Size distribution of embolic material produced at aortic cross-clamp manipulation.
OBJECTIVE
The association between aortic atherosclerosis and neurological damage during cardiac surgery is well recognized. The purpose was here to analyze the size distribution of particles produced at cross-clamp manipulation of the ascending aorta.


METHODS
A human cadaveric aortic perfusion model of retrograde design was applied (n=27). With this model, washout samples were collected from the pressurized ascending aorta during cross clamp manipulation. Before the experiment, the aorta was flushed to remove debris and with a baseline sample collected. The cross-clamp was opened to collect ten repeated aliquots with dislodged particles. Collected washout samples were evaluated by digital image analysis and microscopy.


RESULTS
Cross-clamping produced a significant output of particles, which was seen for size intervals of 1 mm and smaller (p=0.002 to p=0.022). In all size intervals the particle output correlated with the degree of overall aortic calcification (p=0.002 to p=0.025). The model generated substantially more small-size particles than large debris (p<0.010).


CONCLUSIONS
Aortic clamping was here verified to dislodge aortic debris which correlated with the degree of observed calcification. Macroscopic particles were few. In contrast, cross-clamping produced substantial numbers of small-size particles. These findings emphasize microembolic risks associated with cross-clamping of atherosclerotic vessels.
Department of Surgical and Perioperative Science, Section for Hand and Plastic Surgery, Umeå University Hospital, Umeå, Sweden.
Patrik
P
Boivie
Magnus
M
Hedberg
Karl Gunnar
KG
Engström
D000368:Aged; D001011:Aorta / Q000000981:diagnostic imaging / Q000473:pathology*; D001161:Arteriosclerosis / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*; D001344:Autopsy; D001921:Brain / Q000098:blood supply; D002102:Cadaver; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000295:instrumentation; D003250:Constriction; D005260:Female; D006801:Humans; D008297:Male; D010477:Perfusion; D018709:Statistics, Nonparametric; D020521:Stroke / Q000209:etiology / Q000473:pathology; D013525:Surgical Instruments / Q000009:adverse effects; D013923:Thromboembolism / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D018608:Ultrasonography, Doppler