负压封闭引流对兔创面氧分压及愈合的影响

目的 观察负压封闭引流(VSD)术后不同负压值对兔创面局部氧分压和愈合的影响。方法 建立兔创面模型12只并随机分组,其中实施VSD手术6只(负压组),以不同负压值(-75 mmHg、- 125 mmHg、- 225 mmHg和-350 mmHg)(1 mmHg=0.133 kPa)持续吸引7d,分别于各时间点用组织氧分压测量仪监测创面局部组织氧分压( Pt02)变化;用游标卡尺测量并计算VSD敷料和创面大小的变化;用细菌培养检测创面有无厌氧菌生长;用光镜观察HE染色后创面的组织形态学改变和愈合情况,并同时设立建模前实验兔(正常组)、VSD假手术实验兔(假手术组)和建模后常规换药实验兔(常规组)各6只进行对照。结果 负压组PtO2为(1.68±0.03) kPa且7d内逐步降低,常规组Pt02为(2.82±0.37) kPa,正常组Pt02为(5.79±0.50)kPa,负压组PtO2较常规组和正常组显著性降低,差异具有统计学意义(P＜0.01),且随着负压值的增高,同一时间点的Pt02进一步降低;术后5s时即降为初始Pt02的80.94％。VSD敷料经负压吸引后面积显著性缩小,差异具有统计学意义(P＜0.01),术后5 min即缩小为原敷料面积的65.36％。经物理负压治疗,负压组创面面积较常规组显著性缩小,差异具有统计学意义(P＜0.01),术后7d时缩小为初始面积的62.82％。其中- 350 mmHg组的创面变化率显著性高于其他组,差异具有统计学意义(P＜0.01)。术后负压组创面未见厌氧菌生长。结论 VSD技术可显著降低创面PtO2,且未见厌氧菌生长。- 350 mmHg压力下可显著缩小VSD敷料,协助收敛创面,促进创面的愈合。

Effects of vacuum sealing drainage on oxygen partial pressure and wound healing in rabbits

Objective To investigate the effect of vacuum sealing drainage (VSD) with different negative pressures on variation of oxygen partial pressure (PtO2 ) and wound healing in the rabbits.Methods Twelve rabbit wound models were made and randomly (random number) divided into two groups, namely vacuum group ( n =6 ) in which rabbits were treated with VSD by different negative pressures ( - 75 mmHg, - 125 mmHg, - 225 mmHg and - 350 mmHg) for 7 days, and routine treatment group ( n =6). At each interval of measurement, variation of PtO2 was measured by oxygen partial pressure admeasuring device, and area of VSD dressing and surface of wound were measured by vernier caliper, and growth of anaerobic bacteria was detected by bacterial culture, and morphological change and the course of wound healing were observed under by light microscope after HE tissue staining. Meanwhile anther two groups (n =6, in each) were set for comparing, including normal group, sham operation group. Results Average PtO2 value of vacuum group was in the range of ( 1.87 +0. 19) kPa to ( 1.54 ±0. 21 ) kPa which was decreased gradually in 7 days under different negative pressures. Average PtO2 value of routine treatment group and normal group were ( 2. 82 ± 0. 37 ) kPa and ( 5.79 + 0. 50 ) kPa, respectively which weresignificant higher than that in vacuum group ( P ＜ 0. 01 ). PtO2 was fell to 80. 94％ of its original value after VSD for 5 seconds, and continued the downward trend with the increasing of negative pressure at the same interval of measuring. Area of VSD dressing significantly decreased to 65. 36％ of its original area after VDS for5 minutes (P＜0.01). Surface of wound was minimized to 62. 82％ of its original area after VSD for 7 days ( P ＜ 0. 01 ), and variations of those in - 350 mmHg group were significant greater than those in other groups ( P ＜ 0. 01 ). There was no evidence of anaerobic bacteria growth in vacuum group during this experiment. Conclusions PtO2 could be down-regulated by VSD significantly without growth of anaerobic bacteria, and minimization of VSD dressing at - 350 mmHg was significantly helpful to reduce the area of wound for promoting the healing.