Human albumin : cardiac surgery
Human albumin : advantages in cardiac surgery
In surgical patients , fluid overload , as caused by crystalloids , has been demonstrated to be an independent risk factor for morbidity and mortality . The benefits of the use of human albumin are here discussed
Alexey Schramko MD Department of Anaesthesiology and Intensive Care Medicine , Helsinki University Hospital , Finland alexey . schramko @ hus . fl
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During cardiac surgery , large fluid transfers , priming of cardiopulmonary bypass ( CPB ) circuit and blood and blood products transfusions , as well as long surgery time , lead almost always to fluid overload . Despite the large amount of fluids administered , patients who have had CPB often have blood volume deficit because of fluid shift from intra- to extravascular space due to systemic inflammatory response and damage of endothelial glycocalix . 1 The fluid ' leakage ' after cardiac surgery lasts for between several hours and several days . 2 Conversely , haemodynamics after cardiac surgery is often affected . The phenomenon of myocardial stunning is described widely and , in the early postoperative period , a significant number of patients need inotropic support and / or vasopressors because of the reversible acute heart failure . Additionally , the majority of patients postoperatively need more intravascular volume for cardiac output optimisation .
Coagulation disturbances CPB impairs blood coagulation and , in some cases , renal function . There are several mechanisms of coagulation disturbances during CPB . The contact pathway is triggered when factor XII , prekallikrein and high molecular weight kininogen interface with nonbiological surfaces of the CPB circuit . 3 The extrinsic coagulation pathway is triggered when
" Albumin solution provides good haemodynamic effect which lasts several hours without any clinically significant side-effects "
factor VIIa complexes with tissue factor being expressed on leucocytes , platelets or exposed subendothelium within the vessel wall . Therefore , thrombin generation increases strongly . 4 On the other hand , CPB initiation leads to the decrease of coagulation factors ( partially , due to haemodilution ) and increases the fibrinolytic activity . 5 The incidence of severe bleeding in cardiac surgery exceeds 10 %, and approximately 5 – 7 % of patients experience blood loss in excess of 2L within the initial 24h postoperatively . 6
After CPB , patients are predisposed to different complications , and the discovery of optimal conditions is challenging . The optimal volume resuscitation after CPB should be performed using small amounts of fluid , which stay at least several hours intravascularly without undesirable side effects .
Different solutions , both crystalloids and colloids , have been used for volume replacement after cardiac surgery . A Cochrane systematic review did not find any difference in major outcomes when colloids have been compared to crystalloids . 7 Crystalloids do not have significant side-effects apart from haemodilution , but their volume effect is low ( about 20 %) and they stay in the intravascular space for a very short time , www . hospitalpharmacyeurope . com