循环肿瘤细胞对肝癌射频消融术后复发的预测价值

目的研究分析射频消融术(RFA)前循环肿瘤细胞(CTC)预测肝癌术后复发的应用价值。方法收集2016年6月至2019年9月中山市人民医院收治的168例肝细胞癌患者,在RFA治疗前以Cyttel检测法分析患者外周血的CTC。利用X-tile软件的Kaplan-Meier模块确定CTC的最佳临界值,并分析CTC与术前临床参数的关系,Cox比例风险模型分析影响RFA术后复发的独立危险因素,采用Kaplan-Meier法绘制RFA术后复发曲线图明确CTC与RFA术后复发的关系。结果预测肝癌RFA术后复发的CTC最佳临界值为2个/3.2 ml。术前CTC与肿瘤结节数目、最大肿瘤直径、术前AFP水平以及中国肝癌临床分期(CNLC)有关(P<0.05)。术前CTC(HR=1.965,95%CI:1.314~2.937,P=0.001)、AFP水平(HR=1.743,95%CI:1.158~2.623,P=0.008)、PIVKA-Ⅱ(HR=1.559,95%CI:1.008~2.411,P=0.046)以及最大肿瘤直径(HR=1.994,95%CI:1.104~3.602,P=0.022)均是肝癌RFA术后复发的独立危险因素。术后复发率62.5%(105/168),CTC≤2个/3.2 ml患者的累积复发率明显低于CTC>2个/3.2 ml者(P<0.001)。结论术前CTC检测对预测肝癌射频消融术后复发有一定的应用价值及临床意义。     

术前中性粒细胞与淋巴细胞比值和血小板与淋巴细胞比值对肾透明细胞癌的预后评估价值

目的:探究术前外周血中性粒细胞与淋巴细胞比值(NLR)和血小板与淋巴细胞比值(PLR)在评估肾透明细胞癌(ccRCC)患者预后的作用。方法:回顾性分析2001年12月—2010年12月在我院接受手术治疗的352例肾细胞癌(RCC)患者的临床资料,年龄25~82岁,平均(55.1±12.2)岁;随访时间1~200个月,平均(106.1±35.1)个月;中位总生存期(OS)为104个月,中位无复发生存期(RFS)为101个月。通过受试者工作特征曲线(ROC)确定NLR及PLR的最佳临界值并进行分组,通过Kaplan-Meier法和Cox回归对RCC患者中的NLR及PLR进行预后分析。结果:按最佳临界值NLR<2.05(155例)及≥2.05(197例)、PLR<140(236例)及PLR≥140(116例)对患者进行分组。高NLR及PLR与大肿瘤直径(P=0.026,P=0.019)、高肿瘤TNM分期(P=0.003,P<0.001)、高肿瘤Fuhrman分级(P=0.021,P=0.008)及转移或复发有关(P<0.001,P<0.001)。相比于单独使用NLR或PLR,联合NLR及PLR能够更有效地预测OS及RFS。Cox多因素分析结果提示高NLR(P<0.001)、高PLR(P=0.004)、患者年龄≥60岁(P<0.001)、大肿瘤直径(P=0.043)、高肿瘤TNM分期(P<0.001)、高肿瘤Fuhrman分级(P<0.001)与患者OS相关,并且高NLR(P=0.012)、高PLR(P=0.014)、高肿瘤TNM分期(P<0.001)、高肿瘤Fuhrman分级(P=0.002)与患者RFS相关。结论:术前NLR及PLR是ccRCC患者术后OS及RFS的独立预后因素。高NLR、PLR预示着ccRCC患者较高的复发转移风险及较差的生存预后。     

术前外周血NLR、PLR在经尿道非肌层浸润性膀胱肿瘤切除术预后中的意义

目的:探讨非肌层浸润性膀胱癌(NMIBC)患者经尿道膀胱肿瘤切除术(TURBT)前外周血参数中性粒细胞与淋巴细胞比值(NLR)及血小板与淋巴细胞比值(PLR)在预后中的意义。方法:回顾性分析156例NMIBC患者的一般资料并按照术后随访结果分为复发组(92例)和无进展组(64例);根据术前血常规指标计算出NLR和PLR,进行ROC曲线分析获取复发组和无进展组之间的最佳界限值,再将患者分别分为高NLR和低NLR、高PLR和低PLR两类。将NLR、PLR合并一般资料进行Kaplan-Meier单因素无进展生存分析,Log-rank检验差异,再将接近有意义的指标(P0.1)纳入多因素Cox回归,分析预后的独立危险因素。分析NLR和PLR的相关性及联合使用对预后的意义。结果:ROC曲线分析显示NLR、PLR在复发组和无进展组间最佳界限值分别为2.75和166;单因素Kaplan-Meier分析显示合并慢性肾病、TNM分期、癌灶数量、合并肾积水及NLR、PLR是复发的影响因素,其中高NLR组中位无进展生存期低于低NLR组(40个月vs.48个月,P0.05),高PLR组低于低PLR组(38个月vs.48个月,P0.05);Cox多因素回归分析显示高NLR[OR(95%CI)=2.307(1.347~3.950),P=0.002]和合并有慢性肾病、多发肿瘤、TNM分期、合并肾积水是术后复发的独立危险因素。NLR和PLR之间具有正相关性(r=0.160,P=0.046),且二者的联合变量对应无复发生存期差异有统计学意义,可用于预后。结论:术前外周血参数NLR和PLR对NMIBC患者TURBT术后的预后有一定提示意义,高NLR和高PLR相对低NLR和低PLR有更高的复发风险。     

术前血清ALT水平与胃癌患者预后的相关性研究

目的探讨胃癌患者术前血清ALT水平与预后的相关性。方法回顾性分析2008年1月至2010年12月期间在哈尔滨医科大学附属肿瘤医院胃肠外科行胃癌手术治疗的491例胃癌患者的临床资料。以血清ALT最佳ROC曲线截点为参考对患者进行分组,分析血清ALT与患者临床因素之间的关系,并进行单因素和多因素生存分析。结果血清ALT矣20.05U/L组患者有201例,血清ALT>20.05U/L组患者有290例。血清ALT与患者的年龄(X^2=11.231,P<0.001)、肿瘤浸润深度(X^2=23.178,P<0.001)、血清GGT(X^2=19.190,P<0.001)及血清AST(X^2=30.771,P<0.001)均有关。血清ALT:S20.05 U/L组和血清ALT>20.051;几组患者的1、3、5年生存率分别为83.5%、51.4%、42.1%和66.2%、27.4%、15.7%,两组比较差异均有统计学意义(X^2=41.711,P<0.001)。多因素分析显示,肿瘤TNM分期(HR=1.882,95%CI:1.468-2.413,P<0.001)、肿瘤浸润深度(HR=1.161,95%CI:1.020-1.322,P=0.024)、淋巴结转移(HR=1.177,95%CI:l.042-1.329,P=0.009)、Hb(HR=0.726,95%CI:0.579-0.909,P=0.005)、中性粒细胞/淋巴细胞比值(HR=1.275,95%CI:1.002-1.623,P=0.048)及血清ALT(HR=2.191,95%CI:1.754~2.738,P<0.001)均为影响胃癌患者预后的独立危险因素。结论血清ALT是胃癌患者预后的独立危险因素。     

术前外周血NLR和PLR与原发性胃癌病程进展的关系

目的:探讨外周血中性粒细胞与淋巴细胞比值(NLR)、血小板与淋巴细胞比值(PLR)与原发性胃癌病程进展的关系。方法:回顾性分析2015年2月—2016年2月收治的188例原发性胃癌患者的临床资料,分析肿瘤不同浸润深度、淋巴结分期及TNM分期组间患者NLR值和PLR值的差异及相关性。结果:原发性胃癌不同浸润深度、淋巴结分期及TNM分期患者NLR值和PLR值差异均有统计学意义(P0.001);高NLR组、PLR组胃癌患者肿瘤浸润深度、淋巴结分期和TNM分期均较低NLR组、PLR组高,差异有统计学意义(P0.001);NLR与PLR呈明显正性相关(r=0.379,P0.001);多重线性回归进一步分析显示上述因素对术前NLR、PLR有显著影响(P0.05)。结论:术前外周血NLR和PLR升高对胃癌进展具有一定的预测价值,NLR值和PLR值越高提示胃癌病程越晚,预后越差。     

术前血清丙氨酸氨基转移酶与天冬氨酸氨基转移酶比值对胃癌患者预后的影响

目的研究胃癌患者肝功能指标丙氨酸氨基转移酶和天冬氨酸氨基转移酶比值(LSR)与临床病理因素的关系及其对预测患者生存期的临床意义。方法采用回顾性病例对照研究的方法。回顾性分析2007年1月至2010年12月期间在哈尔滨医科大学附属肿瘤医院胃肠外科行胃癌手术治疗、且术后病理及随访资料完整的891例进展期胃癌患者的临床资料。病例纳入标准:(1)术前明确诊断为胃癌,排除残胃癌及胃其他肿瘤;(2)术前未行新辅助治疗;(3)不合并其他严重疾病如急性冠心病、肝硬化、慢性肾衰等;(4)行胃癌根治术,排除姑息治疗或开腹探查病例;(5)术后病理资料完全,随访信息完整;(6)死亡原因与胃癌相关。取患者入院时采血结果,利用受试者工作特征曲线(ROC)分别对LSR、血红蛋白、淋巴结转移率、肿瘤最大直径、碱性磷酸酶、谷氨酰转肽酶、总胆红素和乳酸脱氢酶取最佳截点。根据LSR截点分组,分析LSR与临床病理因素之间的关系,对不同LSR组别进行总体生存率的比较。并将相关临床因素和LSR纳入单因素和多因素Cox生存分析。结果LSR的ROC曲线最佳截点为1.43,LSR<1.43组682例,LSR≥1.43例209例。血红蛋白、淋巴结转移率、肿瘤长径、碱性磷酸酶、谷氨酰转肽酶、总胆红素和乳酸脱氢酶的ROC曲线最佳截点分别为130.2 g/L、18.0%、4.75 cm、68.1 U/L、16.55 U/L、5.58μmol/L和135.8 U/L。LSR<1.43组与LSR≥1.43组患者比较,年龄(χ^2=4.412,P=0.036)、肿瘤浸润深度(χ^2=64.306,P<0.001)、组织学类型(χ^2=8.026,P=0.005)、碱性磷酸酶(χ^2=8.217,P=0.004)、谷氨酰转肽酶(χ^2=33.207,P<0.001)、总胆红素(χ^2=14.012,P<0.001)和乳酸脱氢酶(χ^2=63.630,P<0.001)的差异均有统计学意义。LSR<1.43组和LSR≥1.43组1、3、5年生存率分别为70.8%、31.3%、25.0%和64.9%、24.4%、11.3%,两组比较差异有统计学意义(χ^2=10.140,P=0.001)。单因素分析显示,年龄、血红蛋白水平、肿瘤TNM分期、肿瘤浸润深度、淋巴结转移率、淋巴结转移、组织学类型、肿瘤长径、谷氨酰转肽酶、总胆红素和LSR是影响胃癌患者预后的相关因素(均P<0.05);多因素分析显示,肿瘤TNM分期(HR=1.605,95%CI:1.332~1.936,P<0.001)、肿瘤浸润深度(HR=1.299,95%CI:1.168~1.445,P<0.001)、淋巴结转移率(HR=2.400,95%CI:1.873~3.076,P<0.001)、淋巴结转移(HR=1.263,95%CI:1.106~1.478,P=0.007)、肿瘤长径(HR=1.375,95%CI:1.134~1.669,P=0.001)和LSR(HR=1.427,95%CI:1.190~1.711,P<0.001)是影响胃癌患者预后的独立危险因素。结论LSR是胃癌患者预后的独立危险因素,且检测简单易行,是胃癌预后的潜在标志物。因此,在术前综合治理阶段,应尽可能恢复和提高肝功能状态有助于改善胃癌患者预后,延长患者生存时间。     

胰腺体尾部导管腺癌生存预后的影响因素分析

目的 探讨影响胰体尾癌患者生存预后的临床病理因素。方法 回顾性收集2010年1月～2021年11月112例胰体尾癌根治术的胰腺导管腺癌患者的临床病理资料，采用Cox比例风险回归模型进行单因素及多因素分析筛选与生存预后相关的临床病理特征。结果 112例中，术后病理可见脉管浸润36例，神经浸润94例。术后中位生存时间19个月，1年、3年、5年生存率分别为67.3%、27.4%、14.7%。单因素分析显示，更高的pT分期、TNM分期、淋巴结转移及脉管浸润等病理特征，以及术前CA19-9水平、术后1个月CA19-9水平、手术方式、术中出血量、联合血管切除以及术后辅助化疗等临床特征，与胰体尾癌患者的生存预后相关(P<0.05)。多因素分析结果显示，脉管浸润(HR=1.938,95%CI:1.173～3.201,P=0.010),更高的TNM分期(HR=2.133,95%CI:1.045～4.353,P=0.037),术后CA19-9高(HR=2.349,95%CI:1.431～3.855,P=0.001),联合血管切除(HR=2.352,95%CI:1.229～4.504,P=0.010)...     

非休克型肝癌自发性破裂出血术后TAE的价值

目的:探讨非休克型肝癌自发性破裂出血术后接受肝动脉栓塞术(TAE)治疗的远期效果。方法:收集162例非休克型肝癌自发性破裂出血并接受手术治疗患者的临床病理资料和随访资料,对影响预后的相关因素行单因素和多因素分析,并根据术后是否接受TAE治疗分为两组,用Kaplan-Meier法比较两组生存差异。结果:单因素分析表明,对于非休克型肝癌自发性破裂出血的患者,肿瘤直径(P=0.008)、肝硬化(P=0.03)、肿瘤位置(P=0.028)以及治疗方法(P=0.012)与预后有关。多因素分析提示,肿瘤直径(HR=1.954,95%CI=1.691~5.526,P=0.007),肝硬化(HR=1.544,95%CI=1.003~2.000,P=0.041),肿瘤位置(HR=1.785,95%CI=1.023~3.114,P=0.026),治疗方法(HR=1.692,95%CI=1.131~2.533,P=0.011)是影响非休克型肝癌自发性破裂出血患者预后的独立危险因素。生存分析表明术后接受TAE治疗者预后较单纯手术者好(P<0.001)。结论:术后接受TAE治疗可改善非休克型肝癌自发性破裂出血患者的预后。     

甲状腺髓样癌患者术后生存及预后因素分析

目的:探讨影响甲状腺髓样癌(MTC)患者的术后生存情况与预后的影响因素。方法:回顾性分析中国医科大学附属盛京医院2001年1月—2017年12月收治的78例MTC患者资料,根据随访结果计算患者的术后生存率,采用单因素及多因素回归分析确定预后的影响因素。结果:78例患者中,74例患者获得随访3～189个月,10例死于疾病,其余患者均存活,其1、3、5、10、15年生存率分别为98.6%、93.5%、88.4%、73.2%、73.2%;单因素分析显示性别(χ~2=6.873,P=0.009)、颈部淋巴结转移(χ~2=4.047,P=0.048)、远处转移(χ~2=23.530,P0.001)、肿瘤临床分期(cTNM分期)(χ~2=16.067,P0.001)影响患者预后;而多因素分析表明仅远处转移(HR=54.956,95%CI=6.341～476.257,P0.001)及肿瘤cTNM分期(HR=2.214,95%CI=1.061～4.619,P=0.034)是影响MTC患者生存的独立影响因素。结论:远处转移与高cTNM分期是MTC不良预后的重要因素,早期诊断及治疗有助于患者长期生存。     

术前淋巴细胞/单核细胞比值与可切除性胰腺癌预后的相关性分析

目的探讨术前淋巴细胞/单核细胞比值(lymphocyte-to-monocyte ratio,LMR)与可切除性胰腺癌患者预后的相关性。方法回顾性分析2008年1月~2013年11月我院149例胰腺腺癌行胰腺癌根治术的临床资料,采用最大选择检验法确定术前LMR对于总生存时间的最佳临界值。采用Cox比例风险回归模型分析影响患者生存预后的因素。采用KaplanMeier生存曲线分析LMR对不同AJCC分期患者总生存时间的影响。结果术前LMR的最佳临界值为3.4,将患者分为高LMR组(LMR≥3.4,62例)和低LMR组(LMR3.4,87例)。单因素分析显示,患者总生存时间与癌胚抗原、糖类抗原125、糖类抗原19-9、手术切缘、AJCC分期、淋巴结转移、淋巴细胞数、单核细胞数及术前外周血LMR有关;多因素分析显示,癌胚抗原≥5μg/L(HR=1.723,95%CI:1.122~2.645,P=0.013),手术切缘阳性(HR=2.168,95%CI:1.356~3.466,P=0.001)和淋巴结转移阳性(HR=1.699,95%CI:1.153~2.502,P=0.007)是患者总生存时间的独立危险因素,术前LMR≥3.4是患者预后的保护因素(HR=0.442,95%CI:0.295~0.660,P=0.000)。高LMR组和低LMR组患者中位总生存时间分别为17.9月和8个月,差异有统计学意义(log-rank χ~2=27.672,P=0.000)。结论术前LMR与可切除性胰腺腺癌患者的预后具有相关性,术前高LMR患者预后较好。     

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.