Experimental study on the change of dynamic expression of t-PA and PAI-1 during early venous crisis after free perforator flap transplantation / 中华显微外科杂志

ABSTRACT

Objective To investigate the change of dynamic expression of t-PA and PAI-1 during early venous crisis after free perforator flap transplantation.Methods Thirty healthy New Zealand white rabbits weighed 2.5-3.0 kg were chosen and randomly divided into experimental group (n =15) and control group (n =15).Free transplantation of superficial epigastric artery perforator flap (SEAPF) was implemented in all rabbits firstly.Then the model of venous crisis was established by ligating the anastomosis vein in order to interrupt venous blood outflow in experimental group.The blood supply of all flaps was monitored by observing their color,swelling degree and the filling reaction of the capillaries after operation.Peripheral blood was drawn from femoral artery at different time point for measuring the concentration of t-PA and PAI-1 by Elisa.Partial flap tissue was harvested for pathological examination at corresponding time point.Data analysis was performed by using SPSS 17.0 statistical software.P ＜ 0.05 was considered statistically significant.Results One rabbit died of anesthesia,and the venous congestion was observed in 1 rabbit in control group.The models of free transplantation of SEAPF and venous crisis were established successfully in the remaining rabbits.No significant appearance change was observed within 1 h after the outflow vein being ligated,while typical appearance of venous crisis could be observed 2 hours after the outflow vein being ligated.Compared with the control group,the concentration of t-PA was lower,but the concentration of PAI-1 was higher in experimental group at 2 hours,4 hours,6 hours,8 hours after the outflow vein being ligated(P ＜ 0.05).However,there was no obvious differences between two groups at other time points (P ＞ 0.05).The pathological examination showed the red cells gradually got together and adhered to the venous wall,eventually the microcirculation had been blocked completely and theflap became necrosis after venous crisis being occurred.Conclusion t-PA and PAI-1 can't be used to diagnose early venous crisis of perforator flap transplantation.