Microsoft word - oxidized cellulose as a cause of acute ischemic event after coronary revascularization1.docx

Oxidized cellulose as the cause of an acute ischemic event after coronary Jose Rubio Alvarez , Juan Sierra Quiroga , Jose Martinez Cereijo , Laura Reija Lopez Cardiovascular Department . Universitary Hospital of Santiago de Compostela . Spain . Publicado : Interactive Cardio Vascular Thoracic Surgery 2010 ; 11 : 488. Absorbable topical hemostatic agents are commonly used in cardiac surgery . In this study we report an unusual case of an acute ischemic event after coronary revascularization produced by interaction between oxidized cellulose and epsilon aminocaproic acid . An in vitro study was also performed to test the interaction between oxidized cellulose and epsilon aminocaproic acid . Key Words : Ischemic event , Oxidized cellulose , Coronary revascularization . Postoperative bleeding is one of the most frequent complications in cardiac surgery [1]. Bleeding necessitating reoperation occurs in 4 % to 7 % of patients after CPB and 50% to 70% of them will not have a surgical bleeding source . Fibrinolysis has been reported to be the cause of 25% to 45% of postoperative bleeding [ 2 ] and the use of both systemic antifibrinolytic agents and absorbable topical hemostatic agents is commonplace during cardiac surgical procedures [3,4] . The adverse effects after systemic use of antifibrinolytic agents is one of the reasons these agents are applied topically [5 ] . Until recently there were no reports in the literature describing ischemic events produced by the interaction of oxidized cellulose with topical epsilon We report the case of a 79-year-old man with unstable angina who was referred to our departement for surgical revascularization . The coronariography showed significant left main coronary artery and right coronary artery lesions . The patient had insulin-dependent diabetes and chronic obstructive lung disease . A routine coronary revascularization with left internal Mammary artery to Anterior Descending and saphenous veins to Right Coronary artery and 1st Marginal ( OM ) was performed under cardiopulmonary bypass . Oxidized cellulose was placed around the OM anastomotic suture because of a continous oozing and before proceeding with the sternal closure the pericardial cavity was washed with 100 ml of saline solution containing 8 g of EACA . During the sternal closure , a severe hypotension with ST elevation in the posterior leads and a ventricular fibrillation occurred . Defibrillation was performed and because the ST modifications remained , the oxidized cellulose which had formed a solid and rigid shape , was removed . The ST elevation inmediately disappeared . The subsequent intraoperative and postoperative course was uneventful An in vitro study was performed using three different doses of EACA ( 4 , 8 , 12 Gr ) . When the oxidized cellulose contacted the saline solution containing EACA , it rolled up immediately and it turned into a rigid shape ( Fig 1 ) . A segment of the saphenous vein with a hemostatic clip at the distal end was gently distended and a piece of oxidized cellulose was placed around the vein . Then we placed the vein in a saline solution containing EACA and when the oxidized cellulose turned into the rigid shape , Figure 1 .- The rigid shape that the oxidized cellulose takes after contac with EACA . We show a control , unexposed piece for comparison . Figure 2 .- Saphenous vein constriction caused by oxidized cellulose ( in vitro study ) . Postoperative bleeding requiring re-exploration occurs in 4% to 7% of patients after cardiopulmonar bypass and an identifiable surgical bleeding source cannot be found in more than 50% of these occurrances [ 1 ]. Brown and colleagues [ 3 ] conducted a meta-analysis to compare the effectiveness of aprotinin , EACA and tranexamic acid with placebo . They concluded that all antifibrinolytic agents were effective in reducing blood loss and transfusion . However intravenous antifibrinolytic agents administration have been associated with an increased risk of thromboembolic events and early graft closure after coronary revascularization [6] and new data have emerged regarding an increase in adverse outcomes associated with the systemic use of antifibrinolytic agents and most of these effects are avoided by topical application [5,7] . The fact that after topical use of Tranexamic acid and Aprotinin , they could not be detected in any of the blood samples [8] strongly suggest that their effects were due to topical action . On the other hand topical hemostatic agents are efficacious in reducing blood loss during surgery [ 4 ] and they can be temporarily administered to avoid sternal bleeding complications [ 9 ] . Canver [ 10 ] reported a draping technique to prevent coronary bypass graft kinking and sutureline oozing using oxidized regenerated Oxidation is the only process that renders cellulose bioabsorbable in man , however a major problem with oxidation is the difficulty of producing materials that are homogeneous in chemical and physical properties . Oxidized cellulose is a fabric material that is obtained by the oxidation of cotton gauze or other cellulose fabric using nitrous oxide to achieve oxidation . The oxidation reaction makes the material soluble at physiological conditions . Oxidized regenerated cellulose similar to oxidized cellulose , but natural cellulose is first dissolved and then extruded as a continuous fiber . The fabric made from the fiber is very uniform in chemical composition and its oxidation therefore is more closely regulated . This uniform oxidation results in less variation in stability and absorbability of the material . In our in vitro study , when the oxidized regenerated cellulose contacted EACA , it turned a yellowish brown color and became gelatinous . However when the oxidized cellulose contacted EACA , it rolled up immediately and turned into a rigid shape . Within a few days , most of the fibrous structure is gone . The information presented in this report is the first case of adverse interactions between oxidized cellulose and topical epsilon aminocaproic acid and we do not 1.- Kajani MK , Waxman HS . Hematologic problems after open heart surgery . In : Kotler MN , Alfieri A editors . Cardiac and noncardiac complications of open heart surgery: Prevention , diagnosis and treatment .New York: Futura Publishing Company, 2.- Kevy SV , Glickman RM , Bernhard WF , Diamond LK , Grass RE . The pathogenesis and control of the hemorrhagic defect in open heart surgery . Surg 3.- Brown JR , Birkmeyer NJ , O´Connor GT . Meta-analysis comparing the effectiveness and adverse outcomes of antifibrinolytic agents in cardiac surgery . Circulation 2007 ; 115 (22) : 2801 - 2813 . 4.- Krishnan S , Conner TM , Leslie R , Stemkowski S , Shander A . Choice of hemostatic agent and hospital length of stay in cardiovascular surgery . Semin Cardiothorac Vasc Anesth . 2009 ; 13 (4) : 225 - 230 . 5.- Baric D , Biocina B , Unic D , Sutlic Z , Rudez I , Basic Vrca V , Brkic K , Ivkovic M Topical use of antifibrinolytic agents reduces postoperative bleeding : a double-blind , prospective , randomized study . Eur J Cardiothorac Surg 2007 ; 31 : 366-371 . 6.- Ovrum E, Holen EA , Abdelnoor M , Oystese R , Ringdal ML . Tranexamic acid ( Cyklokapron ) is not necessary to reduce blood loss after coronary artery bypass operations . J Thorac Cardiovasc Surg 1993 ; 105 : 78 - 83 . 7.- Mangano DT , Tudor IC , Dietzel C . The risk associated with aprotinin in cardiac surgery . N Engl J Med 2006 ; 354 : 353 - 365 . 8.- De Bonis M , Cavaliere F , Alessandrini F , Lapenna E , Santarelli F , Moscato U , Schiavello R , Possati GF . Topical use of Tranexamic acid in coronary artery bypass operations : A double-blind , prospective , randomized , placebo-controlled study . J Thorac Cardiovasc Surg 2000 ; 119 : 575 - 580 . 9.- Mair H , Kaczmarek I , Oberhoffer M , Groetzner J , Daebritz S , Reichart B . Surgicel Nu-Knit hemostat for bleeding control of fragile sternum . J Thorac Cardiovasc 10.- Canver CC . A draping technique for prevention of coronary bypass graft kinking and suture - line oozing . J Card Surg 1996 ; 11(6) : 408 - 410 .

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