Babovic S, Angel M F, Im M J, Ress A M, Manson P N
Division of Plastic, Reconstructive and Maxillofacial Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
Ann Plast Surg. 1995 Jun;34(6):593-8. doi: 10.1097/00000637-199506000-00005.
The effects of tissue expansion on free flap tolerance and metabolic response to secondary ischemia were evaluated. A total of 178 male syngeneic Lewis rats were used: 28 in perfusion study and 75 donor and 75 recipient animals in flap survival study. Animals were organized in three experimental groups: control, sham operation, and expansion group. Sham group animals had the expander implanted but not insufflated. After 4 weeks of tissue expansion, 3 x 5-cm epigastric free flaps were transplanted to recipient animals. Twenty-four hours later, secondary ischemia was produced by 3-hour venous occlusion. Flap survival, perfusion, and enzyme activities were determined. Pre-expanded skin flaps had an increase in perfusion of approximately 700% as measured by fluorescein levels compared with control flaps (p < 0.001) and demonstrated a better success rate (76%) compared with those of the control (40%) (p < 0.05) and sham (28%) groups (p < 0.05). Glutathione peroxidase, glutathione reductase, and glucose 6-phosphate dehydrogenase of the antioxidant defense systems significantly increased in skin in both the sham and the expansion groups. In response to secondary ischemia, the control and sham groups exhibited a decrease in enzyme activities of the glutathione redox cycle, whereas the expansion group showed no significant changes from the elevated baseline activities. Tissue expansion improved flap tolerance to secondary ischemia by increasing flap circulation and probably by augmenting tissue metabolic response to oxidative stress.
评估了组织扩张对游离皮瓣耐受性及对二次缺血的代谢反应的影响。总共使用了178只雄性同基因Lewis大鼠：28只用于灌注研究，75只作为供体动物，75只作为皮瓣存活研究的受体动物。将动物分为三个实验组：对照组、假手术组和扩张组。假手术组动物植入扩张器但不进行注水。在组织扩张4周后，将3×5厘米的上腹部游离皮瓣移植到受体动物身上。24小时后，通过3小时的静脉闭塞造成二次缺血。测定皮瓣的存活情况、灌注情况及酶活性。与对照皮瓣相比，预扩张皮瓣通过荧光素水平测量的灌注增加了约700%（p<0.001），与对照组（40%）（p<0.05）和假手术组（28%）（p<0.05）相比，显示出更高的成功率（76%）。假手术组和扩张组皮肤中抗氧化防御系统的谷胱甘肽过氧化物酶、谷胱甘肽还原酶和葡萄糖6-磷酸脱氢酶均显著增加。对二次缺血的反应中，对照组和假手术组谷胱甘肽氧化还原循环的酶活性降低，而扩张组与升高的基线活性相比无显著变化。组织扩张通过增加皮瓣循环并可能通过增强组织对氧化应激的代谢反应，提高了皮瓣对二次缺血的耐受性。
