紫花烧伤膏对大鼠随意型皮瓣成活的影响

目的 观察紫花烧伤膏对大鼠皮瓣存活的影响,并探讨其作用机制.方法 Wistar 大鼠72只,随机分为紫花组(外用紫花烧伤膏)、阳性对照组(外用海普林乳膏)、阴性对照组(未手术组)和模型组(外用凡士林),每组18只.在大鼠背部设计蒂在头侧的8 cm×2 cm的随意型皮瓣,2次/日涂药,观察大鼠皮瓣成活情况;比较术后1、2、3和7d血清超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)、肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)的变化并行组织形态学检查.结果 皮瓣成活面积百分比:紫花组(73.58±10.74)％,模型组(33.40±16.05)％,紫花组比模型组提高了54.61％ (Q =10.63,P＜0.01),与海普林组(71.65±11.92)％比较,差异无统计学意义(P＞0.05);紫花组血清SOD和NO含量高于模型组,MDA、TNF-α和IL-6含量低于模型组(P＜0.01),与海普林组比较,差异无统计学意义(P＞0.05).术后7d紫花组与海普林组皮瓣组织水肿、坏死及炎性细胞浸润较模型组轻,肉芽组织、成纤维细胞增生明显,紫花组有大量新生的毛细血管形成,皮瓣血管所占面积明显高于模型和海普林组(P＜0.01).结论 紫花烧伤膏可明显改善大鼠皮瓣血液循环,提高皮瓣的成活率,其机制可能与抗自由基损害、改善局部微循环、提高NO的含量、降低TNF-α和IL-6水平、减少炎性因子释放,改善氧化应激状态,减轻炎性反应有关.     

会阴部皮肤缺损的修复

采用胸脐皮瓣，腹股沟皮瓣，大腿外侧皮瓣，大阴唇皮瓣修复会阴部皮肤缺损２２例。皮瓣的选择主要根据缺损组织的范围和功能。胸脐皮瓣的优点是不受受区条件的限制，可提供的皮瓣面积大。腹股沟皮瓣优点是操作简便。大腿外侧皮瓣游离移植可降低会阴部的创伤。大阴唇皮瓣主要用于阴道再造。     

前列环素对任意型皮瓣成活影响的实验研究

为观察前列环素(PGI_2)对皮瓣成活的影响,以大白鼠背部设计超长任意型皮瓣模型,设立术前(预防组)、术后(治疗组)静脉给 PGI_2及生理盐水对照组,对皮瓣的血供、代谢和血液流变学等进行分析。结果表明治疗组皮瓣远端血流相对值为41.3%,对照组为22.4%,治疗组皮瓣成活率明显高于对照组,预防组与对照组相比无明显差异。提示:术后早期给予 PGI_2可以改善皮瓣的血流和血液流变状态,提高皮瓣成活面积。     

Wound healing at adaptation zones of skin flaps harvested from acute burned skin

Background

Early reconstruction of burn defects culminates in more successful results. The wound healing process of the burned skin affects not only the curative phase of the burned area but also result of any reconstructive procedure including the regional flaps. Thus, in this study, we have evaluated the wound healing process at the distal incisions of random-pattern skin flaps prepared from burned dorsal skin of rats.

Materials and methods

Thermal burn damage was performed with dimensions of 3 cm × 3 cm on Wistar albino rats. In group 1 (n = 12), no burn was produced and 3 cm × 3 cm caudally based, random-pattern skin flaps were elevated. In group 2 (n = 12), a 5 cm × 5 cm area of partial-thickness thermal damage was produced and after three days a 3 cm × 3 cm random-pattern skin flap was elevated as in group 1 inside the burned skin site. In group 3 (n = 12), 3 cm × 3 cm area of partial-thickness thermal damage was produced and after three days 3 cm × 3 cm random-pattern skin flap was elevated. In group 4 (n = 12), 3 cm × 3 cm area of partial-thickness thermal damage was produced and after three days a 3 cm × 3 cm random-pattern skin flap was elevated at the distal margin of the burned area. The flaps were adapted to the donor sites in all groups. The histopathological evaluation was done and hydroxyproline levels were measured.

Results

There were no significant differences between groups regarding presence of epithelialization, myofibroblast numbers, and collagen texture (p > 0.05). Neovascularization level was significantly higher in group 2 than the other groups (p < 0.05). There were no statistically significant difference among the hydroxyproline levels in all four groups (p > 0.05).

Conclusion

The preference of the incision site in a burn zone while designing a flap during the acute burn period was proposed to possess no difference in terms of wound healing in an animal model.     

微循环监测方法在皮瓣断蒂前的应用

目的监测腹股沟外侧皮瓣微循环血流动态变化及其规律,为选择最佳断蒂时间提供可靠客观量化指标.方法应用激光多普勒血流计(LDF)对12例腹股沟外侧皮瓣移转面中点逐日进行微循环监测,皮瓣移植后第4 d起记录皮瓣蒂部阻断前、后LDF的灌注单位(perfusion units,PU)值变化情况.结果腹股沟外侧皮瓣微循环血流变化可分为两期,即术后前6 d的骤升期,PU值分别为2.83±0.46、3.21±0.41、3.66±0.43、4.77±0.71、7.08±0.37;术后6～11 d的平台期,PU值分别为7.53±0.41、7.57±0.62、7.70±0.44、7.60±0.26、7.58±0.17.本组断蒂时间为术后8～11 d. 结论腹股沟外侧皮瓣移转用以修复手背及腕部缺损,其微循环血流变化在平台期稳定期时,在阻断皮瓣蒂部后其PU值恢复到或超过阻断前水平的50%时进行断蒂,皮瓣全部成活.     

前列环素对任意型皮瓣成活影响的实验研究

为观察前列环素（ＰＧＩ２）对皮瓣成活的影响，以大白鼠背部设计超长任意型皮瓣模型，设立术前（预防组）、术后（治疗组）静脉给ＰＧＩ２及生理盐水对照组，对皮瓣的血供、代谢和血液流变学等进行分析。结果表明治疗组皮瓣远端血流相对值为４１．３％，对照组为２２．４％，治疗组皮瓣成活率明显高于对照组，预防组与对照组相比无明显差异。提示：术后早期给予ＰＧＩ２可以改善皮瓣的血流和血液流变状态，提高皮瓣成活面积。     

前列环素对任意型皮瓣成活影响的实验研究

为观察前列腺素（ＰＧＩ２）对皮瓣成活的影响，以大白鼠背部设计超长任意皮瓣模型，设立术前（预防组），术后（治疗组）静脉给ＰＧＩ２及生理盐水对照组，对皮瓣的血供，代谢和血液流变学等进行分析，结果表明治疗组皮瓣端血流相对值的４１．３％，对照组为２２．４５，治疗组皮瓣成活率明显高于对照组，预防组与对照相比地明显差异，提示：术后早期给予ＰＧＩ２可以改善皮瓣的血流和血液流变状态，提高皮瓣成活面积。     

Response of random skin flaps to rapid expansion

We studied the physiologic accommodation of tissues to 5-day expansion in a porcine random flap model to assess the time taken to expand skin to provide early coverage of traumatic defects. Three 6 X 20 cm random flaps were outlined but not elevated on the backs of 12 small (20-kg) pigs. One flap was not manipulated (control). A 450-ml expander was inserted at the base of the second flap and left in place (sham). At the base of the third flap a 450-ml expander was inserted and sequentially filled to the limits of skin viability each day for 5 days (expanded). Skin tension produced by the pressure of expansion and tissue oxygen (TpO2) in each flap were measured before and after each manipulation. Flaps were raised on day 8, and survival determined on day 15. Creation of the pocket reduced TpO2 to 55% of control values, expansion to 17.5% of control. Within 24 hours both sham and expanded had recovered to 80% of control values. After the second expansion, recovery from hypoxia was again almost complete after 24 hours. Recovery after subsequent expansions was less complete, but 3 days after the final expansion there was no statistical difference between TpO2 values in expanded, sham, and control groups. High pressures generated in the flap by expansion also returned to near normal within 24 hours. Flaps utilizing expanded skin survived to greater length (14.2 cm) than did sham (11.6 cm) or control (7.2 cm) flaps (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

阴股沟皮瓣修复手部软组织缺损

应用吻合血管的阴股沟游离皮瓣修复手部软组织缺损１３例均获得成功，效果满意。该皮瓣薄，皮下脂肪少，移植后外形不臃肿，供区隐蔽，创面可直接缝合，是修复手部软组织缺损的理想供区。     

超薄皮瓣和全厚皮片联合体成形治疗四肢大面积皮肤撕脱伤

目的 探讨整合超薄皮瓣和全厚皮片回植治疗四肢大面积皮肤撕脱伤的临床效果.方法 2002年4月至2007年10月应用超皮瓣和全厚皮片联合体成形回植治疗四肢大面积皮肤撕脱伤患者21例.根据皮肤损伤特点和创面情况,将撕脱皮肤自游离缘向蒂部的绝对缺血区、部分缺血区和供血相对正常区分别修剪成皮片区、交界区和超薄皮瓣区,将成形的联合体回植修复创面.结果 本组21例,撕脱皮肤占体表面积2%～6%,平均3.3%,成活皮肤面积占撕脱皮肤90%～100%,平均94.1%,无创面感染,随访12例,一年后回植皮肤质地柔软,无明显挛缩,功能基本恢复.结论 本术式有效地整合超薄皮瓣和全厚皮片移植的优点,最大限度地保存了撕脱皮肤的形态学特点,提高撕脱皮肤成活率,手术简单安全易行.     

Effects of hyperbaric oxygen and N-acetylcysteine in survival of random pattern skin flaps in rats

Objective:

Our aim is to investigate the role of HBO (hyperbaric oxygen), NAC (N-acetylcysteine), and HBO plus NAC on the necrosis area of random rat''s skin flaps of a modified McFarlane flap design.

Materials and Methods:

Thirty-two male Wistar rats were randomly divided into four groups: G-S (sham: n = 8), G-NAC (NAC: n = 8), G-HBO (HBO: n = 8), and G-HN (HBO plus NAC: n = 8). A rectangular skin flap (2 × 8 cm²) was dissected from the muscular dorsal layer, preserving the cranial pedicle. Polyethylene film was placed over the muscular layer and an interrupted 3.0 nylon suture was employed to fix the flap into the original place. On the eighth day, full-thickness biopsy samples (2 × 1 cm²) were collected from the proximal, middle, and cranial areas of the skin flap, and in a site away from the flap labelled as the control area.

Results:

The measurements of necrotic areas in the groups were 18.3% in G-S, 24.3% in G-NAC, 12.6% in G-HBO, and 14.9% in G-HN. Significant difference was observed between the groups G-HBO and G-HN as well as G-NAC.

Conclusion:

HBO is associated with reduced area of necrosis of skin flap. The G-NAC group was associated with poor results when examined in isolation. The association between HBO and NAC did not produce favourable results with respect to the use of HBO alone. These findings suggest that the diffusion of oxygen through the interstitial space was the determining factor of more favourable results of HBO.KEY WORDS: Acetylcysteine, hyperbaric oxygenation, necrosis, surgical flaps     

Intraoperative use of dynamic infrared thermography and indocyanine green fluorescence video angiography to predict partial skin flap loss

Inadequate perfusion is the most common cause of partial flap loss in reconstructive surgery. Intraoperative monitoring of flap perfusion may prevent such loss. This study compared indocyanine green fluorescence angiography (ICG-FA) and dynamic infrared thermography (DIRT) in their ability to predict intraoperatively the percentage of flap survival in a caudally based McFarlane flap in 10 male Wistar rats. The intraoperative images of both techniques were subjectively and objectively analysed. The percentage of flap survival, as judged from the digital colour photographs 7 days post-operatively, was 69 ± 3%. Objective analysis of flap survival based on intraoperative DIRT and ICG-FA (74 vs 63%, respectively) correlated quite well with the subjective measurements (75 ± 2 vs 59 ± 4%, respectively). However, intraoperative ICG-FA images underestimated flap survival by 6–10%, while intraoperative DIRT images overestimated the flap survival by 5–6%. The authors conclude that intraoperative use of ICG-FA and DIRT can provide valuable information on areas with inadequate perfusion as long as their limitations are respected.     

Prevention of unfavourable effects of cigarette smoke on flap viability using botulinum toxin in random pattern flaps: An experimental study

BACKGROUND:

There are numerous clinical and experimental studies reporting unfavourable effects of cigarette smoke on skin flaps.

OBJECTIVE:

To investigate whether unfavourable effects of cigarette smoke on flap survival could be reduced by botulinum toxin type A.

METHODS:

Twenty-eight male Wistar albino rats (15 months of age, mean weight 210 g [range 180 g to 230 g]) were included. They were divided into four groups of seven animals each. The control group underwent the surgical procedure alone. Surgical procedure was performed after administration of botulinum toxin type A in the botulinum toxin (BTX) group, after exposure to cigarette smoke in the cigarette smoke (CS) group, and after BTX type A administration and exposure to CS in the CS+BTX (CS+BTX) group. Random pattern cutaneous flaps (3 cm × 9 cm) were elevated from the dorsum of all rats. Necrosis area was calculated in percentages (%) using Image J computer software. Tissue samples were examined histopathologically.

RESULTS:

The mean necrotic area in the control group (26%) and in the BTX group (21%) were similar (P=0.497), whereas administration of BTX type A significantly decreased flap necrosis area in the rats exposed to CS (the mean necrosis areas were 41.5% in the CS group, and 26% in the CS+BTX group; P<0.001). Histopathological examination findings corroborated the unfavourable effects of CS and preventive effects of BTX type A.

CONCLUSION:

Preoperative administration of BTX significantly enhanced flap viability in the rats exposed to CS. Further human studies are warranted to verify whether BTX type A could be used as an agent to reduce the risk of flap necrosis in patients who smoke.     

Improved survival of ischemic random skin flaps through the use of bone marrow nonhematopoietic stem cells and angiogenic growth factors

Surgical skin flaps are frequently used in plastic and reconstructive surgery to repair acquired or congenital defects. Necrosis is a common complication associated with these flaps postoperatively as a result of inadequate blood supply. Stem cells are precursor cells with the potential to differentiate into more specialized cells. Angiogenic factors act to direct cellular differentiation and organization to form new vascular elements. Our theory was that the combination of angiogenic growth factors with stem cells derived from the subject preoperatively would augment neovascularization, thereby increasing blood supply to the flap, which may ultimately improve flap survival. In phase I, 40 Lewis rats were randomized into 4 groups of 10. Random dorsal skin flaps were elevated and treated at the same time. The first group was injected with only medium, the second with stem cells, the third with stem cells and angiogenic factors, and the fourth with angiogenic growth factors. Millimetric measurements of flap viability at 7 and 14 days did not show any statistically significant differences between the studied groups. In phase II, 24 rats were also randomized into 4 groups of 6, but this time were treated 1 week before flap elevation. The viability measurements showed an increased rate of viability in the group in which stem cells and the angiogenic factors were administered simultaneously (84.5% +/- 3.2%) as compared with the unmodified control group (62.6% +/- 7.3%) or to the groups in which only precursor cells (60.4% +/- 7.9%) or angiogenic factors (62.3%+/- 10.1%). Increased blood supply brought by these manipulations is believed translated to increased tissue flap survival. Punch biopsies showed that "green fluorescent protein"-labeled precursor cells was noted to form luminal structures in the treated flaps. The vascular cast of all flaps was filled with Mercox plastic resin. After euthanasia, the soft tissues of the harvested flaps were dissolved and the remaining vascular cast was weighted. The weight-based ratio of the vascular composition was determined. The flaps injected with both stem cells and angiogenic factors showed higher values. We conclude that the administration of bone marrow stem cells with angiogenic factors 1 week before flap creation improves the survival of ischemic random skin flaps.     

Resistance of rapidly expanded random skin flaps to bacterial invasion

This study tested the hypothesis that rapidly expanded random pattern skin flaps demonstrate enhanced resistance to bacterial invasion from intradermal injection of Staphylococcus aureus in a porcine model. Sites for a 6 X 12 cm expanded, a 6 X 9 cm sham-expanded, and a 6 X 6 cm acute random pattern skin flap were outlined, but not elevated, on the backs of 14 white pigs. A 450-cc tissue expander inserted beneath the panniculus carnosus at the site for expansion was sequentially filled to the limits of skin viability each day for 5 days. At the sham site a tissue expander was similarly inserted but left unexpanded; the acute flap site was left undisturbed. On day 8, flaps were elevated, immediately sutured in place, and 0.1 ml of saline solution containing 10(7) Staphylococcus aureus inoculated intradermally at four corresponding sites in each flap and at three sites in normal skin. In seven animals these sites were at the proximal base of the flaps; in seven others the sites were distal. The resulting areas of erythema and skin ulceration were measured on each of the next 3 days and the measurements compared. At corresponding proximal sites, the mean area of erythema and ulceration measured over the next 3 days in expanded flaps (31.2 mm2) and in sham-expanded flaps (33.8 mm2) was significantly less than in acute flaps and control skin (47.5 mm2, 43.4 mm2, p less than 0.05). Measurements in the rapidly expanded flaps were not significantly different than those in the sham-operated expanded flaps.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of contraction rates of epigastric and extended dorsal island skin flaps in rats

Flap surgery is a wide field in plastic and reconstructive surgery practice and experimental research is needed to improve surgical success. These research is often performed on rats. Rat is a loose-skinned animal and contraction of skin flaps on rats is an underestimated condition. Besides this variable contraction of survived and necrotic tissues may mislead calculations and results. In this study, contraction patterns of epigastric and dorsal island skin flaps were investigated to identify this phenomenon. Forty-two male Sprague-Dawley rats were divided into four groups. Eleven epigastric flaps with unilateral pedicles, 11 epigastric flaps with bilateral pedicles, 10 extended dorsal island skin flaps with unilateral pedicles, and 10 extended dorsal island skin flaps with bilateral pedicles were prepared. Total, necrotic and viable flap areas were calculated from standardized photographs which were taken daily. The animals were placed on marked papers and image processing software was used the calculate flap areas from the photographs. Respect to these daily flap areas, the contraction rates in epigastric flaps were highly significant. The area loss in necrotic tissues were faster than the viable areas. Compared to the epigastric flaps, the contraction was not significant in extended dorsal island skin flaps flap groups. In conclusion, the rat extended dorsal island skin flap is a more reliable model for experimental flap research, which is resistant to contraction, when compared to the epigastric skin flap model.     

海普林对大鼠皮瓣成活影响的实验研究

目的 探讨外用药海普林软膏对皮瓣血液循环的影响，以期为挽救临床已出现循环危象的皮瓣提供一种新方法。方法 采用随机对照的方法将80只大鼠随机分为实验组和对照组，分别观察其背部随意型皮瓣成活与坏死面积，并进行组织学检查,记数断面毛细血管数。结果 组织学观察术后5，7d皮瓣远端两组均为全层坏死，术后5d皮瓣中断面毛细血管记数经统计学处理两组无显著性差异（P＞0．05），术后7d皮瓣中段断面毛细血管记数实验组明显多于对照组，统计学处理两组有显著性差异（P＜0．05）。结论 海普林软膏可明显改善皮瓣血循环。