Pulsatile II study.

Rationale:

Non-pulsatile cardiopulmonary bypass (CPB) during cardiac surgery is associated with postoperative disturbances in microcirculatory perfusion, which are prevented by reinstatement of pulsatile flow. Moreover, impaired microcirculatory perfusion after non-pulsatile flow correlates with the presence of prothrombogenic markers. The question arises whether prothrombogenic alterations are indeed related to disturbances in microcirculatory perfusion, and how this relation is affected by non-pulsatile and pulsatile CPB. Furthermore, it is unknown whether the relation of a prothrombogenic profile with microcirculatory perfusion involves distinct alterations in endothelial function.



Objectives:

We aim to investigate whether pulsatile flow in patients subjected to CPB preserves postoperative microcirculatory perfusion by prevention of a prothrombogenic profile and endothelial activation as are both present under non-pulsatile flow conditions.



Study design:

Single-center prospective, randomized study in the VUmc.



Study population:

Patients undergoing elective coronary bypass graft surgery (CABG; n = 48). Patients will be randomly assigned into two study groups:

1. Non-pulsatile flow: Continuous flow during CPB;

2. Pulsatile flow: Pulsatile flow during CPB.



Intervention:

The intervention consists of the application of one type of cardiopulmonary bypass (conventional or pulsatile CPB). All interventions are part of standard clinical care.



Main study parameters/endpoints:

Change in microcirculatory perfusion, sublingual erythrocyte velocity, capillary diameter and capillary density.

Pulsatile flow during cardiopulmonary bypass (CPB) results in preservation of microcirculatory function in the early postoperative period as compared to non-pulsatile CPB.

Measurements take place during the day of the operation and end within 4 hours after the operation.

Pulsatile cardiopulmonary bypass vs. non-pulsatile cardiopulmonary bypass.