胃癌合并肝硬化术后并发症分析

目的 探讨合并肝硬化的胃癌根治术后并发症的发生情况及其影响因素.方法 回顾性分析1474例胃癌根治术患者的术后并发症发生情况,对41例合并肝硬化患者术后并发症影响因素进行Logistic回归分析.结果 肝硬化组和非肝硬化组患者术后并发症的发生率分别为51.22%和23.94%(x2=15.955,P＜0.01),术后两组的病死率分别为7.32%和0.91%(P=0.009).肝硬化组术后并发症依次为腹水5例,肝功能衰竭4例,切口感染、裂开4例,腹腔感染4例等,主要死亡原因分别为出血、空肠瘘和肝功能衰竭.肝硬化组术后并发症单因素Logistic回归分析显示:年龄(OR=1.277,95%CI:0.991～1.646)、合并腹水(OR=20.900,95%CI:2.349～185.933)、血浆白蛋白水平(OR=0.160,95%CI:0.041～0.629)、Child分级(OR=9.500,95%CI:1.046～86.261)、门静脉高压症(OR=4.000,95%CI:1.057～15.138)、食管静脉曲张(OR=4.400,95%CI:1.095～17.676)、术中输血(OR=3.714,95%CI:1.021～13.511)和术中失血量(OR=1.442,95%CI:1.023～2.034)与胃癌根治术后并发症的发生有关;多因素分析发现:合并腹水(OR=19.213,95%CI:1.569～231.255)、Child分级(OR=12.661,95%CI:0.721～222.458)、食管静脉曲张(OR=6.008,95%CI:0.857～42.097)和术中失血量(OR=1.574,95%CI:0.938～2.640)为并发症发生的独立危险因素.结论 合并有肝硬化的胃癌患者在根治术后的并发症发生率和病死率明显增高;合并腹水、Child分级、合并食管静脉曲张和术中失血量均与胃癌根治术后并发症的发生有关.     

老年营养风险指数联合中性粒细胞/淋巴细胞比值对术后急性肾损伤的预测价值

目的 探讨老年营养风险指数（GNRI）联合中性粒细胞/淋巴细胞比值（NLR）对老年患者结直肠癌根治术后急性肾损伤（AKI）的预测价值。
方法 选择择期全麻下行结直肠癌根治术老年患者670例,男375例,女295例,年龄≥65岁,BMI 16～35 kg/m²,ASA Ⅰ—Ⅲ级。收集患者临床资料,根据术后7 d内是否发生AKI将患者分为两组：AKI组和非AKI组。采用单因素分析和多因素Logistic回归分析确定老年患者结直肠癌根治术后AKI的独立危险因素。绘制受试者工作特征（ROC）曲线,并通过ROC曲线下面积（AUC）评价术前NLR、术前GNRI及联合检测对老年患者结直肠癌根治术后AKI的预测价值。采用决策曲线分析法（DCA）确定术前NLR、术前GNRI及联合检测时预测老年患者结直肠癌根治术后AKI的临床实用性。
结果 有89例（13.3%）患者发生术后AKI。单因素分析显示：与非AKI组比较,AKI组年龄≥75岁、合并糖尿病、使用血管紧张素转换酶抑制剂/血管紧张素受体阻滞剂、术前NLR、手术时间≥3 h、术中低血压及术中输红细胞比例明显升高（P＜0.05）,BMI≥28 kg/m²比例及术前GNRI明显降低（P＜0.05）。多因素Logistic回归分析显示：合并糖尿病（OR=2.140,95％CI 1.125～4.070,P=0.020）、术前NLR值升高（OR=1.608,95％CI 1.414～1.830,P＜0.001）和术中低血压（OR=2.326,95％CI 1.106～4.892,P=0.026）为老年患者结直肠癌根治术后AKI的独立危险因素,术前GNRI值升高（OR=0.868,95％CI 0.838～0.899,P＜0.001）为保护因素。术前NLR、术前GNRI及联合检测预测老年患者结直肠癌根治术后AKI的AUC分别为0.713（95％CI 0.677～0.747）、0.774（95％CI 0.741～0.805）和0.850（95％CI 0.820～0.876）。DCA曲线分析显示,当阈值为0.10～0.95时,术前GNRI联合术前NLR预测老年患者结直肠癌根治术后AKI的净获益率优于术前NLR或GNRI的单独预测。
结论 术前NLR和术前GNRI可用于预测老年患者结直肠癌根治术后AKI的发生风险,且二者联合预测老年患者结直肠癌根治术后AKI风险的效能和净获益率更高。     

老年患者胃肠道肿瘤术后急性肾损伤的危险因素

目的 分析老年患者胃肠道肿瘤术后急性肾损伤（AKI）的危险因素。
方法 回顾性收集2018年9月至2021年12月行胃肠道肿瘤手术的老年患者343例，男251例，女92例，年龄65～85岁，ASA Ⅰ—Ⅲ级。根据术后是否发生AKI分为两组：AKI组（n=63）和非AKI组（n=280）。查阅电子病历系统收集年龄、心功能分级、高血压、糖尿病、冠心病、低蛋白血症、术前1周贫血程度，手术类型、术前肌酐、肾小球滤过率、尿酸和尿素氮水平、术中和术后转归等情况。单因素分析后将P<0.1的变量纳入二元逻辑回归进行多因素分析，筛选AKI的独立预测因素并建立风险预测模型，通过Medcalr软件绘制受试者工作特征（ROC）曲线。
结果 有63例（18.4%）患者发生术后AKI。单因素分析结果显示，与非AKI组比较，AKI组年龄明显增大，心功能分级明显升高，术前高血压、糖尿病、冠心病、低蛋白血症、轻中度贫血比例明显升高（P<0.1）。多因素Logistic回归分析显示，术前高血压（OR=2.119，95%CI 1.181～3.800，P=0.012）、冠心病（OR=2.931，95%CI 1.024～8.386，P=0.045）、低蛋白血症（OR=2.640，95%CI 1.107～6.295，P=0.029）、轻度贫血（OR=3.890，95%CI 1.922～7.875，P<0.001）、中度贫血（OR=3.089，95%CI 1.437～6.637，P=0.004）为术后AKI的独立危险因素，最后根据各独立预测因素建立术后AKI的风险预测模型ROC曲线下面积为0.740（95%CI 0.690～0.785，P<0.001），敏感性为79.4%，特异性为56.1%。
结论 术前存在高血压、冠心病、低蛋白血症、轻中度贫血为胃肠道肿瘤手术老年患者术后AKI的独立危险因素。     

老年患者术前衰弱与术后并发症的相关性

目的 分析非心脏手术老年患者术后并发症的危险因素。方法 回顾性分析2021年3—8月行择期非心脏手术老年患者224例,男122例,女102例,年龄≥65岁,ASAⅠ—Ⅳ级。采用临床衰弱量表(CFS)评估患者术前衰弱状态。根据术后30 d是否发生并发症将患者分为两组：并发症组和非并发症组。采用单因素和多因素Logistic回归分析影响老年患者非心脏手术后并发症的危险因素。结果 共有64例(28.6%)患者发生术后并发症。与非并发症组比较,并发症组年龄、查尔森共病指数(CCI)明显增大,ASA分级明显增高,合并高血压、冠心病比例、衰弱比例、中性粒细胞浓度明显升高,白蛋白、Hb、淋巴细胞浓度明显降低,出血量明显增多,手术时间和麻醉时间明显延长(P<0.05)。多因素Logistic回归分析结果显示,年龄增大(每增大1岁,OR=1.142,95%CI 1.064～1.225,P<0.05)和术前衰弱(OR=12.028,95%CI 3.727～38.816,P<0.05)是术后并发症的独立危险因素。结论 年龄增大和术前衰弱是老年患者非心脏手术后并发症的独立危险因素。     

合并巨大左心室的心脏瓣膜病患者术后发生急性肾损伤的危险因素分析

目的 探讨合并巨大左心室的心脏瓣膜病患者心脏瓣膜术后发生急性肾损伤(AKI)的危险因素。方法 回顾性分析2018-01—2020-12在阜外华中心血管病医院行心脏瓣膜手术且合并巨大左心室的心脏瓣膜病患者的临床资料，根据术后是否发生AKI,分为AKI组和非AKI组。比较2组患者的基线、术中和术后资料。将单因素分析中P<0.2的变量放入多因素Logistic回归方程中，分析AKI与各因素的相关性。随后将连续型变量放入构建的回归模型中进行趋势性检验，进一步分析连续型变量对AKI的影响。结果 研究共纳入132例合并巨大左心室的心脏瓣膜病患者，年龄(52.9±12.5)岁；28例于术后发生AKI,非AKI组104例。单因素分析结果显示，合并糖尿病、合并脑血管疾病、围术期输血、主动脉阻断时间、体外循环时间等项目的差异有统计学意义(P<0.05)。多因素Logistic回归分析显示，基础血肌酐升高(OR=3.311,95%CI 1.086～10.096,P=0.035)、主动脉阻断时间(OR=1.022,95%CI 1.008～1.037,P=0.003)、围术期输血(OR=2.850,...     

ASA Ⅰ或Ⅱ级患者全膝关节置换术后急性肾损伤的危险因素

目的 探讨ASA Ⅰ或Ⅱ级患者全膝关节置换术后急性肾损伤（AKI）的危险因素。
方法 回顾性分析2014年1月至2019年12月初次行全膝关节置换术的患者2 623例，男513例，女2 110例，年龄≥18岁，ASA Ⅰ或Ⅱ级。收集人口学信息、围术期资料和术后AKI的发生情况。按照改善全球肾脏病预后组织标准（KDIGO），根据术后48 h内是否发生AKI将患者分为两组：AKI组和非AKI组。采用二元Logistic回归分析ASA Ⅰ或Ⅱ级患者全膝关节置换术后AKI的独立危险因素。
结果 有51例（1.9%）患者发生术后AKI。二元Logistic回归分析显示，围术期输血（OR=3.979，95%CI 2.243～7.056，P<0.001）、手术时间延长（OR=1.007，95%CI 1.001～1.013，P=0.031）和围术期复合应用抗生素（万古霉素+头孢呋辛/克林霉素）（OR=4.053，95%CI 1.350～12.165，P=0.013）是术后急性肾损伤的独立危险因素。
结论 围术期输血、手术时间延长和复合应用抗生素（万古霉素+头孢呋辛/克林霉素）是ASA Ⅰ或Ⅱ级患者全膝关节置换术后AKI的危险因素。     

心肺转流下心脏瓣膜术后急性肾损伤的危险因素分析

目的探讨成人心肺转流(cardiopulmonary bypass,CPB)下心脏瓣膜手术后急性肾损伤(acute kidney injury,AKI)的危险因素。方法回顾性分析1 349例心脏瓣膜手术患者的临床资料,采用多因素Logistic回归分析心脏瓣膜术后AKI的危险因素。结果 1 349例心脏瓣膜手术患者AKI发生率为28.4%,多因素Logistic回归分析显示,每增加1岁(OR=1.05,95%CI 1.03~1.06,P0.001)、糖尿病史(OR=2.11,95%CI 1.22~3.68,P=0.008)、贫血(OR=1.50,95%CI1.05~2.21,P=0.026)、术前血清肌酐(Scr)值每增加1mg/dl(OR=1.01,95%CI 1.01~1.02,P=0.001)、手术时间每增加1h(OR=1.28,95%CI 1.15~1.41,P0.001)、术中输注血浆(OR=1.50,95%CI 1.14~1.97,P=0.004)是心脏瓣膜术后发生AKI的独立危险因素。结论心肺转流下心脏瓣膜术后急性肾损伤的独立危险因素是高龄、糖尿病史、贫血、术前肌酐高、手术时间长以及术中输注血浆。     

结直肠癌患者术后急性肾损伤的相关因素分析

目的分析影响结直肠癌患者术后发生急性肾功能损伤(AKI)的相关因素。方法回顾性分析2018年1月至2021年6月在郑州大学附属肿瘤医院接受结直肠癌手术376例患者的临床资料, 根据改善全球肾脏病预后组织AKI诊断标准将患者分为AKI组(n=29)和非AKI组(n=347), 比较两组患者的人口学信息、围手术期状况、实验室检查结果, 采用多因素Logistic分析结直肠癌患者术后发生AKI的独立危险因素。结果 376例患者中有29例(7.7%)患者术后发生AKI。多因素分析显示:术前合并高血压(OR=3.487, 95%CI:1.081～11.251, P=0.037)、术前贫血(OR=3.158, 95%CI:1.114～8.953, P=0.031)、术中输注晶体量不足(OR=0.998, 95%CI:0.997～0.999, P=0.007)、术中最低平均动脉压值较低(OR=0.915, 95%CI:0.863～0.970, P=0.003)及术后Hb中～重度下降(OR=4.105, 95%CI:1.487～11.335, P=0.006)是结直肠癌患者术后发生AKI的独立危险因素...     

左心功能中重度不全患儿行左冠状动脉异常起源矫治术后发生急性肾损伤的危险因素分析

目的回顾性分析左冠状动脉异常起源于肺动脉(anomalous origin of the left coronary artery from the pulmonary artery,ALCAPA)伴左心功能中重度不全的患儿行矫治术后发生急性肾损伤(acute kidney injury,AKI)的危险因素。方法选择2010年11月至2017年5月行ALCAPA矫治术伴术前左室射血分数(left ventricular ejection fraction,LVEF)低于50%的患儿43例,男25例,女18例,年龄3个月至14岁。查阅医院电子病例,收集相关围术期临床资料。根据KIDGO标准判断是否发生AKI,将患儿分为两组:非AKI组和AKI组。采用多因素Logistic回归分析术后AKI的危险因素。结果术后发生AKI 31例,AKI发生率为70.5%。AKI组术前Hb含量、术前LVEF和术前血浆肌酐(SCr)浓度明显低于非AKI组(P0.05)。多因素Logistic回归分析显示,术前Hb含量升高为保护性因素(OR=0.917,95%CI 0.848～0.992,P=0.031);术前LVEF升高为保护性因素(OR=0.902,95%CI 0.819～0.993,P=0.036);术前肾小球滤过率(GFR)升高为独立危险因素(OR=1.063,95%CI 1.014～1.113,P=0.011)。结论 ALCAPA伴左心功能中重度不全的患儿行矫治术,术前Hb含量升高和LVEF升高均是术后发生AKI的保护性因素,而术前GFR升高是术后AKI的独立危险因素。     

胰十二指肠切除术后急性肾损伤的危险因素分析

目的探讨开腹胰十二指肠切除术后急性肾损伤(acute kidney injury, AKI)的危险因素。方法回顾性分析2011年11月—2018年4月行开腹胰十二指肠切除术患者389例,男219例,女170例,年龄25～79岁,ASAⅠ—Ⅳ级。收集相关围术期资料,统计术后AKI、性别、BMI、合并梗阻性黄疸、服用血管紧张素转换酶抑制剂(ACEI)或血管紧张素Ⅱ受体阻滞剂(ARB)类降压药和术后Hb等情况。采用多因素Logistic回归分析术后AKI的独立危险因素。结果术后AKI有46例(11.8%)。多因素Logistic回归分析显示,男性(OR=2.33,95%CI 1.13～4.82,P=0.023)、BMI≥24 kg/m~2(OR=2.39,95%CI 1.23～4.65,P=0.010)、合并梗阻性黄疸(OR=3.29,95%CI 1.70～6.37,P0.001)、服用ACEI或ARB(OR=3.93,95%CI 1.08～14.38,P=0.038)和术后Hb中重度下降(OR=3.81,95%CI 1.13～12.89,P=0.031)是开腹胰十二指肠切除术后AKI的独立危险因素。结论男性、BMI≥24 kg/m~2、合并梗阻性黄疸、服用ACEI或ARB、术后Hb中重度下降是开腹胰十二指肠切除术后AKI的独立危险因素。     

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.