高压氧对大鼠脑外伤后脑神经功能与病理变化的影响(论著)

目的：观察高压氧（ＨＢＯ）对脑外伤后脑神经功能与病理变化的影响。方法：２４只ＳＤ大鼠随机分为正常组、假手术组、ＨＢＯ组和外伤对照组。建立大鼠侧方液压颅脑损伤模型，观察脑神经功能、脑组织含水量、脑组织损伤面积等病理变化。结果：ＨＢＯ组与外伤对照组相比，神经功能异常较轻、脑组织含水量和损伤面积较小（Ｐ＜０．０５），同时脑组织病理改变较轻。结论：ＨＢＯ对脑外伤后的脑神经组织和功能有明显保护作用，其机理考虑与纠正脑缺氧，恢复能量供应，减轻脑水肿和减少脑组织病变等有关。     

大鼠氧惊厥时脑内μ-阿片受体的变化

目的　探讨大鼠氧惊厥时脑内 μ-阿片受体的变化。方法　用 [3H]-羟甲芬太尼作为特异性标记配体 ,采用放射配体受体结合实验 (radioligand binding assay,RBA) ,测定在几种不同气体及压力的暴露条件下 ,大鼠脑内 μ-阿片受体的 k D值和 Bmax值的变化。结果　大鼠氧惊厥前 ,脑内 μ-阿片受体的 k D值即有增大趋势 (但 P>0 .0 5 ) ,Bmax值减小 (P<0 .0 1) ;氧惊厥时 k D值进一步升高 (P<0 .0 1) ,Bmax值反而增大 (P<0 .0 1)。结论　结果提示 :(1)氧惊厥发作中 ,μ-阿片受体的数量增多 ,而其结合活性降低。(2 )在高压氧 (HBO)暴露中 ,μ-阿片受体参与了氧惊厥的过程     

高气压暴露对大鼠血浆内皮素-1含量、血清一氧化氮含量、一氧化氮合酶活性的影响

目的 探讨高气压暴露对大鼠血浆内皮素-1(endothelin-1,ET-1)含量、血清一氧化氮(nitric oxide,NO)含量、一氧化氮合酶(nitric oxide synthase,NOS)活性的影响.方法 40只SD大鼠随机分为5组.A组为对照组,B组0.7 MPa空气暴露后缓慢减压,C组0.7 MPa空气暴露后快速减压,D组0.147 MPa纯氧暴露后减压,E组0.250 MPa纯氧暴露后减压.各组暴露时间均为60 min.采用放射免疫方法测定血浆ET-1含量,硝酸还原酶法测定血清NO含量,比色法测定血清NOS活性.结果 与对照组相比,安全减压组和高压氧组的血浆ET-1含量明显升高(P<0.05),原因可能与高分压氧有关(PO2=0.147 MPa/0.250 MPa);快速减压组血清NO含量、NOS活性明显升高(P<0.05),与血浆ET-1含量升高的3个组相比,血清NO、NOS升高得更为显著(P<0.01).结论 NO与ET-1在机体对高气压暴露的反应中呈拮抗关系.高气压与高压氧暴露导致血浆ET-1的释放增加,但快速减压刺激血管内皮细胞产生更多的NO,这种机制可能是通过提高血浆中的NOS活性实现的,这个现象可能是血管内皮系统对血管内气泡产生的应激性反应之一.     

高压氧对皮质下动脉硬化性脑病的疗效观察

目的：总结不同方法治疗皮质下动脉硬化性脑病（ＳＡＥ）的疗效。方法：６７例ＳＡＥ患者，其中ＨＢＯ组３５例，药物组３２例，对治疗前、后患者的智能状态、大脑局部血流量和血液流变学指标进行比较。结果：高压氧（ＨＢＯ）组各疗程治疗后患者智能均明显改善，主要表现为记忆力和计算力改善，大脑灰质血流量降低，白质血流量显著增加，全血多切变粘度下降，红细胞变形能力增强；药物组各疗程治疗后患者智能无明显变化，大脑灰质血流增加，白质血流无明显变化，血浆比粘度和全血低切变粘度下降。两组１个疗程临床有效率相差非常显著。结论：ＨＢＯ能够改善ＳＡＥ患者的智能状态，效果优于药物治疗。     

高压氧对家兔随意皮瓣血管内皮生长因子和缝隙连接蛋白的影响

目的 探讨高压氧对家兔随意皮瓣毛细血管增殖作用的机制.方法 建立家兔背部随意皮瓣模型,予高压氧治疗,观察第3天和第7天时对照组和高压氧组皮瓣中毛细血管密度及血管内皮细胞生长因子(VEGF)、缝隙连接蛋白(CX43)的含量变化情况.结果 高乐氧组皮瓣毛细血管密度(第3天11.63±2.94,第7天13.84±3.49)明显高于对照组(第3天9.13±2.00.第7天10.51±3.01)(第3天时P<0.05,第7天时P<0.01);第3天和第7天时高压氧组皮瓣VEGF(第3天5.50±1.68,第7天5.81±1.64)表达明显高于对照组(第3天4.55±1.06,第7天4.63±1.24)(分别为P<0.01);高压氧组皮瓣CX43(第3天4.08±0.88,第7天4.60±0.97)表达明显高于对照组(第3天3.28±0.68,第7天3.60±1.01)(第3天时P<0.01,第7天时P<0.05).结论 高压氧治疗促进家兔随意皮瓣毛细血管增殖的作用机制之一可能是通过增加皮瓣组织中VEGF、CX43的表达而促进新生毛细血管形成.     

人在海拔5 380 m高原进行体力活动时耗氧量及血氧饱和度的观察

目的探讨高海拔低氧环境影响人体劳动能力的因素,为提高高原劳动功效提供理论依据. 方法受试者坐于踏车功量机上,以60 r/m连续蹬车,每3 min递增25 W,蹬车至力竭时停止,用心电图机记录每个负荷末期5 s的心率(HR),用O2-CO2气体测定仪及掌式血氧仪分析每个负荷最后30 min的O2和CO2含量及动脉血氧饱和度(SaO2),计算耗氧量(VO2)和氧脉搏(VO2/HR). 结果 HR在100～170 次/min时,VO2随HR的增加而呈线性增加(=-0.218 4+0.007 7x,r=0.975 9,P<0.01);HR为100～130次/min时,VO2/HR也随HR增加而增加;HR增加到140～170次/min时,VO2/HR不但不增加反而减少,SaO2亦随VO2的增加而减少. 结论高原低氧环境增加了人体生理负荷,致使人体在高原的劳动能力下降.     

高压氧对脑白质疏松大鼠的神经保护作用

目的探讨高压氧对脑白质疏松大鼠的行为学、海马结构及神经元影响。方法采用双侧颈总动脉结扎法制作缺血缺氧脑白质疏松模型,术后2 w脑白质疏松形成。第15天起给予2.0ATA的压力治疗1 h/d,共14 d。定位航行实验、足迹实验观察大鼠行为学变化,HE染色观察大鼠神经元形态学变化,TUNEL法观察凋亡神经元情况。结果与假手术组相比,手术组及高压氧治疗组大鼠认知功能明显减弱,神经元数量减少,排列疏松,胞核固缩,TUNEL阳性细胞增多;与手术组比较,高压氧组认知功能有所改善,神经元数量多且排列整齐。TUNEL法测高压氧组神经元凋亡情况改善。结论高压氧可改善脑白质疏松大鼠海马结构和神经元凋亡情况,且有助于其认知功能的恢复。     

Intra-operative oxygen delivery in infusion volume-optimized patients undergoing laparoscopic colorectal surgery within an enhanced recovery programme: the effect of different analgesic modalities

Aim Patients undergoing major open surgery who have an indexed oxygen delivery (DO₂I) > 600 ml/min/m² have been shown to have a lower incidence of morbidity and mortality compared with those whose DO₂I is below this level. Laparoscopy and Trendelenburg positioning cause a reduction in DO₂I. We aimed to quantify the effect of the type of analgesia on DO₂I and to correlate the DO₂I achieved with the incidence of anastomotic leakage in patients undergoing laparoscopic surgery. Method Following ethical approval, patients were randomized to receive spinal anaesthesia (Group S), epidural analgesia (Group E) or intravenous morphine (Group P) followed by postoperative patient‐controlled analgesia (PCA). In addition to standard monitoring, oesophageal Doppler monitoring of the stroke volume allowed directed intravenous fluid therapy. The mean DO₂I was compared with the anastomotic leakage rate. Results Seventy‐five patients were recruited (Group S, 27; Group E, 23; Group P, 25). The mean (range) DO₂I for all patients was 490 (230‐750) ml/min/m². The analgesic modality had no effect on DO₂I. Of the 18 patients with a DO₂I of < 400 ml/min/m², four (22%) developed anastomotic leakage compared with one (%) of the 57 patients with a DO₂I of > 400 ml/min/m² (P = 0.01). Conclusion The analgesic modality used had no effect on the DO₂I achieved. Anastomotic leakage was significantly higher in patients with a DO₂I of < 400 ml/min/m². A further study assessing the outcome after raising the DO₂I with inotropes is required.     

High frequency percussive ventilation and low FiO(2)

Background

High-frequency percussive ventilation (HFPV) is an effective rescue therapy in ventilated patients with acute lung injury. High levels of inspired oxygen (FiO₂) are toxic to the lungs. The objective of this study was to review a low FiO₂ (0.25)/HFPV protocol as a protective strategy in burn patients receiving mechanical ventilation greater than 10 days.

Methods

A single-center, retrospective study in burn patients between December 2002 and May 2005 at the LAC + USC Burn Center. Demographic and physiologic data were recorded from time of admission to extubation, 4 weeks, or death.

Results

32 subjects were included in this study, 1 patient failed the protocol. 23 of 32 (72%) patients were men and mean age was 46 ± 15 years. Average TBSA burn was 30 ± 20 with 9 of 32 (28%) having >40% TBSA involved. Average burn index was 76 ± 21. 22 of 32 (69%) had inhalation injury and 23 of 32 (72%) had significant comorbidities. Average ventilator parameters included ventilator days 24 ± 12, FiO₂ 0.28 ± 0.03, PaO₂ 107 ± 15 Torr, PaCO₂ 42 ± 4 Torr, and PaO₂/FiO₂ ratio 395 ± 69. 16 of 32 (50%) patients developed pneumonia and 9 of 32 (28%) died. No patient developed ARDS, barotrauma, or died from respiratory failure. There was no association between inhalation injury and mortality in this group of patients.

Conclusion

A low FiO₂/HFPV protocol is a safe and effective way to ventilate critically ill burn patients. Reducing the oxidative stress of high inspired oxygen levels may improve outcome.     

依达拉奉联合高压氧治疗颅脑外伤的临床效果

目的通过观察脑外伤后患者炎性因子、细胞免疫以及神经功能指标的变化探讨颅脑外伤患者联合应用依达拉奉以及高压氧治疗的临床效果。方法选取2015年3月~2017年3月在我院收治的颅脑外伤患者90例,随机分为对照组和研究组,对照组应用依达拉奉治疗,研究组联合应用高压氧治疗。比较治疗前后的GCS、ADL评分;IL-6、CRP、TNF-α;CD4~+、CD8~+、CD4~+/CD8~+的差异。结果治疗前两组患者的GCS及ADL评分无显著差异(P0.05),治疗后2周及4周研究组显著高于对照组(P0.05);治疗前两组患者的IL-6、CRP、TNF-α无显著差异(P0.05),治疗后2周及4周研究组IL-6、CRP、TNF-α显著低于对照组(P0.05);治疗前两组患者的CD4~+、CD8~+、CD4~+/CD8~+无显著差异(P0.05),治疗后2周及4周研究组CD4~+、CD8~+、CD4~+/CD8~+显著高于对照组(P0.05)。结论依达拉奉联合高压氧治疗颅脑外伤患者,有利于降低炎性因子水平,提高治疗效果。