Vacuum-Assisted Closure for Mediastinitis Caused by Methicillin-Resistant <i>Staphylococcus aureus </i>after Coronary Artery Bypass Grafting / 日本心臓血管外科学会雑誌

Mediastinitis caused by methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) is a severe complication after coronary artery bypass grafting (CABG). Vacuum-Assisted Closure (VAC) therapy is a technical innovation in wound care. The advantage of VAC is the application of negative pressure to sternal wounds. A 73-year-old man was admitted to our hospital because of operation for triple vessel disease including left main coronary artery lesion. Off-pump CABG was performed using the bilateral internal thoracic arteries and right gastroepiploic artery. The postoperative course was uneventful. However, purulent discharge from a median sternostomy wound appeared on the 11th postoperative day. MRSA was identified by the culture of the wound exudate. On operation, the necrotic tissue was removed, and continuous irrigation and drainage were performed. Conventional technique was not effective. VAC therapy was applied on the 35th postoperative day. During VAC therapy, the wound became smaller and granulation tissue proliferated. VAC therapy was discontinued on the 208th postoperative day. Finally, the wound was naturally closed. He was discharged in good condition on the 213th postoperative day. VAC therapy was an effective treatment for MRSA mediastinitis after cardiac surgery.

An Operative Case of Chronic Traumatic Thoracic Aortic Aneurysm, 19 Years after a Traffic Accident / 日本心臓血管外科学会雑誌

A chronic traumatic thoracic aortic aneurysm, 19 years after a traffic accident was successfully treated. A 34-year-old man was admitted because of chest discomfort. An upper GI examination was performed and an esophageal submembranous tumor was suspected. However, a chest CT examination showed a thoracic descending aortic aneurysm, the maximum size of which was 7.5cm×5.5cm. The final diagnosis was chronic traumatic thoracic aortic aneurysm. Generally most cases of chronic traumatic thoracic aortic aneurysm have no symptoms for a long time after an accident. However, some have reported that the development of an aneurysm is due to not receiving treatment. We performed graft replacement using the temporary bypass method because it was an easy technique and required less heparinization. Chronic thoracic aortic aneurysms have lower risk of bleeding during the operation than acute cases. For chronic cases which have stable hemodynamics, adjunctive methods (e. g., partial extracorporeal bypass, left ventricular bypass and temporary bypass) may facilitate a safe operation.

Appropriate Protamine Administration to Neutralize Heparin after Cardiopulmonary Bypass Using the Hepcon/HMS / 日本心臓血管外科学会雑誌

We reevaluated our heparin and protamine administration protocol during and after cardiopulmonary bypass (CPB). In 12 patients who underwent cardiac surgery using a heparin-coated circuit under mild hypothermia, heparin concentration was measured with the Hepcon^®/HMS. Before initiating CPB, 1.5mg/kg of heparin was given to maintain the activated clotting time (ACT) at more than 400sec. Patients were divided into two groups. In group I (<i>n</i>=6), heparin was neutralized with an empirical dose of protamine (1.5mg protamine/mg initial heparin). In group II (<i>n</i>=6), the protamine dose was determined by the residual heparin concentration, measured with the Hepcon^®. Patients in group II received a lower dosage of protamine than group I (1.7±0.0 vs. 3.6±0.4mg/kg, <i>p</i><0.001). There were no significant differences in the intraoperative bleeding, postoperative bleeding and activated clotting time between the groups. By determining the appropriate protamine dosage, this heparin analysis system may be useful in managing CPB.