Summary
Plasma concentrations of fibronectin, albumin, total protein and IgM were measured
in 14 male patients undergoing aorto-coronary bypass operations. Fibronectin and IgM
concentrations feil to 55% of the preoperative values 5 minutes after start of the
extracorporeal circulation, and the same percentages were encountered 5 minutes after
the termination of bypass. The concentrations had recovered to 75% of the preoperative
values by the end of the operation. The plasma concentration of albumin was 68 ± 9%
of the preoperative value after 5 minutes of bypass, 66 ± 7 % at the end of bypass,
and 83 ± 9% of the end of operation (signifi-cantly different from fibronectin and
IgM, p < 0.05; Wilcoxon's test for paired differences). No correlation was found between
the duration of extracorporeal circulation and the post-bypass concentrations of any
protein (Kendali correlation). It is concluded that the fall of fibronectin concentrations
during cardiopulmonary bypass can be sufficiently explained by dilution, and that
a specific consumption of fibronectin does not occur. The less marked decreases of
albumin and total protein were probably due to infusion of plasma-protein solution,
which is poor in fibronectin and IgM.
Key words
Fibronectin - IgM - Extracorporeal circulation - Aorto-coronary bypass
