bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular advances in cardiac and cardiovascular disease
Authors: Basile-Borgia Annette , Abel John H , Mahloogi Haleh 
Published: January 2013

Recent advances in the field of molecular biology have led to a better understanding of the pathological mechanisms of cardiovascular disease. The impact of these findings will shape the future of treatment modalities for cardiovascular disorders. Postulated targets and biological rationale of new techniques are being developed in a race towards molecular therapies for vascular diseases. Whether it is modulation of transmembrane cell receptors or phenotypic changes via vectors that mediate gene transfer, there is no doubt that molecular strategies will be an integral part of the future. Here we examine past and recent perspectives, describe directions and challenges in cardiac and cardiovascular areas of research, and discuss relevance to the field of cardiovascular perfusion.
Customized perfusion circuit for the tiny ascending aorta
Authors: Mueller Maryann W , Fraser Charles D 
Published: January 2013

Cannulating a pediatric patient with an interrupted aortic arch presents many challenges. Two cannulas are necessary to allow for proper blood flow to the head and to the extremities. This case was made more difficult by the weight of the child and the small size of the ascending aorta. The available pediatric cannulas were too large. The perfusionist adapted two 14-gauge intravenous (i.v.) catheters as arterial cannulas which were incorporated into the 1/4-inch arterial line. The 14-gauge i.v. catheters worked successfully. While on cardiopulmonary bypass, the patient was both metabolically and hemodynamically stable. The patient survived the procedure and was eventually discharged from hospital.
Assessing heparin neutralization following cardiac surgery: sensitivity of thrombin time-based assays versus protamine titration methods
Authors: LaDuca Frank M , Zucker Marcia L , Walker Charles E 
Published: January 2013

Adequate assessment of heparin neutralization following cardiac surgery is critical in reducing the patient’s exposure to protamine. Both excessive protamine and residual heparin have been associated with postoperative bleeding and poor patient recovery. The activated clotting time (ACT) is the preferred intraoperative heparin monitor, while both protamine titration (i.e. a protamine-containing ACT) and thrombin time methods have been used to detect circulating residual heparin after protamine administration. Following initial protamine dosing using the protamine response test (PRT), postoperative monitoring was employed in the operating room prior to transport of the patient to intensive care. Two point-of-care assays, the thrombin time (TT) and the protamine dose assay (PDA), were evaluated to determine their relative heparin sensitivity and their usefulness to quantitate protamine dose. The PDA, which is based on the ACT, was shown in laboratory and clinical studies to detect residual heparin above 0.25 units/ml and to quantify additional minidoses of protamine (as low as 25 mg) required to obtain complete heparin neutralization. Differential evaluation of the TT and heparin neutralized thrombin time (HNTT) was shown in laboratory studies to be more sensitive to small amounts of residual heparin than the ACT. Clinical evaluations confirmed that additional protamine is required in approximately 12% of cardiac surgical cases managed using the PRT system. Both the PDA and TT/HNTT provided useful postoperative assessment of the adequacy of heparin neutralization. The TT/HNTT had slightly improved heparin sensitivity even in the presence of significant fibrinogen loss. These point-of-care assays provide the opportunity to optimize heparin and protamine management in the cardiac surgery patient.
Mathematical modelling of extracorporeal circulation: simulation of different perfusion regimens
Authors: Bauernschmitt R , Naujokat E , Mehmanesh H , Schulz S , Vahl C F , Hagl S , Lange R 
Published: January 2013

Computer- and sensor-aided control of the heart-lung machine is considered a major goal for perfusion sciences for the next few years. At present, control of perfusion is achieved by surgeons, anaesthesiologists and perfusionists making short-term decisions, which leads to variations of the perfusion regimens between different centres and even between different teams in the operating theatre. As the basis for an integrated control of extracorporeal circulation (ECC), we proposed a mathematical model for simulating haemodynamics during pulsatile perfusion. This model was then modified to allow it to simulate the effects of different perfusion regimens on arterial haemodynamics and whole body oxygen consumption. The model was constructed on a PC using MATLAB/SIMULINK. The human arterial tree was divided into a multibranch structure consisting of 128 segments characterized by their particular physical properties. Peripheral branches were terminated by a resistance term representing smaller vessels like arterioles and capillaries. Flow and pressure were expressed by the intensity of current and voltage in an electrotechnical analogon; inductivity, resistance and capacitance were implemented according to the physical properties of the arterial tree and the rheology of blood. The effects of different perfusion regimens (pulsatility, flow amount, acid-base regulation) were studied. After introducing an input signal to the model, flow and pressure waves established themselves throughout the simulated arterial tree. During the simulation experiments, marked differences among different perfusion regimens were displayed by the model. Variations in acid-base management mainly influenced the distribution of perfusion: during simulation of low-flow perfusion (1.2 l/min/m2), cerebral blood flow was 6.2 ml/s using an alpha-stat regimen, while it was increased to 9.4 ml/s during pH-stat, caused by an implementation of reduced cerebral resistance. Whole body oxygen consumption was predominantly regulated by the perfusion rate. While central venous oxygen saturation was calculated to be 84.7% during simulation of high-flow perfusion (2.4 l/min/m2), it dropped to 70% during simulation of low-flow perfusion regimens. The model proved to be useful for a realistic simulation of different perfusion regimens. Therefore it can be considered a continuing step for the derivation of a ‘state’ observer leading to the realization of an automatically controlled heart-lung machine.
Cardioplegia flow dynamics in an in vitro model
Authors: Taft Kimberly J , Stammers Alfred H , Jones Clinton C , Dickes Melinda S , Pierce Michelle L , Beck Daniel J 
Published: January 2013

The flow of fluids in extracorporeal circuits does not conform to conventional Poiseuille mechanics which confounds calculating cardioplegia (CP) flow distribution. The purpose of this study was to quantify CP flow dynamics in a model simulating coronary atherosclerosis across varying sized restrictions. An in vitro preparation was designed to assess hydraulic fluid movement across paired restrictions of 51, 81 and 98% lumen reductions. Volume data were obtained at variable flow, temperature, viscosity and pressure conditions. CP delivered through 14- and 18-gauge (GA) conduits at 8°C and 100 mmHg infusion pressure revealed that both four to one and crystalloid CP solutions had significantly less total percentage flow through the 14-GA conduit, p < 0.0001 and p < 0.001, respectively. Overall, 4:1 CP exhibited the most favorable fluid dynamics at 8°C in that it delivered the highest percentages of total CP flow through the smaller lumen conduit. At both 8°C and 37°C delivery, blood CP resulted in the least homogeneous fluid distribution at all delivery parameters. The results in relation to blood viscosity indicate that, although the 8°C blood CP had a significantly greater viscosity than 37°C blood CP, it did not produce an effect in fluid distribution. These data show that increasing the cardioplegic solution hematocrit causes an inhomogeneous fluid distribution regardless of delivery temperature or infusion pressure.
Outcome analysis of coronary artery bypass grafting: minimally invasive versus standard techniques
Authors: Dickes Melinda S , Stammers Alfred H , Pierce Michelle L , Alonso Anselmo , Fristoe Lance , Taft Kimberly J , Beck Daniel J , Jones Clinton C 
Published: January 2013

Minimally invasive coronary artery bypass grafting (MIDCAB) procedures are purported to result in improvements in patient management over standard techniques. A comparative study was performed on risk-stratified patients treated with either technique. Following institutional review board approval, a retrospective random chart review was conducted on 27 MIDCAB and 37 standard coronary artery bypass grafting (CABG) patients who were operated on over a 12-month period at the University of Nebraska Medical Center. Risk stratification was accomplished by dividing the two patient populations, MIDCAB and ‘standard’, into one of four subgroups based on a preoperative risk score. Risk stratification was achieved by dividing the patient populations into one of four subgroups: good, fair, poor and high risk. Both groups received similar operations and surgical interventions, except for the inclusion of cardiopulmonary bypass (CPB). Approximately 200 parameters were collected and analyzed in the following categories: anthropometric, operative and postoperative outcomes. The MIDCAB group had a significantly lower number of vessels bypassed (2.0 ± 0.7 vs 3.4 ± 0.9, p < 0.0001). Total postoperative blood product transfusions trended higher in the standard group (6.1 ± 12.6 U) when compared to the MIDCAB patients (2.3 ± 5.5 U, p < 0.15), although not statistically significant. Postoperative inotrope use was significantly less in the MIDCAB group (19% vs 59%, p < 0.002). Ventilator time in the MIDCAB group was 10.5 ± 5.4 h vs 15.0 ± 12.3 h in the standard group ( p < 0.07). The MIDCAB group had an overall greater length of stay, but was only statistically different within the poor-risk subgroup (12.2 ± 10.7 vs 7.5 ± 3.9, p < 0.04). The results of this study show that when CPB is not utilized in treating patients undergoing CABG procedures, the benefits in regards to patient outcomes are unclear. This necessitates the need for further work when comparing outcomes for risk-stratified patients.
Effect of Trillium™ Biopassive Surface coating of the oxygenator on platelet count drop during cardiopulmonary bypass
Authors: Palanzo David A , Zarro Debra L , Montesano Ralph M , Manley Norman J , Quinn Michael , Elmore Barbara-Anne , Gustafson Patricia A , Castagna Joseph M 
Published: January 2013

The new Trillium™ Biopassive Surface is a coating designed to minimize the adsorption of protein and the attachment of cells. In previous studies, we were able to demonstrate that, by coating the bypass circuit with small amounts of albumin, the drop in circulating platelet count seen with the newer low-prime hollow-fiber membrane oxygenators is eliminated. A study was undertaken to compare the Avecor Affinity™ oxygenator with albumin in the prime with the Trillium-coated Affinity. Fifty-six patients undergoing nonemergency open-heart surgery were randomly divided into two groups. One group (Albumin) received the Affinity oxygenator with 10 ml of 25% albumin added to the pump prime. The other group (Trillium) received the Trillium-coated Affinity oxygenator. To normalize the data for the effects of hemodilution, the mean net platelet count drop on bypass was calculated for each group. The Albumin group had a net platelet count drop of 0.81 ± 9.78%, while the Trillium group had a drop of 1.58 ± 13.0%. There was no significant statistical difference between the two groups. From our investigation, we concluded that Trillium Biopassive Surface coating affords the Affinity oxygenator the same protective effects on circulating platelet counts as adding albumin to the prime.
Case report of severe bradycardia due to transdermal fentanyl
Authors: Hawley Pippa 
Published: January 2013

Background: This case report describes a patient who developed severe bradycardia due to transdermal fentanyl. There have been no prior case reports of this occurring in palliative care, but the frequency of association of fentanyl with bradycardia in the anesthesia setting suggests it may be more common than realized. Palliative care settings often have a policy of not routinely checking vital signs, and symptoms of bradycardia could be misinterpreted as the dying process. Case presentation: A patient with recurrent ovarian cancer was admitted with nausea and abdominal pain due to bowel obstruction and fever from a urinary tract infection. A switch from injectable hydromorphone to transdermal fentanyl resulted in symptomatic severe bradycardia within 36 h, without any other signs of opioid toxicity and with good analgesic effect. Case management: The fentanyl patch was removed. Atropine was not required. Case outcome: The patient made an uneventful recovery. Transdermal buprenorphine was subsequently used satisfactorily for long-term background pain control, with additional hydromorphone when needed. Conclusions: The delayed absorption of fentanyl via the transdermal route makes early identification of fentanyl-induced bradycardia key to prompt reversal. Patients with resting or relative bradycardia may be at higher than average risk.
Simple Method of Glenoid Bone Loss Calculation Using Ipsilateral Magnetic Resonance Imaging
Authors: Owens Brett D. , Burns Travis C. , Campbell Scot E. , Svoboda Steven J. , Cameron Kenneth L. 
Published: January 2013

Background: Current methods for estimating glenoid bone loss in patients with chronic shoulder instability include computed tomography imaging with 3-dimensional reconstruction, specialized computer software, and imaging of the contralateral shoulder. An ideal method of glenoid measurement would require only magnetic resonance imaging (MRI) of the injured shoulder. Purpose: To determine whether MRI measurement of glenoid height, as well as sex, could be used to estimate glenoid width in healthy subjects with no history of shoulder instability. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Bilateral shoulder MRIs were obtained in a healthy cohort of young athletes as part of the baseline assessment in a prospective cohort study. A musculoskeletal radiologist measured glenoid height and width using the sagittal MRI cuts. Univariate and multivariate regression analyses were performed to determine whether demographic and MRI measurements of the glenoid could be used to estimate glenoid width. Results: Of the 1264 shoulder MRIs evaluated, the mean glenoid width was 26.67 mm (±2.49 mm), and the mean glenoid height was 42.15 mm (±3.00 mm). There were significant differences between the 129 female glenoids and the 1035 male glenoids for both width (23.1 mm, 27.1 mm, respectively, P < .0001) and height (37.9 mm, 42.7 mm, respectively, P < .0001); however, the relationship between glenoid height and width was similar for both men and women. The glenoid width was found to correlate with the height measurement ( r = 0.56) for the entire cohort. Based on the results of linear regression analysis, controlling for the influence of sex, a formula was created that represents the relationship between these variables for male subjects: Glenoid Width = (1/3 Height) + 15 mm. Female patients are estimated with a formula that represents the same slope but a different intercept: W = 1/3 H + 13 mm. Conclusion: Significant differences in glenoid height and width were found by sex; however, the relationship between height and width was similar. These variables are correlated, and the resultant formula can be used to estimate the expected glenoid width in a patient with bone loss. This formula allows for easy calculation of the amount of glenoid bone loss with only a ruler and an MRI of the injured shoulder.
Predictors of Recurrent Instability After Acute Patellofemoral Dislocation in Pediatric and Adolescent Patients
Authors: Lewallen Laura W. , McIntosh Amy L. , Dahm Diane L. 
Published: January 2013

Background: Patellofemoral instability is common in the pediatric and adolescent population, yet prognosis after the first dislocation has been difficult to determine. Purpose: To describe the demographics of pediatric and adolescent patients with a first-time patellofemoral dislocation and to determine predictors of recurrent instability. Study Design: Case-control study; Level of evidence, 3. Methods: A search of the Mayo Medical Index database between 1998 to 2010 was performed, and 2039 patients were identified. Inclusion criteria were (1) age 18 years or younger, (2) no history of patellofemoral subluxation/dislocation of the affected knee, (3) radiographs within 4 weeks of the initial instability episode, and (4) a dislocated patella requiring reduction or convincing history/findings suggestive of acute patellar dislocation (effusion/hemarthrosis, tenderness along medial parapatellar structures, and apprehension with lateral patellar translation). Radiographs were evaluated for trochlear dysplasia (Dejour classification) and patella alta (Caton-Deschamps and Insall-Salvati indices). Skeletal maturity was graded based on the distal femoral and proximal tibial physes (open, closing, or closed). Results: A total of 222 knees (120 male [54.1%] and 102 female [45.9%]) in 210 patients with an average age of 14.9 years (range, 9-18 years), met the inclusion criteria. Twenty-four patients (10.8%) underwent early surgery. All others were initially treated nonoperatively. Of the 198 patients in this group, 76 (38.4%) had recurrent instability, and 39 (51.3%) of these required surgical treatment. Recurrent instability was associated with trochlear dysplasia ( P < .01). Patients with both immature physes and trochlear dysplasia had a recurrence rate of 69% (33/48), with a hazard ratio of 3.3. Age, sex, body mass index, and patella alta were not statistically associated with recurrent instability. Conclusion: Nonoperative treatment for first-time patellofemoral dislocation resulted in a 62% success rate. However, skeletally immature patients with trochlear dysplasia had only a 31% success rate with nonoperative management. Nearly half of patients with recurrent instability required surgical intervention to gain stability.
Effect of Role Ambiguity, Conflict and Overload in Private Hospitals’ Nurses’ Burnout and Mediation Through Self Efficacy
Authors: Dasgupta Prasanjit 
Published: January 2013

Background The motivation of this study was to investigate how role overload, role conflict and role ambiguity of nurses relate to burnout and the relationship of nurses’ efficacy to these three stressors and burnout in private hospitals. Patients in private hospitals incur higher expenditure with expectations for better care. Stressors serve as impediments in nursing care and burnout has deleterious effect, high self efficacy can mediate in the effects of stressors and burnout. Methods: Study has been carried out on nurses in three large private hospitals of Kolkata through set of instruments-Organizational Role Stress (Udai Pareek) to assess role conflict, overload and ambiguity, Oldenburg Burnout Inventory to assess the disengagement and exhaustion and Nursing Role Efficacy Scale (Udai Pareek) to assess role efficacy. Data have been analyzed through correlation and regression analysis. Results: According to the nurses’ view, the findings are as follows: Increase in role overload, role conflict, role ambiguity leads to an enhancement in disengagement, exhaustion. Enhancement in self efficacy leads to a reduction in role overload, role conflict, role ambiguity, and disengagement, exhaustion. Conclusion: For better patient care Health care Managers may try to reduce the stressors and enhance efficacy of the nurses, some practical suggestions have been made in these regard.
Ball or aerosol? Sin, soap and the pharmaceutical industry
Authors: Ratcliff Eric 
Published: January 2013

Objective: The purpose of this paper is to provoke careful and continuing reconsideration of the relationship between psychiatrists and the pharmaceutical industry through historical analysis of trends in the promotion of psychotropic drugs. Conclusions: Psychiatrists remain concerned about the relationship of the profession with the pharmaceutical industry. From examination of my own extended experience of that relationship (including as a former Royal Australian and New Zealand College of Psychiatrists General Councilor and chair of the Clinical Practice Advisory and Ethical Practice Committees), attention is drawn to the influence of the industry on the categorization and naming of drugs, attempts to propose target disorders and the obsolescence of established agents. Caution in accepting the role of ‘opinion leader’ is recommended but it remains important for psychiatrists to continue to ethically engage with the industry.
William Siegfried Dawson: a pioneering Australasian psychiatrist
Authors: Roxanas Milton 
Published: January 2013

Objective: The purpose of this paper was to consider the life and contribution of Professor William Siegfried Dawson (1891–1975) by examination of school, university and hospital reports and journal articles. Conclusions: Professor Dawson made a major contribution, through his academic and professional roles and leadership, to the firm establishment of psychiatry, psychiatric scholarship and psychiatric organisations in Australia.
ABT-199, a new Bcl-2–specific BH3 mimetic, has in vivo efficacy against aggressive Myc-driven mouse lymphomas without provoking thrombocytopenia
Authors: Vandenberg Cassandra J. , Cory Suzanne 
Published: January 2013

Key Points
ABT-199, a new Bcl-2–specific BH3 mimetic, is efficacious in vivo against mouse lymphomas without provoking thrombocytopenia. Treating mouse lymphomas with BH3 mimetic ABT-737 combined with bortezomib or purvalanol achieved long-term remission.
Comparison of population-averaged and cluster-specific models for the analysis of cluster randomized trials with missing binary outcomes: a simulation study
Authors: Ma Jinhui , Raina Parminder , Beyene Joseph , Thabane Lehana 
Published: January 2013

Abstracts

Background
The objective of this simulation study is to compare the accuracy and efficiency of population-averaged (i.e. generalized estimating equations (GEE)) and cluster-specific (i.e. random-effects logistic regression (RELR)) models for analyzing data from cluster randomized trials (CRTs) with missing binary responses.

Methods
In this simulation study, clustered responses were generated from a beta-binomial distribution. The number of clusters per trial arm, the number of subjects per cluster, intra-cluster correlation coefficient, and the percentage of missing data were allowed to vary. Under the assumption of covariate dependent missingness, missing outcomes were handled by complete case analysis, standard multiple imputation (MI) and within-cluster MI strategies. Data were analyzed using GEE and RELR. Performance of the methods was assessed using standardized bias, empirical standard error, root mean squared error (RMSE), and coverage probability.

Results
GEE performs well on all four measures — provided the downward bias of the standard error (when the number of clusters per arm is small) is adjusted appropriately — under the following scenarios: complete case analysis for CRTs with a small amount of missing data; standard MI for CRTs with variance inflation factor (VIF) <3; within-cluster MI for CRTs with VIF≥3 and cluster size>50. RELR performs well only when a small amount of data was missing, and complete case analysis was applied.

Conclusion
GEE performs well as long as appropriate missing data strategies are adopted based on the design of CRTs and the percentage of missing data. In contrast, RELR does not perform well when either standard or within-cluster MI strategy is applied prior to the analysis.