Anesthesia and analgesia
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Anesthesia and analgesia · Aug 1995
Quantification of thrombelastographic changes after blood component transfusion in patients with liver disease in the intensive care unit.
Thrombelastography (TEG) can be used to monitor hemostasis and guide transfusion therapy during orthotopic liver transplantation. However, data are limited regarding the type and quantity of blood components necessary for TEG-guided blood component transfusion in coagulopathic critically ill patients with liver disease. We evaluated changes in four thrombelastogram variables (reaction time, thrombin constant time, alpha angle, and maximum amplitude) in whole blood samples after 74 separate blood component transfusions in 60 critically ill patients with a coagulopathy and liver disease. ⋯ Each unit of platelets decreased the reaction and thrombin constant time by 0.43 (P < 0.05) and 0.82 (P < 0.005) min, respectively, increased the alpha angle by 1.5 degrees (P < 0.005), and the maximum amplitude by 1.4 mm (P < 0.005). In patients who received multiple blood components, cryoprecipitate decreased the thrombin constant time by 0.56 min/U (P < 0.05), and each unit of platelets decreased the thrombin constant time by 0.39 min (P < 0.005), and increased the alpha angle and maximum amplitude by 0.63 degrees (P < 0.05) and 0.99 mm (P < 0.005), respectively. We conclude that platelet transfusions, alone or in combination with other blood components, are most effective for improving abnormal TEG variables in coagulopathic critically ill patients with liver disease.
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Anesthesia and analgesia · Aug 1995
The effects of nitrous oxide on left ventricular systolic and diastolic performance before and after cardiopulmonary bypass: evaluation by computer-assisted two-dimensional and Doppler echocardiography in patients undergoing coronary artery surgery.
We investigated the effects of nitrous oxide (N2O) on central hemodynamics and left ventricular systolic and diastolic function in 25 patients undergoing coronary artery bypass surgery. All patients were receiving beta-blockers and had good left ventricular function. Global and regional systolic left ventricular performance and diastolic function were determined by computer-assisted analysis of transesophageal echocardiographic (TEE) images, and mitral Doppler flow profiles, respectively. ⋯ N2O induced a significant change in regional wall motion after, but not before CPB, as assessed by the relationship between segmental area ejection fraction (SAEF) and GAEF. Analysis of the mitral flow profile indicated an increase in early diastolic relaxation in the pre-CPB period after introduction of N2O, that was absent in the post-CPB period. We conclude that N2O induces regional wall motion abnormalities and possibly diastolic dysfunction post-CPB.
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Anesthesia and analgesia · Aug 1995
Hemostatic factors and replacement of major blood loss with plasma-poor red cell concentrates.
The purpose of this study was to assess the change of platelet and fibrinogen concentrations and the change of activities of prothrombin and factors V and VII when major surgical blood loss was replaced with plasma-poor red cell concentrates (RCCs) and colloid plasma substitutes. Sixty patients were studied. The average blood loss was 65% +/- 41% of the calculated blood volume (CBV). ⋯ The initial fibrinogen concentration was 3.7 +/- 1.1 g/L and the hemostatically significant level of 1.0 g/L was already reached at 142% (117%-169%) blood loss (r2 = 0.90). Activities of prothrombin and coagulation factors V and VII reached their critical levels at 201% (160%-244%), 229% (167%-300%), and 236% (198%-277%) blood loss, respectively. We conclude that deficiency of fibrinogen develops earlier than any other hemostatic abnormality when plasma-poor RCCs are used for the replacement of major blood loss.