A prospective randomised comparison of cardiotomy suction and cell saver for recycling shed blood during cardiac surgery.

Objective: Post-operative neuropsychological complications correlate with intra-operative microemboli in the middle cerebral artery. When severe neurological complications follow cardiac surgery, diffuse cerebral fat emboli are present at autopsy. Recycling shed blood with cardiotomy suction is an important source of cerebral fat microemboli. A cell saver may reduce this.

Methods: Twenty patients were prospectively randomised to assess the amount of fat in blood salvaged from the pericardium and returned to the patient with either cell saver or cardiotomy suction. Blood samples were taken before and after filtration in the cardiotomy suction group or cell saver processing in the cell saver group. After centrifuging samples, fat content was graded on a scale of 0-3 by a blinded independent observer. Fat content was also quantified by weight.

Results: Compared with cardiotomy suction, cell saver removed significantly more fat from shed blood. Median fat grading after cell saver was 0 (0-1) compared with 1 (1-2) for cardiotomy suction (P=0.0001). Percentage reduction in fat weight achieved by cell saver or cardiotomy suction was 87% compared to 45% (P=0.007). There was no difference in the post-operative use of blood or blood products, haemoglobin, or bleeding between the two groups.

Conclusion: Use of cell saver results in less fat being recycled during cardiopulmonary bypass.