Liva Nova Inspire 6F  (integrated arterial filter)  

Elective  CABG patient with standard medical history & no known coagulation pathologies. Full systemic anticoagulation was achieved & confirmed pre-CPB with an ACT over 450 seconds.

Immediately following the onset of bypass, the arterial filter was observed to have turbulent flow & higher than expected RPM's for the generated flows. The blood flow in the filter appeared to be turbulent and there was a gelatinous like appearance in the arterial line filter.

Visually all looked fine and arterial blood looked oxygenated. ACT, arterial & venous blood gases were sent immediately & indicated that there no issues with oxygenation  & CO2 removal.

There was no signs of this material elsewhere within the circuit. Arterial line pressures were also noted not to be higher than expected. The decision was taken not to replace the oxygenator and continue with CPB as there was no clinical indication for changing the oxygenator.

ACT's &  blood gases were repeated frequently throughout the case with no signs of  impairment of function. Towards the end of the bypass run the turbulent flow appeared to resolve & the RPM's also decreased. The oxygenator was  flushed through at the end of the case & there was significant residue  biological in nature in the filter.  

A total of 11 oxygenators were observed to have this occurrence. It is standard practice to shine a light directly on the oxygenator during CPB and to flush through the circuit to a cell saver.

No patients had a history of Covid 19 infection. In 2 of the cases coagulation screens were sent to our in hospital haematology lab, specifically D Dimer, Fibrinogen, APTT, PT, INR & PLT’s but no unusual results were noted.

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