改良Weaver-Dunn法结合锁骨钩钢板内固定治疗TossyⅢ型肩锁关节脱位的病例对照研究

目的:对比锁骨钩钢板内固定术与改良Weaver-Dunn法联合锁骨钩钢板内固定术治疗TossyⅢ型肩锁关节脱位的临床疗效。方法:回顾性分析2012年1月至2014年1月手术治疗的41例新鲜TossyⅢ型肩锁关节脱位患者的临床资料,按其手术方式分为锁骨钩钢板内固定术(A组)和改良Weaver-Dunn法联合锁骨钩钢板内固定术(B组).A组21例,男15例,女6例,年龄17～51 岁,平均(31.60±12.58)岁,术前Constant-Murley评分40.25±9.80,采用锁骨钩钢板内固定术;B组20例,男13例,女7例,年龄18～48 岁,平均(29.40±11.27)岁,术前Constant-Murley评分41.45±8.81,采用改良Weaver-Dunn法联合锁骨钩钢板内固定术。比较两组患者的手术时间、术中出血量、手术前后影像学变化、术后并发症,分别于术后3、6、12个月时,采用Constant-Murley评分进行疗效评价。结果:A组手术时间(40.50±24.36) min,术中出血量(75.30±30.36) ml; B组手术时间(60.10±23.55) min,术中出血量(100.70±40.12) ml;A组21例获随访,时间12～18 个月,平均(14.8±3.1)个月; B组20例获随访,时间12～14 个月,平均(13.6±1.5)个月。两组手术时间、术中出血量比较差异有统计学意义。两组随访时间比较差异无统计学意义。术后A组6例出现并发症,B组3例,两组比较差异无统计学意义。术后6个月时,A组Constant-Murley评分为88.85±4.23,B组为92.15±3.82,两组比较差异有统计学意义(t=-2.56,P=0.022<0.05);其余各时间点比较差异无统计学意义。结论:锁骨钩钢板内固定术与改良Weaver-Dunn法联合锁骨钩钢板内固定术均是治疗TossyⅢ型肩锁关节脱位的有效手术方法。锁骨钩钢板内固定术较改良Weaver-Dunn法联合锁骨钩钢板内固定术创伤小,但改良Weaver-Dunn法联合锁骨钩钢板内固定术重建的喙锁韧带更牢固,且能早期取出锁骨钩钢板,可以更早地改善患者的肩关节功能。     

Endobutton带袢钛板与钩钢板治疗肩锁关节脱位的病例对照研究

目的：比较Endobutton带袢钛板与锁骨钩钢板治疗肩锁关节脱位的临床疗效及并发症。方法：回顾性2015年3月至2019年5月手术治疗的Rockwood Ⅲ-Ⅴ型肩锁关节脱位患者48例,按照手术方法不同分为两组。其中23例采用Endobutton带袢钛板固定治疗（观察组）,男15例,女8例;年龄23~59（36.2±8.1）岁;Rockwood Ⅲ型6例,Ⅳ型11例,Ⅴ型6例。25例采用锁骨钩钢板治疗（对照组）,男17例,女8例;年龄22~54（34.7±6.4）岁;Rockwood Ⅲ型6例,Ⅳ型14例,Ⅴ型5例。比较两组患者手术时间,术中出血量,住院天数,疼痛视觉模拟评分（visual analogue scale,VAS）,肩关节功能Connstant-Murley评分及术后并发症情况。结果：两组患者术后均获得随访,时间24~51（30.5±6.5）个月。观察组术中出血量、住院天数分别为（71.9±4.0） ml,（8.2±1.6） d;对照组分别为（97.6±13.4） ml,（12.8±1.2） d;两组比较差异有统计学意义（P<0.05）。两组手术时间比较差异无统计学意义（P>0.05）。观察组术后即刻、术后12个月VAS评分分别为（4.00±0.39）、（1.58±0.13）分,与对照组（7.32±0.43）、（3.09±0.23）分比较差异有统计学意义（P<0.05）;观察组术后即刻、术后12个月肩关节功能Connstant-Murley评分为（59.65±0.15）、（85.97±0.73）分,与对照组（52.77±0.19）、（55.78±0.19）分比较差异有统计学意义（P<0.05）。观察组发生肩部疼痛1例,异位骨化1例;对照组发生内固定失败1例,肩峰撞击3例,肩部疼痛3例,异位骨化3例;两组比较差异有统计学意义（P<0.05）。结论：Endobutton带袢钛板内固定技术相比锁骨钩钢板内固定治疗肩锁关节脱位,具有手术出血少、住院天数短、术后疼痛轻、肩关节功能恢复好、并发症少等优势。     

双纽扣钢板联合加强锚钉治疗肩锁关节脱位

目的: 探讨双纽扣钢板联合加强锚钉技术与锁骨钩钢板内固定治疗完全性肩锁关节脱位的疗效及预后。方法: 选取2017年7月至2020年9月收治的手术治疗肩锁关节脱位患者42例为研究对象,分为观察组（21例）和对照组（21例）。观察组中,男14例,女7例;年龄21~63（45.05±8.70）岁;对照组中,男16例,女5例;年龄25~68（45.00±9.44）岁。观察组行双纽扣钢板联合加强锚钉技术治疗,对照组行锁骨钩钢板内固定术治疗。比较两组患者手术时间、术中出血量、术后住院时间,术前及术后1、3、6个月肩关节疼痛视觉模拟评分（visual analogue scale,VAS）,肩关节功能Constant-Murley评分以及术后并发症发生情况。结果: 两组术中出血量及术后住院时间比较,差异无统计学意义（P>0.05）;双纽扣钢板联合加强锚钉技术组手术时间（65.24±5.36）min,较锁骨钩钢板组（48.81±4.72） min长（P<0.05）。肩关节功能及疼痛程度测定显示,术前两组差异无统计学意义（P>0.05）;术后1、3、6个月,观察组Constant-Murley评分分别为（73.29±2.15）、（85.43±1.47）、（93.86±1.24）分,与对照组比较差异有统计学意义;VAS评分为（2.76±0.62）、（1.71±0.64）、（0.57±0.51）分,与对照组比较,差异有统计学意义（P<0.05）。观察组术后1例肩部疼痛;对照组术后5例肩部疼痛,2例肩关节活动受限,1例肩峰下骨质吸收,两组均未出现复位丢失。结论: 双纽扣钢板联合加强锚钉治疗完全性肩锁关节脱位能够获得良好的临床效果,无须取出内固定,患者肩关节功能恢复情况及疼痛改善情况优于锁骨钩钢板内固定术,更值得临床推广。     

Endobutton钢板与改良Weaver-Dunn联合锁骨钩钢板治疗Rookwood Ⅲ型肩锁关节脱位的近期临床疗效观察

目的 比较Endobutton钢板与改良Weaver-Dunn联合锁骨钩钢板治疗Rookwood Ⅲ型肩锁关节脱位的近期临床疗效。方法 回顾性分析我院骨科2016年1月至2017年6月分别采用Endobutton钢板与改良Weaver-Dunn联合锁骨钩钢板治疗的54例Rookwood Ⅲ型肩锁关节脱位病人的资料,根据治疗方法不同分为Endobutton组（30例）和Weaver-Dunn组（24例）,对两组手术时间、术中出血量、住院时间、恢复工作时间进行对比;分别采用肩关节Constant-Murley评分、疼痛视觉模拟量表（visual analogue scale, VAS）评分比较两组术前、术后3个月、术后6个月、术后1年的肩关节功能恢复及疼痛改善情况。结果 两组术后均未出现内固定断裂、切口感染及血管损伤,术后总并发症比较差异无统计学意义（χ²=1.752,P=0.237）;Endobutton组的手术时间、术中出血量、住院时间、恢复工作时间均低于Weaver-Dunn组,差异均有统计学意义（P均＜0.05）;Endobutton组和Weaver-Dunn组术后3个月、术后6个月、术后1年Constant-Murley各项评分：疼痛、日常活动、患手最大位置、力量测试、肩外展、肩前屈、肩外旋、肩内旋及VAS评分与术前比较,差异均有统计学意义（P均＜0.05）;术后3个月、术后6个月及术后1年,Endobutton组Constant-Murley各项评分及VAS评分均优于Weaver-Dunn组,差异均有统计学意义（P均＜0.05）。结论 Endobutton钢板和改良Weaver-Dunn联合锁骨钩钢板均能恢复Rookwood Ⅲ型肩锁关节脱位病人的肩关节功能,但前者近期临床疗效更具有优势。     

双Endobutton钢板重建喙锁韧带联合Ⅰ期肩锁韧带修复治疗Ⅲ度以上肩锁关节脱位

目的:探讨双Endobutton钢板联合Ⅰ期肩锁韧带修复治疗Ⅲ度以上肩锁关节脱位的临床疗效。方法:自2010年1月至2013年9月, 手术治疗56例RockwoodⅢ度以上肩锁关节脱位的患者, 其中男20例, 女36例;年龄32～52岁, 平均38.5岁;左侧25例, 右侧31例;受伤至手术时间3～14 d,平均7 d.术前均诊断为肩锁关节脱位(RockwoodⅢ度以上),手术采用双Endobutton钢板进行喙锁韧带重建, 同时行带线金属骨锚钉修复肩锁韧带。观察患者术后并发症情况, 并采用Karlsson评定标准及Constant-Murley评分进行肩关节功能评定。结果:所有患者获得随访, 时间8～24个月, 平均11个月。术后6个月随访时根据Karlsson评定标准A级42例, B级13例, C级1例。Constant-Murley肩关节功能总分由术前的(42.80±5.43)分提高至术后6个月的(91.75±4.27)分。术后6个月各项评分均优于术前(P<0.05),其中优48例, 良7例, 差1例。所有患者随访期间均未出现肩关节粘连, 钢板螺钉松动、断裂。结论:双Endobutton钢板重建喙锁韧带联合Ⅰ期肩锁韧带修复治疗Ⅲ度以上肩锁关节脱位早期临床疗效满意, 有利于肩关节功能早期恢复。     

钩钢板钩端深度与肩峰高度的差值对术后发生肩峰下撞击综合征的影响

目的 探讨钩钢板钩端深度与肩峰高度的差值对术后发生肩峰下撞击综合征（subacromial impingement syndrome,SIS）的影响。方法 回顾性分析2018年3月至2020年3月我院收治的113例使用锁骨钩钢板治疗肩锁关节脱位的病人,根据术后是否出现SIS分为两组,SIS阳性组25例,男17例,女8例,年龄为（30.24±6.98）岁（19~48岁）,左侧11例,右侧14例;SIS阴性组88例,男49例,女39例,年龄为（33.24±9.27）岁（21~54）岁,左侧31例,右侧57例。基于冠状面CT测量病人的肩峰高度,记录病人所用钩钢板的钩端深度,并计算两者的差值。结果 SIS阳性组与SIS阴性组的肩峰高度比较,差异无统计学意义（t=0.545,P=0.587）。SIS阳性组钩钢板的钩端深度与肩峰高度的差值为（8.063±1.150） mm（5.5~10.4 mm）,SIS阴性组的差值为（6.715±1.820） mm（3.68~10.16 mm）,差异有统计学意义（t=3.384,P=0.001）。钩钢板钩端深度与肩峰高度的差值＞6 mm的病人中SIS的发生率（29.11%）与差值≤6 mm的病人中SIS的发生率（5.88%）比较,差异有统计学意义（t=7.446,P=0.006）。结论 锁骨钩钢板的钩端深度与肩峰高度的差值大于6 mm可能是锁骨钩钢板术后发生SIS的影响因素。术前测量肩峰高度可以对术中选择钩钢板的型号提供建议。     

带袢钢板重建喙锁韧带与锁骨钩钢板内固定治疗Rockwood Ⅲ～Ⅴ型肩锁关节脱位的比较

目的 比较带袢钢板重建喙锁韧带与锁骨钩钢板内固定治疗Rockwood Ⅲ～Ⅴ型肩锁关节脱位对患者肩关节活动度、肩关节功能的影响。方法 纳入自2018-01—2021-01诊治的76例Rockwood Ⅲ～Ⅴ型肩锁关节脱位,其中40例采用带袢钢板重建喙锁韧带治疗（带袢钢板组）,36例采用锁骨钩钢板内固定治疗（锁骨钩钢板组）。比较两组术后6个月肩关节功能Constant-Murley评分、末次随访时肩关节活动度、并发症发生情况。结果 76例均获得随访,随访时间平均8.4(6～12)个月。带袢钢板组出现1例（2.5%）并发症（喙锁韧带骨化）,锁骨钩钢板组出现6例（16.7%）并发症（3例喙锁韧带骨化,2例肩峰撞击综合征,1例肩锁关节骨性关节炎）,带袢钢板组并发症发生率低于锁骨钩钢板组,差异有统计学意义（P<0.05）。带袢钢板组术后6个月肩关节功能Constant-Murley评分高于锁骨钩钢板组,末次随访时肩关节外展上举活动度、前屈上举活动度均大于锁骨钩钢板组,差异有统计学意义（P<0.05）。结论 带袢钢板重建喙锁韧带治疗Rockwood Ⅲ～Ⅴ型肩锁关节脱位的疗效优于锁骨钩...     

TightRope重建喙锁韧带联合锚钉修复肩锁关节治疗 肩锁关节脱位的临床疗效

目的 探讨TightRope重建喙锁韧带联合锚钉修复肩锁关节治疗肩锁关节脱位的疗效。方法 回顾性分析2013年5月至2015年5月采用TightRope重建喙锁韧带联合锚钉修复肩锁关节手术治疗的13例肩锁关节脱位患者的资料及采用肩锁钩钢板治疗的21例肩锁关节脱位患者的资料,比较两组患者的手术时间、术中出血量、术后及末次随访时的X线片及术后3、6个月及末次随访时Neer肩关节功能评分。结果 TightRope联合锚钉组和肩锁钩钢板组平均手术时间分别为51.0±9.5 min、48.0±8.3 min,术中出血量分别为84.5±11.1 ml、80.4±9.8 ml,差异均无统计学意义（P >0.05）,在术后3个月、6个月及末次随访时,TightRope联合锚钉组Neer肩关节功能评分为84.5±8.1、 91.8±9.4、96.1±11.1,肩锁钩钢板组Neer肩关节功能评分为72.4±7.5、 86.9±9.6、89.2±9.8,TightRope联合锚钉组明显优于肩锁钩钢板组,差异有统计学意义（P <0.05）。末次随访时的X线片提示TightRope联合锚钉组患者无复位的丢失、创伤性关节炎等出现;肩锁钩钢板固定组4例患者出现肩峰下撞击征,2例患者取出钢板后出现复位的丢失,1 例患者发生肩峰骨溶解,所有患者均在8~10个月二次手术取出内固定。结论 采用TightRope重建喙锁韧带联合锚钉修复肩锁关节治疗肩锁关节脱位,可获得更符合生物力学的复位,肩锁关节稳定,肩关节功能恢复满意,无需二次手术取出内固定。     

锁骨钩钢板在胸锁关节脱位治疗中的应用

目的:探讨应用锁骨钩钢板治疗胸锁关节脱位的方法及疗效。方法:2010年1月至2014年3月,采用锁骨钩钢板固定治疗胸锁关节脱位患者6例,其中男5例,女1例;年龄26～48岁,平均34岁;病程3～20 d.患者均为外伤后患侧胸锁关节肿胀、疼痛,患侧肩关节活动明显受限,经X线片及CT诊断为胸锁关节前脱位,根据Rockwood评分法对术后疗效进行评价。结果:所有患者术后切口愈合良好,外观美观;X线片显示胸锁关节脱位复位良好,钢板位置良好。6例患者均获随访,时间4～18个月,平均12个月。根据Rockwood评分法进行疗效评定:优4 例,良 1 例,可 1 例,未见内固定失效及再脱位,无血管、神经及胸膜等副损伤。结论:锁骨钩钢板能在复位固定胸锁关节的同时保留胸锁关节微动功能,且不损伤胸锁关节软骨面。手术安全性高,固定效果好,患者术后可进行早期康复锻炼。     

关节镜下重建喙锁韧带并修复肩锁韧带治疗Rockwood Ⅲ型肩锁关节脱位

目的 探讨关节镜下重建喙锁韧带并修复肩锁韧带治疗RockwoodⅢ型肩锁关节脱位的临床疗效.方法 对我科2011年3月至2016年8月收治的60例RockwoodⅢ型肩锁关节脱位病人进行回顾性分析.其中男34例,女26例;左肩36例,右肩24例.年龄为23～48岁,平均年龄为(29.3±6.2)岁.受伤至手术时间为3～12 d,平均为(6.1±2.5)d.根据手术方法不同分为两组:修复组30例,使用关节镜下Endobutton技术重建喙锁韧带,采用5#爱惜帮聚酯纤维缝线修复肩锁韧带;对照组30例,使用关节镜下Endobutton技术重建喙锁韧带,不修复肩锁韧带.比较两组病人术后1年的肩锁关节前后位X线片的喙锁间隙数值以及术后1年的Constant-Murley肩关节功能评分.结果 随访时间为14～24个月,平均为(16±2.7)个月.所有病人手术切口均一期愈合,愈合时间为14～18 d,平均为(13±3.8)d,均无血管神经损伤.术后1年,修复组的喙锁间隙数值为(12.9±0.6)mm,优于对照组的(13.6±1.1)mm;修复组的Constant-Murley肩关节功能评分总分为(91.1±2.4)分,优于对照组的(86.3±3.5)分;上述指标组间差异均有统计学意义(P均<0.05).结论 关节镜下应用Endobutton技术重建喙锁韧带同时修复肩锁韧带治疗RockwoodⅢ型肩锁关节脱位,有利于肩锁关节稳定性及肩关节功能的恢复.     

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 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.     

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.     

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.     

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.     

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.     

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.