Aim: To study the change of blood flow velocity and skin temperature of the random pattern flap during the process of healing under the regulation of nerve growth factor(NGF). Methods: The animal model of the random pattern flap in rat back was adopted. NGF 66. 7 μg were locally injected once only in experimental group after operation with auto-control. The changes of blood flow velocity and skin temperature of random pattern flap were observed continuously by using laser and fiber optic techniques. Results: The blood flow velocities of the end, middle and pedicle of the random pattern flap in the experimental group[ (0.94 ± 0.32), (1.09 ± 0.53) and (1.11 ± 0.94) mm/s] were obviously faster than those in the control group[ (0.85 ± 0.29), (0.96 ± 0.31) and (1.01 ± 0.34) mm/s] 1 day after operation(t = 2.39, 1.98 and 2.13, P < 0.05). The blood flow velocities of the middle and pedicle of random flap in the experimental group [ (0.99 ± 0.42), (0.96 ± 0.25) mm/s] were very significantly faster than those in the control group[ (0.83 ± 0.37), (0.80 ± 0.41) mm/s] 5 days after the operation(t = 2.6 and 3.31, P < 0.01). The skin temperatures of the middle and end parts were (30.91 ± 1.13), (30.15 ± 0.92) °C 1 day after the operation and that of the pedicle part was (30.52 ± 0.62) °C 3 days after the operation in the experimental group, significantly higher than those in the control group[ (28.95 ± 1.06), (29.05 ± 1.23) and (29.31 ± 1.19) °C respectively] (t = 2.12, 1.99 and 2.31, P < 0.05). Conclusion: NGF can promote the survival status by increasing blood flow velocity of the ultra-long random flap.

Aim: To study the effect of locally using exogenous nerve growth factor (NGF) on promoting ultra-long random flap survival. Methods: The animal model of random flap in rat back was adopted. NGF 66.7 μg were locally injected once only in trial group after operation with auto-control. The survival area and rate of random flap were observed continuously, and also the blood flow changes were measured by the laser and fiber optic in different time. Results: The survival area and rate of random flap in trial group [(7.12 ± 1.54) cm2, (92 ± 5)%] were obviously higher than those in control group[(5.23 ± 0.19) cm2, (69 ± 5)%] (t = 2.33, P < 0.05) after pedicle division. The blood flows in the middle and at the end of flap in the trial group[(0.138 ± 0.065), (0.082 ± 0.026) mL/min · g respectively] were significantly higher than those in control group[(0.086 ± 0.031), (0.051 ± 0.037) mL/min · g respectively] (t = 2.05, 2.41, P < 0.05) 24 h after operation. The blood flow of the pedicle (0.184 ± 0.050) mL/min · g in trial group was higher than that in the control group (0.141 ± 0.044) mL/min · g, (t = 2.29, P < 0.05) at 5 day. The blood flow of three parts of end, middle and pedicle in both groups changed significantly[(0.151 ± 0.051), (0.174 ± 0.048), (0.168 ± 0.057) mL/min · g in trial group, and(0.088 ± 0.062), (0.108 ± 0.055), (0.117 ± 0.076) mL/min · g in control group] (t = 5.17, 4.79, 2.76, P < 0.01) at 7 day. Conclusion: NGF can promote survival status by increasing blood flow of the ultra-long random flap.