decreased to as little as one fourth, while LF/HF ratio and %LF increased significantly (p < 0.05). After the CABG these changes were not significant. We have found significant increase of HF (p < 0.05) and %HF (p < 0.01) in standing position after the CABG. The results suggest that CABG causes an improvement in cardiac vagal activity especially in standing position.

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.

Sociodemographic and health factors in driving patterns after 50 years of age

Data from the 1990 Panel Study of Income Dynamics were used to predict, by means of logistic regression, the likelihood that people who had previously driven would continue to drive and to drive after dark after 50 years of age. The results support the conclusion that driving patterns appear to be explained partly by a combination of sociodemographic factors and health status. Furthermore, it is shown that those reported to drive for nondrivers appear to be the same individuals known to provide most informal support for functionally impaired elderly people.

Aneurysm of the abdominal aorta ruptured to the retroperitoneal space and inferior vena cava. Case report

Case of sixty-six year old male with abdominal aortic aneurysm rupturing into the retroperitoneal space and inferior vena cava is presented because of its rarity. Patient was operated upon with initial success but died probably due to pulmonary embolism with thrombus originating from the inferior vena cava narrowed at surgery.

Supervised six-months treatment of newly diagnosed pulmonary tuberculosis using isoniazid, rifampin, and pyrazinamide with and without streptomycin

In a previous study, we have shown that a 6-month regimen consisting of 2 months of isoniazid, rifampin, pyrazinamide, and streptomycin administered daily (2IRSZ) followed by 4 months of isoniazid and rifampin administered twice weekly (4I2R2) yielded no relapses after 30 months of follow-up. In order to assess the contribution of streptomycin to this treatment regimen, 213 patients with newly detected smear-positive pulmonary tuberculosis were randomly assigned to the following two 6-month treatment regimens: 2IRZ/4I2R2 and 2IRSZ/4I2R2. One hundred seventy-two of the 213 patients (81%) completed therapy, i.e., 116 of 135 patients (86%) treated with 2IRZ/4I2R2 and 56 of 78 patients (72%) treated with 2IRSZ/4I2R2. Adverse reactions requiring withdrawal of drugs for 7 days or longer were observed in 4.2% of patients (3.7% receiving the 2IRZ/4I2R2 regimen and 5.1% receiving the 2IRSZ/4I2R2 regimen). At the end of treatment, all patients in the 2IRZ/I2R2 series had negative smears and cultures. Two of the 116 patients (1.7%) in the 2IRZ/I2R2 series developed isoniazid resistance in the fourth month of treatment and remained sputum positive at the end of treatment. In the follow-up period, 4 patients (3.4%) treated with 2IRZ/4I2R2 relapsed and 1 (1.8%) treated with 2IRSZ/4I2R2 relapsed. The only significant difference between the 2 regimens was the higher dropout rate among those assigned to the 2IRSZ/4I2R2 regimen.