Abstracts of Posters Presented at the International Anesthesia Research Society; 72nd Clinical and Scientific Congress; Orlando, FL; March 7-11, 1998: Cardiovascular Anesthesia
Introduction: Incidence of mediastinal re-exploration for excessive bleeding following cardiac surgery is 3 to 5%. It is associated with increased patient morbidity and cost. [1,2] We determined if coagulation tests could differentiate a surgical cause versus a coagulopathy in these patients.
Methods: With IRB approval, charts of 186 patients having mediastinal re-exploration following all types of cardiac surgery were reviewed. The surgery and bypass variables were also documented. Perioperative coagulation tests and the transfusion requirements for the initial surgery and the reoperative procedure were determined. A cardiac surgeon blinded to all other information determined the type of bleeding from the operative note. Patients were designated; as surgically bleeding (a bleeding vessel), coagulopathy (diffuse oozing) or as indeterminate. Data was expressed as median (range) and analyzed using the Kruskal-Wallis test. Statistical significance p <or=to 0.05
Results: There were no differences in demographic values or bypass duration between groups. There also was no difference in laboratory coagulation test values at any time point (Table 1). There also was no difference in transfusion requirements.
Discussion: Spiess et al. found that TEG monitoring reduced the incidence of mediastinal re-exploration for excessive bleeding.  We found that coagulation tests were not able to differentiate patients with a surgical source for bleeding from coagulopathy. The excessive bleeding may induce abnormal coagulation tests that makes it difficult to determine the etiology of bleeding in these patients.
1. Ann Thorac Surg 1990, 49:771-4.
2. J. Thorac Cardiovasc Surg, 1996, 111:1037-46.
3. J Cardiothor Vasc Anesth 1995, 9:168-73