The Experimental Study Of Relationship Between Expression Of NOS, CD34 And Flap Survival Area In Narrow Flap

Objective: To design different long and narrow aspect ratio of narrow pedicle flaps in pigs back, we measured the expression of NOS and CD34 in different time, observed the survival area of shin flaps. We tired to reveal the relationship between NOS,CD34 expression and the flap survival area, explored the narrow strip of flap survival mechanism.Methods: The five white domestic pigs were formed five narrow flaps on both sides of the back, which pedicle width length ratio were 2cm:4cm strip, five flap carried different areas of random skin flap, respectively 2cm×2cm, 3cm×3cm, 4cm×4cm, 5cm×5cm, 6cm×6cm, and in turn named A, B, C, D, E. Flaps and flaps spaced 4cm, the pedicle back were away from the midline 4cm. All flaps were randomly arranged. After the operation, we injected 10% of the fluorescent pigment sodium (25mg/kg) into pigs through the ear vein. 10 minutes later, we observed the range of flaps fluorescence staining and predicted flap survival area under the UV lamp. Surgery in the immediate postoperative, the 3rd, the 5th,the 7th,the 14th day, we cut 0.5cm×0.3cm full - thickness tissue from each flaps of the outer edge to carry out pathological examination, immunohis-tochemical staining and determined NOS, CD34 expression. After 14 days, we measured flap survival area, observed contents of NOS, CD34 in flaps healing process, comprehended their dynamic change, in order to reveal the relationship between expression of NOS, CD34 and flap survival rate.Results: Narrow pedicle flaps survived well, which broke out traditional restrictions on the narrow aspect ratio. For A, B, C group flaps, expression level of NOS, CD34 increased as the flap gradually increased, flaps completely survived(P<0.05); For D, E group flaps, expression level of NOS, CD34 no longer increased with the increase of skin flap area , while its expression were constant relatively, flap partial necrosis(P>0.05). Each group in the NOS, CD34 expression level gradually increased after operation, in which NOS got to peak in the 5th day, the 5th-7th days were maintained at a high level, and then gradually decreased; CD34 gradually increased after the operation, and got to peak in the 5th day, the 5th day to the 14th day had been maintained at high levels.Conclusions: 1.Aspect ratio is not the crucial factor which determine flaps survive or not, aspect ratio and survival area are not directly proportion relationship; within a certain aspect ratio, area increases, flaps survive well; When flaps reach a certain level, then increase flaps area, flap survival area reach to the maximum, the excess will be remote necrosis. 2.Within a certain range, with the flap area increase, flaps NOS,CD34 expression level gradually increase, flaps survive completely; more than a certain range, and increase flaps area, flaps NOS,CD34 expression will be permanent, some flap will necrosis; 3.The expression of NOS, CD34 in Random pattern flap and flap survival rate have obvious relevance.