bluuebunny/crossref_metadata_2025 huggingface dataset:
Coagulation and Fibrinolysis in Preeclampsia and Neonates
Authors: Tanjung M. Thamrin , Siddik H. Djafar , Hariman Herman , Koh Stephen C.L.
Published: March 2006

Coagulation and fibrinolysis were determined in 67 Indonesian women admitted to the University Hospitals for delivery in Medan. They were diagnosed to be at term gestation (mean 39.3 ± 1.1 weeks) with moderate and severe preeclampsia (n=32) and in labor, and 8 had preterm labor (gestation mean 33.5 ± 2.6 weeks). Twenty-seven normal pregnant women in labor (gestation mean 39.7 ± 1.0 weeks) served as controls. Cord blood from 23 neonates from normal pregnancy and 31 neonates from preeclampsia was also evaluated. Preeclamptic women in labor showed further enhanced coagulation activation (F1+2) with raised urokinase-like plasminogen activator (u-PA) activity and reduced plasminogen activator inhibitor-2 (PAI-2) levels. In preterm preeclampsia, significantly reduced antithrombin III (ATIII) and PAI-2 levels with further elevated tissue-type PA (t-PA) antigen and plasminogen activator inhibitor-1 (PAI-1) antigen were seen compared to normal pregnancy. These would suggest a state of enhanced thrombin generation with elevated fibrinolytic/inhibitor proteins in preterm preeclampsia. The reduced PAI-2 levels seen in preeclampsia have been suggested to be associated with reduced placental function. Neonates born to mothers of either normal pregnancy or preeclampsia at term showed similar hemostatic changes with reduced fibrinogen, ATIII, t-PA, u-PA antigen, PAI-1 levels, and coagulation activation compared to their respective maternal plasma levels. No significant differences in hemostatic parameters studied between the neonates of both cohorts were seen, and this would suggest that the neonates were protected from the adverse effects of preeclampsia and their hemostatic system was physiologically balanced.
The Association between Fibrinogen, von Willebrand Factor, Antithrombin III, and D-dimer Levels and Survival Outcome by 36 Months from Ovarian Cancer
Authors: Koh Stephen C. L. , Khalil R. , Lim F -K , Ilancheran A. , Choolani M.
Published: March 2006

Thirty-five patients diagnosed to have ovarian cancer (early FIGO stage I/II n = 11, advanced FIGO stage III/IV, n = 24) were evaluated for hemostatic parameters relating to survival outcome by 36 months of disease. Systemic plasminogen activators and inhibitors were evaluated and we found no significant association with survival outcome and eventually only fibrinogen, von Willebrand Factor (vWF), antithrombin III (ATIII), and D-dimer levels were determined for their association with disease outcome by 12 months, 24 months, and 36 months. Twenty-four patients succumbed to the disease by 36 months (early n = 2, advanced n = 22). The 11 surviving patients (advanced n = 3, including one deceased at 52 months) is still living past 36 months and 82 months at the time of analysis. Elevated fibrinogen, vWF, and D-dimer together with reduced ATIII levels were found to be associated with poor survival outcome by 12 months of disease. Moreover, elevated vWF and D-dimer with reduced ATIII levels was strongly implicated with poor survival outcome by 36 months from ovarian cancer. The overall survival rate at 36 months from ovarian cancer was 31.4%. It is therefore suggested that fibrinogen, vWF, ATIII, and D-dimer levels be used together as prognostic markers for disease outcome especially in patients with advanced ovarian cancer within 36 months of disease. An expanded study is required to confirm these findings.
Effect of Various Genetic Polymorphisms on the Incidence and Outcome of Severe Sepsis
Authors: Sipahi Tansu , Pocan Hatice , Akar Nejat
Published: March 2006

Several genetic polymorphisms have been identified in patients with sepsis and severe sepsis, such as the tumor necrosis factor-α (TNF-α) and TNF-β genes, the interleukin-1 (IL-1) family, the IL-6, the IL-10, the CD-14, the Toll-like receptors, plasminogen activator inhibitor type 1, and the factor V 1691G-A mutations. In this study, the relationship between the TNF-α 308G/A, the IL-6-174 G/C, the PAI-1, the FVL, the EPCR, and the Cathepsin G (Ars 125 Ser) polymorphisms and the development and outcome of sepsis in pediatric patients was studied. TNF-α 308 G/A, PAI-1 4G/4G, and EPCR mutations influence the risk of severe sepsis in children. IL-6 174 G/C, FVL, and Cathepsin G (Ars 125 Ser) did not influence the incidence and mortality of severe sepsis.
Evaluation of a Rapid Automated Assay for Analysis of von Willebrand Ristocetin Cofactor Activity
Authors: Strandberg Karin , Lethagen Stefan , Andersson Kerstin , Carlson Margareta , Hillarp Andreas
Published: March 2006

A commercially available turbidometric assay has been evaluated for the measurement of von Willebrand factor ristocetin cofactor activity (VWF:RCo). The assay is simple, rapid, and can be cost-effectively performed on automated coagulation analyzers. This study’s aim is to illustrate the performance of the automated VWF:RCo assay and its capacity to identify patients with von Willebrand disease (VWD). By direct comparison with a conventional VWF:RCo assay, performed on an aggregometer, the concordance between the two assays was 96%. With minor modifications, the automated assay showed a detection level of 0.03 kIU/L with linearity to 2.00 kIU/L. The imprecision of the automated assay was reduced compared to the conventional assay procedure with CV of 6.8% at the 1.00 kIU/L level and 8.6% at the 0.30 kIU/L level. The automated VWF:RCo assay was also suitable as a screening test to detect VWD in patients investigated for the cause of an increased bleeding tendency. In this situation the automated VWF:RCo assay was tested simultaneously with an automated immunoassay for von Willebrand antigen. Receiver operating curves for the diagnosis of VWD showed a greater area under the curve for the automated VWF:RCo assay compared to the immunoassay, 0.98 vs. 0.94, although the difference did not reach significance. In conclusion, the modified automated VWF:RCo assay shows better precision, lower detection limit, is faster to perform with a lower cost per test compared to the conventional aggregometer based VWF:RCo activity method and is an alternative to an antigen immunoassay as a screening test for VWD.
Extreme Thrombocytosis: What Are the Etiologies?
Authors: Wiwanitkit Viroj
Published: March 2006

Increase platelet count or thrombocytosis, defined as a platelet count greater than or equal to 350 × 109/L, is a common hematologic aberration seen in complete blood cell count. Several etiologies are documented for thrombocytosis. Extreme thrombocytosis, defined as a platelet count greater than or equal to 1,000 × 109/L, is rarely seen in general practice. There are limited data on the etiology of this abnormality. Here, a retrospective investigation for the etiology of severe thrombocytosis was performed. Of the 3 included reports, 535 cases with extreme thrombocytosis were investigated for their etiologies. The 2 defined etiologies are secondary thrombocytosis (66.6%) and clonal thrombocytosis. Of those cases with clonal thrombocytosis, 93.8% had myeloproliferative disorders, and 6.2% had essential thrombocytosis. Concerning bleeding and vaso-occlusive complications, all cases had these complications. In this study, 7.9% of the cases with secondary thrombocytosis experienced bleeding and vaso-occlusive complications, while 17.1% of the cases with clonal thrombocytosis did.
PIA1/A2 Polymorphism of the Platelet Glycoprotein Receptor IIb/IIIIa and Its Correlation With Myocardial Infarction: An Appraisal
Authors: Wiwanitkit Viroj
Published: March 2006

Platelet glycoprotein (GP) IIb/IIIa is a membrane receptor for fibrinogen and von Willebrand factor. There is considerable controversy regarding the clinical role of the GPIIb/IIIa PIA1/A2 as a risk factor for myocardial infarction. A summative analysis is performed on the recent previous reports on the GPIIb/IIIa PIA1/A2 and its correlation to myocardial infarction. The metanalysis was performed to assess the correlation between the pattern of GPIIb/IIIa PIA1/A2 polymorphism and myocardial infarction. From 7 available case-control reports, 553 patients and 1,059 controls are evaluated. The overall frequencies of PIA2 allele for the patients and controls are 0.249 and 0.221, respectively. According to this study, 49.4% of subjects with PIA2 allele have myocardial infarction while 39.5% of subjects without PIA2 allele have cerebrovascular disease. From overall risk estimation, the subjects with PIA2 alleles have a 1.1 times higher risk to have myocardial infarction. According to this analysis, it is proposed that the pattern of GPIIb/IIIa PIA1/A2 polymorphism does not represent a useful marker of increased risk for myocardial infarction. In addition, the lack of association between the pattern of GPIIb/IIIa PIA1/A2 polymorphism and ethnicity of the patients was demonstrated in this study.
Re-treatment of Chronic Idiopathic Thrombocytopenic Purpura With Rituximab: Literature Review
Authors: Perrotta Augustine L.
Published: March 2006

The aim of this literature review was to identify from published reports, the characteristics and response to rituximab of nine patients with chronic idiopathic thrombocytopenic purpura who had been re-treated after responding to an initial course of therapy. The female/male ratio of re-treated patients was eight, suggesting selection or their suitability for treatment because the female/male ratio of 95 initially treated patients in all published reports between December 1998 and June 2003 was 2. Almost three times as many females responded to the first course of rituximab. All second responses, where recorded, were complete despite two previous partial responses and one minor response. The duration of the second response was at least as durable and more so than the first. Of the nine re-treated patients, the two failures had not undergone splenectomy, yet had achieved a complete response to the first course. All four patients who had previously responded to intravenous immunoglobulin responded to both the initial and subsequent course of rituximab. The influence of prior splenectomy, response to intravenous immunoglobulin, and distinctive patterns of time course until platelet response suggest that there might be different mechanisms of response to rituximab.
Nonlinear Hearing Aids and Verification of Fitting Targets
Authors: Fabry David A.
Published: March 2006

This paper addresses the issue of initial verification of hearing aid gain and output for nonlinear hearing aids. Specifically, “urban legend” has it that nonlinear hearing aids with digital noise reduction circuitry may not be accurately measured using functional gain and/or probe microphone measures. Discussed are the advantages and disadvantages of both measurement strategies, and how they may be used to “acoustically match” hearing aids to individual patients. An evaluation protocol that employs both optimal aided thresholds and probe microphone measurements to assess gain, output, and audibility in hearing-impaired patients.
Adaptive Dynamic Range Optimization (ADRO): A Digital Amplification Strategy for Hearing Aids and Cochlear Implants
Authors: Blamey Peter J.
Published: March 2006

Adaptive dynamic range optimization (ADRO) is an amplification strategy that uses digital signal processing techniques to improve the audibility, comfort, and intelligibility of sounds for people who use cochlear implants and/or hearing aids. The strategy uses statistical analysis to select the most information-rich section of the input dynamic range in multiple-frequency channels. Fuzzy logic rules control the gain in each frequency channel so that the selected section of the dynamic range is presented at an audible and comfortable level. The ADRO processing thus adaptively optimizes the dynamic range of the signal in multiple-frequency channels. Clinical studies show that ADRO can be fitted easily to all degrees of hearing loss for hearing aids and cochlear implants in a direct and intuitive manner, taking the preferences of the listener into account. The result is high acceptance by new and experienced hearing aid users and strong preferences for ADRO compared with alternative amplification strategies. The ADRO processing is particularly well suited to bimodal and hybrid stimulation which combine electric and acoustic stimulation in opposite ears or in the same ear, respectively.
Health-Related Quality of Life and Hearing Aids: A Tutorial
Authors: Abrams Harvey B. , Chisolm Theresa H. , McArdle Rachel
Published: March 2006

Health-related quality-of-life (HRQoL) instruments measure the impact of a disorder and treatment on several attributes that are thought to constitute the self-perceived health status of an individual. This tutorial reviews the conceptual framework of HRQoL, including the challenges associated with defining and measuring HRQoL, specifically as it applies to audiologic care. A relatively new instrument, the World Health Organization-Disability Assessment Schedule II, will be discussed as a potentially valuable instrument to measure the impact of hearing loss and hearing aid intervention on self-perceived HRQoL.
Management of the Ascending Aorta in Routine Cardiac Surgery
Authors: Menkis Alan Harold
Published: March 2006

It is well known that subtle neurologic and neuropsychologic adverse effects are associated with cardiac surgery. Microgaseous emboli may arise from the cardiac pulmonary bypass apparatus; however, most particulate emboli arise from the ascending aorta. Atherosclerosis of the ascending aorta may effect up to 38% of cardiac surgical patients greater than 50 years of age. In addition to avoiding cardiopulmonary bypass with off-pump procedures, avoiding manipulation of the ascending aorta in any way is also associated with a reduction in embolic complications. Epiaortic scanning is the most accurate way to assess the location and severity of atheromata in the ascending aorta. Management of the atheromatous ascending aorta may include changes to cannulation options for cardiopulmonary bypass, such as femoral or axillary cannulation. Complete avoidance of the cross-clamp may be entertained. Aorta cannulae incorporate a number of filtration and deflection devices that may offer some protection to the brachiocephalic vessels. In some cases, replacement of the ascending aorta under deep hypothermic circulatory arrest is appropriate. Avoidance of the ascending aorta by using arterial revascularization as sequential or Y grafts, or placing proximal anastomoses on the subclavian arteries, may allow for complete revascularization without touching the ascending aorta. A full appreciation of the information obtained with epiaortic scanning or transesophageal echocardiography allows for decisions to be made to tailor each procedure to the patient's unique needs and circumstances for optimal outcomes.
Human Auditory Evoked Potentials in the Assessment of Brain Function During Major Cardiovascular Surgery
Authors: Rodriguez Rosendo A.
Published: March 2006

Focal neurologic and intellectual deficits or memory problems are relatively frequent after cardiac surgery. These complications have been associated with cerebral hypoperfusion, embolization, and inflammation that occur during or after surgery. Auditory evoked potentials, a neurophysiologic technique that evaluates the function of neural structures from the auditory nerve to the cortex, provide useful information about the functional status of the brain during major cardiovascular procedures. Skepticism regarding the presence of artifacts or difficulty in their interpretation has outweighed considerations of its potential utility and noninvasiveness. This paper reviews the evidence of their potential applications in several aspects of the management of cardiac surgery patients. The sensitivity of auditory evoked potentials to the effects of changes in brain temperature makes them useful for monitoring cerebral hypothermia and rewarming during cardiopulmonary bypass. The close relationship between evoked potential waveforms and specific anatomic structures facilitates the assessment of the functional integrity of the central nervous system in cardiac surgery patients. This feature may also be relevant in the management of critical patients under sedation and coma or in the evaluation of their prognosis during critical care. Their objectivity, reproducibility, and relative insensitivity to learning effects make auditory evoked potentials attractive for the cognitive assessment of cardiac surgery patients. From a clinical perspective, auditory evoked potentials represent an additional window for the study of underlying cerebral processes in healthy and diseased patients. From a research standpoint, this technology offers opportunities for a better understanding of the particular cerebral deficits associated with patients who are undergoing major cardiovascular procedures.
Atrial Fibrillation After Cardiac Surgery: Pathophysiology and Treatment
Authors: Palin Christopher A. , Kailasam Rajagopal , Hogue Charles W.
Published: March 2006

Atrial fibrillation (AF) occurs in 25% to 60% of patients after cardiac surgery. It is most consistently associated with advanced age and valvular heart operations. Despite improving knowledge of the pathophysiology of chronic AF, postoperative AF remains an obstinate clinical problem. It is associated with an increased risk of stroke, longer hospital stay, and higher hospital expenditure. Consequently, there has been great interest in strategies to prevent and treat this arrhythmia. Treatment for postoperative AF may require immediate electrical cardioversion for hemodynamically unstable patients. Heart rate control is useful in most patients, with anticoagulation considered after 48 hours. Antiarrhythmic therapy is often effective in restoring sinus rhythm but its use needs to be balanced against the patient's risk of proarrhythmic side effects such as torsade de pointes.
“Other” Neurologic Complications After Cardiac Surgery
Authors: Grocott Hilary P. , Clark Jeffrey A. , Homi H. Mayumi , Sharma Ajeet
Published: March 2006

Compared to the neurologic morbidity of stroke and cognitive dysfunction, “other” neurologic complications involving injuries to the brachial plexus, phrenic nerve, cranial nerves, other peripheral nerves, as well as the visual pathways, have been disproportionately underrepresented in the cardiac surgery and anesthesiology literature. These injuries are often missed in the early postoperative period when attention is focused principally on recovery from the acute trespass of cardiac surgery and cardiopulmonary bypass. However, when these problems do become apparent, they can cause considerable discomfort and morbidity. An overview of the current concepts of injury mechanisms/etiology, diagnosis, prognosis, and when possible, prevention of these injuries is presented.
Fast-Track Cardiac Anesthesia: Choice of Anesthetic Agents and Techniques
Authors: Myles Paul S. , McIlroy David
Published: March 2006

Fast-track cardiac anesthesia (FTCA) incorporates early tracheal extubation, decreased length of intensive care unit (ICU) and hospital stay, and (ideally) should avoid or reduce complications to safely achieve cost-savings. A growing body of evidence from randomized trials has identified many anesthetic interventions that can improve outcome after cardiac surgery. These include new short-acting hypnotic, opioid, and neuromuscular blocking drugs. An effective FTCA program requires the appropriate selection of suitable patients, a lowdose opioid anesthetic technique, early tracheal extubation, a short stay in the ICU, and coordinated perioperative care. It is also dependent on the avoidance of postoperative complications such as excessive bleeding, myocardial ischemia, low cardiac output state, arrhythmias, sepsis, and renal failure. These complications will have a much greater adverse effect on hospital length of stay and healthcare costs. A number of clinical trials have identified interventions that can reduce some of these complications. The adoption of effective treatments into clinical practice should improve the effectiveness of FTCA.
The Impact of Intraoperative Echocardiography on Clinical Outcomes Following Adult Cardiac Surgery
Authors: Fox John , Glas Kathryn , Swaminathan Madhav , Shernan Stanton
Published: March 2006

Over the past 30 years, intraoperative echocardiography has become an invaluable diagnostic tool and monitor of cardiac performance for the management of cardiac surgical patients. The essential information provided by intraoperative echocardiography regarding hemodynamic management, cardiac valve function, congenital heart lesions, and great vessel pathology has contributed to its widespread popularity. Numerous investigations have been conducted in an attempt to specifically demonstrate a beneficial impact of intraoperative echocardiography in cardiac surgery. However, there is a relative paucity of data derived from prospective trials in which the use of intraoperative echocardiography has been randomized among various cardiac surgical patient populations to formally ascertain, rather than simply infer, its putative impact on perioperative decision-making and clinical outcomes. Ironically, the popularity of intraoperative echocardiography has imposed ethical limitations on performing randomized trials in patient populations for whom significant benefit has been previously inferred. Nonetheless, significant evidence has been published to support its almost universal acceptance as an important perioperative diagnostic tool and monitor for cardiac surgical patients. This review focuses on the impact of intraoperative echocardiography on clinical outcomes in the more common adult cardiac surgical scenarios, including coronary artery bypass graft surgery, mitral and aortic valve surgery, and in evaluating the intrathoracic aorta.
Evidence Based Coagulation Monitors: Heparin Monitoring, Thromboelastography, and Platelet Function
Authors: Shore-Lesserson Linda
Published: March 2006

The hemostatic management of patients undergoing cardiac surgery is a unique challenge. Since its inception, cardiopulmonary bypass (CPB) has required meticulous attention to maintaining adequate anticoagulation. New anticoagulants and alternative monitoring techniques present an opportunity to investigate potential advances in the area of anticoagulation for CPB. Hemostasis after CPB is still a vexing problem, and the addition of antiplatelet medication to the platelet defect already incurred during CPB has led to hemorrhagic complications in cardiac surgery. The two opposing processes of anticoagulation and hemostasis must be managed carefully and modified with respect to the patient's hematologic status and desired hemostatic outcome. Cardiac surgical patients consume a much larger fraction of perioperative blood transfusions than the percentage of the surgical population they represent. Thus, during CPB, careful attention must be paid to optimal anticoagulation, platelet quiescence, biocompatible circuitry and interventions, and to monitoring hemostasis. The multifactorial etiology of the CPB-induced hemostatic defect requires a multimodal approach to blood conservation and hemostasis monitoring, including heparin maintenance and sophisticated point-of-care hemostasis monitoring. Each technology has its own attributes and each may be suitable for different populations based upon the expected defects being measured. This article reviews the evidence supporting the use of point-of-care monitors in coagulation and hemostasis management in cardiac surgical patients.
Embolic Factors Associated with Cardiac Surgery
Authors: Stump David A.
Published: March 2006

Macro and microemboli can both cause significant neurologic dysfunction. The traditional belief in cardiac surgery was that the damage perpetrated by an embolus was caused by the occlusion of an arterial branch, resulting in an ischemic event and subsequent infarction. However, ongoing research has demonstrated that the mere passage of a deformable embolus (air, lipid, or semi-solid clot) will disrupt the endothelium as it is extruded through the vessel. A cascade of events follows endothelial irritation. In the closed environment of the brain, a disruption of the blood-brain barrier has been demonstrated after the passage of lipid microemboli. A significant breakdown of the blood-brain barrier causes marked brain swelling, increased intracranial hypertension, and a possible increase in the size of the lesions associated with larger occlusive emboli. Gaseous microemboli are also a well-documented endothelial irritant and can cause significant brain dysfunction. It is important to avoid delivering emboli of any size or composition to the cerebral vasculature in order to reduce the impact of cardiac surgery on the brain.
Reducing Cerebral Emboli During Cardiopulmonary Bypass
Authors: Prasongsukarn Kriengchai , Borger Michael A.
Published: March 2006

Neurologic injury is a common complication of cardiac surgery and is associated with significant morbidity, mortality, and resource utilization. The incidence varies widely according to the definition used, patient age, and complexity of surgery. The manifestations of neurologic injury are broad, ranging from subtle neurocognitive dysfunction to frank stroke. An increasing amount of evidence points to cerebral embolization during cardiopulmonary bypass (CPB) as the principal etiologic factor of these neurologic complications. Cerebral emboli may be composed of atherosclerotic debris, calcium, air, fat, platelet thrombi, or CPB tubing. Advancements in perfusion technology, CPB techniques and surgical strategies may lead to a reduction in neurologic injury during cardiac surgery. In the current paper, we discuss the pathophysiology of neurologic injury after cardiac surgery and methods of reducing cerebral embolization. Reducing emboli and neurologic injury during CPB requires a multidisciplinary approach that includes several simple diagnostic and therapeutic strategies. Reducing cerebral emboli should be a major goal for future research in the fields of cardiac anesthesia, surgery and perfusion.
Glucose and Insulin Influences on Heart and Brain in Cardiac Surgery
Authors: Quinn David W. , Pagano Domenico , Bonser Robert S.
Published: March 2006

The elective global ischemia of on-pump coronary artery bypass surgery contributes to the incidence of postoperative mortality, complications, and use of resources. In addition to cardiopulmonary bypass and techniques for myocardial protection such as aortic cross clamp, ventricular fibrillation, and cardioplegia, the administration of systemic glucose-insulinpotassium (GIK) in the perioperative period may act as both a metabolic modulator and potential inodilator. GIK may therefore serve to protect the myocardium and promote adequate cardiac and hemodynamic performance that would improve patient recovery. Cell, tissue, and animal experiments have determined a number of mechanisms of action by which this may be achieved, with increasing focus on insulin as the key component. The original concepts centered on GIK during or after ischemia switching metabolism away from that based on nonesterified fatty acids toward a more favorable glucose-based metabolism and thus improving the efficiency of adenosine triphosphate production and glycogen preservation. Insulin's ability to reduce intracellular fatty acid metabolism may also reduce cellular membrane damage. More recently other mechanisms have also been suggested, including osmotic, oxygen free radical scavenging, and antiapoptotic and anti-inflammatory effects. However, trials that have examined the role of GIK in cardiac surgery have been small, open label, and involved a wide variety of regimens. They have demonstrated improved glycogen preservation, reduced infarct size, reduced incidences of dysrhythmias, need for inotropic agents, and low cardiac output state, and overall reduced lengths of stay. The perceived need to achieve strict blood glucose control to reduce neurologic injury and improve overall mortality have conflicted with its practical difficulties, particularly during cold cardiopulmonary bypass, and the exact role of supplemental glucose administration and resulting hyperglycemia require re-examination.
Clinical Predictions and Decisions to Perform Cardiac Surgery on High-Risk Patients
Authors: Dupuis Jean-Yves
Published: March 2006

The proportion of high-risk patients undergoing cardiac surgery has increased steadily over the last two decades. Many of those patients have a catastrophic postoperative course and use hospital resources in a proportion that largely outweighs their number. Consequently, the appropriateness of invasive and intensive interventions in those patients has been questioned. If futility of care were predictable preoperatively, cardiac surgery would probably be denied to many highrisk patients. Logistic regression has been used to develop many complex predictive models to identify high-risk patients and predict their outcome; however, those models do not provide much more discrimination than clinical judgment alone. Moreover, with continuous improvement in medical care all risk models lose their calibration over time. As a result, they often overestimate the probabilities of poor outcome in the individual patients. Many high-risk cardiac surgical patients require a prolonged stay in the intensive care unit (ICU). The analysis of small cohorts of patients who had a prolonged postoperative stay in the ICU shows that 50% and 40% of them are still alive at 1- and 2-year follow-up, respectively; and most survivors report a good quality of life. Considering the limitations of predictive risk models and the satisfaction of cardiac surgical patients who survive after a prolonged ICU stay, it is reasonable to recognize that cardiac surgery should rarely be denied to high-risk patients unless technically unfeasible, and clinical predictions should have only a marginal role in the decision to operate on those patients.
Ventricular Assist Devices and Anesthesia
Authors: El-Magharbel Ibrahim
Published: March 2006

Ventricular assist devices (VADs) have revolutionized longterm care for patients with congestive heart failure. These patients represent about 1% of the adults in the United States, considering that heart failure is a contributing factor in more than 250,000 deaths annually. It has been estimated that about 60,000 patients per year in the United States could benefit from heart transplantation or long-term mechanical support. Because of the short supply of donor hearts for transplant, assist devices have become of great value. At least four assist devices are clinically available, and two other devices are being investigated. Because cardiopulmonary bypass is required for implantation of these devices, anesthetizing these critically compromised patients requires extensive monitoring, skillful anesthetic management, and expert postoperative care.
A Report of a Case: Anesthetic Management of a Parturient with Severe Thrombotic Stenosis of a Mechanical Aortic Valve—An Exercise in Coordination of Subspecialties
Authors: Inyang Asuquo N. , Jackson Mark , Kumar Ashok , Nychka Andre , Leyvi Galina , Zhuravlev Ilya , Plestis Konstadinos , Wasnick John
Published: March 2006

The pregnant woman with valvular heart disease presents significant challenges to the obstetric, anesthesiology, and cardiology teams. Although successful outcomes for both mother and fetus are possible with coordinated medical care, the patient with a prosthetic valve who requires systemic anticoagulation provides a dilemma of insufficient anticoagulation leading to valve thrombosis versus the risks of maternal perinatal hemorrhage or fetal effects from oral or parenteral anticoagulants. This case report describes the peripartum management of a patient at 27 weeks' gestation with thrombus ona prosthetic aortic valve.
Simulation in Cardiothoracic and Vascular Anesthesia Education: Tool or Toy?
Authors: Lake Carol L.
Published: March 2006

The use of simulators in cardiothoracic and vascular anesthesia runs the gamut from standardized patients and parttask trainers to full-scale high-fidelity human patient simulators. The use of simulation to teach medical students, anesthesiology residents, board-certified anesthesiologists with subspecialty interests, hospital administrators, attorneys, and the lay public is still evolving as educational research evaluates the use of simulation and health professional educators struggle to define its role and value. This article provides a general overview of the field and attempts to critically evaluate what is and what is not scientifically determined about simulation and simulators.
Simulation-Based Education for Cardiac, Thoracic, and Vascular Anesthesiology
Authors: Sinz Elizabeth
Published: March 2006

Simulation has been used for medical teaching and testing for at least four decades in some form, such as that used for cardiopulmonary resuscitation training; however, new technology applied to medical and procedural training has recently led to a marked increase in the use of simulation-based instruction. Educational theory has further supported simulation for medical education and procedural training. Simulation-based testing to demonstrate competence with new procedures is already required by the US Food and Drug Administration for one angiographicallyplaced device, and it is likely that simulationbased credentialing for procedures will be increasingly prevalent. Anesthesiologists, like other physicians, may be credentialed or certified based on their performance in a simulated environment in the future. This review describes some of the current simulation-based education techniques related to cardiovascular and thoracic anesthesiology. Additional discussion covers some of the applicable educational theory and the expected future uses of simulation modalities in healthcare education, testing, and practice.
The Effect of Pain on Leukocyte Cellular Adhesion Molecules
Authors: Griffis Charles A. , Compton Peggy , Doering Lynn
Published: March 2006

The psychophysiological phenomenon of pain is of tremendous concern to nurses because of its potential to adversely affect the mental, emotional, and physical health of patients. Increasingly appreciated is the ability of pain to influence immune variables including enumerative and functional measures of leukocyte subsets. In this review, a theoretical model of the role of pain in producing positive changes in the expression of leukocyte cellular adhesion molecules is developed. The model is based on a conceptualization of pain as a perturbing influence on the complex web of neuroendocrine-immune relationships that regulate leukocyte migration. Findings from multiple lines of research are reviewed, including the neurophysiology and psychophysiology of pain, neuroendocrine and proinflammatory cytokine responses to painful stress, animal models linking pain to proinflammatory central immune activation, and pain-specific neurogenic inflammation. Relevant findings are synthesized to develop the physiological pathways from the perspective that pain may alter the balance of this multidirectional system in a proinflammatory direction. Clinical implications and suggestions for further research in the area of painful stress-related inflammation are offered.
Clinical Benefit of Carotid Endarterectomy Based on Duplex Ultrasonography
Authors: Kasper Gregory C. , Lohr Joann M. , Welling Richard E.
Published: March 2006

Carotid endarterectomy has been shown to significantly reduce the risk of stroke caused by carotid artery stenosis in selected patients. Limiting the morbidity and costs of this process without increasing the risks should further improve the benefits of this procedure. Results were prospectively collected from 123 consecutive carotid endarterectomies performed at a community teaching hospital. All patients underwent duplex ultrasonography for preoperative evaluation. Catheter angiography was used on a selective basis. Preferential use of regional anesthetic and selective use of the intensive care unit were applied. The mortality, morbidity, complications, and costs were then compared for the group receiving only preoperative duplex ultrasonography with those undergoing catheter angiography preoperatively. Age, comorbid risk factors, indications for carotid endarterectomy, and incidence of stroke were similar in both patient groups. The rates of mortality, morbidity, and stroke for carotid endarterectomy were low (mortality 0%, morbidity 6.5%, stroke 0.8%). For preoperative evaluation all patients underwent duplex ultrasonography (100%) and 28 (23%) underwent preoperative catheter angiography in addition to duplex ultrasonography. The complication rate associated with catheter angiography was 6/28 (21%). Complications included groin hematoma (7%), pseudoaneurysm (3.6%), bradycardia (7%), and unstable angina (3.6%). Costs for duplex ultrasonography averaged $165 and additional costs incurred by the use of catheter angiography averaged $4,200. Intraoperative assessment of the carotid endarterectomy site did not change based on the use of preoperative catheter angiography. Morbidity, mortality, and stroke rates were the same for the 2 groups. The preoperative use of duplex ultrasonography for the sole evaluation in carotid endarterectomy is well established. The use of preoperative catheter angiography is still preferred by a subset of surgeons. The use of catheter angiography is associated with significant morbidity and additional costs when compared to performing carotid endarterectomy based solely on preoperative duplex ultrasonography. The added costs and morbidity of angiography increase the societal cost of this procedure without significant clinical improvement in patient outcome.
The Effects of Glucose-Insulin-Potassium Solution and BN 52021 in Intestinal Ischemia-Reperfusion Injury
Authors: Aldemir Mustafa , Gürel Ahmet , Büyükbayram Hüseyin , TaÁyildiz Ibrahim
Published: March 2006

The objective of this study was to investigate effects of glucose-insulin-potassium (GIK) solution and BN 52021, a platelet-activating factor antagonist, on intestinal ischemiareperfusion injury. Fifty male Sprague-Dawley rats (200–225 g) were divided into 5 groups each containing 10 rats; group SO, sham operation group; group I, mesenteric ischemia group (for 30 minutes); group R, ischemia plus reperfusion (for 60 minutes); group BR, ischemia-reperfusion plus BN 52021; group GR, ischemia-reperfusion plus GIK solution. Samples for malondialdehyde (MDA) and ileum (for mucosal injury score) were obtained. The mucosal injury scores of group R were significantly higher than those of group I (4 ±0.20 and 3 ±0.16, respectively, p<0.0001). The scores of groups BR and GR were significantly lower than those of group R (p<0.0001 and p<0.0001, respectively). When it was compared with the injuries in BR and GR groups, similar results were obtained in both groups (p=0.190). Mean MDA levels of group R were significantly higher than those of group I, BR and GR (131.33 ±3.99 nmol/g, 93.74 ±3.22 nmol/g, 104.81 ±2.56 and 100.34 ±5.30, respectively, p<0.0001). MDA levels of group BR and GR were significantly lower than those of group I (p<0.0001 and p=0.003, respectively). These observations suggest that treatment with GIK solution and BN 52021 before reperfusion and during reperfusion period may be useful in decreasing intestinal reperfusion injury.
Noninfectious Saccular Abdominal Aortic Aneurysm
Authors: Minor Michael E. , Menzoian James O. , Raffetto Joseph D.
Published: March 2006

Saccular aortic aneurysms are eccentrically shaped and are commonly thought to be the consequence of infection of the aorta. However, saccular-type aneurysms can be found independent of any clinical or subclinical infection and can be associated with a penetrating aortic ulcer. Moreover, penetrating aortic ulcers have been described in the thoracic aorta, but there is a paucity of any documentation of this clinical and pathologic entity occurring in the abdominal aorta. The authors describe 2 cases of symptomatic, penetrating atherosclerotic ulcers of the abdominal aorta causing saccular, noninfectious abdominal aortic aneurysms.
Diagnostic Options in Assessing Abdominal Aortic Endograft Infection
Authors: Pringle Timothy , Muck Patrick , Lohr Joann , Thompson Wendy , Kasper Gregory C. , Welling Richard E.
Published: March 2006

Endovascular treatment of aortic aneurysms has gained widespread popularity in recent years. Stent grafts have emerged as another option in the surgeon's armamentarium in the treatment of aneurysmal disease. The infectivity of endovascular grafts and therapy for associated graft infections is unknown. Aortic graft infections have the potential for disastrous complications. This report presents a 72-year-old woman with persistent fever and an infected aortic stent graft in the early postoperative period.
Pseudoaneurysm of the Aortic Arch After Aortosubclavian Bypass Treated with Endoluminal Stent Grafting
Authors: Thompson Charles S. , Rodriguez Julio A. , Ramaiah Venkatesh G. , Olsen Dawn , Diethrich Edward B.
Published: March 2006

This paper describes a case of aortic arch pseudoaneurysm treated with stent graft 2 years after aortosubclavian bypass repair of a subclavian artery aneurysm. An 84-year-old man presented with back pain. Two years before, he had had a left subclavian artery aneurysm repaired with aortosubclavian bypass. Upon examination by computed tomography (CT) scan and angiography he was found to have a bovine arch configuration, a 7-centimeter pseudoaneurysm arising from the stump of the native subclavian artery, a patent aortosubclavian bypass, and a left hemothorax. A 37 mm by 10 mm Gore Excluder thoracic graft was introduced into the right femoral artery cutdown and deployed across the arch, excluding the pseudoaneurysm and preserving the brachiocephalic vessels. Follow up CT scan at 1 year shows exclusion of the pseudoaneurysm. The patient continues to do well 1 year after implantation without evidence of endoleak. In the presence of unusual anatomical characteristics, endoluminal stent graft repair can be successfully performed across the aortic arch.
Adjuncts to Improve Patency of Infrainguinal Prosthetic Bypass Grafts
Authors: Moawad John , Gagne Paul
Published: March 2006

The superiority of autologous venous conduit for infrainguinal arterial bypass has been well documented, especially when the bypass extends below the knee or to the tibial arteries. Nevertheless, when adequate autologous vein is not available, prosthetic bypasses (eg, polytetrafluoroethylene [PTFE] or Dacron) are often used in limb-salvage situations. The inferior long-term patency of these infrainguinal prosthetic bypasses has been documented by a number of studies. One such study reported a prospective multicenter randomized trial with only a 12% primary patency for infrapopliteal prosthetic bypasses after 4 years. Another study reported a similar experience with infragenicular bypasses with PTFE for limb salvage even for above-knee (27%, 5 year) and below-knee (25%, 5 year) femoral-popliteal bypasses. The reported PTFE graft patency was consistently inferior to that achieved with autologous vein for limb salvage. Dacron grafts appear to have similar patency rates to PTFE. In an attempt to improve prosthetic graft patency, a number of surgical and medical adjuncts have been developed. In this review, the authors discuss these adjuncts and their impact on infrainguinal prosthetic graft patency.
Critical Appraisal of Cardiac Risk Stratification Before Elective Vascular Surgery
Authors: Back Martin R. , Schmacht Dale C. , Bowser Andrew N. , Stordahl Norma , Cuthbertson David , Johnson Brad L. , Bandyk Dennis F.
Published: March 2006

This study was undertaken to evaluate the efficacy of the cardiac risk stratification protocol proposed by the American College of Cardiology/American Heart Association (ACC/AHA) in predicting cardiac morbidity and mortality associated with elective, major arterial surgery. Cardiac risk stratification using ACC/AHA guidelines was done on 425 consecutive patients before 481 elective cerebrovascular (n=146), aortic/inflow (n=166), or infrainguinal (n=169) procedures at an academic Veterans Affairs Medical Center. Cardiac risk was stratified as low, intermediate, or high based on clinical risk factors, such as, Eagle criteria, history of cardiac intervention, patient functional status, results of noninvasive cardiac stress testing, and coronary angiography with coronary revascularization performed when appropriate. Outcomes (myocardial infarction, unstable angina, congestive heart failure, ventricular arrhythmia, cardiac death, and mortality) within 30 days of surgery were compared between the various risk stratification groups. Univariate and multivariate analyses were used to identify clinically useful prognostic variables from the preoperative cardiac evaluation algorithm. Overall mortality (1.7%), cardiac death (0.4%), and adverse cardiac event (4.8%) rates were low, but cardiac death and morbidity were increased (p<0.05) in high-risk stratified patients (3.4%, 11.9%) compared to intermediate (0%, 2.8%) and low (0%, 4.0%) cardiac risk groups. The presence of 3-vessel angiographic coronary artery occlusive disease was an independent predictor of cardiac morbidity, while inducible ischemia by cardiac stress imaging was not. Previous coronary revascularization was associated with increased mortality as was the development of a non-cardiac complication. Cardiac risk assessment identified 78 (18%) patients with indications for coronary angiography. Angiographic findings resulted in coronary artery intervention (9-angioplasty; 4-bypass grafting) in 13 (3%) patients who experienced no adverse cardiac events after the planned vascular surgery (15 procedures). Cardiac risk stratification using ACC/AHA guidelines can predict adverse cardiac events associated with elective vascular surgery; however, protocol modification by increased reliance on Eagle criteria and less use of cardiac stress testing can improve identification of the “highest risk” patients who may benefit from prophylactic coronary intervention.
Endovascular Treatment of the Thoracic Aorta
Authors: Bush Ruth L. , Lin Peter H. , Lumsden Alan B.
Published: March 2006

Open surgical repair has been considered the mainstay of therapy for thoracic aortic aneurysms, both elective and emergency procedures alike. Recent advances in endovascular technology have made endovascular stentgraft placement a therapeutic modality that is minimally invasive and potentially a safer treatment for aneurysmal disease of the descending thoracic aorta. Moreover, this technology may be appropriate for other diseases of the thoracic aorta, including traumatic disruptions and dissections. There appears to be an increase in the diagnosis, and therefore incidence, of these various thoracic aortic pathologies, owing both to improvement in imaging capabilities and longer life expectancies. In distinction to endovascular repair of infrarenal aortic aneurysms, the evolution of thoracic stentgrafts has progressed more slowly as there has yet to exist a clinically proven device after 10 years of clinical trials. However, the enthusiasm for this technology persists, for it may indeed hold the potential for the greatest patient benefit as conventional open surgical repair continues to offer serious morbidity and mortality rates. This paper reviews the current status of thoracic aortic stentgrafts, including recent clinical studies, device failures and refinements, and future directions.