Microemboli in our bypass circuits: a contemporary audit.

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Medical Device Technology

Background:

• Cardiopulmonary bypass (CPB) circuits can introduce arterial microemboli.
• Clinical studies on CPB-related microemboli are limited, with most research being in vitro.
• Identifying microemboli sources is crucial for improving CPB safety and patient outcomes.

Purpose of the Study:

• To prospectively audit microemboli generation within a contemporary CPB circuit using the Emboli Detection and Classification (EDAC) system.
• To quantify emboli number and volume at different points in the CPB circuit.
• To identify the primary sources of microemboli during clinical CPB procedures.

Main Methods:

• A prospective clinical audit was conducted on standard CPB circuits in 12 patients.
• Three EDAC system probes were placed on the venous line, hard-shell venous reservoir (HSVR) outlet, and arterial line filter.
• Emboli counts and volumes were recorded at 30-second intervals, synchronized with the perfusion data management system.

Main Results:

• Microemboli counts were significantly higher downstream of the HSVR than the venous line.
• The arterial line filter significantly reduced both emboli count and volume.
• Microemboli generation increased with the left ventricular vent in operation, with air entrainment from the venous line being a major source.

Conclusions:

• The EDAC system effectively quantifies microemboli in CPB circuits.
• Left ventricular venting and venous line air entrainment are significant sources of microemboli.
• Continuous auditing and potential component redesign can enhance CPB safety and improve patient outcomes.