腹腔镜和开腹直肠癌根治术的安全性及远期疗效比较

目的 探讨腹腔镜和开腹直肠癌根治术的安全性及远期疗效的差异.方法 回顾性分析2000年1月至2008年12月福建医科大学附属协和医院收治的602例行直肠癌根治术患者的临床资料.根据手术方式将患者分为腹腔镜组(324例)和开腹组(278例).比较两组患者淋巴结清扫数目、切除肿瘤标本的近端和远端切缘长度、局部复发率、远处转移率、生存率、无瘤生存率等.计数资料采用独立样本t检验,生存率采用寿命表法计算,采用Wilcoxon( Gehan)检验进行比较,复发率和转移率的比较采用x2检验或Fisher确切概率法.结果 腹腔镜组和开腹组平均淋巴结清扫数目分别为(21±8)枚和(21±9)枚,两组比较,差异无统计学意义(t=1.120,P＞0.05)；腹腔镜组和开腹组近端切缘长度分别为(15.1±1.3)cm和(15.0 ±0.8)cm,两组比较,差异无统计学意义(t=1.452,P＞0.05)；远端切缘长度分别为(4.0±1.6)cm和(3.3±1.4)cm,两组比较,差异有统计学意义(t=5.587,P＜0.05).局部总体复发率为5.6％( 34/602),无切口或戳孔种植.腹腔镜组与开腹组局部复发率分别为6.2％( 20/324)和5.0％ (14/278),两组比较,差异无统计学意义(x2=0.363,P＞0.05).总体远处转移率为11.5％ (69/602),腹腔镜组和开腹组远处转移率分别为11.1％ (36/324)和11.9％(33/278),两组比较,差异无统计学意义(x2 =0.085,P＞0.05).腹腔镜组和开腹组3年生存率分别为87.8％和84.9％,5年生存率分别为83.0％和79.3％,两组比较,差异无统计学意义(P＞0.05).两组3年无瘤生存率分别为79.4％和79.7％,5年无瘤生存率分别为69.2％和73.1％,两组比较,差异无统计学意义(P＞0.05).本组随访率为81.2％(489/602),49例患者死亡,其中腹腔镜组20例,开腹组29例.结论 腹腔镜直肠癌根治术不仅在肿瘤学安全性上是可靠的,而且可以达到和传统开腹手术同样的远期疗效.     

远端进展期胃癌腹腔镜辅助与开腹根治术的远期疗效比较

目的 探讨进展期胃癌腹腔镜根治术的安全性和可行性,并评价其远期临床疗效。方法 对2004年1月至2009年6月远端进展期胃癌行腹腔镜辅助胃癌根治术346例患者的临床及随访资料和同期在我院行传统开腹胃癌手术的313例进行回顾性分析,比较两组的手术安全性、术后并发症、生存率以及癌症复发转移情况。结果 腹腔镜组手术平均用时与开腹组相比差异无统计学意义[(211±56) min比（204±41）min,P＞0.05]。腹腔镜组术中出血量、切口长度显著低于开腹手术组。腹腔镜组肿瘤近、远端切缘长度分别为(6.3±2.0) cm、(5.7±1.7)cm,开腹组分别为(6.3±2.1) cm、(5.6±1.6) cm,两组相比差异均无统计学意义。腹腔镜组淋巴结清扫数量为(33±13)枚,开腹组为(33±16)枚,两组相比差异无统计学意义。腹腔镜组术后并发症的发生率显著低于开腹组（6.7％比13.1％,P＜0.01）。随访时间6～72个月,平均37个月,腹腔镜组1、3、5年生存率分别为87.2％、57.2％和50.3％,开腹组分别为87.1％、54.1％和49.2％,两组相比差异均无统计学意义。两组癌症复发转移率相比差异无统计学意义。结论 腹腔镜辅助的进展期胃癌根治术与开腹组在生存率及术后复发方面无显著差异,且具有创伤小、术后恢复快、并发症少等优点。     

腹腔镜辅助远端胃癌根治术安全性和生存状况分析

目的 评估腹腔镜辅助远端胃癌根治术的安全性和长期生存情况.方法 行远端胃癌根治术患者360例,其中160例行腹腔镜手术(腹腔镜组),200例行开腹手术(开腹组),比较两组患者手术安全性、术后并发症和生存率.结果 腹腔镜组手术出血量和术后住院时间分别为(42.5±15.3)ml和(9.5±2.6)天,均少于开腹组,差异有统计学意义(P＜0.05).两组手术时间、淋巴结清扫数目和术后并发症比较,差异均无统计学意义(P＞0.05).两组患者随访时间6 ～ 60个月,平均32个月,腹腔镜组与开腹组1、3、5年总体生存率分别为95.3％、82.7％、60.3％和95.4％、79.2％、60.3％,两组比较,差异无统计学意义(P＞0.05).结论 腹腔镜辅助远端胃癌根治术安全可行,有创伤小,恢复快,并发症少.腹腔镜组在术后生存率与开腹手术组相当.     

达芬奇机器人手术系统与腹腔镜及开腹胃癌根治术腹腔冲洗液癌胚抗原和多巴脱羧酶的变化

目的 探讨达芬奇机器人手术系统、腹腔镜及开腹胃癌根治术腹腔冲洗液CEA和多巴脱羧酶（DDC）的变化.方法 回顾性分析2013年1月至2014年3月第三军医大学西南医院收治的126例行胃癌根治术患者的临床资料,其中行达芬奇机器人手术系统胃癌根治术、腹腔镜胃癌根治术、开腹胃癌根治术者各42例,设为机器人手术组、腹腔镜手术组和开腹手术组.收集患者手术前后腹腔冲洗液,采用ELISA法检测CEA和DDC浓度.计量资料采用配对t检验及方差分析,多重比较采用LSD法,计数资料采用x2检验及非参数检验.结果 机器人手术组、腹腔镜手术组和开腹手术组患者术前腹腔冲洗液中CEA浓度分别为（242±189） μg/L、（221±174） μg/L和（257±135） iμg/L,术后CEA浓度分别为（1 262 ±785） μg/L、（1 172 ±699） μg/L和（2 996±1 947） μg/L;3组患者术前腹腔冲洗液中DDC浓度分别为（8±5） μg/L、（7±4） μg/L和（8±6） μg/L,术后DDC浓度分别为（87±55） μg/L、（81 ±52） μg/L和（146±135） lμg/L.3组患者术前CEA与DDC浓度比较,差异无统计学意义（F =0.491,0.161,P＞0.05）;3组患者术后CEA与DDC浓度比较,差异有统计学意义（F =27.214,6.865,P＜0.05）.两两比较术后CEA与DDC浓度发现：开腹手术组较腹腔镜及机器人组明显升高（P＜0.05）,而腹腔镜手术组与机器人手术组比较,差异无统计学意义（P＞0.05）.分析同种手术方式手术前后腹腔冲洗液中CEA和DDC浓度：3组术后CEA和DDC浓度均较术前显著增高,差异有统计学意义（t=-11.053、-11.700、-9.780,-10.261、-9.955、-6.969,P＜0.05）.结论 达芬奇机器人手术系统胃癌根治术与腹腔镜胃癌根治术比较,术后腹腔冲洗液中CEA和DDC浓度差异无统计学意义,但均明显低于开腹胃癌根治术,对于防止CEA和DDC介导的胃癌腹腔转移可能有一定作用.     

腹腔镜与开腹直肠癌全系膜切除术的对照研究

目的 比较腹腔镜与开腹直肠癌全系膜切除术的疗效,评价腹腔镜直肠癌全系膜切除术的可行性与安全性.方法 将2004-2007年收治的25例腹腔镜直肠癌根治术(Dixon)作为实验组,并按年龄、性别、肿块下缘距肛门距离、Dukes分期等匹配条件从同期开腹直肠癌手术(Dixon)中抽取25例作为对照组,比较两组的手术风险、术后恢复和随访结果.数据采用t检验、X~2检验.结果腹腔镜组25例中1例转改良Bacon手术.两组手术时间分别为(197±36)min和(172±51)min,差异有统计学意义(t=2.12,P=0.04).术中平均出血量分别为(157±105)ml和(304±237)ml,腹腔镜组明显少于开腹组(t=-2.95,P=0.01).两组肠段切除长度和清扫淋巴结数目比较,差异无统计学意义(t值分别为1.94、-0.77,P>0.05).肠道功能恢复的时间:腹腔镜组为(2.9±0.9)d,开腹组为(4.3±1.2)d,两组差异有统计学意义(t=-4.04,P=0.00).术后并发症发生率分别为16%和28%,两组差异无统计学意义(X~2=1.05,P=0.31).局部复发率分别为8%和4%,两组差异无统计学意义.结论 腹腔镜直肠癌全系膜切除术安全、可行,创伤小,远期疗效与开腹手术相近.     

腹腔镜肝切除术治疗肝癌病人的效果及对应激反应、T淋巴细胞的影响

目的探讨腹腔镜肝切除术(LLR)治疗原发性肝细胞癌的临床效果及对病人应激反应、T淋巴细胞水平的影响。方法选取我院确诊手术治疗的原发性肝细胞癌病人102例,根据手术方法不同分为腹腔镜组50例、开腹组52例,比较两组的手术时间、手术失血量、切口长度、引流管放置时间、住院时间,手术前后病人外周血白细胞(WBC)、中性粒细胞(NG)、T淋巴细胞及血清皮质醇水平变化。结果腹腔镜组和开腹组手术时间分别为(241.8±22.5)分钟和(216.2±24.7)分钟,腹腔镜组手术失血量为(385.0±64.1)ml、切口长度(4.8±1.0)cm、引流管放置时间(4.3±1.0)天、住院时间(8.2±1.5)天,开腹组分别为(528.0±80.5)ml、(25.6±3.4)cm、(7.1±1.6)天和(15.2±2.6)天,两组比较差异有统计学意义(P0.05);术后24小时,腹腔镜组病人的WBC为(11.36±2.15)×10~9/L、NG为(8.46±2.57)×10~9/L、皮质醇为(281.5±52.0)nmol/L,开腹组分别为(13.54±2.57)×10~9/L、(10.04±2.85)×10~9/L、(332.8±66.4)nmol/L,两组比较差异有统计学意义(P0.05);术后24小时,腹腔镜组病人的CD3~+(52.6±4.0)%、CD4~+(34.7±3.1)%、CD4~+/CD8~+(1.26±0.15)%,开腹组分别为(50.0±4.1)%、(32.4±2.9)%、(1.11±0.16)%,两组比较差异有统计学意义(P0.05),腹腔镜组的CD8~+(27.5±2.8)%低于开腹组(29.3±3.1)%(P0.05);腹腔镜组病人的手术并发症率(10.0%)低于开腹组(30.77%),差异有统计学意义(P0.05)。结论 LLR治疗原发性肝细胞癌的近期临床效果与开腹手术具有相当的效果,但是对病人的应激影响、细胞免疫功能影响更小,并发症率更低。     

腹腔镜根治性手术治疗肥胖直肠癌患者的安全性及近期疗效

目的 探讨新疆地区肥胖直肠癌患者行腹腔镜直肠癌根治术的安全性、可行性及近期疗效.方法 回顾性分析2008年4月至2012年4月新疆医科大学附属肿瘤医院收治的205例行根治性手术的肥胖直肠癌患者的临床资料,按手术方式以及体质指数进行分组:腹腔镜组95例(Ⅰ度肥胖60例、Ⅱ度肥胖35例),开腹组110例(Ⅰ度肥胖65例、Ⅱ度肥胖45例).对比分析腹腔镜组和开腹组患者术中和术后情况及近期生存情况.患者采用邮件和电话等方式进行随访,随访截至2012年6月.计量资料比较采用t检验,计数资料比较采用x2检验或Fisher确切概率法.应用Kaplan-Meier法绘制生存曲线,采用Log-rank 检验分析生存情况.结果 Ⅰ度肥胖患者中腹腔镜组和开腹组的手术时间分别为(235±25) min和(241±23) min,淋巴结清扫数目分别为(19±6)枚和(19±6)枚,两组比较,差异无统计学意义(t=-1.416,0.100,P＞0.05);术中出血量、肛门排气时间、术后住院时间、总并发症发生率分别为(195±77) ml、(1.7±0.6)d、(10.9±2.3)d、21.7％(13/60)和(393±170)ml、(3.8±1.1)d、(15.2±2.6)d、38.5％(25/65),两组比较,差异均有统计学意义(t=-8.229,-12.192,-12.002,x2=4.159,P＜0.05).Ⅱ度肥胖患者中腹腔镜组和开腹组的手术时间分别为(242 ±24) min和(250±23) min,淋巴结清扫数目分别为(17±5)枚和(18±7)枚,两组比较,差异无统计学意义(t=-1.556,-0.397,P＞0.05);术中出血量、肛门排气时间、术后住院时间、总并发症发生率分别为(253±96)ml、(1.8±0.7)d、(11.2 ±2.5)d、17.1％ (6/35)和(443±180)nl、(4.2±1.2)d、(16.2±2.4)d、37.8％ (17/45),两组比较,差异均有统计学意义(t=-5.634,-11.205,-8.824,x2=4.092,P＜0.05).本组185例患者获得随访,中位随访时间为23个月,腹腔镜组与开腹组患者累积生存率比较,差异无统计学意义(x2=0.203,P＞0.05).结论 肥胖直肠癌患者行腹腔镜直肠癌根治术安全可行,能满足肿瘤根治的需要,不影响患者的生存时间.     

完全腹腔镜下脾切除联合贲门周围血管离断术治疗门静脉高压症的疗效评价

目的 比较完全腹腔镜与开腹巨脾切除联合贲门周围血管离断术治疗肝硬化门静脉高压症的临床疗效. 方法 回顾性分析2004年12月至2006年12月对20例肝硬化门静脉高压症食管静脉曲张患者行完全腹腔镜下二级脾蒂离断法脾切除联合贲门周围血管离断术,另20例患者行传统开腹手术.比较两组的手术时间、术中出血量、术后并发症和术后住院时间等资料.结果 腹腔镜组与开腹组平均手术时间分别为(235±79)min和(230±99)min(P=0.068),平均术中出血量分别为(520±386)ml和(1856±1799)ml(P=0.018).腹腔镜组术后发生胸腔积液3例,膈下脓肿1例,轻度腹水2例;开腹组术后发生胸腔积液2例,腹腔积液2例,切口感染2例,门静脉血栓形成1例.并发症发生率分别为30%和35%,两组之间比较差异无统计学意义(P=0.639).术后两组均无死亡病例.两组术后血小板均升至100×109/L以上.腹腔镜组和开腹组平均住院时间分别为(8.5±2.6)d和(14.5±7.4)d(P=0.018).术后随访6～24个月,未再次发生上消化道出血.结论 完全腹腔镜下脾切除联合贲门周围血管离断术比开腹手术术中出血少,住院时间短,具于微创优势,值得推广应用.     

铜绿假单胞菌制剂腹腔给药对进展期胃癌患者细胞免疫水平的影响

目的 评价术中铜绿假单胞菌注射液腹腔置药对胃癌患者细胞免疫功能的影响及安全性.方法 将72例进展期胃癌患者随机分为铜绿假单胞菌腹腔置药组(实验组,41例)和对照组(31例).实验组术毕于瘤床放置铜绿假单胞菌注射液8～10ml.分别在术前、术后10、20、30 d采集两组患者的静脉血测定淋巴细胞总数、淋巴细胞亚群,观察患者围手术期并发症及药物不良反应.结果 实验组淋巴细胞总数[(1.77±0.58)×109/L]与对照组[(1.61±0.52)×109/L]比较明显提高,差异有统计学意义(P=0.042);实验组CD3+细胞(76.36±9.47)与对照组(68.63±10.34)比较明显提高,差异有统计学意义(P=0.027);实验组NK细胞(14.92±8.65)与对照组(14.61±10.31)比较明显提高(P=0.012),差异有统计学意义(P=0.027);实验组CD8+细胞(30.89±9.89)与对照组(30.53±9.26)比较明显下降,差异有统计学意义(P-0.037),而两组的CD4+细胞数和CD4+/CD8+相比差异无统计学意义(均P＞0.05).铜绿假单胞菌注射液对患者的血常规及肝、肾功能均无明显影响,实验组的1年生存率(94.9％)高于对照组(83.3％),两组相比差异有统计学意义(P=0.022).结论 铜绿假单胞菌注射液的腹腔给药方式安全可行,对进展期胃癌患者具有明显的免疫调节作用.     

腹腔镜直肠癌手术的疗效分析

目的 探讨腹腔镜直肠癌手术的安全性和临床疗效.方法 前瞻性分析2004年5月至2008年7月山西省肿瘤医院收治的347例直肠癌患者的临床资料.采用抽签法将患者分成腹腔镜组和开腹组,其中3例自动退出试验,1例腹腔镜组患者中转开腹剔除本试验,最终169例纳入腹腔镜组,174例纳入开腹组.观察指标包括肿瘤直径,淋巴结清扫数目,标本切除长度,平均手术时间,术中输血例数,术后下床活动时间,术后肛门排气、排便和进食流质食物时间,并发症等.统计分析遵循意向治疗原则,采用Kaplan-Meier法计算生存率,t检验和x2检验分析数据.结果 腹腔镜组与开腹组患者的肿瘤直径、淋巴结清扫数目、标本切除长度和术中输血例数分别为(4.3±1.3)cm、(7±5)枚、(19.1±2.2)cm、4例和(4.2±1.3)cm、(7±5)枚、(19.0±2.3)cm、8例,两组比较,差异无统计学意义(t=0.629,-0.726,0.562,x2=1.264,P＞0.05).腹腔镜组平均手术时间比开腹组长19 min,两组比较,差异有统计学意义(t=7.904,P＜0.05).腹腔镜组患者术后下床活动时间、术后肛门排气时间、术后排便时间和进食流质食物时间与开腹组比较,分别提前0.6、0.3、0.3、0.6 d(t=-6.392,-3.581,-3.802,-3.493,P＜0.05).两组术后感染、吻合口漏、肠梗阻和深静脉血栓等并发症比较,差异无统计学意义(x2=0.236,0.354,0.000,0.000,P＞0.05).截至2010年5月1日,腹腔镜组和开腹组分别有167例和172例患者获得随访.腹腔镜组和开腹组患者1年生存率分别为94.0%和95.3%,2年生存率分别为82.6%和91.2%,两组患者2年生存率比较,差异无统计学意义(x2=0.541,P＞0.05).腹腔镜组和开腹组患者平均生存时间分别为55.9个月和57.9个月.结论 腹腔镜直肠癌手术创伤小,术后恢复快,安全有效.     

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.