腹腔镜术中体位对呼吸循环功能的影响

目的观察腹腔镜手术期间体位对患者呼吸循环功能的影响。方法A组,女性腹腔镜胆囊切除术患者30例,术中取反向特伦伯格卧位;B组,女性卵巢囊肿切除术患者30例,术中取特伦伯格卧位,监测气腹前(T0)、气腹后体位改变前(T1)、体位改变后15 min(T2)、30 min(T3)、术毕气管导管拨出后10 min(T4)时的MAP、HR、SpO2、肺胸顺应性(Comp)、气道阻力(Raw)、气道峰压(Ppeak)、PETCO2。结果T1、T2、T3时与T0时比较两组HR、MAP、Ppeak、Raw、PETCO2明显升高,Comp降低(P<0.05);T2时点后A组Raw、Ppeak、PETCO2明显低于B组,Comp高于B组(P<0.05),T4时B组患者HR、MAP明显高于A组。结论气腹与体位均使患者循环动力学发生改变,通气功能下降,其中以特伦伯格卧位下降更为明显。     

盐酸戊乙奎醚对妇科腹腔镜手术患者术中肺通气功能的影响

目的 研究术前应用盐酸戊乙奎醚是否可以改善妇科腹腔镜患者术中肺通气功能,并观察其对循环指标的影响.方法 选择择期腹腔镜下子宫切除或子宫肌瘤剔除术患者42例,采用信封法随机分为2组(每组21例),试验组(P组)在气管插管后10 min缓慢静注盐酸戊乙奎醚20 μg/kg,对照组(N组)静注生理盐水.记录给药前(T0)、气腹后5(T1)、30(T2)、60(T3)、90 min(T4)时患者心率(HR)、收缩压(SBP)、舒张压(DBP)、血氧饱和度(SpO2),呼气末二氧化碳分压(PETCO2)、肺顺应性(Compl)、气道阻力(Raw)、气道峰压(Ppeak)、平台压(Pplat)与术中尿量、手术时间、输血输液量. 结果 给药前(T0)两组患者肺功能各项指标差异无统计学意义(P＞0.05);气腹后两组患者与T0时比较Ppeak、Pplat、Raw升高而Compl下降,T1、T2、T3、T4时P组患者Raw分别为(14.8±1.4)、(14.6±1.6)、(14.6±1.3)、(14.4±1.2) cm H2O·L-1·s-1(1 cm H2O=0.098 kPa),而N组分别为(16.2±1.6)、(16.1±1.8)、(16.1±1.9)、(16.1±1.7) cm H2O·L-1·s-1,P组皆低于N组(T1:P=0.004,T2:P=0.01,T3:P=0.005,T4:P=0.001),而Compl测量值在T3、T4两个时点P组为(30.2±3.5)、(29.9±3.6)ml/cm H2O,高于N组的(27.3±4.8)、(27.2±4.1) ml/cm H2O(T3:P=0.033,T4:P=0.031).与T0时比较,两组患者术中HR明显下降(P=0.000),SBP、DBP、SpO2与T0时比较差异无统计学意义(P＞0.05). 结论 妇科腹腔镜手术术前应用盐酸戊乙奎醚可有效改善患者气腹后肺通气功能,降低气道阻力,提高肺顺应性,对血流动力学无明显影响.     

压力控制容量保证通气模式对全麻患者呼吸力学的影响

目的观察压力控制容量保证(PC-VG)通气模式对全麻患者呼吸力学的影响。方法择期行平卧位下腹部和盆腔剖腹手术全麻患者40例,随机分为两组,分别采用PC-VG模式(P组)和容量控制通气(VCV)模式(V组)行机械通气。记录气管插管后5min(T0)、15min(T1)、30min(T2)、60min(T3)、120min(T4)气道峰压(Ppeak)、气道平均压(Pmean)、气道平台压(Pplant)及肺顺应性(CL)和气道阻力(Raw)。结果与T0时比较,T1~T4时V组中Ppeak、Pmean、Pplant、Raw明显升高(P0.05或P0.01),两组CL均明显降低(P0.01),P组Raw明显升高(P0.05)。与V组比较,P组T1~T4时Ppeak、Pplant明显降低(P0.05),T4时P组CL明显升高(P0.05)。结论 PC-VG模式对全麻患者呼吸力学影响较小。     

不同通气模式对老年患者腹腔镜结直肠手术呼吸参数的影响

目的观察小潮气量容量控制通气(VCV)联合呼气末正压通气(PEEP)和压力控制通气(PCV)联合PEEP对老年患者呼吸参数的影响。方法选择行腹腔镜直肠、乙状结肠手术患者51例,男25例,女26例,年龄65~80岁,BMI 18~30kg/m2,ASAⅠ或Ⅱ级,随机分为两组:VP组(VCV+PEEP)和PP组(PCV+PEEP),每组25例。气腹期间VP组以VT6 ml/kg+5cmH2O PEEP模式通气,PP组将VT设为6 ml/kg通气3 min后切换为PCV并加用5cmH2O PEEP进行通气。记录气管插管VCV通气5min(T1)、建立人工气腹5 min(T2)、建立人工气腹35min(T3)、建立人工气腹65min(T4)、手术结束(T5)、拔管前(T6)时VT、动态肺顺应性(Cdyn)、RR、气道峰压(Ppeak)、气道平台压(Pplat)和PETCO2。记录T1、T3、T4和离开PACU(T7)时PaO2、PaCO2,并计算肺泡-动脉血氧分压差(PA-aDO2)、氧合指数(OI)、呼吸指数(RI);记录术后5d内肺部并发症(PPCs)情况。结果与VP组比较,T2-T4时PP组VT明显升高、Cdyn明显增大(P0.05),T3-T5时PP组RR明显减慢(P0.05),T2-T5时PP组Ppeak和Pplat明显降低(P0.05),T4时PP组PETCO2和PA-aDO2明显降低、PaO2明显升高、RI明显减小、OI明显增大(P0.05)。术后随访两组患者PPCs差异无统计学意义。结论PCV联合PEEP通气模式明显降低Ppeak和Pplat、增高VT和增大Cdyn,同时明显改善气腹65min时肺氧合功能,所以老年患者腹腔镜结直肠手术术中应优先考虑使用。     

靶控平均动脉压对老年患者腹腔镜术后肺功能的影响

目的 通过术中靶控MAP观察老年患者在腹腔镜胆囊切除术后肺功能的变化.方法 将40例老年患者随机分对照组（基础血压控制±30％范围）和靶控组（将MAP靶控在80 ～100 mmhg范围）,每组20例.分别在气腹前5 min （T1）、气腹后5 min（T2）、气腹放气后5 min（T3）,记录潮气量（VT）、平均动脉压（MAP）、气道峰压（Ppeak）、气道压力平台压（Pp1at）、呼气末二氧化碳（PETCO2）、动脉血氧分压（PaO2）、动脉血二氧化碳分压（PaCO2）.并根据公式计算静态肺顺应性（Cstat）、动态肺顺应性（Cdyn）、氧合指数、肺内分流率（Qs/Qt）.结果 与正常组相比,靶控组在T2时刻的MAP、Ppeak、Pplat、降低,而Cstat、Cydn升高（P＜0.05）,在T1、T2时刻比较,差异无统计学意义（P＞0.05）.两组氧合指数、Qs/Qt比值在T1、T2、T3时刻比较,差异均无统计学意义（P＞0.05）.结论 术中靶控MAP可提高老年患者的肺顺应性,对肺功能有一定的保护作用.     

小潮气量联合低水平呼气末正压通气策略在妇科腹腔镜手术麻醉中的应用

目的观察小潮气量联合低水平呼气末正压通气策略应用于妇科腹腔镜手术的效果。方法随机将40例妇科腹腔镜手术患者均分为常规机械通气组(Ⅰ组)和小潮气量联合低水平PEEP通气组(Ⅱ组)。Ⅰ组新鲜气体流量2 L/min,VT 8 m L/kg,吸呼比1∶2。Ⅱ组新鲜气体流量2 L/min,VT 6 m L/kg,吸呼比为1∶2,PEEP 5 cm H2O。调整通气频率,维持PETCO235~45 mm Hg。于插管后5 min(T1)、气腹30 min(T2)和气腹结束后5 min(T3)时记录气道峰压(Ppeak)、气道平台压(Pplat)、动态肺顺应性(Cdyn)和气道阻力(Raw),并计算肺泡-动脉血氧分压差(A-a DO2)、氧合指数(Pa O2/Fi O2)、呼吸指数(RI)和死腔率(VD/VT)。记录拔管时间、术后48h内呼吸并发症发生情况和住院时间。结果与Ⅰ组比较,Ⅱ组T2时Ppeak和Pplat、T1、2时Raw降低,T2时Cdyn升高,T1~3时Pa O2/Fi O2升高(P0.05),RI、VD/VT和A-a DO2降低(P0.05)。2组各时点动脉血p H值、拔管时间、住院时间无显著差异(P0.05。Ⅱ组术后48 h内呼吸并发症发生率降低(P0.05)。结论小潮气量(6 m L/kg)联合低水平PEEP(5 cm H2O)通气是妇科腹腔镜手术麻醉较适宜的呼吸管理模式。     

肺保护性通气在老年患者腹腔镜子宫内膜癌根治术中的应用

目的探讨肺保护性通气在老年患者腹腔镜子宫内膜癌根治术中的应用效果。方法选择2019年6月至2020年6月择期行腹腔镜子宫内膜癌根治术的老年女性患者60例,年龄65～80岁,BMI 20～28 kg/m~2,ASAⅠ或Ⅱ级。采用随机数字表法将患者分为两组:肺保护性通气组(P组)和常规机械通气组(R组),每组30例。P组设置V_T 7 ml/kg、呼气末正压通气(PEEP) 7 cmH_2O、每30分钟规律手法肺复张一次;R组仅设置V_T 9 ml/kg,未采用PEEP和肺复张。记录气腹前即刻、气腹后2 h、手术结束即刻的气道峰压(Ppeak)、气道平台压(Pplat)、肺动态顺应性(Cdyn)及血清IL-6、IL-8、TNF-α浓度。记录气腹前即刻和出复苏室即刻的氧合指数(PaO_2/FiO_2)。结果与气腹前即刻比较,气腹后2 h、手术结束即刻两组Pplat、Ppeak及血清IL-6、IL-8、TNF-α浓度均明显升高(P0.05),Cdyn明显降低(P0.05);出复苏室即刻两组PaO_2/FiO_2明显降低(P0.05)。与R组比较,P组气腹后2 h、手术结束即刻Pplat、Ppeak及血清IL-6、IL-8、TNF-α浓度明显降低(P0.05),Cdyn明显升高(P0.05);出复苏室即刻PaO_2/FiO_2明显升高(P0.05)。结论肺保护性通气可以减轻老年患者腹腔镜子宫内膜癌根治术围术期呼吸功能损伤和炎症反应,可安全用于老年患者腹腔镜子宫内膜癌根治术。     

静脉注射盐酸戊乙奎醚对腹腔镜手术患者呼吸功能的影响

目的:评价气腹前静脉注射盐酸戊乙奎醚对腹腔镜胆囊手术患者呼吸功能的影响。方法:择期全麻下拟行腹腔镜胆囊手术患者50例,ASA分级Ⅰ或Ⅱ级,年龄35～64岁,采用随机数字表法,将患者随机分为两组(n=25)静脉注射盐酸戊乙奎醚组:气腹前15mi n静脉注射盐酸戊乙奎醚1mg(用生理盐水稀释至2ml)和对照组:静脉注射等容量生理盐水。麻醉诱导:两组均TCI异丙酚(血浆靶浓度3μg/ml),静脉注射瑞芬太尼1μg/kg和顺苯阿曲库铵0.15mg/kg行气管插管。麻醉维持:TCI异丙酚,血浆靶浓度为2μg/ml,TCL瑞芬太尼(血浆靶浓度2～4ng/kg),静脉输注顺阿曲库铵1.2ug.kg-1`.mi n-1。维持BIS45-50。分别于气腹前15mi n给药前即刻(T0)、气腹后即刻(T1)、气腹15mi n(T2)和气腹放气后15mi n(T3)时记录肺动态顺应性、气道峰压和监测血气指标。结果:与T0比较,戊乙奎醚组T1-3时肺动态顺应性(Cd)及气道峰压(Ppeak)差异均无统计学意义(P>0.05),而对照组T1-2时Cd降低,Ppeak升高(P<0.05),于T3与时恢复至T0水平(P>0.05),两组PETCO2升高(P<0.05);与对照组比较,戊乙奎醚组T1-2时Cd升高,Ppeak降低(P<0.05)。结论:在腹腔镜胆囊手术中,气腹前静脉注射盐酸戊乙奎醚可改善二氧化碳人工气腹引起的气道压升高和肺顺应性降低,增加气道通气功能。     

选择性肺叶隔离通气用于COPD老年患者开胸手术时的通气效果

目的 评价选择性肺叶隔离通气用于慢性阻塞性肺病(COPD)老年患者开胸手术时的通气效果.方法 择期拟行食管癌根治术合并COPD的老年患者30例,年龄65～80岁,体重指数16～ 28 kg/m2,ASA分级Ⅱ或Ⅲ级,采用随机数字表法,将其随机分为2组(n=15):单肺通气组(OLV组)和选择性肺叶隔离通气组(SLC组).OLV组患者采用双腔气管导管实施单肺通气,SLC组患者使用支气管堵塞器堵塞肺叶支气管,实施选择性肺叶隔离通气.于平卧位双肺通气10 min(T0)、侧卧位单肺通气或选择性肺叶隔离通气5 min(T1)、45 min(T2)、90 min(T3)、术毕侧卧位双肺通气10 min(T4)时测定气道峰压(Ppeak)、气道平台压(Pplat)、气道阻力(Raw)和动态肺顺应性(Cd).于T0、T3、T4时采集动脉血样,行血气分析,计算氧合指数(OI)、肺泡-动脉血氧分压差[P(A-a)Q2]和呼吸指数(RI).结果 与OLV组比较,SLC组T2～4时Peak、Pplat及Raw降低,T1～4时Cd升高,T3,4时0I升高、P(A-a)O2和RI降低(P＜ 0.05或0.01).结论 COPD老年患者胸科手术时,单肺通气和选择性肺叶隔离通气均可安全完成手术,实施肺叶隔离通气能改善氧合,具有更好的通气效果.     

麻醉诱导期开始采用肺保护性通气策略对妇科腔镜手术患者氧合及预后的影响

目的探讨从麻醉诱导期开始采用肺保护性通气策略对妇科腔镜手术患者氧合及预后的影响。方法选择在本院接受妇科腹腔镜手术的患者60例,随机分为三组,每组20例。采用间歇正压通气(IPPV)模式,氧浓度为100%,氧气流量2 L/min,吸呼比为1∶2。A组:从诱导期(即自主呼吸消失后,予面罩机械通气5 min)开始全程通气模式:VT6 ml/kg,RR 16次/分,PEEP为5cm H2O,每30分钟给予一次手法肺复张(手控通气,气道压力维持40 cm H2O,持续30 s);B组:诱导期通气模式:VT10 ml/kg,RR 10次/分,插管后通气模式:VT6 ml/kg,RR 16次/分,PEEP 5cm H2O,每30分钟给予一次手法肺复张;C组:全程通气模式均为VT10 ml/kg,RR 10次/分。记录插管前(T0)、气腹后(T1)、手术开始30 min(T2)、60 min(T3)、放气腹(T4)时的气道峰压(Ppeak)、平均气道压(Pmean)、计算肺顺应性(CL),并在T0、T1、T3、清醒拔管后吸空气5 min(T5)时抽取动脉血进行血气分析,计算氧合指数(OI)及肺内分流率(Qs/Qt)。记录患者术后并发症发生情况与住院天数。结果与T0时比较,T1~T4时三组Ppeak和Pmean均明显升高,C组Ppeak明显高于A组和B组(P0.05),T2时C组Pmean明显高于A组和B组(P0.05);三组CL在气腹后明显降低(P0.05),T3和T4时C组明显低于A组和B组(P0.05);三组PETCO2在气腹后明显升高,T2~T4时C组明显低于A组与B组(P0.05),A组与B组差异无统计学意义;三组OI随着时间延长变化差异无统计学意义,拔管后三组均明显降低(P0.05);三组Qs/Qt随着手术进行呈上升趋势,与T0时比较,三组在T3时明显上升(P0.05),C组明显大于A组和B组(P0.05);T5时均明显下降(P0.05)。术后仅C组有1例发生肺部感染。结论与常规通气相比,对接受妇科腔镜手术患者采用保护性肺通气策略能够明显改善患者的肺顺应性和氧合功能,有利于肺保护。     

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.     

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.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.