Seminars in cardiothoracic and vascular anesthesia
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Semin Cardiothorac Vasc Anesth · Dec 2010
ReviewCardiac output monitoring: is there a gold standard and how do the newer technologies compare?
As a principal determinant of oxygen delivery and of blood pressure, cardiac output (CO) represents an important hemodynamic variable. Its accurate measurement, therefore, is important to the clinician caring for critically ill patients in a variety of care environments. ⋯ The last decade has seen the introduction of several such devices into the clinical arena. This article will serve to give a brief review of the history of CO measurement, to provide a discussion of the measurement of accuracy as it relates to CO measurement, and to discuss some of the newer methods and devices for CO measurement and how they have fared against a "practical" gold standard.
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Semin Cardiothorac Vasc Anesth · Dec 2010
Review Case ReportsThe management of antiplatelet therapy in patients with coronary stents undergoing noncardiac surgery.
Whereas the development of coronary stents has been a major breakthrough in the treatment of coronary artery disease, stent thrombosis, associated with myocardial infarction and death, has introduced a new challenge in the care of patients with coronary stents undergoing noncardiac surgery. This review presents the authors' recommendations regarding the optimal management of such patients. ⋯ On the other hand, managing a patient undergoing non-elective surgery is more difficult and necessitates a case-by-case assessment of bleeding risk versus thrombotic risk based on patient comorbidities, type of stents present, details of the coronary intervention, and type of surgical procedure. Patients with a risk of bleeding that outweighs the risk of stent thrombosis should discontinue at least clopidogrel, whereas all other patients should continue dual antiplatelet therapy throughout the perioperative period.
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Semin Cardiothorac Vasc Anesth · Dec 2010
The efficacy of post-cardiopulmonary bypass dosing of vancomycin in cardiac surgery.
Objective. Vancomycin is administered widely to patients undergoing cardiac surgery as prophylaxis against resistant Gram-positive sternal wound and venous donor site infections. The purpose of this study was to determine the efficacy of a standardized prebypass and postbypass dosing regimen of vancomycin by assessing plasma concentrations in the immediate postoperative period and postoperative surgical site infections (SSIs). ⋯ Conclusion. Vancomycin concentrations in the serum were greater than the minimum inhibitory concentration for most staphylococci ranging from 4 to 19.3 µg/mL producing acceptable therapeutic serum concentrations and low rate of infectious complications. Thus postbypass dosing is acceptable in vancomycin cardiac surgical prophylaxis.
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Semin Cardiothorac Vasc Anesth · Dec 2010
Dynamics of extravascular pulmonary water and intracranial pressure in patients with ischemic stroke.
The objective of the present study was to examine the relationship among extravascular pulmonary water, intracranial and cerebral perfusion pressure, hemodynamic parameters (eg, cardiac index, system vascular resistance index), and brain stem function during acute ischemic stroke. The subjects were 17 comatose patients with ischemic stroke who were admitted to an intensive care unit. The results revealed an elevation in extravascular lung water in the absence of cardiac dysfunction. ⋯ There was a correlation between auditory-evoked potential parameters and extravascular lung water during the study period. The correlation between auditory-evoked potentials and extravascular lung water may imply that ischemic brainstem injury plays a significant role in the development of increased pulmonary capillary permeability and the elevation of extravascular lung water. Brain stem injury is a cause of noncardiogenic lung edema in comatose patients following acute ischemic stroke.
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Semin Cardiothorac Vasc Anesth · Dec 2010
Diagnosis of acute respiratory distress syndrome in nosocomial pneumonia.
Acute respiratory distress syndrome (ARDS) complicates nosocomial pneumonias (NPn) in 12% to 33% of patients with associated increases in mortality of up to 80%. A timely diagnosis of ARDS with NPn is, however, problematic. The aim of this investigation was to improve the diagnosis and treatment of the early stages of ARDS with NPn. ⋯ Elevation of extravascular lung water index along with other ARDS diagnostic criteria (oxygenation index, central hemodynamic indices) was predictive of early stage of ARDS in patients with NPn. The standard diagnostic criteria for ARDS, including the Murray score, oxygenation index, and radiographic data only predicted the later stages of ARDS in NPn. Early diagnosis of ARDS with concomitant NPn in the current study was associated with improved treatment results with decreased duration of artificial ventilation and intensive care unit stay.