不同射血分数患者非体外循环冠状动脉旁路移植术中右心功能变化

目的研究不同射血分数患者非体外循环冠状动脉旁路移植术(OPCABG)术中右心功能变化规律。方法选择50例择期行OPCABG的患者,ASAⅡ或Ⅲ级,其中EF≥50%组30例,EF≤35%组20例,麻醉诱导后放置肺动脉导管,分别记录开心包后(基础值)、前降支(LAD)搭桥、回旋支(LCX)搭桥、后降支(PDA)搭桥及关胸骨后的CVP、平均肺动脉压(MPAP)、肺动脉楔压(PAWP)、心脏指数(CI)、右室射血分数(RVEF)、右室舒张末容积指数(RVEDVI)等。结果与基础值比较,LAD、LCX、PDA搭桥两组CVP、MPAP、PAWP明显升高(P<0.05);LCX、PDA搭桥两组CI、RVEF明显降低(P<0.05);而EF≥50%组RVEDVI明显降低、EF≤35%组RVEDVI明显升高(P<0.05)。与EF≤35%组比较,LCX、PDA搭桥、关胸后EF≥50%组RVEF明显升高(P<0.05);而LCX、PDA搭桥EF≥50%组RVEDVI明显降低(P<0.05)。结论在OPCABG术中行LCX和PDA搭桥期间可见右心功能受限,而不同射血分数患者之间右心功能变化规律有不同。     

非体外循环冠状动脉旁路移植术中血流动力学的变化

目的分析非体外循环冠状动脉旁路移植术(off-pum p coronary artery bypass grafting,OPCAB)中血流动力学的变化特点。方法连续100例冠心病患者接受OPCAB,术中对各病变血管进行旁路移植血管吻合时的血流动力学指标进行监测。全组完成左乳内动脉(L IM A)与左前降支(LAD)吻合97例,大隐静脉或桡动脉与右冠状动脉(RCA)主干、后降支(PDA)、左心室后支(PLB)吻合84例,左回旋支(LCX)吻合50例,钝缘支(OM)吻合27例,对角支(DG)吻合25例。每例患者移植血管支数为3.1±0.7支。结果吻合LAD、DG时除心率(HR)较基础值增快,平均动脉压(M AP)和左心室每搏做功指数(LV SW I)较基础值降低外(P<0.05),其它指标无明显变化。吻合LCX、PDA、PLB和OM时血流动力学指标有明显的变化,HR、中心静脉压(CVP)较基础值明显升高(P<0.05),M AP、心脏指数(C I)、每搏指数(S I)、右心室射血分数(RVEF)、右心室舒张期末容积(RVEDV)、LV SW I、右心室每搏做功指数(RV SW I)较基础值明显降低或减少(P<0.05)。术毕各指标均趋于正常,C I有明显的改善。结论OPCAB中吻合LAD和DG时对血流动力学影响较小,而吻合LCX、PDA、PLB和OM时对血流动力学有明显的影响,术毕各血流动力学指标趋于正常,心脏功能有明显的改善。     

二维斑点追踪技术评价麻醉诱导和正压通气对不同容量状态时双心室功能的影响

目的 基于二维斑点追踪技术评价全麻诱导和正压通气对不同容量状态患者双心室功能的影响。
方法 选择择期全麻胃肠手术患者60例,男38例,女22例,年龄50～70岁,ASA Ⅰ或Ⅱ级。入室监护后行容量负荷试验,20 min内静脉输注生理盐水250 ml。于容量负荷试验前、后分别测量左心室流出道（LVOT）直径（D）和主动脉瓣速度时间积分（VTI）,记录容量负荷试验前、后每搏输出量（SV）,并计算ΔSV。根据ΔSV将患者分为两组：容量反应性阳性组（R组,ΔSV≥15%,n=33）和容量反应性阴性组（N组,ΔSV<15%,n=27）。容量负荷试验结束后10 min麻醉诱导前,行第1次经胸超声心动图检查。随后行全麻诱导,气管插管后行肺保护性通气（V_T 7 ml/kg,PEEP 5 cmH₂O,FiO₂ 60%）,待麻醉诱导后10 min血流动力学平稳,行第2次经胸超声心动图检查。记录诱导前和诱导后心肌功能参数,采用二维斑点追踪技术测量左心室整体纵向应变（左心室GLS）和右心室游离壁纵向应变（右心室FWLS）,计算各指标诱导前后的相对变化值。
结果 与诱导前比较,诱导后两组VTI、左心室GLS、三尖瓣环收缩期位移（TAPSE）、右心室FWLS明显降低（P<0.05）;三尖瓣口血流舒张早期峰值速度与三尖瓣环舒张早期峰值速度比值（右心室E/E′）、右心室心肌做功指数（右心室MPI）明显升高（P<0.05）。诱导前后两组左心室射血分数（LVEF）、二尖瓣口血流舒张早期峰值速度与二尖瓣环舒张早期峰值速度比值（左心室E/E′）差异无统计学意义。与N组比较,R组主动脉瓣速度时间积分变化值（ΔVTI）、左心室整体纵向应变变化值（左心室ΔGLS）、三尖瓣环收缩期位移变化值（ΔTAPSE）、右心室游离壁纵向应变变化值（右心室ΔFWLS）明显降低（P<0.05）;左心室做功指数变化值（左心室ΔMPI）、三尖瓣口血流舒张早期峰值速度与三尖瓣环舒张早期峰值速度比值变化值（右心室ΔE/E′）、右心室心肌做功指数变化值（右心室ΔMPI）明显升高（P<0.05）。两组左心室射血分数变化值（ΔLVEF）、二尖瓣口血流舒张早期峰值速度与二尖瓣环舒张早期峰值速度比值变化值（左心室ΔE/E′）差异无统计学意义。
结论 麻醉诱导和正压通气会诱发全麻患者左心室收缩功能及右心室收缩和舒张功能降低,在低血容量患者中尤为显著。     

右美托咪定对二尖瓣置换术患者左右心室收缩和舒张功能的影响

目的 观察右美托咪定对心肺转流（CPB）下行二尖瓣置换术患者左右心室收缩和舒张功能的影响。方法 择期CPB下行二尖瓣置换术患者32例,男9例,女23例,年龄42～70岁,BMI 18~28 kg/m²,ASA Ⅱ或Ⅲ级。采用随机数字表法分为两组:右美托咪定组（D组）和对照组（C组）。两组术中麻醉维持均采用静脉复合麻醉,D组于切皮后经微量注射泵静脉注射右美托咪定负荷剂量1 μg/kg,10 min内注射完后以0.5 μg·kg^-1·h^-1维持给药至术毕,C组静脉注射等量生理盐水。于麻醉诱导后（T0）、CPB停机后30 min(T1)、60 min(T2)记录HR、MAP、CVP、心脏指数（CI）、左心室射血分数(LVEF)等血流动力学指标,并于同时点记录二尖瓣瓣环等容收缩期峰值速度（Sm1）、射血期峰值速度（Sm2）、二尖瓣舒张早期血流峰值速度与二尖瓣瓣环舒张早期峰值速度的比值（E/Ea-MV）、三尖瓣瓣环等容收缩期峰值速度（St1）、射血期峰值速度（St2）、三尖瓣舒张早期峰值速度与三尖瓣瓣环舒张早期血流峰值速度的比值（E/Ea-TV）。结果 与T0时比较,T1—T2时两组HR明显增快（P<0.05）,MAP明显降低（P<0.05）,CVP、CI明显升高（P<0.05）。T0—T2时两组HR、MAP、CVP、CI、LVEF差异均无统计学意义。T0—T2时两组Sm1、Sm2、E/Ea-MV组内组间差异均无统计学意义。与T0时比较,T1—T2时C组E/Ea-TV明显升高,T2时D组E/Ea-TV明显升高（P<0.05）。T0—T2时两组St1、St2、E/Ea-TV差异无统计学意义。结论 右美托咪定并不能改善左右心室舒张功能受损的程度,亦未增加心肌受损程度。     

不停跳冠状动脉旁路移植术中血流动力学的改变及处理

目的分析不停跳冠状动脉旁路移植（OPCAB）术中血流动力学变化特点,探讨维持血流动力学稳定的管理措施。方法2005年1月至8月连续100例病人接受OPCAB。共完成旁路血管313支,平均（3．1±0．7）支。术中监测每支冠脉远端吻合时的血流动力学指标,分析其变化特点。术中采取了心包悬吊、心脏位置改变、确保吻合口质量及合理应用血管活性药物等一系列管理措施,维持术中血流动力学稳定。结果前降支（LAD）远端吻合时,血流动力学变化较小。重建LAD血供后,平均动脉压（MAP）、左室运动指数（INSWI）、每搏输出指数（SI）、心排指数（CI）等指标升高。侧壁、下壁冠脉回旋支（LCX）、后降支（PDA）、左室后支（PLB）、钝缘支（OM）的远端吻合时,血流动力学波动大,心率（HR）、中心静脉压（CVP）明显升高,MAP、CI、右室舒张末容积（RVEDV）、LVSWI、右室做功指数（RVSWI）有明显下降。术毕CI明显改善。全组无死亡,除1例术中因血流动力学持续不稳定改为体外循环下手术和术后2例发生二次开胸止血外,无其他严重并发症,心绞痛缓解,心功能明显改善,均顺利出院。结论OPCAB术中,LAD远端吻合时血流动力学波动小,重建血供后,心肌收缩功能改善。侧壁、下壁冠脉远端吻合时血流动力学波动大。术中采用心包悬吊、心脏体位改变、保证吻合口质量及血管活性药物的合理应用等一系列措施是确保手术成功的关键。     

经单根冠状动脉与冠状静脉窦同时灌注心肌保护的实验研究

目的探讨经单根冠状动脉和冠状静脉窦（CS）顺行性／逆行性同时心肌灌注（SARC）的效果。方法将离体猪心分别经左前降支（LAD）、左回旋支（LCX）或右冠状动脉（RCA）中的1支和CS行SARC，再依次向动、静脉灌注通路内注入磁共振造影剂[钆喷替酸葡甲胺（Gd-DTPA）]。应用磁共振成像（MRI）检测心肌内造影剂的分布以及对非灌注冠状动脉回流液进行分析，评估心肌灌注效果。结果SARC期间经单根冠状动脉注入Gd-DTPA不但使其支配区域磁共振信号增强，而且其余2根非灌注冠状动脉的支配区域信号也增强（包括右心室游离壁）；而SARC期间经CS注入Gd-DTPA只引起非灌注冠状动脉支配区变亮，灌注冠状动脉的支配区和右心室游离壁的信号强度无改变。SARC期间非灌注冠状动脉收集的回流液速度分别为：LAD 10．5～17．7ml／min，LCX 9．7～15．2ml／min，RCA 4．7～7．8ml／min。结论经单根冠状动脉和CS同时灌注可以提供全面均匀的心肌灌注，足以防止非灌注冠状动脉支配区发生心肌缺血损伤。     

二尖瓣手术同期修复中度及以下三尖瓣关闭不全对三尖瓣及右心功能早中期预后的影响

目的 探讨二尖瓣手术同期修复中度及以下三尖瓣关闭不全对患者三尖瓣及右心功能早中期预后的影响。方法 回顾性分析2011—2014年于阜外医院因二尖瓣疾病需要接受心脏外科手术合并中度及以下三尖瓣反流461例患者的临床资料，其中男309例、女152例，中位年龄53.00(44.00,60.00)岁。根据是否同期行三尖瓣手术修复（包括DeVega术和Kay’s术的缝线成形和成形环植入）分为单独二尖瓣手术组（nTAP组，289例）和同期三尖瓣手术组（TAP组，172例），记录两组患者手术前后左心室舒张末期内径、室间隔厚度、左心室后壁厚度、右心室内径的变化。同时对43例三尖瓣环直径<40 mm的TAP组患者术前、术后右心室内径变化进行亚组分析，探讨三尖瓣手术对改善患者右心功能的影响。结果 中位随访时间为3.00(0.10～9.30)年。围术期无患者死亡。术后3个月，TAP组患者右心室前后径较nTAP组显著改善[右心室前后径变化分别为–1.00（–3.00,1.00）mm vs. 0.00（–0.20,2.00）mm,P=0.048]。术后3年，TAP组右心室前后径的改善仍然较nTAP组患者显...     

尼卡地平联合艾司洛尔对冠状动脉搭桥期间全身和组织氧合的影响

目的探讨尼卡地平联合艾司洛尔(N E)是否对非心肺转流(CPB)冠状动脉搭桥术(OPCAB)期间全身和组织氧合具有保护作用。方法选择20例行OPCAB病人,随机分为尼卡地平联合艾司洛尔组(N E组)和硝酸甘油联合艾司洛尔组(X E组),每组10例。麻醉诱导后,输注N E或X E混合液维持MAP 70~80 mmHg。于麻醉诱导后(T1)、搭桥前(T2)、前降支(LAD)搭桥(T3)、后降支(PDA)搭桥(T4)、回旋支(LCX)搭桥(T5)、搭桥结束(T6)和术毕(T7)测定血液动力学、动脉血乳酸(Lac)含量和胃粘膜二氧化碳压力(PgCO2)等参数,计算氧供(DO2)、氧耗(VO2)和胃粘膜pH(pHi)。结果OPCAB期间,N E组病人的心指数(CI)明显高于(P<0.05)或等于基线水平;而X E组病人则轻度下降。N E组病人在T4、T5,X E组病人从T3至T6的心脏每搏量指数(SVI)均明显下降(P<0.05);N E组病人的周围血管阻力指数(SVR1)明显下降,且明显低于X E组病人(P<0.05);两组病人的HR术中均明显增加(P<0.05)。输注N E混合液后DO2均高于或等于基线水平(P<0.05),血Lac含量处于正常范围;X E组病人的DO2搭桥期间均下降,特别是LCX搭桥时(P<0.05),而且血Lac含量显著升高并超出正常范围(P<0.05)。N E组病人OPCAB期间的pHi均高于7.35,而X E组病人从T4至T7则低于7.35。结论尼卡地平联合艾司洛尔配方对OPCAB期间全身和组织氧合具有保护作用。     

冠心病合并完全性左束支传导阻滞冠状动脉旁路移植术后完全恢复1例

病人 男,60岁.间断性胸闷4个月,加重1周,高血压史20年,糖尿病史8年,高血脂史8年.心脏彩色超声心动图检查示射血分数(EF)0.26,短轴缩短率(FS)0.13,左心室舒张末内径63.2 mm,收缩末内径55.3 mm,室间隔厚16.9 mm;左心增大,左心室肥厚,左心室节段性室壁运动减低并消失,主动脉瓣轻度关闭不全,二尖瓣、三尖瓣轻度关闭不全,中度肺动脉高压,左心室收缩功能明显减低.冠状动脉造影检查见冠状动脉3支狭窄,前降支(LAD) 70%～80%、回旋支(LCX)95%,均为近、中段狭窄,远端血管光滑;右冠状动脉(RCA)全程不规则狭窄.在术前28 d中共行11次心电图检查均为完全性左束支传导阻滞(CLBBB).     

慢性肾脏疾病患者左室结构及功能改变的超声评价

目的：应用超声心动图评价慢性肾脏疾病（CKD）患者左室结构及功能改变,探讨不同程度CKD患者左室改变情况。方法：对CKD非透析患者39例（CKD2～3期组19例,CKD4～5期组20例）及对照组40例进行常规肾脏扫查及超声心动图检查,通过二维超声观察CKD患者肾脏形态结构、实质回声、皮髓质分界、血流信号改变;通过超声心动图获得左室结构参数：左房内径（LAD）、左室舒张末期内径（I。VID）,左室质量指数（LV—MI）、左室相对室壁厚度（RWT）;左室功能参数：左室射血分数（EF）、二尖瓣口舒张早期血流速度E峰、晚期A峰、E／A、舒张早期二尖瓣环运动速度Em,E／Era。结果：①CKD2～3期组19例患者中6例患者肾脏声像图有明显改变,CKD4～5期组中18例患者肾脏声像图有显著改变;②与正常组比较,cKD2～3期组LVM、RWT、LAD均显著增高,CKD4～5期组LVID、LVMI、E、A、E／Em增高,DTE、E／A、Em减低,与CKD2～3期组比较,CKD4～5期组LVM、RWT、LAD、LVID、LVMI、E、A、EjEm显著增加,DTE显著减低,E／A、Em无明显差异;③CKD2～3期组中有5例左室重构（26．3％）,CKD4～5期组患者中有17例左室壁重构（85％）。结论：早中期CKD患者其肾脏结构二维超声改变不明显,而超声心动图能早期检测到CKD患者左室构型及左室舒张功的改变,为临床上该病治疗及心血管并发症的预防提供有价值的参考信息。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.