内皮细胞及其对创伤的反应

内皮细胞可合成和释放各种血管反应肽和其它因子。应用营养学、药理学和免疫学疗法来调节手术前后内皮细胞及应,将有益于改善脓毒症、消耗性凝血病、慢性炎症、动脉硬化或高血压等疾病。     

内皮细胞因子及其对损伤的反应

内皮细胞产生糖蛋白粘附分子,促进了内皮细胞与白细胞的结合,有利于炎性细胞的迁移。内皮细胞产生释放的促凝和抗凝因子、内皮细胞源性舒张因子以及内皮细胞源性收缩因子(内皮素)对局部的血凝机理以及血管功能有着重要的作用。精氨酸、ω-3脂肪酸等营养素可调节内皮细胞的功能。创伤和某些病理状态可导致内皮细胞功能表达不当,从而表现出一系列病理现象。     

严重创伤后的全身性反应及救治策略

创伤是临床常见的多发病，发病率呈上升趋势。随着现代社会经济与科学技术的快速发展，交通事故、工程建设和自然灾害等各类创伤的发病率上升。现代创伤不仅数量七逐年增多，而儿疾病的性质也更严重复杂，呈现致伤因子高能量、瞬间作用于人体，造成多部位和多脏器损伤的特点，从而使全身变化呈进行性加重的发展趋势。可使免疫调节网络失控，细胞内外环境完全紊乱，代谢功能障碍，容易发展“全身炎症反应综合征”（systemic inflammatory response syndrome，SIRS）和多器官功能障碍综合征（multiple organ dysfunction syndrome MODS）。需要弄清创伤发生、发展及转归的详细机制，探索出有效的创伤救治方法。     

严重创伤病人感染危险因素的病例对照研究

目的：探讨创伤后感染发生的危险因素。方法：观察１２对以ＩＳＳ和年龄配对创伤后发生和不发生感染的病人。两组的ＡＰＡＣＨＥⅡ评分、总淋巴细胞计数、住ＩＣＵ天数。结果：用抗生素天数、单核细胞ＤＲ抗原表达率等指标差别非常显著。结论：用这５项指标建立判别函数，可对创伤病人进行感染危险性预测。     

创伤后感染

战伤感染发生率甚高。据1979年至1984年我西南边境自卫反击战资料统计,火器伤的化脓性感染率在20％～30％,个别报告高达40％～60％。感染也是存活伤员的主要威胁。后期死亡的伤员,2／3甚至3／4的死因与严重感染有关。早期积极防治感染,对提高创伤救治成功率、降低死亡率和伤残率具有特别重要的意义。     

血管内皮细胞的保护

血管内皮细胞（ＥＣ）具有多种重要功能。内皮损伤在创力、成人呼吸窘迫综合征、脓因症、多器官功能衰竭等疾病过程中起关键作用。ＥＣ的保护是预防的治疗管些疾病的措施之一。本文综述了抗氧化剂、蛋白酶及脂酶抑制剂、锌、硒及某些中药等对ＥＣ的保护作用。     

全身性感染发病机制及治疗的研究进展

全身性感染是指微生物人侵机体感染后所致的全身性炎症反应综合征。病原微生物的病原相关分子模式(pathogen-associated moleculm pattern，PAMP)通过与免疫细胞的Toll样受体相互作用，激活跨膜信号转导过程，调控炎症介质基因表达，导致免疫炎症反应失控、促炎／抗炎反应不平衡，进而使全身性感染及其后续症发生、发展。Toll样受体的多态性与全身性感染发生发展相关。活化型重组人蛋白C、早期支持治疗等辅助治疗有助于降低严重感染及其后续症的死亡率，但以PAMP识别受体、炎症介质为靶向将赋予全身性感染的发病机制和治疗新启迪。     

创伤后肠源性感染的防治

创伤后肠源性感染的防治重点在于维护肠道正常的生理功能(包括肠粘膜屏障功能、肠道正常菌群的生态平衡和肠道免疫功能),采取有效措施调理机体免疫功能,同时阻止或限制过强的炎症反应。     

细菌通用引物PCR快速诊断全身性感染的研究

目的:建立PCR直接检测临床血标本中病原菌的方法,探索其快速诊断全身性感染(sepsis)的应用价值.方法:利用16S rRNA基因的高度保守性,设计并合成细菌的通用引物;采用合成的引物扩增标准菌株及全身性感染病人的血样本,并与血培养进行对照.结果:通用引物PCR可检出0.005pg的大肠埃希菌标准菌株DNA;临床分离的大肠埃希菌、金黄色葡萄球菌PCR扩增产物于255bp处均可见清晰电泳条带,正常人无菌血白细胞及白色念珠菌DNA扩增产物均未见电泳条带出现;PCR可快速地检出血液中多种病原菌DNA,所检的8例病人中4例阳性(50%).结论:165 rRNA基因为基础的PCR,可直接用于临床血标本病原菌的检测,初步实验显示其具有特异、快速等优点,敏感性较血培养有增高趋势,有利于重症急性胰腺炎及其他外科危重病Sepsis的早期诊断.     

Predictors of blinding or serious eye injury in blunt trauma.

Multivariate analysis was used to identify factors predicting injury and visual outcome in 94 blunt trauma patients evaluated for eye injuries among 6700 admissions to a level I trauma center over a 29-month period. Patients with penetrating eye injuries were excluded from this review. Eye injury was detected in 93% or 87 of the patients evaluated. Seven percent of eye injuries resulted in blindness, 22% were serious (visual acuity between 20/40 and 20/200 or eye injury requiring surgery), and 71% were temporary (final visual acuity of 20/40 or better). The presence of an afferent pupillary defect or a nonreactive pupil was the most important factor in predicting the severity of eye injury (p = 0.0023), followed by facial fractures (p = 0.0084), and no eye opening or eye opening to pain within the Glasgow Coma Scale (p = 0.02). Eye injury is an infrequent complication of blunt trauma. Appropriate consultation for evaluation of this problem can be obtained based on findings from the initial history and screening physical examination.     

The mechanism of the reduction of protein catabolism following trauma and during sepsis using xylitol

Total parenteral nutrition (TPN) after trauma and sepsis has two major goals. One is the reduction of enhanced protein catabolism; the second is the avoidance of enhancement of whole-body glucose turnover. Glucose and xylitol differ in their quantitative utilization rate after trauma and sepsis. Maximal glucose utilization is reduced during such states, while the utilization of xylitol is more than doubled. In order to investigate whether these differences are associated with beneficial effects with regard to whole-body glucose turnover rate of gluconeogenesis and protein sparing, we conducted two studies using animal models and two clinical studies. METHODS. For the determination of glucose and protein turnover, radioactive and stable isotope techniques were applied. In an animal model a primed constant infusion of 3-H-6-glucose, 14-C-1-alanine and 13-C-3-alanine and 14-C-U-acetate was used to determine total glucose appearance, gluconeogenesis from 3-C-precursors and alanine flux. In the human studies hepatic glucose production was determined by using a primed constant infusion of 6.6-D-2-glucose and urea synthesis rate was determined by a primed constant infusion of 2-N-15-urea. RESULTS. In the first rat model we were able to show that hypocaloric xylitol compared to glucose significantly reduced whole-body glucose turnover from 1741 +/- 232 mumol/h during glucose infusion to 449 +/- 49 mumol/h during xylitol infusion and gluconeogenesis from C-3 carbons form 382 +/- 24 mumol/h during glucose infusion to 155 +/- 39 mumol/h during xylitol infusion after a burn trauma. In a second septic rat model the exchange of glucose calories by xylitol in a proportion of 1:1 was associated with a significantly ameliorated N-balance from +144 +/- 90 mgN/kg body weight per day during glucose infusion to +699 +/- 80 mgN/kg body weight per day during glucose-xylitol infusion and a reduced 3-methyl-histidine excretion from 7.14 +/- 0.61 mumol/kg body wt. per day during glucose infusion to 4.10 +/- 0.56 mumol/kg per day during glucose-xylitol infusion, respectively. In two studies with surgical intensive care patients we were able to confirm the nitrogen-sparing properties of xylitol infusion, together with amino acids during hypocaloric feeding or during TPN with a glucose/xylitol mixture in a proportion of 1:1. From a basal urea production rate of 9.2 +/- 1.6 mumol/kg min. xylitol led to a significant reduction with 6.4 +/- 1.5 mumol/kg per min. Hepatic glucose production was significantly reduced during xylitol infusion from basal 4.8 +/- 0.6 mg/kg per min to 3.1 +/- 0.7 mg/kg per min, respectively. Equicaloric glucose in a dosage of 3 g/kg per day had no effect. During TPN glucose/xylitol, in a proportion of 1:1 at a total dosage of 0.24 g/kg per h, significantly reduced whole-body glucose turnover, endogenous glucose production and lactate concentrations compared to an isocaloric glucose infusion. DISCUSSION. In animal as well as in human studies hypocaloric xylitol as well as a glucose-xylitol mixture were more efficient in preserving body protein than glucose alone. Whole-body glucose turnover was significantly reduced during hypocaloric xylitol or glucose-xylitol infusion compared to isocaloric glucose infusion. During the acute phase after trauma we therefore recommend a carbohydrate supplementation of 3 g/kg body wt. per day using xylitol. During long-term TPN, a glucose-xylitol mixture in a proportion of 1:1 in a dosage of 3 g/kg body wt. per day each is recommended as energy source, together with amino acids and, if necessary, lipids.     

The metabolic response to trauma and sepsis

The metabolic response of the body to trauma and sepsis is the summed response of the organs. Net catabolism of the muscles of ambulation is particularly important in providing the other organs with a source of amino acids for protein synthesis and, therefore, anabolism. This net catabolism of muscle is based upon decreased physical activity, the net effects of the neuroendocrine system, and the consequences of local amino acid concentration changes within muscle, particularly of leucine. Secondary to these changes, previously healthy humans sustaining acute short-term trauma of fairly major degree do not require exogenous supplies of amino acid even though the patient has a short-term negative nitrogen balance. In contrast, the septic patient has, in addition to the preceding changes, activation of phagocytosis with release of phagocytic factors that mobilize white cells, increase body temperature, and further modulate the metabolism of muscle and probably all other organs. Since these changes are induced by phagocytosis, which may be activated by retained dead tissues of all kinds, the basic attributes of the septic state may be activated in the absence of bacteria. The retained dead tissue makes bacterial growth much more likely. The septic state, therefore, has as its hallmark all of the changes of the trauma state, plus a prolonged enhanced catabolism of all amino acids, which leads to protein malnutrition with its overt manifestation of multiple systems organ failure. These patients require calories only 10 to 50% in excess of the requirement of normal humans, but a great increase in amino acid intake (up to 2.5% to 3 g/kg per day). This support will purchase more time in which to treat the underlying sepsis.     

Serial changes in leukocyte deformability and whole blood rheology in patients with sepsis or trauma

BACKGROUND: The objective of this study was to investigate serial changes in leukocyte deformability and rheologic properties of whole blood in patients with sepsis or trauma. METHODS: Seventeen sepsis patients and 22 trauma patients were enrolled. Leukocyte deformability and rheologic properties of whole blood were determined with the use of a microchannel array etched on a single-crystal silicon tip, simulating the microvasculature. The number of obstructed microchannels (NOM) was used as a measure of leukocyte deformability. Transit time (TT), i.e., the time taken for 100 microL of whole blood to pass through the microchannel array was also used as rheologic measure. Oxidative activity and F-actin content of neutrophils was measured in patients with sepsis. RESULTS: NOM and TT significantly increased in patients when sepsis was diagnosed. In survivors, NOM and TT decreased at the time of recovery from sepsis, but in non-survivors values remained high. Oxidative activity and F-actin content of neutrophils increased significantly as leukocyte deformability decreased. In patients with severe trauma, NOM and TT increased after injury and decreased by the time of recovery from the critical stage. CONCLUSION: We conclude that leukocyte deformability decreases in patients with sepsis or severe trauma and that this change negatively affects rheologic properties of whole blood.     

Interest in several surgeries for serious abdominal trauma

Abbreviated laparotomy and planned reoperation(s) is a new concept in severely injured patients with multivisceral failure by hemorrhagic shock, coagulopathy and hypothermia. The aim of an abbreviated laparotomy is to control hemorrhage, prevent digestive contamination and close the abdominal wall without tension. After a delay for reanimation during 24 to 96 hours, discovery of unknown lesions and anatomic reconstruction will be possible through planned reoperation in better conditions. Emergency reoperation for hemorrhage and abdominal hyperpression severely worsens prognosis.     

创伤后脓毒症的外科控制

创伤是较常见的死亡原因。创伤后脓毒症引起的病死率居高不下。要提高创伤后脓毒症的诊治水平,必须明确有关创伤后脓毒症的准确定义以及诊断标准。合理的外科处理能显著降低创伤后脓毒症的发生率,措施包括选择合适的手术时机、清创及引流,另外合理使用抗生素以及控制院内感染亦很重要。本文综述近年来在创伤后脓毒症的外科控制领域的新观念及发展趋势。     

Host resistance in sepsis and trauma.

Host resistance to infection was measured by the in vivo response to 5 delayed hypersensitivity antigens and to sensitivity and challenge by dinitrochlorobenzene (DNCB) in 55 seriously ill or injured patients and in 50 preoperative patients. A close correlation between infections, septicemia, death related to infection and anergy was found in the postoperative and post injury patients and was predictive of these complications in the patients studied preoperatively. Decreased body cell mass was noted in both the anergic and non-anergic patients which was consistent with protein-calorie malnutrition but the two groups were not significantly different. A serum factor which inhibited cellular immunity in vitro was found in 4 patients. This factor disappeared in the two patients who recovered. The study suggests the therapeutic value of the in vivo measurement of delayed hypersensitivity in seriously ill and especially preoperative patients in whom specific or non-specific stimulation of cell mediated immunity might alter the risk of infection.