允许性高碳酸血症对老年糖尿病患者术后认知功能的影响

目的 探讨允许性高碳酸血症对老年糖尿病患者术后认知功能的影响。
方法 选择全麻下行腹腔镜上腹部手术的老年糖尿病患者60例，将患者随机分为两组：允许性高碳酸血症通气糖尿病组（DH组）和常规通气糖尿病组（DR组），每组30例。另选择全麻下行腹腔镜上腹部手术非糖尿病老年患者60例，将患者随机分为两组：允许性高碳酸血症通气非糖尿病组（NH组）和常规通气非糖尿病组（NR组），每组30例。麻醉诱导后行机械通气，调控呼吸参数使DH组和NH组维持PaCO₂ 45～65 mmHg，DR组和NR组维持PaCO₂ 35～45 mmHg。记录气腹前5 min及气腹后5、15、30 min的P_ETCO₂，并采集以上时点桡动脉、颈内静脉血样行血气分析，记录pH值、PaCO₂，计算动脉-颈内静脉血氧含量差（Da-jvO₂）和脑氧摄取率（CERO₂）。检测麻醉诱导前及术后3 d的血清S100β蛋白浓度。记录术前1 d和术后1、3、7 d的蒙特利尔认知评估量表（MoCA）评分和术后认知功能障碍（POCD）的发生情况。
结果与气腹前5 min比较，四组气腹后5、15、30 min时P_ETCO₂和PaCO₂明显升高，pH值、Da-jvO₂和CERO₂明显降低（P<0.05）。与麻醉诱导前比较，四组术后3 d血清S100β蛋白浓度均明显升高（P<0.05）。与术前1 d比较，四组术后1、3 d MoCA评分均明显降低（P<0.05）。与DR组比较，DH组气腹前5 min及气腹后5、15、30 min时P_ETCO₂明显升高，pH值、Da-jvO₂和CERO₂明显降低，术后3 d血清S100β蛋白浓度明显降低，术后1、3 d MoCA评分明显升高，POCD发生率明显降低（P<0.05）。与NR组比较，NH组气腹前5 min及气腹后5、15、30 min时P_ETCO₂明显升高，pH值、Da-jvO₂和CERO₂明显降低，术后3 d血清S100β蛋白浓度明显降低，术后1、3 d MoCA评分明显升高，POCD发生率明显降低（P<0.05）。与NH组比较，DH组气腹前5 min及气腹后5、15、30 min时Da-jvO₂和CERO₂明显升高，术后3 d血清S100β蛋白浓度明显升高，术后1、3 d MoCA评分明显降低（P<0.05）。
结论允许性高碳酸血症可改善老年糖尿病患者术中脑氧代谢，降低术后血清S100β蛋白浓度，降低术后认知功能障碍的发生率。     

脑氧饱和度监测下控制性降压对老年高血压患者术后谵妄的影响

目的 探讨脑氧饱和度(rSO₂)监测下控制性降压对老年高血压患者术后谵妄（POD）的影响。方法 择期全麻下行鼻泪道手术的老年高血压患者110例,男53例,女57例,年龄65~85岁,ASA Ⅱ或Ⅲ级,高血压Ⅰ或Ⅱ级,采用随机数字表法分为两组：rSO₂监测组（S组）和对照组（C组）,每组55例。两组均采用乌拉地尔联合艾司洛尔控制性降压,维持MAP≥基础值的70%,且MAP≥55 mmHg;当S组rSO₂<基础值的80%或rSO₂最低值<基础值的50%,并且持续时间大于10 s,则逐步提升血压直至rSO₂恢复至≥基础值的80%或绝对值＞50%。C组rSO₂监护仪施行遮盖处理。记录入室后吸氧5 min（T0）、控制性降压15 min（T1）、30 min（T2）、控制性降压结束后5 min（T3）、拔管后10 min（T4）的HR、MAP、rSO₂;记录rSO₂基础值、术中最低值及较基础值下降的最大百分比;术后1、2、3 d采用谵妄评定方法 中文修订版（CAM-CR量表）对患者进行POD评估。结果 与T0时比较,T1—T2时两组MAP明显下降（P<0.05）,C组rSO₂明显下降（P<0.05）,T3—T4时逐渐回升至术前水平。T1—T2时S组rSO₂明显高于C组（P<0.05）,术中rSO₂最低值明显高于C组（P<0.05）,rSO₂较基础值下降的最大百分比明显低于C组（P<0.05）。术后1 d S组POD发生率明显低于C组（P<0.05）。结论 rSO₂监测下控制性降压能减少老年高血压患者鼻泪道手术后谵妄的发生,提高围术期安全性。     

基于肺超声评分评估压力控制容量保证通气模式对腹腔镜胃癌根治术患者肺通气的影响

目的 探讨基于肺超声评分（LUS）评估压力控制容量保证通气（PCV-VG）模式与容量控制通气（VCV）模式对腹腔镜胃癌根治术患者通气功能及术后肺部并发症（PPCs）的影响。
方法 选择择期行腹腔镜胃癌根治术患者80例,男67例,女13例,年龄45～75岁,ASA Ⅱ或Ⅲ级。采用随机数字表法将患者分为两组：VCV通气模式组（V组）和PCV-VG通气模式组（P组）,每组40例。所有患者常规麻醉诱导,采用保护性通气策略：VT 7 ml/kg,呼气末正压（PEEP）5 cmH₂O,FiO₂ 40%。采用床旁肺超声评估患者双侧肺部共12个区域的LUS。记录入室时（T0）、麻醉诱导气管插管后20 min（T1）、建立人工气腹后30 min（T2）、气管导管拔除后15 min（T5）的LUS评分。行血气分析记录PaO₂、PaCO₂。记录T1、T2、气腹后1 h（T3）、手术结束时（T4）的气道峰压（Ppeak）、平台压（Pplat）、气道平均压（Pmean）、动态肺顺应性（Cdyn）、VT。记录术后3、7 d内PPCs的发生情况。
结果 与T0时比较,T1、T2、T5时P组整体、前部、外侧、后部、左肺、右肺、上肺及下肺LUS明显降低（P＜0.05）;T2时V组整体及部分区域（后部、下肺及右肺）LUS明显降低,T5时V组整体及部分区域（外侧、下肺及左肺）LUS明显升高（P＜0.05）。与V组比较,T1、T2、T5时P组整体及各区域LUS评分均明显降低,PaO₂明显升高,T1、T5时PaCO₂明显降低,T1—T4时Ppeak明显降低,Pmean、Cdyn明显升高,T4时Pplat明显降低（P＜0.05）。术后3 d内P组PPCs发生率明显低于V组［4例（10%）vs 11例（28%）,P＜0.05］。
结论 LUS能够显示手术期间PCV-VG模式和VCV模式下肺通气的非均匀性和体位性变化。肺保护性通气策略下,PCV-VG模式明显改善了腹腔镜胃癌根治术患者术中肺通气及氧合功能。     

肺动态顺应性指导个体化呼气末正压通气对老年患者腹腔镜结直肠癌术中肺功能的影响

目的 观察肺动态顺应性（Cdyn）指导个体化呼气末正压通气（PEEP）对老年患者腹腔镜结直肠癌术中肺功能的影响。
方法选择择期行腹腔镜结直肠癌根治术的老年患者68例，男37例，女31例，年龄65～79岁，BMI<30 kg/m²，ASA Ⅱ或Ⅲ级。采用随机数字表法将患者分为两组：个体化PEEP组（P组）和对照组（C组），每组34例。P组在插管完成即刻、气腹-屈氏体位建立即刻、气腹结束即刻行肺复张及PEEP滴定试验，C组设置固定PEEP 5 cmH₂O。记录P组3次滴定时最佳PEEP和实际V_T。记录气管插管完成后10 min（T₁）、气腹-屈氏体位建立后10 min（T₂）、60 min（T₃）、手术结束拔管前（T₄）PaO₂、PaCO₂、P_ETCO₂，计算氧合指数（OI）、死腔/潮气量比值（Vd/V_T）、肺泡-动脉血氧分压差（A-aDO₂）、驱动压和Cdyn。采用ELISA法测定麻醉诱导前（T₀）、拔管后10 min（T₅）的白细胞介素-8（IL-8）、肿瘤坏死因子-α（TNF-α）、肺Clara细胞分泌蛋白（CC16）及肺泡表面活性物质-D（SP-D）的浓度。记录术后肺部并发症（PPCs）的发生情况。
结果 P组滴定最佳PEEP的中位数为4 cmH₂O。与C组比较，P组T₄时PaO₂、OI明显升高，T₁、T₃、T₄时Cdyn明显升高，T₁—T₄时驱动压明显降低，T₅时CC16血清浓度明显降低（P<0.05）。两组T₁—T₄时PaCO₂、P_ETCO₂、A-aDO₂、Vd/V_T差异无统计学意义。两组术后3 d均未发生严重PPCs。
结论 在老年患者腹腔镜结直肠癌根治术中，采用压力控制通气下肺动态顺应性指导个体化PEEP的肺保护通气策略，可提高患者术中肺动态顺应性，降低驱动压，改善手术结束时氧合，降低术后CC16血清浓度，改善术中肺功能。     

不同通气模式对腹腔镜下Trendelenburg体位患者肺通气的影响

目的 采用电阻抗断层成像(EIT)技术观察容量控制通气(VCV)和压力控制容量保证通气(PCV-VG)模式对腹腔镜下Trendelenburg体位患者全麻术中肺通气的影响。方法 择期全麻下行腹腔镜下Trendelenburg体位妇科手术患者60例,年龄40～65岁,BMI 18～30 kg/m²,ASA Ⅰ或Ⅱ级,采用随机数字表法将患者分为两组：VCV模式组（V组）和PCV-VG模式组（P组）,每组30例。V组术中采用VCV模式,P组采用PCV-VG模式。记录入室后(T0)、插管后5 min(T1)、更改体位（由平卧位更改为Trendelenburg体位）后即刻(T2)、更改体位后30 min(T3)、更改体位后60 min(T4)、更改体位后120 min(T5)、改平卧位(T6)时的MAP、HR、通气中心(CoV)、依赖静止区(DSS)、非依赖静止区(NSS)的面积百分比。记录T1、T3—T5时气道峰压（Ppeak）、pH、PaO₂、PaCO₂、氧合指数（OI）。记录术后7 d内肺部感染、呼吸衰竭等肺部并发症发生情况。结果 T0—T6时两组MAP、HR差异无统计学意义。与V组比较,T3—T6时CoV面积百分比明显升高,DSS面积百分比明显降低（P<0.05）,T3—T5时Ppeak明显降低（P<0.05）,T4、T5时PaO₂、OI明显升高（P<0.05）。两组术后7 d内均无肺部并发症。结论 PCV-VG通气模式可明显改善腹腔镜下Trendelenburg体位患者术中肺通气及肺氧合功能。     

不同流速经鼻湿化快速充气通气联合无创通气对肥胖患者全麻诱导期胃进气的影响

目的 通过胃窦超声检查评估不同流速经鼻湿化快速充气通气（THRIVE）联合无创通气（NIV）在全麻诱导时对肥胖患者胃进气的影响。
方法 选择择期全麻手术患者72例,男29例,女43例,年龄18～64岁,BMI 30.0～39.9 kg/m²,ASA Ⅰ或Ⅱ级。随机分为三组：H30组、H50组、H70组,每组24例。三组均行THRIVE 30 L/min预给氧5 min后行全麻诱导。全麻诱导后三组分别接受相应氧流量大小（30、50、70 L/min,FiO₂ 100%）的THRIVE联合NIV（10 cmH₂O）行压力控制给氧。气管插管期,各组继续行对应流速THRIVE以提供窒息氧合。入室时以及诱导通气结束时,采用超声监测患者仰卧位胃窦部进气情况,超声图像出现“彗尾征”则定义为胃进气阳性（GI⁺）。记录全麻诱导期GI⁺的发生情况;记录入室时以及诱导通气结束时的胃窦部横截面积（CSA）;记录插管过程中SpO₂最低值以及诱导通气结束时PaO₂、PaCO₂、P_ETCO₂等呼吸参数;记录术后恶心呕吐、反流误吸、鼻咽部不适和气压伤等不良事件的发生情况。
结果 全麻诱导期H70组GI⁺发生率明显高于H30组、H50组（P<0.05）。与入室时比较,诱导通气结束时H70组胃窦部CSA明显增大（P<0.05）。诱导通气结束时H70组CSA明显大于与H30组、H50组（P<0.05）。插管过程中H50组、H70组SpO₂最低值明显高于H30组（P<0.05）;诱导通气结束时H50组、H70组PaO₂明显高于H30组,PaCO₂明显低于H30组（P<0.05）。三组恶心呕吐发生率差异无统计学意义。三组均无一例反流误吸、鼻咽部不适和气压伤。
结论 THRIVE 50 L/min联合NIV 10 cmH₂O压控给氧能为肥胖患者全麻诱导期提供较好的氧合,且明显降低胃进气发生率。     

食管癌根治术中肾脏氧饱和度与术后肾功能异常的相关性

目的 探讨食管癌根治术中肾脏区域组织氧饱和度（rSO₂）与术后肾功能异常的相关性。
方法 选择拟行食管癌根治术的患者116例,男93例,女23例,年龄18～64岁,BMI＜24 kg/m²,ASA Ⅱ或Ⅲ级。术中连续监测左侧肾脏rSO₂。设定麻醉诱导后肾脏rSO₂为基础值,当术中肾脏rSO₂绝对值≤50%或低于基础值的75%时,定义为肾脏rSO₂异常下降。记录术前及术后24 h尿素氮（BUN）、血清肌酐（SCr）,术后肾功能异常定义为术后24 h血浆SCr＞130 μmol/L或BUN＞7.5 mmol/L。根据术后是否出现肾功能异常将患者分为两组：肾功能正常组和肾功能异常组。采用列联系数分析术中肾脏rSO₂异常下降与术后肾功能异常的相关性。
结果 有40例（34.5%）患者术中出现肾脏rSO₂异常下降,有45例（38.8%）患者术后出现肾功能异常。二元Logistic回归分析显示男性是术后肾功能异常的危险因素（OR=5.490,95%CI 1.526～19.754,P=0.009）。食管癌根治术中肾脏rSO₂的异常下降与术后肾脏功能异常呈正相关（rs=0.587,P=0.009)。
结论 食管癌根治术中肾脏rSO₂异常下降与术后肾功能异常呈正相关。     

心肺转流期间老年患者局部脑氧饱和度与术后认知功能障碍的相关性

目的 探究老年患者心肺转流（CPB）期间局部脑氧饱和度（rSO₂）与术后认知功能障碍（POCD）的相关性。
方法 选择择期行CPB下心脏手术的老年患者84例,男46例,女38例,年龄≥65岁,BMI 18～29 kg/m²,ASA Ⅱ—Ⅳ级。术中应用近红外光谱技术,持续监测rSO₂。采用神经心理学测试方法评估患者术前1 d和术后第7天的认知功能,采用Z值计分法判定POCD。根据术后第7天是否发生POCD将患者分为两组：非POCD组和POCD组。CPB前期包括入室吸氧前至主动脉插管（期间包括麻醉后、手术开始、劈胸骨、悬吊心包）,CPB中期包括CPB开始至CPB结束（期间包括CPB低温恒温期及搭桥或换瓣）,CPB后期包括主动脉拔管和术毕。记录CPB前期、中期、后期rSO2平均值（rSO_2mean）,术中rSO₂最低值（rSO_2min）。采用Logistic回归和拟合曲线分析患者术中rSO₂与POCD的相关性。
结果 有36例（42.9%）患者发生POCD。多因素Logistic回归分析显示,CPB前期rSO_2mean（OR=1.12,95%CI 1.02～1.24,P=0.02）、CPB中期rSO_2mean（OR=1.55,95%CI 1.24～1.95,P<0.05）、CPB后期rSO_2mean（OR=1.32,95%CI 1.15～1.60,P<0.05）和rSO_2min（OR=1.33,95%CI 1.16～1.52,P<0.05）是发生POCD的独立危险因素。拟合曲线显示,CPB中期rSO_2mean（r=-0.60）和rSO_2min（r=-0.57）均与POCD呈线性负相关(P<0.05)。
结论 术中rSO₂降低与患者CPB术后发生POCD具有相关性。术中rSO₂降低可能是POCD的独立危险因素。     

喷射通气频率对硬质支气管镜检查患者通气效果的影响

目的 通过电阻抗断层扫描（EIT）观察喷射式呼吸机在不同喷射通气（JV）频率下对硬质支气管镜检查患者通气效果的影响。
方法 选择择期行硬质支气管镜检查患者90例,男42例,女48例,年龄18～60岁,BMI 18.5～27.9 kg/m²,ASA Ⅰ或Ⅱ级。采用随机数字表法将患者分为三组：低频通气组（J20组）采用20次/分的频率进行喷射通气;常频通气组（J60组）采用60次/分的频率进行喷射通气;高频通气组（J150组）采用150次/分的频率进行喷射通气,每组30例。记录麻醉诱导后通气5 min（T₁）、手术开始5 min（T₂）、手术结束（T₃）时喷射通气下的吸气峰压（PIP）、平均吸气压力（MIP）、氧合指数（PaO₂/FiO₂）、PaCO₂。并通过EIT记录T₁—T₃时肺不同区域（ROI₁、ROI₂、ROI₃、ROI₄）的通气占比及阻抗值（IR）。
结果 与J20组比较,J60组和J150组PIP、MIP、PaO₂/FiO₂明显降低,PaCO₂明显升高（P＜0.05）,在ROI₁、ROI₂、ROI₃、ROI₄区域通气占比均明显降低（P＜0.05）,IR明显降低（P＜0.05）。与J60组比较,J150组PIP、MIP、PaO₂/FiO₂明显降低,PaCO₂明显升高（P＜0.05）,在ROI₁、ROI₂、ROI₃、ROI₄区域通气占比均明显降低（P＜0.05）,IR明显降低（P＜0.05）。T₁—T₃时三组肺ROI₁、ROI₂、ROI₃、ROI₄区域通气占比变化差异无统计学意义。
结论 硬质支气管镜检查的患者在不同喷射通气频率下肺内气体分布改变明显,150次/分的高频喷射通气可在满足氧合的前提下明显改善肺内气体分布。     

双气道喉管用于中心气道狭窄气管支架置入术的效果

目的 评价双气道喉管用于中心气道狭窄气管支架置入术的效果。
方法 选择择期行中心气道狭窄气管支架置入术患者42例,男28例,女14例,年龄18~64岁,ASA Ⅱ或Ⅲ级。采用随机数字表法分为两组：双气道喉管组（D组）和普通喉罩组（C组）,每组21例。麻醉诱导后,D组、C组分别置入双气道喉管和普通喉罩,行机械通气。记录麻醉诱导前（T1）、置入喉管/喉罩开始通气时（T2）、手术开始（T3）、支架置入时（T4）及术毕停止麻醉药后5 min（T5）的MAP、HR和SpO₂。分别于支架置入前和置入后抽取动脉血样行血气分析,记录pH值、PaO₂和PaCO₂。记录手术时间和支架置入调整例数。记录气管黏膜损伤、术后声嘶和术后咽痛的发生情况。
结果 T1—T5时两组MAP、HR和SpO₂差异无统计学意义。与C组比较,D组支架置入后pH值、PaO₂明显升高,PaCO₂明显降低,手术时间明显缩短,支架置入调整例数明显减少,气管黏膜损伤、术后声嘶和术后咽痛发生率明显降低（P<0.05）。
结论 双气道喉管用于中心气道狭窄气管支架置入术,可有效减少并发症的发生。     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.     

The analgesic effect of racemic ketamine in patients with chronic ischemic pain due to lower extremity arteriosclerosis obliterans

Background : Ketamine in sub-dissociative doses has been shown to have analgesic and phantom-Limb pain, where conventional treatment has often failed. Chronic ischemic pain due to lower extremity arteriosclerosis obliterans often responds poorly to analgesics, and the pain-generating mechanisms are not well understood.
Methods : Eight patients with rest pain in the lower extremity due to arteriosclerosis obliterans were given sub-dissociative doses of 0.15, 0.30, or 0.45 mg/kg racemic ketamine and morphine 10 mg as a 5-min infusion on four separate days in a cross-over, double-blind, randomised protocol. Plasma levels of (S)- and (R)-ketamine and their nor-metabolites were analysed with an enantioselective high-performance liquid chromatography (HPLC) method. Pain levels were evaluated with a visual analogue scale (VAS).
Results : Individual pain levels were highly variable during and after all the infusions but the pooled pain levels showed a dose-dependent analgesic effect of ketamine with a transient but complete pain relief in all patients at the highest dose (0.45 mg/ kg). Side-effects, mainly disturbed cognition and perception, were pronounced and dose-dependent. Morphine 10 mg had an analgesic peak at 20 min and 5/8 patients had complete pain relief. The remaining 3 patients also had high baseline pain scores, indicating a higher analgesic potency for the 0.30 and 0.45 mg/ kg ketamine doses than for morphine 10 mg.
Conclusion : We have demonstrated a potent dose-dependent analgesic effect of racemic ketamine in clinical ischemic pain. Due to a narrow therapeutic window, this analgesic effect is probably best utilised in combination with other analgesics.     

Intravenous endotoxin does not increase tissue extravasation of albumin in rats

Background : It is unclear whether activation of the inducible nitric oxide synthase (iNOS) increases or decreases the extravasation of plasma.
Methods : Chloralose anaesthetised male Wistar rats received E. coli lipopolysacharide (LPS), 3 mg kg^-1 i.v., or the corresponding volume of saline, 3 or 5 h before the end of the experiment. Mean arterial pressure (MAP) and heart rate (HR) were recorded. Tissue clearance of radio-labelled albumin, during the last 2 h of each experiment, was determined by a double-isotope method. In separate animals, the serum concentration of nitrite and nitrate was determined, 5 h after LPS or the solvent.
Main Results : LPS initially decreased MAP and lastingly increased HR. In the 3-h LPS animals (n=8), tissue plasma clearance was lower in the heart and calf muscle and increased only in diaphragm, compared to corresponding control animals (n=8). In the 5-h LPS rats, clearance was lowered (n=8) in the entire gastrointestinal tract and in testes, compared to controls (n=8). The serum nitrite/nitrate concentration was higher in animals given LPS (n=6) than in controls (n=6).
Conclusion : After LPS, tissue clearance of albumin was not increased in any major tissue, in spite of increased serum levels of NO end products. Apparently, after activation of iNOS, the augmented release of NO is not necessarily associated with increased albumin extravasation.     

Adrenaline markedly improves thoracic epidural analgesia produced by a low-dose infusion of bupivacaine, fentanyl and adrenaline after major surgery: A randomised, double-blind, cross-over study with and without adrenaline

Background: Basic pharmacological research indicates that there are synergistic antinociceptive effects at the spinal cord level between adrenaline, fentanyl and bupivacaine. Our clinical experience with such a mixture in a thoracic epidural infusion after major surgery confirms this. The objectives of the present study were to evaluate the effects on postoperative pain intensity, pain relief and side effects when removing adrenaline from this triple epidural mixture. Methods: A prospective, randomised, double-blind, cross-over study was carried out in 24 patients after major thoracic or abdominal surgery. Patients with only mild pain when coughing during a titrated thoracic epidural infusion of about 10 ml · h^?1 of bupivacaine 1 mg · ml^?1, fentanyl 2 μg · ml^?1, and adrenaline 2 μg · ml^?1 were included. On the 1^st and 2^nd postoperative days each patient was given a double-blind epidural infusion, at the same rate, with or without adrenaline. The effect was observed for 4 h or until pain when coughing became unacceptable in spite of a rescue analgesic procedure. Rescue analgesia consisted of up to two epidural bolus injections per hour and i.v. morphine if necessary. All patients received rectal paracetamol 1 g, every 8 h. Fentanyl serum concentrations were measured with a radioimmunoassay technique at the start and end of each study period. Main outcome measures were extent of sensory blockade and pain intensity at rest and when coughing, evaluated by a visual analogue scale, a verbal categorical rating scale, the Prince Henry Hospital pain score, and an overall quality of pain relief score. Results: The number of hypaesthetic dermatomal segments decreased (P <0.001) and pain intensity at rest and when coughing increased (P <0.001) when adrenaline was omitted from the triple epidural mixture. This change started within the first hour after removing adrenaline. After 3 h pain intensity when coughing had increased to unacceptable levels in spite of rescue analgesia (epidural bolus injections and i.v. morphine). Within 15–20 min after restarting the triple epidural mixture with adrenaline, pain intensity was again reduced to mild pain when coughing. Serum concentration of fentanyl doubled from 0.22 to 0.45 ng · ml^?1 (P <0.01), and there was more sedation during the period without adrenaline. Conclusions: Adrenaline increases sensory block and improves the pain-relieving effect of a mixture of bupivacaine and fentanyl infused epidurally at a thoracic level after major thoracic or abdominal surgery. Serum fentanyl concentrations doubled and sedation increased when adrenaline was removed from the epidural infusion, indicating more rapid vascular absorption and systemic effects of fentanyl.     

Utilisation des médicaments prokinétiques en réanimation : indications et limites ?

Enteral feeding is often limited by gastric and intestinal motility disturbances in critically ill patients, particularly in patients with shock. So, promotility agents are frequently used to improve tolerance to enteral nutrition. This review summaries the pathophysiology, presents the available pharmacological strategies, the clinical data, the counter-indications and the principal limits. The clinical data are poor. No study demonstrates a positive effect on clinical outcomes. Metoclopramide and erythromycin seems to be the more effective. Considering the risk of antibiotic resistance, the first line use of erythromycin should be avoided in favor of metoclopramide.     

Anesthésie générale chez l’enfant : quid des pratiques en 2010 ?

Introduction

The practice of pediatric anesthesia requires a regular update of scientific knowledge and technical skills. To provide the most adequate Continuing Medical Education programs, it is necessary to assess the practices of pediatric anesthesiologists. Thus, the objective of this survey was to draw a picture of the current clinical practices of general anesthesia in children, in France.

Material and methods

One thousand one hundred and fifty questionnaires were given to anesthesiologists involved in pediatric cases. These questionnaires collected information on various aspects of clinical practice relative to induction, maintenance, recovery from general anaesthesia and also classical debated points such as children with Upper Respiratory Infection (URI), emergence agitation, epileptoid signs or anaesthetic management of adenoidectomy. Differences in practices between CHG (general hospital), CHU (teaching hospital), LIBERAL (private) and PSPH (semi-private) hospitals were investigated.

Results

There were 1025 questionnaires completed. Fifty-five percent of responders worked in public hospitals (CHG and CHU); 77% had a practice that was 25% or less of pediatric cases. In children from 3 to 10 years: 72% of respondents used always premedication and two thirds performed inhalation induction in more than 50% of cases. For induction, 53% used sevoflurane (SEVO) at 7 or 8%. Respondents from LIBERAL used higher SEVO concentrations. Tracheal intubation was performed with SEVO alone (37%), SEVO and propofol (55%) and SEVO with myorelaxant (8%), 93% of respondents used a bolus of opioid. For maintenance, the majority of respondents used SEVO associated with sufentanil; desflurane and remifentanil were more frequently used in CHU. Two thirds of respondents used N₂O. Depth of anesthesia was commonly assessed by hemodynamic changes (52%), end tidal concentration of halogenated (38%) or automated devices based on EEG (7%). In children with URI, 98% of respondents used SEVO for anesthesia. To control the airway 42% used a tracheal tube, 30% a laryngeal mask and 20% a facial mask. Emergence agitation was an important concern for two thirds of respondents, while epileptoid signs were considered as important by only 20%. Eighty-nine percent of respondents practiced anesthesia for adenoidectomy. Anesthesia was induced by inhalation of SEVO 7–8% (41%), 6% (39%) or 4% (12%), 66% put an intravenous line (less frequently in LIBERAL). 67% of the responders managed adenoidectomy without any device to control the airway (more frequently in LIBERAL), 32% administrated a bolus of opioid (less frequently in LIBERAL).

Discussion

This survey demonstrated that the practices regarding general anesthesia in children are relatively homogenous. Most of the differences appeared between LIBERAL and the others structures; the anaesthetic management for adenoidectomy illustrates these findings.     

Intérêt d’une rééducation précoce pour les patients neurologiques

Rehabilitation improves the functional prognosis of patients after a neurologic lesion, and tendency is to begin rehabilitation as soon as possible. This review focuses on the interest and the feasibility of very early rehabilitation, initiated from critical care units. It is necessary to precisely assess patients’ impairments and disabilities in order to define rehabilitation objectives. Valid and simple tools must support this evaluation. Rehabilitation will be directed to preventing decubitus complications and active rehabilitation. The sooner rehabilitation is started; the better functional prognosis seems to be.     

Risiko Schlaganfall — Öffentlichkeitsarbeit und Aufklärung dringend erforderlich

Zusammenfassung Das wesentliche — und zugleich noch wenig ausgeschöpfte — Potenzial der Schlaganfallmedizin liegt in der langfristigen Prophylaxe. Durch Beeinflussung von Lifestylefaktoren wie Ernährungsgewohnheiten, Zigarettenkonsum und körperlichem Training durch entsprechende Aufklärung ließe sich ein erheblicher Teil an zerebralen Ereignissen vermeiden. Ein weiterer in Deutschland noch zu wenig beachteter Faktor ist die konsequente Blutdruckeinstellung. Breitgestreute Aufklärung könnte außerdem potenziellen Patienten helfen, bereits auftretende Warnsymptome wie die transiente ischämische Attacke richtig einzuschätzen, um eine rechtzeitige Behandlung zu ermöglichen.