Experimental Study Of The Effects Of Phenytoin Sodium On The Survival Of Random Pattern Skin Flaps

Random skin flaps are widely used in plastic surgical operations, of which the long-broad ratio is limited at about 1.5:1, for larger ones may cause the skin flap necrosis. Therefore the application of skin flap is restricted to a certain extent.Many kinds of growth factors appear to have the ability of increasing the survival of skin flaps. And there shows synergetic effects among different kinds of growth factors during the process, which indicates that the application of the combination of different growth factors maybe more effective than a single one. However the cost rises at the same time. In fact the increase of the concentration of growth factors can not only be reached from the administration of exogenous growth factors, but also the promotion of the synthesis and releasing of endogenous ones. It is well known that the macrophage releases numerous biological active factors including growth factors during the healing process of wound, which play an important role in the regulation of the process. Phenytoin is a definite macrophage activator and proved effective in promoting the healing of wound. Besides activating macrophages, the mechanism involves decreasing the quantity and restraining the activity of neutrophil, stabilization of the membrane, anti-peroxidation of the lipids, depressing the synthesis of Prostaglandin, decreasing the synthesis and releasing of collagen enzyme, promoting the multiplication of fibroblast and synthesis of collagen, reducing the infection of wound and so on.In this experiment, the effect of phenytoin was explored using in random skin flaps through the topical administration under the flap after operation. Method: Twenty healthy SD mice, male and female both in half, with 200 to 250 gram in weight, were random distributed to the experimental group (Ph group) and the control one (NS group) after being laminated by sex. Random flap 2cm × 8cm in shape was made on the back of each mouse with the pedicel 0.5cm inferior to the inferior angular of the scapular. NS and phenytoin were injected into the flap respectively after the operation. The comparison of two groups included the gross observation, laser doppler bloodperfusion volume (BPV), tissue section, and the living area of the flaps. Result: 1) the BPV at the b point (3 cm to the pedicel) in Ph group is significantly higher than NS group (P <0.05), while the difference of the BPV at a point was not significant. 2) The percentage of the surviving area of skin flap (SR=surviving area/total area of skin flap) shows significant difference at the 7th day and the 10th day between 2 groups. 3) In Ph group, the percentage of the parbiosis area of skin flap (IR=parbiosis area/total area of skin flap) appears less than the NS group (P <0.05) at the 7th day, while no significant different either in the 4th or in the 10th day. 4 The number of capillaries in skin flaps of Ph group was higher than the control's (P <0.05). Conclusion: 1) topical use of phenytoin may promote the surviving of the parbiosis tissue in random skin flaps, and further increase the SR. 2) this effect was relatively obvious in 3-7 days after the operation.Nowadays professional image management software are widely used in the area measuring of skin flaps in international academic communications, while manual counting are still frequently referred in domestic literatures. Usually professional software has multifarious functions, and not easy to master. If the parameters are not properly initialized, larger error may be caused. In this experiment, an area analysis software for skin flaps was developed with Delphi 6.0. Further evaluations were performed on the precision of area measuring. Method: accurately draw 3 simple graphics, triangle, rectangle and roundness in prescriptive size, and 3 different colors were used to separate each of them into 3 prescriptive area. Digital image of the graphics were obtained 10 times through both camera and scanner. Each time the area was measured for 3 times with the help of the developed software. Finally the value of graphic area from measuring and calculation was compared. Result: The value from measuring is very close to that from calculation. Conclusion: The software can accurately measure the area of flat graphics and can be used in experiments and clinic practice.