骨组织工程快速成型支架改性的相关研究

目的探讨胶原杂化及磷灰石表面沉积改性后的聚乳酸一羟基乙酸共聚物／β-磷酸三钙（PLGA／β—TCP）作为快速成型支架应用于骨组织工程的可行性。方法使用骨髓基质干细胞对胶原杂化及磷灰石表面沉积改性后的PLGA／β-TCP的生物相容性进行评估，通过扫描电镜观察改性后材料的表面特性及细胞与材料复合的形态学特征；细胞与材料复合后的繁殖与分化能力分别使用细胞计数及碱性磷酸酶定量方法进行评估。结果通过对亲水性、细胞增殖能力及碱性磷酸酶测定证实改性后的PLGA／β-TCP快速成型支架较单纯材料其亲水性及生物相容性有明显提高（P〈0．05）。结论胶原杂化及磷灰石表面沉积改性后的PLGA／β—TCP快速成型支架可作为三维支架应用于骨组织工程。     

新型聚乳酸-羟基乙酸(PLGA)支架的细胞相容性研究

目的研究骨髓基质干细胞(BMSCs)与该聚乳酸-羟基乙酸(PLGA)类支架的细胞相容性及体外粘附情况,为制备负载多种细胞因子的PLGA类支架提供研究基础。方法抽取新西兰兔骨髓,用全骨髓培养法获取单核细胞,经条件培养液体外诱导、扩增。设立空白BMSCs组和具有良好细胞相容性的β-磷酸三钙(β-TCP)为对照组。BMSCs以1×106/mL浓度接种于PLGA和β-TCP上,通过倒置相差显微镜、扫描电镜观察细胞生长及细胞与材料的附着情况。以MTT实验、流式细胞仪等手段检测各组细胞增殖和细胞周期变化情况。结果BMSCs可较好粘附于PLGA支架上,且该PLGA类支架对细胞增殖、生长周期无明显影响。结论该PLGA类支架的细胞相容性较好,并可进一步作为多种细胞因子载体构建缓释型支架,从而用于骨组织工程。     

基于增材制造和凝胶注模成型技术的多孔生物陶瓷支架制备与表征

目的探讨基于增材制造和凝胶注模成型技术的多孔β-磷酸三钙（TCP）生物陶瓷支架的制备方法及其表征。方法利用计算机辅助设计（CAD）软件设计支架内部孔隙结构,通过光固化快速成型技术制造相应的树脂模具,在模具中填充生物材料,待其固化后通过热分解去除树脂模具,然后对所形成的多孔β-TCP支架的微观孔隙结构特征、力学性能以及体外细胞相容性进行检测。结果多孔β-TCP支架孔隙结构与设计结构一致,孔隙率为45.1%±1.2%,孔的尺寸为300～500μm;力学性能测试表明,支架的平均抗压强度为5.3±0.8 MPa;成骨细胞能够在支架上黏附生长,支架具有良好的生物相容性。结论基于增材制造技术和凝胶注模成型工艺的多孔生物陶瓷支架制备方法,可实现支架复杂外形与内部微结构的精确控制和一体化制造。     

唑来膦酸、聚乳酸-羟基乙酸聚合物、β-磷酸三钙复合支架修复去势大鼠股骨干骺端骨缺损的实验研究

目的唑来膦酸、聚乳酸-羟基乙酸聚合物、β-磷酸三钙(ZA、PLGA、β-TCP)复合支架对去势大鼠股骨干骺端骨缺损的修复作用。方法雌性SD大鼠经过双侧去卵巢手术后饲养3个月建立骨质疏松模型,随后在大鼠双侧股骨干骺端建立直径为3 mm圆形骨缺损,上述大鼠随机分为4组;分别置入ZA、PLGA支架,β-TCP支架和ZA、PLGA、β-TCP复合支架,不置入支架材料的为对照组。术后12周取材,通过Micro-CT扫描重建和病理组织学评价三组支架材料的成骨作用。结果术后观察发现空白对照组骨缺损未修复,骨缺损断端硬化,而其他3组骨缺损均有不同程度修复。植入骨质疏松大鼠体内12周后,三组材料随着材料的降解均有新生骨长入,且三组新骨生成率均显著优于对照组(P0.05),缺损区域都有较高BV/TV、Tb.Th、Tb.N、Conn.D、骨矿化沉积率(MAR)和较低的Tb.Sp,其中以ZA、PLGA、β-TCP组最高。Micro-CT和病理组织学结果提示ZA、PLGA、β-TCP组骨修复效果较ZA、PLGA与β-TCP组更好。结论 ZA、PLGA、β-TCP复合支架具有明显促进去势大鼠股骨干骺端骨缺损修复的作用。     

载利福喷丁/聚乳酸-聚乙醇酸共聚物微球制备及体外释放

目的：制备可用于持续抑制脊柱结核术后病灶残留结核分枝杆菌的载利福喷丁／聚乳酸-聚乙醇酸共聚物[ Poly（ lactic-co-glycolic acid）, PLGA]微球,并研究其体外释放性能。方法通过乳化-溶剂挥发法制备载利福喷丁／PLGA微球,光学显微镜和扫描电镜观察微球形貌,激光粒度分布仪测定微球粒径及分布,紫外分光光度计测定微球载药量及包封率。检测利福喷丁抗结核分枝杆菌的最低抑菌浓度,并以pH＝7．4的PBS缓冲溶液为释放介质,紫外分光光度计检测载药微球体外释放特性。结果载利福喷丁／PLGA微球成球形状良好,表面光滑,分散性好,粒径分布均匀,平均粒径为25．49μm。载药量及包封率分别为21．37％±0．16％和74．79％±2．71％。体外释放实验显示在突释期内,利福喷丁释放量占载药微球中药物含量的37．08％±1．68％;在缓释期内载药微球释药速度减慢,第5周释放量仍超过利福喷丁抗结核分枝杆菌的最低抑菌浓度,35 d后体外累积释放量为80．67％±0．97％,仍高于利福喷丁抗结核分枝杆菌的最低抑菌浓度2μg／mL。结论 PLGA是一种理想的控缓释材料,所制备的载利福喷丁／PLGA微球具有良好的控释效果,是一种有效的抗结核缓释剂型。     

高孔隙连通性β-磷酸三钙细胞支架的制备

目的 改进多孔β-TCP支架的制备方法,提高支架的孔隙连通性、孔隙结构的均匀性以及支架的抗压特性.方法 利用两阶段中和反应工艺,制备β-TCP粉末原料;将粘结剂均匀涂布在致孔剂表面后与β-TCP粉末混合,添加高温液相传质介质,再次混合形成致孔剂与β-TCP粉末的均匀混合体,加压成型、煅烧制备三维多孔细胞支架;X-衍射检测原料和支架的成分,扫描电镜观察支架的孔隙结构,力学实验仪测定支架的抗压性能.结果 原料和支架化学成分均为β-TCP;支架的孔隙呈球形、分布均匀、孔隙间几乎完全连通,大孔平均孔径781.38±70.47(n=12)μm,连通孔径297.88±66.86(n=13)μm;孔隙率、吸水率和抗压强度分别为52.27±0.11(n=6)Vol%、31.82±0.13(n=6)Wt%和11.40±0.07(n=6)MPa.结论 两阶段中和反应工艺能够制备出纯的β-TCP粉末,改进的支架制备技术,可以制备出孔隙率高、强度大、孔隙大小可控、孔隙分布均匀、孔隙间几乎完全连通的β-TCP支架,具备了组织工程要求的结构特征.     

多孔钙磷陶瓷表面浸涂制备明胶/HA复合涂层

目的采用有机泡沫浸渍法制备β-磷酸三钙（β-TCP）多孔生物陶瓷，以明胶／羟基磷灰石（Hydroxyapatite，HA）复合浆料对其进行表面浸涂处理。本研究旨在保证高孔隙率的前提下提高多孔支架的综合性能。方法利用X-射线衍射仪对β-TCP多孔生物陶瓷进行相组成分析，并研究多孔支架涂覆前后的孔隙率和孔隙特征的变化以及不同明胶／HA比例对支架性能的影响。结果β-TCP多孔生物陶瓷烧结后的主要成分为（Ca，Mg），（PO4）2和β-CaEP2O7。涂覆前后多孔支架的孔隙率并没有发生明显改变，但涂覆处理后表面粗糙度明显增大，涂层与支架具有良好的结合界面，涂层中有大量的微孔存在。结论涂覆处理在β-TCP多孔生物陶瓷支架孔隙率基本不变的情况下，成功地在其表面制备出明胶／HA复合涂层，随之形成的粗糙表面形貌，将有利于细胞的早期粘附。     

明胶-硫酸软骨素-透明质酸钠作为组织工程软骨支架的实验研究

目的探索明胶-硫酸软骨素-透明质酸钠多孔支架的制备方法和其作为组织工程软骨支架的可行性。方法光镜和扫描电镜观察-20℃、-80℃及液氮条件下冷冻抽真空干燥制备的明胶-硫酸软骨素-透明质酸钠支架的孔径、孔隙率、交通孔和密度;测定不同条件制备的支架材料与正常软骨的压缩载荷-形变曲线;分离、扩增兔骨髓基质干细胞(mesenchymalstemcells,MSCs),接种于不同条件制备的支架材料上培养,MTT检测MSCs在支架上的黏附率及多孔支架对细胞增殖功能的影响。结果在-20℃、-80℃及液氮条件下制备的支架材料具有疏松多孔结构,孔径依次为300±45μm、230±30μm和45±10μm,孔隙率为81%、79%和56%,密度为9.41±0.25μg/mm3、11.50±0.36μg/mm3和29.50±0.61μg/mm3;-80℃和液氮条件下制备的支架材料,力学强度接近于正常软骨;MTT测得细胞在-20℃、-80℃及液氮条件下制备的支架材料,黏附率分别为85.0%、87.5%和56.3%;可轻度促进MSCs增殖。结论-80℃条件下抽真空干燥制备的明胶-硫酸软骨素-透明质酸钠多孔支架,具有良好的孔径、孔隙率和抗压缩载荷能力,与MSCs具有较好的相容性,是软骨组织工程中的一种新型仿生支架材料。     

不同比例三联抗结核药物复合缓释材料的释药性能观察

目的 :观察不同比例三联抗结核药物复合缓释材料在模拟体液中的药物释药性能。方法 :以聚乳酸-羟基乙酸(PLGA)作为载体,采用双乳、喷涂、冷冻干燥溶剂挥发法制备不同比例抗结核药物的复合缓释材料:A组,异烟肼(INH,H)∶利福平(RFP,R)∶吡嗪酰胺(PZA,Z)=15∶15∶30;B组,H∶R∶Z=20∶30∶50;C组,H∶R∶Z=30∶30∶120;D组,H∶R∶Z=80∶120∶250。药物总质量与PLGA之比为1∶5。扫描电子显微镜(SEM)观察HRZ/PLGA复合缓释材料的表面形态,高效液相色谱法(HPLC)检测其在模拟体液中H、R、Z三种药物的释放浓度,计算药物累计释放量及释放率,分析其体外缓释性能。结果:A组和B组缓释材料表面分散均匀,空隙规则、分布均匀,直径分别为23.07±0.38μm和25.67±1.26μm;C组和D组缓释材料分散欠均匀,空隙不规则、分布欠均匀,直径分别为31.25±1.98μm和45.67±3.26μm。A组H、R、Z分别于42d、56d、42d的累计缓释度超过50%,于70d时的阶段释药量分别为157.43±057μg、129.29±0.14μg、196.43±0.28μg,浓度分别为28.486μg/ml、23.525μg/ml、39.265μg/ml。B组H、R、Z分别于35d、42d、35d的累计缓释度超过50%,于70d时阶段释药量分别为9.89±0.96μg、21.71±0.42μg、51.12±0.87μg,浓度分别为1.789μg/ml、1.618μg/ml、10.242μg/ml。C组H、R、Z分别于21d、35d、42d的累计缓释度均超过50%,于70d时阶段释药量分别为1.76±0.49μg、8.43±0.31μg、81.14±0.58μg,浓度分别为0.352μg/ml、1.618μg/ml、10.242μg/ml。D组H、R、Z分别于28d、42d、35d的累计缓释度均超过50%,于70d时阶段释药量分别为1.71±0.21μg、14.01±0.42μg、65.57±0.26μg,浓度分别为0.312μg/ml、2.128μg/ml、13.516μg/ml。70d时A组三种药物浓度均大于各自的10倍最低抑菌浓度(MIC),且A组分散均匀,空隙规则、分布均匀,直径约为23.07±0.38μm,三种药物在不同的时间段释放行为不相同,前14d药物缓释规律按Higuchi方程拟合最好,即前14d三种药物按照扩散的形式进行缓释,14d后三种药物按照零级动力学缓释曲线释放,即等量缓释。其余3组均有药物未达到10倍MIC。结论:复合HRZ/PLGA缓释材料具有优良的载药及药物缓释效果,是一种理想的复合药物缓释系统,其中H∶R∶Z=15∶15∶30的HRZ/PLGA缓释材料为较佳配方。     

羟基磷灰石/β－磷酸三钙/甲壳素复合多孔支架材料的制备及生物相容性研究

目的 探讨羟基磷灰石/β-磷酸三钙/甲壳素(HAP/β-TCP/CS)多孔支架的制备及其与人体骨髓间质干细胞(MSCs)的生物相容性.方法 以羟基磷灰石粉体为基体,采用有机泡沫浸渍-发泡复合成型工艺制备出羟基磷灰石/β-磷酸三钙多孔支架,再将该多孔支架与甲壳素复合得到有机-无机复合支架,然后通过体外培养实验评价该复合支架的干细胞相容性.结果 复合甲壳素可以显著提高HAP/β-TCP支架的抗压强度,并且该支架具有三维连通网状结构,细胞在支架上粘附,生长良好.结论 该复合多孔支架具有良好的干细胞亲和性和生物相容性.     

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.     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.     

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.