Venous cannula occlusion during cardiopulmonary bypass recognized by ultrasonography of the internal jugular vein.

BACKGROUND: Occlusion or malposition of the venous cannula during cardiopulmonary bypass (CPB) increases central venous pressure (CVP). When high CVP is measured, we need to determine if it is actually high or if it is measured due to catheter occlusion or technical problems with the measurement. CASE PRESENTATION: We experienced a case of excessively high CVP due to malposition of the venous cannula during CPB. A 78-year-old woman underwent an aortic arch replacement for acute aortic dissection. During CPB, CVP increased up to 78 mmHg, and the time above 50 mmHg was 48 min. In this case, ultrasonography of the internal jugular vein (IJV) was useful to confirm high CVP. CONCLUSIONS: Ultrasonography is now a familiar diagnostic tool and can be used at any time. We should consider ultrasonography as the first choice for diagnosing the cause of high CVP during CPB.