No abstract

Cardiac output (CO) determination using transesophageal Doppler is based on the measurement of descending aortic blood flow. Because cerebral blood flow is dependent on PaCO2, an increase in PaCO2 would result in an increase of CO because of the increase in cerebral blood flow and vice versa. We enrolled 30 patients undergoing off-pump coronary artery graft surgery in the study. The CO was determined by both transesophageal Doppler and thermodilution while PaCO2 was maintained at either 30 mmHg or 40 mmHg in random order. The CO by thermodilution was significantly higher at PaCO2 of 40 mmHg (4.17 +/- 0.94 L/min) than at 30 mmHg (3.78 +/- 0.85 L/min). On the other hand, there were no significant differences in CO by transesophageal Doppler: 3.85 +/- 0.76 L/min at PaCO2 of 40 mmHg and 3.77 +/- 0.74 at 30 mmHg. Bland-Altman analysis yielded bias and precision of -0.32 and 0.49 L/min at PaCO2 of 40 mmHg, and -0.01 and 0.34 L/min at 30 mmHg. These results indicate that both methods of CO measurement are in agreement at 30 mmHg of PaCO2, but the thermodilution method provides higher values at 40 mmHg of PaCO2.

No abstract

We report an emergent case of cardiac tamponade due to rupture of the left ventricle. Preload and intracardiac volume were decreased by percutaneous cardiopulmonary support (PCPS), which led to the collapse of the cardiac chamber. The collapsed cardiac chamber made it difficult to diagnose cardiac abnormalities by preoperative transthoracic echocardiography (TTE). On loading fluid infusion and transfusion as volume load to improve the hemodynamic status, transesophageal echocardiography (TEE) revealed several leakages in the left ventricular myocardium. Continuous careful observation on TEE led us to a confident diagnosis of left ventricular rupture. The diagnosis by TEE also led to the employment of the appropriate procedure. TEE is useful for detecting an abnormality due to the location of the cardiac chamber and echocardiographic probe. We also note that continuous careful observation led to the employment of the appropriate procedure.