Blood-air interface during cardiopulmonary bypass

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Anesthesiology

Background:

• Cardiopulmonary bypass (CPB) is essential for cardiac surgery but can activate the systemic inflammatory response.
• Open and closed perfusion management strategies exist, each with potential benefits and drawbacks regarding blood activation and patient outcomes.

Purpose of the Study:

• To compare systemic blood activation, blood loss, and donor blood requirements between open and closed perfusion management during CPB.
• To evaluate the impact of different venous reservoir systems on inflammatory markers and coagulation activation.

Main Methods:

• A prospective study of 30 patients undergoing coronary artery bypass grafting.
• Patients were divided into two groups: 15 using an open venous reservoir (hard shell) and 15 using a totally closed venous reservoir (collapsible, modified vent, cell saver).
• Systemic blood activation markers (FXIIa, C3a, Interleukin-6, Elastase) and blood loss were measured preoperatively, postoperatively, and 24 hours postoperatively.

Main Results:

• No statistically significant differences were observed in FXIIa, C3a levels, blood loss, or donor blood requirements between the open and closed groups.
• Interleukin-6 and Elastase levels indicated a trend towards a lesser inflammatory reaction in the closed venous reservoir group.
• Patient demographics and perfusion times were comparable between the two groups.

Conclusions:

• Optimized air management in perfusion systems did not significantly reduce inflammatory response or influence the coagulation system in this cohort.
• While trends suggest potential benefits for closed systems in reducing inflammation, further research with larger sample sizes is warranted.
• Current perfusion management modifications may not be sufficient to mitigate systemic blood activation during cardiopulmonary bypass.