皮瓣抛起后内皮素,一氧化氮变化与微循环关系的实验研究

目的 研究皮瓣抛起后内皮素（ＥＴ）、一氧化氮（ＮＯ）动态变化与皮瓣微循环的关系,并探讨ＥＴ、ＮＯ在真皮下血管网皮瓣超长成活中的作用。 方法 在猪背部制备真皮下血管网皮瓣和任意型皮瓣,术前、术后测定皮瓣组织ＥＴ、ＮＯ含量及微循环血量。结果 两组皮瓣ＥＴ、ＮＯ量术后１ｈ开始明显上升,ＮＯ３ｈ达到峰值,ＥＴ６ｈ达到峰值;术后１,３,６ｈ ＥＴ量在任意型皮瓣组上升更显著（Ｐ〈０．０５）,而ＮＯ量在真皮下血     

一次性软组织扩张的实验研究

为了探索一次性软组织扩张的可能性，应用激光多普勒微循环血流仪（ｌａｓｅｒｄｏｐｐｌｅｒｆｌｏｗｍｅｔｅｒ，ＬＤＦ），在９只健康雄性白色乳猪躯干部作一次性软组织扩张术（ｉｎｔｒａｏｐｅｒａｔｉｖｅｓｕｓｔａｉｎｅｄｌｉｍｉｔｅｄｅｘｐａｎｓｉｏｎ，ＩＳＬＥ），共对５４个ＩＳＬＥ扩张的皮肤进行微循环监测，同时对扩张囊内压力与ＩＳＬＥ皮肤血流的相关性及ＩＳＬＥ皮肤病理学变化进行了探讨。结果表明：一次性扩张的皮肤，其微循环灌注量显著高于对照组，可提供更多的额外皮肤。为临床应用一次性软组织扩张技术提供了实验依据     

皮肤外扩张延迟作用的实验研究

临床上进行皮肤外扩张治疗过程中，发现外扩张后的皮肤有类似延迟的作用。为探索其变化的机理，选用２０只新西兰大白兔，随机分为２组，实验组为皮肤外扩张组，对照组为不扩张组。各组应用激光多普勒血流计（ＬＤＦ）及血氧饱和度（ＳｐＯ２）检测计进行皮肤微循环血流监测，并对２组皮瓣成活面积及微血管造影的结果进行比较。结果表明：实验组１２天后，ＬＤＦ值比未扩张前增高，ＳｐＯ２值恢复到扩张前水平；皮瓣成活面积明显高于对照组；微血管造影皮下血管吻合支明显增多。认为，外扩张后的皮肤生存质量未较正常皮肤下降，并有近似于延迟的作用。     

短程持续组织扩张技术的临床应用

目的：研究住院周期最短的理想快速扩张法。方法：选择１１７例皮肤瘢痕患者,分成间断快速扩张组（ＩＦＴＥ）和短疗程持续扩张组（ＳＰＴＥ）。ＩＦＴＥ组采用平行切口埋植扩张器,术后１０天开始作间断快速扩张。ＳＰＴＥ组经垂直小切口埋植扩张器,术中大量注水扩张,术后持续扩张。结果：所有患者均顺利完成快速扩张并获得满意治疗效果。ＩＦＴＥ组平均扩张时间１６．８天,平均住院时间为４５．３天。ＳＰＴＥ组平均扩张时间为     

皮肤软组织扩张术的应用进展

皮肤软组织扩张术(Ｓｋｉｎｔｉｓｓｕｅｅｘｐａｎｓｉｏｎ,ＳＴＥ1976)是通过增加置入皮下扩张器内的容量,对表面皮肤产生压力,使其产生“额外”皮肤,利用新增加的皮肤转移覆盖创面。ＳＴＥ为烧伤、创伤瘢痕、肿瘤、缺损的修复重建增添了新的较为满意的方法,是整形外科领域里程碑性的进展[1]。一、皮肤软组织扩张术的基础研究1.扩张后的组织学变化:皮肤经过一定容量的扩张后,局部面积增加。扩张表皮细胞的有丝分裂活动24ｈ内可增加3倍。有新生的细胞形成。表皮细胞对机械刺激反应敏感,皮肤软组织扩张时的有丝分裂活动是正常组织对张力的一…     

远红外线对鼠随意皮瓣成活的影响

为了观察远红外线照射对实验性皮瓣成活的影响，采用４８只ＳＤ大鼠，在背部掀起皮瓣２ｃｍ×６ｃｍ。从术前３ｄ至术后第５ｄ，应用远红外线照射大鼠皮瓣，观测皮瓣掀起后即刻的微循环变化和术后７ｄ成活情况。结果显示，远红外线组皮瓣近、远端微血管开放率、流动微血管口径和流速均高于对照组，经统计学处理有显著差异（Ｐ＜０．０５），皮瓣成活率较对照组的６２．７％提高到照射组的８０．５％（Ｐ＜０．０１）。研究结果表明，远红外线能扩张微血管，改善微循环，增加皮瓣血流量，提高皮瓣成活率。     

先天性心脏病心内直视手术对血浆内皮素的影响

目的　探讨先天性心脏病（ＣＨＤ） 围术期血浆内皮素（ＥＴ） 的变化。　方法　将６７ 例行心肺转流术（ＣＰＢ）的ＣＨＤ 患儿按疾病种类不同分为３ 组,室间隔缺损（ＶＳＤ） 组、肺动脉高压（ＰＨ） 组和肺动脉狭窄（ＰＳ） 组;１０ 例正常儿童为对照组。对前３ 组手术前后血浆ＥＴ 变化进行动态观测。　结果　ＰＨ 组和ＰＳ组术前ＥＴ 值即有升高,术后７ 天仍较对照组为高;ＣＰＢ３０ 分钟时各组ＥＴ 值均较术前为低;术前血浆ＥＴ 值与ＰＳ和ＰＨ 程度呈线性相关;ＰＳ组ＣＰＢ 时间和主动脉阻断时间与术后１ 小时ＥＴ 值明显相关。　结论　ＣＨＤ 患儿手术前、后血浆ＥＴ 值均有变化,血浆ＥＴ 水平可作为监测肺动脉压力变化及ＣＨＤ 手术预后的指标之一。     

iNOS在扩张皮肤组织中的表达及其意义

目的研究催化一氧化氮生成的关键酶之一,诱导型一氧化氮合酶（iNOS）在扩张皮肤组织中的表达,并探讨其意义。方法将取自18例行皮肤软组织扩张术患者的扩张皮肤18份标本（扩张组）及自身对照的正常皮肤10份标本（正常组）,采用免疫组化方法检测扩张皮肤组织及正常皮肤组织中的iNOS、CD34、增殖性细胞核抗原（PCNA）的表达。结果扩张组中iNOS的表达较正常组的表达显著增强（P〈0.05）,正常组的在表皮基底层有弱阳性表达,扩张组的在表皮基底层有强阳性表达。扩张组中的真皮乳头微血管数较正常组的显著增多（P〈0.05）;PCNA标记指数（PLI）无统计学意义（P=0.062〉0.05）。扩张组中的iNOS表达水平与血管密度计数（MVD）呈显著正相关（R=-0.715,P〈0.05）。与PLI无显著相关性（R=-0.27,P=0.278〉0.05）。结论iNOS在扩张皮肤组织中的表达增强,高水平表达的iNOS可能会通过促进扩张皮肤组织中真皮乳头血管的形成而促进皮肤的扩张。     

体外循环心内直视手术对心血管调节肽影响的初步临床研究

作者对１５例体外循环心内直视手术病人的内皮素（ＥＴ）、降钙素基因相关肽（ＣＧＲＰ）、神经降压素（ＮＴ）和Ｐ物质（ＳＰ）进行测定，结果提示：（１）ＣＰＢ手术病人术前ＥＴ含量明显高于术中及术后（Ｐ＜０．０１），开放循环心脏复苏后，体内ＥＴ含量达到了最低水平，回ＩＣＵ及术后２４小时，ＥＴ含量回升，但仍明显低于术前；（２）ＣＰＢ期间ＣＧＲＰ无明显变化，术后２４小时体内ＣＧＲＰ水平明显较术前及术中升高（Ｐ＜     

肾移植患者术后早期血浆内皮素的变化

对３２例尸体肾移植患者术前及术后早期３个月的血浆内皮素－１（ＥＴ－１）浓度进行了动态观察，同时行前列腺素Ｅ－２（ＰＧＥ－２）、血栓素Ｂ－２（ＴＸＢ－２）与环孢素Ａ（ＣｓＡ）血浓度的测定及移植肾功能与血压的监测。ＥＴ－１、ＰＧＥ－２及ＴＸＢ－２均采用放射免疫法测定，ＣｓＡ血浓度采用多克隆抗体偏振免疫荧光法（ＴＤＸ）进行。结果显示：移植前患者的血浆ＥＴ－１平均浓度为１０．２７±０．５７ｐｇ／ｍｌ，移植后３个月各阶段的ＥＴ－１值均显著降低，平均浓度为４．６２±０．１４ｐｇ／ｍｌ。与此同时，血浆Ｃｒ和ＢＵＮ值以及收缩压、舒张压也呈现相似的变化，与移植前相比有非常显著性差异（Ｐ＜０．０１），且血浆ＥＴ－１浓度的变化与移植肾功能及血压密切相关。血浆ＥＴ－１浓度可作为肾移植术后的一项监测参考指标。     

Hemodynamics in skin and tissue expansion]

The capillary blood flow (CBF) of the random flaps constructed on expanded and unexpanded skin of dogs was determined by radioactive microsphere technique. The CBF was significantly higher (P < 0.001) in the skin flaps of the expanded group (387 +/- 23 microliters/min/flap) than that of the acute group (127 +/- 16 microliters/min/flap). There were no significant differences in the expanded group, the delayed group (374 +/- 35 microliters/min/flap) and the control group (389 +/- 48 microliters/min/flap). Even at the pedicle site, the CBF of the acute group was already significantly lower than that of other three groups (P < 0.001). The general tendency of gradual CBF reduction from the pedicle to the distal end of all the flaps was observed. The CBF at the point 8cm from the pedicle of the acute group was 12 microliters/min/g, whereas in other three groups, at point 13 cm from the pedicle the CBF was 12 microliters/min/g. The results suggested that during skin expansion the area of skin is enlarged, and its CBF and survival length may be increased. The problem of capsulectomy during flap construction was discussed.     

Enhanced capillary blood flow in rapidly expanded random pattern flaps

We have quantitatively examined the effect of rapid sequential skin expansion on capillary blood flow in the porcine random flap model in order to determine the relation between the increased survivability of expanded random flaps and capillary blood flow. Three 6 X 20 cm random flaps were tattooed on the backs of six 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 each day for 5 days sequentially filled to the limits of skin viability as determined by vital dye staining (expanded). Capillary blood flow was measured on day 8 by measurement of radioactivity after injection of 15-microns radiolabeled microspheres. Samples were taken at 4-cm intervals from the base of each flap. Rapid expansion led to significant increases in capillary blood flow in expanded skin and to enhanced preservation of capillary flow after elevation of random pattern flaps based on expanded skin compared to sham and to control tissues. This correlates with and explains at least in part our previous observation of improved length of survival of flaps raised on expanded skin.     

超量扩张皮肤血流量改变的初步临床观察

目的 探讨超量扩张时皮肤血流量的变化与皮瓣存活的关系。方法 对临床10例患者21个扩张器在扩张器置入前、满量、超量注水时，应用激光多谱勒血流测定仪测定扩张皮肤微循环血流量及其波幅，并与最终临床效果进行观察比较。结果 正常皮肤血流量及血管的运动波较小且较稳定，扩张后尤其是超量扩张后其血流量明显增加。与正常皮肤相比差异有统计学意义（P〈0．05），血管的运动波与正常皮肤相比差异亦有统计学意义（P（0．05），与超量注水扩张皮肤相比差异有显著的统计学意义（P（0．01）。结论 扩张皮肤血流量的增加，主要表现为血管数量的增加和增粗，当扩张皮瓣的长宽比例较大时，尤其在过度扩张时，扩张皮肤的血供不像延迟皮瓣具有方向性，加上微血管括约肌的功能异常，更易出现皮瓣远端血供的不足，并为皮瓣转移时带来风险。     

Augmentation of acute random pattern skin flap viability in the pig.

Three experiments were conducted to study the effect of ketanserin and LY53857, S2-serotonergic receptor antagonists, on skin blood flow and viability in acute random pattern skin flaps (4 x 10 cm) in the pig. In experiment 1, the dose-response effect of intravenous ketanserin (0, 0.15, 0.25, 0.35, and 0.50 mg/kg) on skin flap capillary blood flow was studied 6 hr after skin flap surgery, using the radioactive microsphere (15 microns) technique and under pentobarbital anesthesia. Significant (P less than 0.05) increase in skin flap blood flow was seen at the dosages of 0.25 and 0.35 mg/kg compared with the saline-treated control. In experiment 2, the effect of five-day intramuscular ketanserin and LY53857 treatment (0.30 mg/kg/day; in divided doses) on skin flap viability was studied. The drug treatments were started two days preoperatively. It was observed that the length of skin flap viability in ketanserin (6.6 +/- 0.2 cm; n = 40 flaps) and LY53857 (6.8 +/- 0.3 cm; n = 40 flaps) treated flaps were significantly (P less than 0.05) higher than the saline-treated control (5.5 +/- 0.1 cm; n = 48 flaps). Ketanserin treatment started 30 min after flap surgery also significantly (P less than 0.05) increased the length of skin flap viability (6.1 +/- 0.1 cm) compared with the control. There was no significant difference in skin viability between ketanserin and LY53857 treated skin flaps. The preceding study on the effect of ketanserin treatment on random pattern skin flap viability was repeated in experiment 3. Again, it was observed that intramuscular ketanserin treatment significantly (P less than 0.05) increased the skin flap viability. It was concluded that ketanserin and LY53857 treatment resulted in significant augmentation of porcine acute random pattern skin flap viability. This is the first experimental evidence to indicate that S2-serotonergic receptors participate in the pathogenesis of skin flap ischemia.     

The redistribution of collagen in expanded pig skin

Silicone tissue expanders were inserted subcutaneously in the buttocks of nine young pigs and gradually inflated to maximum capacity over 5 weeks. On the control side the expanders were left uninflated. Island buttock flaps were then raised, the expanders removed and the flaps spread into the same sites for 10 days. The tissue was harvested. Area measurements and full thickness skin biopsies were taken 10 days after flap inset in order to study the changes in collagen composition and isotypes in the skin layers. Ten days after inset of the flap the expanded skin had a mean 47% increase in surface area, was 9% thinner (from surface to implant), mostly due to thinning of the subcutaneous zone, but was not significantly different in water content, relative to the control skin. The expanded skin had a significant 9.3% increase (p less than 0.01, t test) in collagen content of the dermis. The relative proportions of Types I and III were not significantly changed by skin expansion in either the dermal/epidermal or subcutaneous/capsular zones. It is speculated that tensile factors during expansion stimulate the biosynthetic activity and/or mitotic activity of fibroblasts in the dermis to produce this gain in collagen in the expanded compared with unexpanded tissue.     

Perfusion, viability, and pedicle dependence in acute and delayed rat island skin flaps

Purpose: Although surgical delay phenomenon has been widely investigated, its pathophysiology has not been fully elucidated. Methods: In 25 Spraque-Dawley rats, an 8 x 8 cm2 epigastric skin flap consisting of 4 vertical zones A through D (farthest from vascular pedicle) was outlined. All animals were perfused twice with colored fluorescent microspheres: immediately before and after flap elevation (Acute, n = 10) and before and after pedicle ligation on POD 8 (Delayed, n = 15). Results: After acute flap elevation, peripheral perfusion dropped significantly in zone C (0.29 +/- 0.01 vs. 0.19 +/- 0.04 ml g(-1) min(-1); P < 0.01) and zone D (0.33 +/- 0.09 vs 0.01 +/- 0.01 ml g(-1) min(-1); P < 0.01), while global flap perfusion remained unchanged. Total and regional blood flow did not change in the Delayed group after pedicle ligation. Conclusions: Elevation of a pedicled flap caused significant decrease in distal flap perfusion while maintaining proximal and total flap perfusion. Eight-day delay was adequate to establish sufficient flap perfusion independent of the vascular pedicle.     

Effects of Sodium Nitroprusside and Phenylephrine on Blood Flow in Free Musculocutaneous Flaps during General Anesthesia

Background: Hypoperfusion and necrosis in free flaps used to correct tissue defects remain important clinical problems. The authors studied the effects of two vasoactive drugs, sodium nitroprusside and phenylephrine, which are used frequently in anesthetic practice, on total blood flow and microcirculatory flow in free musculocutaneous flaps during general anesthesia.

Methods: In a porcine model (n = 9) in which clinical conditions for anesthesia and microvascular surgery were simulated, latissimus dorsi free flaps were transferred to the lower extremity. Total blood flow in the flaps was measured using ultrasound flowmetry and microcirculatory flow was measured using laser Doppler flowmetry. The effects of sodium nitroprusside and phenylephrine were studied during local infusion through the feeding artery of the flap and during systemic administration.

Results: Systemic sodium nitroprusside caused a 30% decrease in mean arterial pressure, but cardiac output did not change. The total flow in the flap decreased by 40% (P < 0.01), and microcirculatory flow decreased by 23% in the skin (P < 0.01) and by 30% in the muscle (P < 0.01) of the flap. Sodium nitroprusside infused locally into the flap artery increased the total flap flow by 20% (P < 0.01). Systemic phenylephrine caused a 30% increase in mean arterial pressure, whereas heart rate, cardiac output, and flap blood flow did not change. Local phenylephrine caused a 30% decrease (P < 0.01) in the total flap flow.     

外用前列腺素E1治疗缺血皮瓣的实验研究与临床观察

目的观察外用不同浓度前列腺素E1(PGE1)治疗皮瓣血液循环障碍的疗效. 方法于30只兔背部两侧各制作1条超长比例皮瓣(长6.0 cm、宽2.5 cm).配制质量浓度0.2%、0.4%、0.8%的PGE1乳膏涂抹于皮瓣表面,依次分为A、B、C 3个用药组,每组10条皮瓣.以实验兔自身对侧皮瓣涂抹无PGE1的基础乳膏为对照组,共30条.于用药前、用药后5、10、15、20、30、45、60 min观测皮瓣的血液灌流情况.用药后2 h取皮瓣组织标本,染色后行病理学观察并镜下测量皮瓣内微血管管腔横截面积.于术后3 d测定皮瓣的成活面积,计算其相对成活长度.在此基础上,对7例临床上可能出现坏死的皮瓣外用0.4%PGE1乳膏,观察皮瓣的转归.结果动物实验中可见A、B、C组用药后皮瓣的血流灌注单位明显升高,普遍于用药后30～60 min达到高峰,分别为(8.4±0.5)、(9.1±0.9)、(15.6±1.9)Pu.与对照组(6.1±0.7)～(6.2±0.8)Pu比较,差异有显著性意义(P<0.05);显微镜下见A、B、C组皮瓣内微血管明显扩张;术后A、B组实验兔的皮瓣成活面积和相对成活长度较其他组明显升高(P<0.01).7例患者用药后皮瓣远端全部成活. 结论外用0.2%、0.4%的PGE1软膏可明显改善皮瓣的血液灌流,促进皮瓣成活.     

Evolution of ischemic tissue injury in a random pattern flap: a new mouse model using intravital microscopy

BACKGROUND: Dissection of random pattern flaps may cause microcirculatory dysfunction and ischemia, which jeopardize wound healing due to impaired tissue viability. The aim of this study was to develop an in vivo model that enables continuous monitoring of the interplay between microcirculatory dysfunction, ischemia, and tissue injury by intravital microscopy. MATERIALS AND METHODS: A laterally based random pattern skin flap (15 x 11 mm) including the panniculus carnosus was raised in the back of mice and fixed into a dorsal skinfold chamber (n = 10). Arteriolar blood flow, functional capillary density, number of apoptotic cells, and area of tissue necrosis were analyzed by intravital fluorescence microscopy in the proximal, middle, and distal part of the flap at day 1, 3, 5, and 7 after surgery. Chamber preparations without flap harvesting served as controls (n = 6). RESULTS: At day 1, the distal part of the flap showed a decreased arteriolar blood flow (266 +/- 124 pl/s versus controls: 1418 +/- 351 pl/s; P < 0.05), which resulted in severe alteration of functional capillary density (43 +/- 11 cm/cm2 versus 270 +/- 7 cm/cm2; P < 0.001). The impaired microcirculation was associated with apoptotic cell death (277 +/- 50 cells/mm2 versus 50 +/- 5 cells/mm2; P < 0.05). Microcirculatory dysfunction persisted over 7 days, and, finally, resulted in 49 +/- 3% flap necrosis. CONCLUSIONS: This new model enables repetitive and simultaneous in vivo microscopic evaluation of microvascular hypoperfusion, apoptosis, and tissue necrosis in a random pattern flap. By the use of gene-targeted mice, it bears great potential to analyze distinct mechanisms of flap failure. It further represents an ideal tool to study novel protective strategies, including induction of angiogenesis, heat shock proteins, and HIF-1alpha.