Effect of Preoperative Omitting Angiotensin-converting Enzyme Inhibitor on Hemodynamics in Patients Undergoing Off Pump Coronary Artery Bypass Surgery / 대한마취과학회지

BACKGROUND: Angiotensin-converting enzyme inhibitors (ACE-I) have been widely used for cardiac patients. This study investigated the effect of omitting ACE-I medication on hemodynamics during induction of anaesthesia and operation in patients chronically treated with ACE-I undergoing off pump coronary artery bypass graft surgery (OPCAB). METHODS: Sixty patients scheduled for OPCAB were included in this study. Patients not treated with ACE-I were included in control group (Group 1, n = 20). And then, patients treated with ACE-I more than 4 weeks were randomly divided into two groups: continuing group including patients who continued ACE-I medication until the morning of surgery (Group 2, n = 20) and discontinuing group including patients who discontinued ACE-I one day before the surgery (Group 3, n = 20). Norepinephrine (8microgram/ml) was infused when systolic blood pressure decreased below 90 mmHg during induction and operation. Amount of norepinephrine infused and hemodynamic data were recorded. RESULTS: Significantly larger amount of norepinephrine was infused in Group 2 than in other two groups during obtuse marginal artery anastomosis. Total amount of norepinephrine infused during the all coronary anatsomosis was significantly larger in Group 2 than those values in other two groups. CONCLUSIONS: Continuing ACE-I treatment until the morning of surgery significantly increased the use of norepinephrine during the anastomosis. In contrast, there was no significant difference in the use of norepinephrine between Group 1 and Group 3. Discontinuing ACE-I before the surgery may helpful to maintain hemodynamics stable during coronary anastomosis in OPCAB.

Heparin Resistance during Cardiopulmonary Bypass in Infective Endocarditis Patients: A case report / 대한마취과학회지

Appropriate anticoagulation is essential for safe cardiopulmonary bypass (CPB). Two patients with infective endocarditis were scheduled for valve replacement. After an intravenous heparin injection for the CPB, the increases in the activated clotting time (ACT) in both patients were less than expected. Subsequent additional heparin administration failed to maintain a sufficient ACT for the CPB, and antithrombin III (AT III) tests during the CPB revealed low activities in both patients. Heparin resistance, due to consumption of circulating AT III as a result of infective endocarditis or prior heparinization, was postulated. While fresh frozen plasma (FFP) could not be timely administered in the first patient, ACT was successfully prolonged after the administration of FFP in the second. It is strongly suggested that adequate management of heparin resistance should be prepared for patients with infective endocarditis who require CPB.

Heparin Resistance during Cardiopulmonary Bypass in Infective Endocarditis Patients: A case report / 대한마취과학회지

Appropriate anticoagulation is essential for safe cardiopulmonary bypass (CPB). Two patients with infective endocarditis were scheduled for valve replacement. After an intravenous heparin injection for the CPB, the increases in the activated clotting time (ACT) in both patients were less than expected. Subsequent additional heparin administration failed to maintain a sufficient ACT for the CPB, and antithrombin III (AT III) tests during the CPB revealed low activities in both patients. Heparin resistance, due to consumption of circulating AT III as a result of infective endocarditis or prior heparinization, was postulated. While fresh frozen plasma (FFP) could not be timely administered in the first patient, ACT was successfully prolonged after the administration of FFP in the second. It is strongly suggested that adequate management of heparin resistance should be prepared for patients with infective endocarditis who require CPB.

The Effect of Preoperative Pulmonary Arterial Pressure and Right Ventricular Function on the Changes in Right Ventricular Function after Mitral Valve Replacement / 대한마취과학회지

BACKGROUND: In patients with mitral valvular disease with pulmonary hypertension (PHT) accompanying right ventricular (RV) dysfunction, mitral valve replacement (MVR) improves RV function and other hemodynamic variables in long term follow-up. However, there are controversies in improvement of RV function in the immediate postoperative period. We compared the RV function immediately after a MVR with a pulmonary artery catheter (PAC) between patients with normal and decreased RV function with PHT preoperatively. METHODS: Twenty nine patients undergoing a MVR were included in the study. The patients (n = 14) with mean pulmonary arterial pressure (PAP) < or = 25 mmHg were assigned to group I and the patients (n = 15) with mean PAP 25 mmHg were assigned to group II. A PAC with rapid response-thermistors which enables us to determine right ventricular ejection fraction (RVEF) was inserted in all patients and hemodynamic variables were measured before and after cardiopulmonary bypass (CPB). RESULTS: After CPB, PAP, pulmonary vascular resistance index (PVRI), and RV end-diastolc volume (RVEDV) were significantly decreased and RVEF was significantly increased in group II compared with group I in which no hemodynamic variables were changed. CONCLUSIONS: A MVR decreased RV afterload and increased RV function more significantly in patients with preoperative PHT accompanying RV dysfunction than in patients with normal PAP preoperatively.