Hypothesis: Portal flow pulsatility detected by Doppler ultrasound during cardiac surgery is an echographic marker of cardiogenic portal hypertension from right ventricular failure and is associated with adverse clinical outcomes.
Background: Peri-operative right ventricular failure is associated with a high mortality rate. In this context, organ perfusion is hampered by both the reduction of cardiac output and venous congestion from the elevation of central venous pressure. The clinician's objective is to appreciate the hemodynamic impact on end-organs in an effort to adjust the therapy accordingly since the ultimate goal is to optimize their perfusion. Based on this rationale, organ specific blood flow assessment using Doppler ultrasound could be used to personalize management. In order to non-invasively assess the presence of cardiogenic portal hypertension, Doppler ultrasound can be used to detect portal flow pulsatility, an abnormal variation in the velocity of blood flow within the main portal vein. In two single-center cohort studies, the presence of portal flow pulsatility after cardiac surgery was independently associated with post-operative complications such as major bleeding, acute kidney injury (AKI) and delirium as well as increased length of intensive care unit (ICU) stay.
Specific Objectives: This multi-center cohort study aim to determine whether the association between portal flow pulsatility and organ dysfunction seen in previous studies is present across multiple cardiac surgery centers.
