右美托咪定和帕瑞昔布钠预防腰椎术后躁动的比较

[目的]比较右美托咪定和帕瑞昔布钠对全麻下行腰椎手术患者苏醒期躁动的预防作用,探讨患者术后预防躁动的合理化用药方案.[方法]全麻下择期行腰椎手术的ASA Ⅰ或Ⅱ患者40例,随机分为两组:右美托咪定组(Y组)和帕瑞昔布钠组(P组),两组分别在手术结束前10 min给予静脉泵注右美托咪定0.5μg/kg和帕瑞昔布钠40 mg.记录两组患者用药前T1,拔管后1 min (T2)和拔管后5 min(T3)的血压和心率,并对两组患者的呼吸恢复时间、拔管时间、麻醉后恢复室(PACU)停留时间以及患者躁动情况进行记录.[结果]帕瑞昔布钠组(P组)在T2、T3时的HR和MAP比T1高,比右美托咪定组(Y组)也高;Y组2例出现躁动,P组5例出现躁动.[结论]右美托咪定预防腰椎手术后躁动比帕瑞昔布钠更有效,且右美托咪定使病人在苏醒期的血流动力学更稳定.     

右美托咪定与帕瑞昔布钠对腹腔镜下子宫肌瘤切除术患者机械痛阈值及苏醒期躁动控制效果

目的评价右美托咪定与帕瑞昔布钠定对腹腔镜下子宫肌瘤切除术患者机械痛阈值及苏醒期躁动控制效果。方法选取接受腹腔镜下子宫肌瘤切除术的患者为研究对象,累计162例。随机分为A组右美托咪定组,B组帕瑞昔布钠组,C组对照组,各组54例。患者均采用丙泊酚与瑞芬太尼复合麻醉。A组与B组在气腹建立前分别给予右美托咪定0. 5μg/kg、帕瑞昔布钠40mg静脉输注。结果 A组与B组在手术及苏醒后心率与平均动脉压稳定性高于C组,术后4、8、12及24小时机械痛阈值均高于C组(P0.05),且24小时A组高于B组(P=0.035)。拔管时A组与B组Riker评分显著低于C组(P0.05),两两比较结果显示,A组评分低于B组(P=0.004);A组、B组与C组术后躁动的发生率分别为7.4%、12.9%与24.1%,统计学差异显著(χ2=6.163,P=0.046)。拔管前、拔管后20分钟A组与B组血清褪黑素平均水平显著高于C组(P0.05),且A组高于B组(P0.05)。结论右美托咪定与帕瑞昔布钠均可有效控制腹腔镜下子宫肌瘤切除术患者术后疼痛,减少躁动的发生,且右美托咪定可具有更好的临床效果。     

右美托咪定复合帕瑞昔布钠对腹腔镜胆囊切除术后疼痛的影响

目的观察右美托咪定复合帕瑞昔布钠对腹腔镜胆囊切除术后疼痛的影响。方法择期腹腔镜胆囊切除手术患者45例,随机均分为三组:右美托咪定复合帕瑞昔布钠组(DP组)、帕瑞昔布钠组(P组)和对照组(C组)。术前30min DP组静注右美托咪定0.5μg/kg和帕瑞昔布钠20mg;P组静注帕瑞昔布钠40mg;C组静注5ml生理盐水。监测并记录入室时、插管即刻、气腹5min、气腹30min、拔管即刻的MAP和HR,记录丙泊酚和瑞芬太尼用量、苏醒时间、拔管时间、恶心、呕吐发生率和患者满意度。并记录术后2h(T1)、6h(T2)、12h(T3)、24h(T4)静态、动态(剧烈咳嗽或突然翻身时)疼痛数字等级评分(numerical rating scale,NRS)和Ramsay镇静评分。结果入室时、插管即刻、气腹5min、气腹30min、拔管即刻时三组患者MAP、HR差异无统计学意义。三组患者丙泊酚、瑞芬太尼用量、苏醒时间和拔管时间差异均无统计学意义。与C组比较,T1~T3时DP组和P组静态NRS评分明显降低(P0.05);T1~T4时DP组和T1、T2时P组动态NRS评分明显降低(P0.05)。与DP组比较,T1、T2时P组和C组Ramsay镇静评分明显降低(P0.05)。DP组2例需用阿托品,1例需用麻黄碱;P组1例需用阿托品,1例患者麻黄碱;C组2例NRS评分≥7分,肌注盐酸布桂嗪100mg后NRS评分≤5分,1例需用阿托品,2例需用麻黄碱。与DP组比较,P组和C组满意度明显降低(P0.05)。三组患者恶心、呕吐发生率差异无统计学意义。结论术前30min静注帕瑞昔布钠20mg复合0.5μg/kg右美托咪定减轻腹腔镜胆囊切除术后急性疼痛,效果优于单用帕瑞昔布钠。     

右美托咪定对扁桃体摘除术麻醉苏醒期躁动的影响

目的 评价右美托咪定对扁桃体摘除术患者麻醉苏醒期躁动的影响.方法 择期扁桃体摘除术患者60例,年龄12～20岁,体重35～65 kg,ASA Ⅰ或Ⅱ级,随机均分为两组.麻醉诱导后,右美托咪定组(D组)在10 min内静脉泵注右美托咪定1.0μg/kg(用生理盐水稀释至50 ml),然后以0.5μg,kg-1·h-1持续泵入至手术结束前20 min.对照组(C组)以同样方式泵注生理盐水.术中吸入异氟醚和静注丙泊酚维持麻醉.记录吸痰拔管时镇静躁动(SAS)评分及拔管后10 min的Ramsay镇静评分及VAS评分.结果 D组阿托品使用次数明显多于C组(P＜0.05).拔管时D组SAS评分明显低于C组,而Ramsay评分明显高于C组(P＜0.05).结论 右美托咪定可明显减少扁桃体摘除术患者麻醉苏醒期闻躁动的发生.     

右美托咪定复合氟哌利多对七氟醚全麻胸科手术老年患者苏醒期躁动的影响

目的评价右美托咪定复合氟哌利多治疗七氟醚全麻胸科手术老年患者苏醒期躁动的有效性及安全性。方法选取七氟醚全麻下普胸外科术后严重躁动老年患者60例,男48例,女12例,年龄66～75岁,ASAⅡ或Ⅲ级,按照随机数字表分为三组:氟哌利多组(F组)、右美托咪定组(D组)和右美托咪定复合氟哌利多组(DF组)。被诊断为苏醒期严重躁动后,F组静脉推注氟哌利多0.06 mg/kg;D组右美托咪定1μg/kg泵注10 min,继以0.2μg·kg~(-1)·h~(-1)维持泵注1 h;DF组静脉推注氟哌利多0.03 mg/kg,同时给予右美托咪定0.5μg/kg泵注10 min,继以0.2μg·kg~(-1)·h~(-1)维持泵注1 h。观察并记录躁动评分、Ramsay镇静评分、PaCO_2变化以及恶心、呕吐等不良反应的发生情况。结果给药后5、10、15、20 min DF组躁动评分明显低于D组(P0.05);给药后60、90、120 min DF组躁动评分明显低于F组(P0.05)。给药后60、120 min三组PaCO_2差异无统计学意义。DF组和D组过度镇静比例明显低于F组(P0.05)。三组恶心、呕吐、心动过缓、高血压、低血压发生率差异无统计学意义。结论右美托咪定复合氟哌利多用于老年患者七氟醚全身麻醉苏醒期躁动的治疗效果确切,安全性好,可以规避右美托咪定不能快速推注同时避免氟哌利多导致过度镇静的缺点。     

帕瑞昔布钠对瑞芬太尼复合麻醉诱发患者术后痛觉过敏的影响

目的 探讨帕瑞昔布钠对瑞芬太尼复合麻醉诱发患者术后痛觉过敏的影响.方法 择期腹腔镜手术患者100例,性别不限,ASA分级Ⅰ或Ⅱ级,年龄21～64岁,体重50～80 kg,采用随机数字表法,将其随机分为5组(n=20):帕瑞昔布钠组(P组)、小剂量瑞芬太尼组(S组)、大剂量瑞芬太尼组(L组)、小剂量瑞芬太尼+帕瑞昔布钠组(SP组)和大剂量瑞芬太尼+帕瑞昔布钠组(LP组).P组、LP组和SP组麻醉前30 min时静脉注射帕瑞昔布钠40mg.依次静脉注射咪达唑仑、依托咪酯、顺阿曲库铵和瑞芬太尼(P组芬太尼)麻醉诱导.麻醉维持:S组和SP组静脉输注瑞芬太尼0.05μg· kg-1 ·min-1,L组和LP组静脉输注瑞芬太尼0.3μg·kg-1 ·min-1,各组均复合吸入七氟醚,静脉输注顺阿曲库铵.于术后30 min时采用数字评分法(NRS)评估静态和动态切口疼痛程度,术后镇痛的辅助措施采用静脉注射曲马多1.5 mg/kg,维持NRS评分≤5分.记录术后24h内曲马多使用情况和不良反应发生情况.结果 与P组比较,S组和L组术后30 min时静态和动态NRS评分升高,L组寒颤发生率和曲马多使用率升高(P＜0.05),SP组和LP组术后30 min时静态和动态NRS评分、不良反应发生率和曲马多使用率差异无统计学意义(P＞0.05);与S组比较,L组术后30min时静态和动态NRS评分、寒颤发生率和曲马多使用率升高,SP组术后30 min时静态和动态NRS评分降低(P＜0.05),不良反应发生率和曲马多使用率差异无统计学意义(P＞0.05);与L组比较,LP组术后30 min时静态和动态NRS评分、寒颤发生率和曲马多使用率降低(P＜0.05).结论 麻醉前30 min静脉注射帕瑞昔布钠40mg可抑制瑞芬太尼复合麻醉诱发患者术后痛觉过敏.     

右美托咪定用于气管异物患儿气管拔管的镇静效果

目的 观察术前给予右美托咪定对气管异物取出术患儿气管拔管的镇静效果.方法 气管异物取出术患儿60例,随机均分为两组,分别在全麻诱导前10 min内静脉输注右美托咪定0.5 μg/kg(D组)或生理盐水(C组).术中丙泊酚2mg·kg-1·h-1、瑞芬太尼0.1μg·kg-1·h-1维持麻醉.记录拔管前1 min、拔管时、拔管后1、5min时的HR、MAP、RR、Ramsay镇静评分的变化,以及拔管期间呛咳和躁动情况.结果 D组HR、RR、MAP、呛咳评分和躁动评分低于C组(P＜0.05),Ramsay镇静评分高于C组(P＜0.05).结论 术前给予右美托咪定可为气管异物患儿苏醒期提供较好的镇静,减少拔管期间躁动和呛咳.     

右美托咪定对上腹部手术后全麻苏醒期的影响

目的观察右美托咪定对上腹部手术全麻苏醒期的影响。方法上腹部手术患者32例,随机均分为右美托咪定组(D组)和生理盐水组(C组)。术后均行硬膜外镇痛,D组给予右美托咪定0.05~0.1μg·kg-1·h-1,根据镇静评分调整输注速度,C组泵注等量生理盐水。记录入PACU 5、30、60min MAP、HR、VAS评分、警觉/镇静评分(OAA/S评分);记录术后6h内镇痛不全(VAS评分5分)及寒颤、呼吸抑制、恶心呕吐和皮肤瘙痒不良反应发生率。结果两组患者入PACU后5、30、60min MAP、HR差异无统计学意义。与C组比较,入PACU后60min D组VAS评分明显降低(P0.01),OAA/S评分差异无统计学意义。与C组比较,术后6hD组镇痛不全、寒颤、恶心呕吐发生率明显降低(P0.01),皮肤瘙痒差异无统计学意义。两组均未发生镇静过度和呼吸抑制。结论右美托咪定辅助用于上腹部手术术后,减少寒颤,增加耐受性;降低氧耗,减少苏醒期不良反应。     

不同剂量右美托咪定预先给药对大鼠布比卡因心脏毒性的影响

目的评价不同剂量右美托咪定预先给药对大鼠布比卡因心脏毒性的影响。方法健康雄性SD大鼠48只,体重250~300g,采用随机数字表法,将其随机均分为四组:生理盐水对照组(C组)、右美托咪定5μg/kg组(D5组)、右美托咪定10μg/kg组(D10组)和右美托咪定15μg/kg组(D15组)。以肢体Ⅱ导联监测ECG,股动脉置管监测MAP,股静脉置管给药。D5、D10、D15组分别于布比卡因给药前15min时经股静脉分别泵注右美托咪定5、10和15μg/kg,C组给予等容量生理盐水。四组大鼠均泵注0.75%布比卡因2mg·kg-1·min-1。分别记录大鼠发生抽搐、心律失常及心脏停搏的时间和布比卡因的用量,并测定心肌组织布比卡因含量。结果与C组比较,D5、D10和D15组发生抽搐、心律失常和心脏停搏的时间明显延长(P0.05),布比卡因的用量及心肌布比卡因含量明显增加(P0.05);与D5组比较,D10和D15组发生抽搐、心律失常和心脏停搏的时间明显延长,布比卡因的用量及心肌布比卡因含量明显增加(P0.05);D10与D15组发生抽搐、心律失常和心脏停搏的时间、布比卡因的用量及心肌布比卡因含量差异无统计学意义。结论静脉内预先给予右美托咪定可明显提高布比卡因中毒剂量阈值,延迟布比卡因心脏毒性的发生时间,减轻大鼠布比卡因心脏毒性反应,且在一定剂量范围内呈剂量依赖性。     

右美托咪定持续静脉注射对甲状腺手术患者全麻恢复期的影响

目的观察不同剂量右美托咪定持续静注对甲状腺手术全麻恢复期患者的影响。方法全麻下行择期甲状腺手术患者120例,ASAⅠ或Ⅱ级,随机均分为四组:在手术开始前10min至术毕前20min,分别泵注生理盐水(C组)、右美托咪定0.2μg·kg-1·h-1(D2组)、0.5μg·kg-1·h-1(D1组)和0.7μg·kg-1·h-1(D3组)。记录四组患者拔管前和拔管后呛咳评分和镇静-躁动评分(SAS评分),拔管后5、10、30、60、120min时VAS、Ramsay镇静评分和围术期MAP、HR;记录自主呼吸恢复时间、睁眼时间、拔管时间、定向力恢复时间,并记录不良反应等情况及用药情况。结果与C、D1、D2组比较,拔管前和拔管后D3组呛咳评分明显降低(P0.05)。与C、D1组比较,拔管前和拔管后D2、D3组SAS评分明显降低(P0.05)。在全麻恢复过程中,D2、D3组MAP和HR基本平稳,不同程度低于其他组,以D3组效果更明显(P0.05)。与C、D1组比较,D2、D3组躁动、心动过速,D3组高血压发生率明显降低(P0.05),D3组心动过缓发生率、阿托品用量明显升高(P0.05)。与C组比较,D3组PONV、D2组高血压发生率明显降低(P0.05)。D3组七氟醚用量最低(P0.05),术后追加芬太尼量最少(P0.05)。结论持续静脉泵注右美托咪定0.5、0.7μg·kg-1·h-1能有效减少甲状腺手术全麻恢复期呛咳、躁动的发生,维持血流动力学稳定,且不影响苏醒。0.7μg·kg-1·h-1速率给药优于0.5μg·kg-1·h-1。     

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.     

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.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

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.     

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.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

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.     

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.