全髋关节置换术患者延迟出院的危险因素分析

目的分析全髋关节置换术患者延迟出院的危险因素。方法回顾性分析2015年1月至2018年7月择期行单侧全髋关节置换术患者的临床资料,包括性别、年龄、BMI、ASA分级、手术时间、麻醉方式、术中失血量、术中输液量、术中阿片类药物用量、术中血管活性药物用量、PACU停留时间、术后随访静息疼痛评分、术前住院时间、术前合并症、术后并发症及转归情况。根据术后住院时间将患者分为两组:正常出院组(术后住院时间≤14 d)和延迟出院组(术后住院时间>14 d),采用单因素和多因素Logistic回归分析影响延迟出院的因素。结果共纳入908例患者。单因素分析显示,与正常出院组比较,延迟出院组的年龄明显偏高,术中失血量明显增多,手术时间、PACU停留时间、术前住院时间明显延长,术前合并症、术后并发症明显增多(P<0.05)。Logistic回归分析显示,年龄≥70岁(OR=2.075,95%CI 1.287~3.346,P=0.003)、手术时间>3 h(OR=1.997,95%CI 1.181~3.375,P=0.010)、术中失血量≥800 ml(OR=2.898,95%CI 1.449~5.794,P=0.003)、PACU时间>60 min(OR=1.745,95%CI 1.064~2.859,P=0.027)、术前住院时间≥7 d(OR=1.805,95%CI 1.114~2.924,P=0.016)、术前有合并症≥2个(OR=2.912,95%CI 1.513~5.825,P=0.003)是导致患者延迟出院的独立危险因素。结论患者年龄、术中失血量、手术时间、PACU停留时间、术前住院时间及术前合并症是全髋关节置换术后出院延迟的独立危险因素,针对危险因素进行有效干预是缩短住院时间改善患者预后的重要策略。     

老年髋部骨折患者术后心血管并发症的危险因素分析

目的探讨老年髋部骨折患者住院期间术后新发心血管并发症的危险因素。方法回顾性分析本院骨科2005年1月至2015年12月收治的髋部骨折患者693例,男257例,女436例,年龄65~103岁,BMI 16.5~33.1 kg/m2,ASAⅡ~Ⅳ级,分别收集患者的人口学资料、术前合并症、卧床时间、手术方式、麻醉方法、手术时间和出血量,采用多因素Logistic回归模型分析老年髋部骨折患者住院期间术后新发心血管并发症的危险因素。结果 46例患者(6.64%)在住院期间发生术后心血管并发症,包括心绞痛25例(3.61%)、心律失常19例(2.74%)、心力衰竭5例(0.72%)、心肌梗死4例(0.58%)和心源性猝死2例(0.29%)。单因素分析显示,年龄、心脏疾病、脑血管疾病、高血压、糖尿病、肾功能不全和全麻方式是老年髋部骨折患者住院期间新发术后心血管并发症的相关危险因素(P0.05)。多因素Logistic回归分析显示年龄(OR=1.11,95%CI 1.06~1.17,P0.001)、心脏疾病(OR=1.98,95%CI 1.02~3.85,P=0.045)、脑血管疾病(OR=2.14,95%CI 1.06~4.32,P=0.033)、高血压(OR=2.61,95%CI 1.23~5.51,P=0.012)、糖尿病(OR=2.06,95%CI 1.04~4.09,P=0.039)和肾功能不全(OR=17.42,95%CI 3.69~82.80,P0.001)是髋部骨折患者住院期间术后新发心血管并发症的独立危险因素。结论年龄、心脏疾病、脑血管疾病、高血压、糖尿病和肾功能不全可作为老年髋部骨折患者住院期间新发心血管并发症的预警因素。     

全膝关节置换术后切口愈合不良危险因素研究

背景:全膝关节置换术后切口愈合不良是一种常见并发症,严重影响术后康复及患者满意度。目的:分析全膝关节置换术后切口愈合不良的危险因素。方法:回顾性分析2014年6月至2016年6月198例行单侧初次全膝关节置换术患者的临床资料。分析年龄、性别、"鸡尾酒"应用、原发病、糖尿病、高血压、术中止血带使用时间、体重指数(BMI)等因素对切口愈合不良的影响。结果:术后切口愈合不良13例,发生率为6.5%。Logistic回归分析显示糖尿病(OR=13.58,95%CI:2.35~78.65,P=0.004)、止血带时间偏长(OR=1.03,95%CI:1.01~1.05,P=0.047)、类风湿性关节炎(OR=12.53,95%CI:1.82~86.14,P=0.010)及肥胖(OR=12.98,95%CI:2.01~82.23,P=0.009)患者切口愈合不良的发生概率明显偏高,差异有统计学意义;而年龄(OR=1.01,95%CI:0.93~1.09,P=0.792)、性别(OR=2.30,95%CI:0.37~14.4,P=0.376)、高血压(OR=0.51,95%CI:0.09~2.96,P=0.451),"鸡尾酒"应用(OR=0.79,95%CI:0.23~2.77,P=0.714)的切口愈合不良发生率均无显著差异,不具有统计学意义。结论:类风湿性关节炎、糖尿病、肥胖及术中止血带使用时间较长是发生全膝关节置换术后切口愈合不良的危险因素。     

老年髋部骨折术后谵妄的危险因素分析

目的探讨引起老年髋部骨折患者术后谵妄(postoperative delirium,POD)的主要危险因素。方法回顾性分析2014年5月至2015年1月收治的老年髋部骨折且符合纳入及排除标准的患者289例(股骨转子间骨折157例、股骨颈骨折132例),根据是否出现POD分组,记录并比较两组患者的年龄、性别、骨折部位、术前并存病、受伤至手术时间、手术方式、麻醉方式、手术时间、术中出血量,采用多因素Logistic回归分析老年髋部骨折患者POD的危险因素,观察术后并发症的情况。结果单因素分析显示组间年龄(χ2=13.813,P=0.001)、术前并存病(χ2=19.281,P0.001)、受伤至手术时间(t=5.101,P=0.041)、麻醉方式(χ2=32.632,P0.001)差异有统计学意义。多因素Logistic回归分析示年龄70~80岁和80岁组POD发生率高于年龄70岁组,OR值为3.427(95%CI:1.584,7.415)和6.247(95%CI:1.965,19.862);受伤至手术时间≥7 d组POD发生率高于1~3 d组,OR值为14.279(95%CI:5.391,37.819);术前并存病≥3种组POD的发生率高于≤2种组,OR值为4.069(95%CI:2.024,8.182);全麻组POD发生率高于椎管内麻醉组,OR值为3.988(95%CI:1.848,8.608);POD组和无POD组术后并发症发生率分别为66.7%和42.0%。结论高龄、术前并存病多、受伤至手术时间长、全麻是老年髋部骨折发生POD的危险因素。     

老年嗜铬细胞瘤手术患者不同麻醉方式与术后转归的关系

目的分析不同麻醉方式对老年嗜铬细胞瘤手术患者术后转归的影响。方法本研究回顾性收集2004年1月至2015年2月入住北京大学第一医院,年龄≥65岁,并行手术治疗的嗜铬细胞瘤患者。收集围术期相关指标包括:人口学资料,原发疾病,手术麻醉情况,术后化验检查,术后并发症及预后指标等。结果本研究纳入33例老年嗜铬细胞瘤患者。按照麻醉方式分为全麻组(G组,n=24)和全麻复合硬膜外组(GE组,n=11)。GE组术中应用瑞芬太尼(18.2%vs 79.2%,P=0.001)或舒芬太尼术中静脉维持镇痛(45.5%vs 79.2%,P=0.046)的比例明显低于G组。GE组术后机械通气时间(P=0.039)、术后住院时间(P=0.013)及住院总时间(P=0.015)均明显短于G组。Cox风险比例模型分析显示,全麻复合硬膜外麻醉为减少术后住院时间的独立保护因素(RR=0.245,95%CI 0.106~0.564,P=0.001),而术中升压药物联合应用为术后住院时间延长的独立危险因素(RR=4.184,95%CI 1.146~15.281,P=0.030)。结论老年嗜铬细胞瘤手术患者术中应用全麻复合硬膜外麻醉较单纯全身麻醉的静脉维持镇痛药物应用更少,机械通气时间更短,并明显缩短了术后住院时间及总住院时间。     

影响膝关节表面置换术后感染的相关因素分析

目的探究影响膝关节表面置换术后感染的相关因素。方法回顾性分析2011年1月至2014年7月于我院行膝关节表面置换术的患者320例,根据患者膝关节表面置换术后是否感染分为感染组(n=13)和非感染组(n=307),运用统计学方法比较两组患者的一般资料、并发症、手术情况等。结果通过单因素分析,发现美国麻醉师协会(America Society of Anesthesiologists,ASA)分级高、合并糖尿病、合并类风湿性关节炎、手术时间长、手术出血量多、有激素治疗史对术后感染的影响有统计学意义(P<0.05);通过多因素分析,发现合并糖尿病[比值比(OR)=4.384,95%可信区间(CI):1.668~9.522]、合并类风湿性关节炎(OR=6.203,95%CI:2.256~13.054)、手术时间(OR=2.396,95%CI:1.336~4.298)、手术出血量(OR=1.756,95%CI:1.177~2.619)、有激素治疗史(OR=4.536,95%CI:2.399~8.576)是膝关节表面置换术患者术后感染的危险因素。结论术前掌握患者的合并症和既往病史、激素治疗史,术中选择合适的手术方式,减少手术时间和出血量,术后加强监测患者病情,有利于降低患者术后的感染率。     

围术期患者因素和麻醉方式对再次剖宫产术中出血风险的影响

目的通过回顾性病例数据分析,探讨围术期患者因素和麻醉方式对再次剖宫产术中出血风险的影响。方法通过检索医院电子病历系统,搜集我院2015年10月至2017年10月再次剖宫产产妇2 442例的临床病历资料,年龄20～45岁,BMI 18～40 kg/m~2,ASAⅠ—Ⅳ级。剖宫产常规采用椎管内麻醉,全麻仅用于患者强烈要求、椎管内麻醉禁忌或失败等情况。根据术中出血标准分为明显出血组(MH组,n=494)和非明显出血组(NMH组,n=1948)。记录产妇的术前、术中和术后的资料。应用Logistic回归分析筛选术中出血的危险因素。采用倾向性匹配分析比较全麻组(GA组,n=141)与非全麻组(NGA组,n=141)术中明显出血发生率、新生儿窒息和住院时间。结果 MH组的术中出血量明显大于NMH组(P0.05)。Logistic回归结果显示再次剖宫产术中出血的危险因素包括:前置胎盘(OR=38.269,95%CI 15.970～91.706,P0.001),宫缩乏力(OR=10.047,95%CI6.155～16.399,P0.001),胎盘粘连(OR=5.045,95%CI 3.146～8.089,P0.001),全麻(OR=2.922,95%CI 1.521～5.614,参考组:非全麻,P0.001)等。倾向性匹配结果显示,GA组术中明显出血发生率明显高于NGA组(P0.05), 1 min新生儿窒息率明显明显高于NGA组(P0.05),住院时间明显长于NGA组(P0.05)。结论再次剖宫产术中出血的风险因素包括前置胎盘、宫缩乏力、胎盘粘连、全麻等。全麻与非全麻比较,可增加术中出血风险和新生儿窒息发生率,延长住院时间。     

胸外科手术患者PACU滞留时间延长的多因素分析

目的分析胸外科手术后患者麻醉后监护室(PACU)滞留时间延长(120min)的影响因素。方法回顾性分析495例胸外科手术患者的麻醉复苏记录单,按Logistic回归分析的要求进行量化或赋值,先行单因素回归,筛选有显著差异的各个因素再做多因素非条件回归分析。结果单因素回归分析:年龄60岁(OR=2.411,95%CI 1.592~3.742),ASA分级每增加1级(OR=1.833,95%CI 1.209~2.780),尿量20ml/h(OR=0.173,95%CI 0.065~0.458),术中心血管活性药物使用(OR=1.613,95%CI 1.198~2.173)对患者PACU滞留时间有明显影响。多因素回归分析:年龄60岁(OR=2.322,95%CI 1.448~3.722),术中心血管活性药物使用(OR=1.441,95%CI 1.050~1.976),尿量≤20ml/h(OR=0.139,95%CI 0.049~0.396)为PACU滞留时间延长的独立危险因素。结论胸外科手术患者PACU滞留时间延长的相关因素有年龄60岁、尿量≤20ml/h、术中使用血管活性药物、ASA分级增加。     

老年髋部骨折术后肺部并发症的危险因素分析

目的探讨引起老年髋部骨折患者术后肺部并发症(PPC)的危险因素。方法回顾性分析广东省江门市五邑中医院骨伤科二区在2012年6月至2015年6月收治的符合纳入标准的老年髋部骨折患者418例,其中男性182例(43.5%),女性236例(56.5%),年龄75~99岁,平均(82±6)岁,根据是否出现PPC进行分组,记录并比较两组患者的年龄、性别、手术方式、麻醉方式、术前并存病、待术时间、血气分析和肺通气功能情况,采用多因素logistic回归分析老年髋部骨折术后并发症的相关危险因素。结果单因素分析示组间年龄x^2=12.473,P=0.001)、麻醉方式x^2=36.721,P<0.001)、术前并存病x^2=16.724,P<0.001)、待术时间(t=4.872,P=0.041)、血气分析x^2=26.341,P<0.001)、肺通气功能x^2=35.431,P<0.001)差异有统计学意义。多因素Logistic回归分析示年龄>85岁组PPC发生率高于年龄<85岁组,OR值为3.673(95%CI:1.684,7.615);待术3~4 d组和5~7 d组和PPC发生率高于1~2 d组(OR:13.349,95%CI:5.391~23.819;OR:16.579,95%CI:6.324~37.324);术前并存病≥3组PPC的发生率高于≤2组(OR:4.069,95%CI:2.024~8.182);全麻组PPC发生率高于椎管内麻醉组(OR:3.579,95%CI:1.848~8.608);血气分析异常组PPC发生率高于血气分析正常组(OR:9.842,95%CI:2.338~7.421);肺通气功能异常组PPC发生率高于肺通气功能正常组(OR:11.384,95%CI:3.652~9.352)。结论高龄、术前并存病≥3种、待术时间长、全身麻醉以及血气分析异常和肺通气功能异常是老年髋部骨折患者发生PPC的危险因素。     

食管癌患者术后肺部感染的围术期影响因素分析

目的探讨围术期相关因素对食管癌患者术后肺部感染的影响。方法回顾性分析2012年8月至2016年8月于我院行食管癌根治术患者的临床资料,150例符合入选标准,根据术后是否并发肺部感染分为肺部感染组(n=32)与非感染组(n=118)。记录两组麻醉药物使用总量,记录两组插管时间、单肺通气时间、手术时间、全麻时间、拔管时间、术中出血量、晶体补充量、胶体补充量、术中总补液量、麻醉方法和单肺通气方式,比较两组非间断膨肺比例、鼻导管吸痰比例和术后哌替啶镇痛比例。通过Logistic回归分析预测肺部感染发生的危险因素。结果肺部感染组舒芬太尼与丙泊酚用量明显多于,单肺通气时间、手术时间、全麻时间、拔管时间明显长于,非间断膨肺比例、鼻导管吸痰比例和术后哌替啶镇痛比例明显高于非感染组(P0.05);两组咪达唑仑与顺阿曲库铵用量、插管时间、术中出血量、晶体补充量、胶体补充量、术中总补液量、麻醉方法及单肺通气方式差异均无统计学意义。Logistic回归分析显示,舒芬太尼用量每增加7.5μg(OR=1.65,95%CI 1.24~2.85)、单肺通气时间每增加10 min(OR=2.14,95%CI 1.32~3.62)、全麻时间每增加20 min(OR=1.87,95%CI 1.46~3.15)、鼻导管吸痰(OR=2.03,95%CI 1.27~3.46)及术后哌替啶镇痛(OR=3.44,95%CI 2.25~5.13)是预测术后肺部感染发生的危险因素。结论麻醉中使用合适的舒芬太尼总量、减少单肺通气时间与全麻时间、应用纤维支气管镜吸痰及术后采取自控静脉镇痛,有利于减少食管癌患者术后肺部感染的发生。     

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.     

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.     

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.