胸腹腔镜联合食管癌根治术后肺部并发症的危险因素分析

目的分析胸腹腔镜联合食管癌根治术后肺部并发症的危险因素,探讨肺保护性通气策略对肺部并发症的影响。方法行胸腹腔镜联合食管癌根治术患者348例,采用单因素和多因素分析方法探讨胸腹腔镜联合食管癌根治术后肺部并发症的独立危险因素。结果 348例患者肺部并发症的发生率为24.42%。多因素分析显示,高龄[优势比(OR)=3.934,95%可信区间(95%CI):1.431~9.478]、吸烟(OR=3.256,95%CI:1.204~8.863),术前合并糖尿病(OR=4.835,95%CI:1.454~11.562),术前合并慢性阻塞性肺疾病(OR=6.714,95%CI:1.528~13.762),肿瘤位于胸上段(OR=4.346,95%CI:1.447~10.382),术前合并低蛋白血症(OR=3.977,95%CI:1.344~9.896)是胸腹腔镜联合食管癌根治术后肺部并发症的危险因素,术中采取肺保护性通气策略(OR=0.273,95%CI:0.194~0.875)是胸腹腔镜联合食管癌根治术后肺部并发症的保护因素。结论通过分析食管癌术后肺部并发症发生的相关危险因素,发现肺保护性通气策略是胸腹腔镜联合食管癌根治术后肺部并发症发生的保护因素。     

食管癌根治食管胃颈部吻合术后吻合口漏的危险因素分析

目的分析食管癌根治术食管胃颈部吻合术后吻合口漏的危险因素分析。方法食管癌根治术食管胃颈部吻合术病人288例,根据术后吻合口漏发生情况分为吻合口漏组与非吻合口漏组,采用单因素及多因素Logistic回归分析术后吻合口漏的独立危险因素。结果 288例食管癌病人术后发生吻合口漏40例,发生率13.89%;单因素分析显示,两组合并呼吸系统疾病、术前放疗、术后肺部感染、支气管镜吸痰、制作管状胃、年龄、术前学清蛋白水平、手术时间比较差异有统计学意义(P0.05),性别、病理分型、TNM分期、肿瘤位置比较差异无统计学意义(P0.05);多因素Logistic回归分析显示,合并呼吸系统疾病(OR=4.114,95%CI:1.032～14.232)、术前放疗(OR=2.665,95%CI:1.004～8.986)、术后肺部感染(OR=3.033,95%CI:1.121～10.587)、制作管状胃(OR=3.323,95%CI:1.216～10.986)、支气管镜吸痰(OR=2.875,95%CI:1.125～9.343)是食管癌根治术食管胃颈部吻合术后吻合口漏的独立危险因素。结论食管癌根治食管胃颈部吻合术后吻合口漏发生率较高,合并呼吸系统疾病、术前放疗、术后肺部感染、支气管镜吸痰、制作管状胃等均会增加术后吻合口漏风险。     

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。     

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。     

食管癌根治术患者单/双肺通气术后肺部感染的发生情况

目的比较单/双肺通气对食管癌根治术患者术后肺部感染的影响。方法选择本院2009年1～12月收治349例行食管癌根治术患者,依据术中通气方式分为单肺通气组(OLV组)和双肺通气组(TLV组)。记录两组患者术后肺部感染率、住院时间以及术前、术中部分因素的差异。结果 OLV组患者术后肺部感染发生率显著高于TLV组(34.3%vs.24.6%,P<0.05),OLV住院时间明显长于TLV组[(27.1±9.1)dvs.(23.0±6.6)d,P<0.05]。结论在OLV条件下行食管癌根治术,患者的术后感染率明显高于TLV,并可能导致住院时间延长。     

不同麻醉镇痛方式对腹腔镜结直肠癌根治术患者术后转归的影响

目的比较不同麻醉镇痛方式对腹腔镜结直肠癌根治术患者术后转归的影响。方法选择择期行腹腔镜结直肠癌根治术患者122例,男60例,女62例,年龄26~85岁,BMI18.5~28.0kg/m2,ASAⅠ或Ⅱ级。采用随机数字表法随机分为三组:硬膜外镇痛组(EA组,n=40)、腹横肌平面阻滞组(TAP组,n=41)和静脉镇痛组(PCIA组,n=41)。三组全麻诱导维持用药相同,EA组行硬膜外阻滞和硬膜外镇痛,TAP组行双侧TAP阻滞,PCIA组予PCIA镇痛。记录三组患者七氟醚、舒芬太尼及血管活性药物用量。记录术后1h(T0)、6h(T1)、12h(T2)、24h(T3)、48h(T4)VAS评分及哌替啶用量。记录肠道功能恢复时间、进食时间、下床活动时间、住院时间,观察不良反应的发生情况。结果 PCIA组舒芬太尼用量、哌替啶追加次数明显多于,麻黄碱用量明显少于EA组和TAP组(P0.05)。EA组和TAP组各时点VAS评分明显低于PCIA组(P0.05),TAP组T3、T4时VAS评分明显高于EA组(P0.05)。TAP组和EA组肠道功能恢复时间、进食时间和下床活动时间均明显早于PCIA组(P0.05)。PCIA组恶心呕吐例数明显多于TAP组和EA组(P0.05)。结论全麻联合硬膜外镇痛、全麻联合腹横肌平面阻滞、全麻联合静脉镇痛对腹腔镜下结直肠癌根治术后患者镇痛效果依次降低;全麻联合硬膜外镇痛或腹横肌平面阻滞对患者术后转归有利。     

全麻联合硬膜外阻滞在腔镜食管癌根治术中的应用

目的探讨全麻联合硬膜外阻滞对腔镜食管癌根治术患者术后转归的影响。方法选择择期拟行腔镜食管癌根治术患者47例,男29例,女18例,年龄18~65岁,ASAⅠ或Ⅱ级,随机分为全麻联合硬膜外组(E组,n=24)和全麻组(G组,n=23)。E组患者在全麻诱导前行T8~9间隙硬膜外穿刺并置管,给予0.25%罗哌卡因5ml,出现麻醉平面后再行全麻诱导。两组均静注咪达唑仑0.03mg/kg、舒芬太尼1.0μg/kg、TCI丙泊酚以初始血浆药物浓度1.5μg/ml,当达到设定血浆药物浓度后以0.3μg/ml逐级递增,直至BIS稳定于60以下时静注罗库溴铵0.9mg/kg,行双腔气管导管插管。术中使用丙泊酚TCI、七氟醚补充吸入、瑞芬太尼持续输注、间断静脉注射顺式阿曲库铵维持麻醉。术中BIS维持在45~60;BP维持在基础值±20%之间;体温保护;限制性输液;单肺通气期间实施肺保护通气管理;术毕给予镇痛。E组使用硬膜外镇痛泵,G组使用静脉镇痛泵。记录入室时(T0)、插管后5min(T1)、手术开始后10min(T2)、单肺通气开始1h(T3)、单肺通气结束10min(T4)、手术结束即刻(T5)、拔管即刻(T6)、出PACU(T7)时的SBP、DBP、HR、SpO2,记录患者术中用药情况。记录术后第1、3天短期并发症发生情况与静息痛VAS评分;于术前1d和术后第7天对患者认知功能进行评估。结果E组拔管时间、PACU时间、住院时间明显短于G组(P0.05);E组T4~T6时的SBP明显低于G组(P0.05),T5时的DBP明显低于G组(P0.05),T6、T7时的HR明显慢于G组(P0.05);E组术中瑞芬太尼用量明显少于G组(P0.05),去氧肾上腺素用量明显多于G组(P0.05);E组术后躁动发生率明显低于G组(P0.05);E组在术后第1、3天的静息痛(VAS)评分明显低于G组(P0.05);E组术后第7天认知功能障碍(POCD)发生率明显低于G组(P0.05)。结论全麻联合硬膜外阻滞可明显改善食管癌患者术后恢复质量与认知功能损伤,但对患者长期转归影响仍需继续观察。     

胸腔镜部分肺切除术后肺部并发症的危险因素

目的探讨胸腔镜部分肺切除术后肺部并发症(PPCs)的危险因素。方法回顾性分析2018年1—12月首次行胸腔镜解剖性部分肺切除手术患者896例,年龄18～79岁,ASAⅠ—Ⅲ级,术前所有患者肺功能正常。收集患者性别、年龄、BMI、合并症、术中出入量及PPCs等围术期资料。采用单因素分析及多因素Logistic回归分析法筛选胸腔镜部分肺切除PPCs的危险因素。结果有220例(24.6%)患者发生PPCs(并发症组),其中最常见的肺炎有135例(15.1%)。单因素分析显示,并发症组患者术前白蛋白35 g/L、右肺手术、多肺叶肺段手术的比例明显高于无并发症组(P0.05),单肺通气时间明显长于无并发症组(P0.05),液体入量明显少于无并发症组(P0.05)。多因素Logistic回归分析显示,单肺通气时间2 h(OR=1.605,95%CI 1.113～2.314,P=0.011)、白蛋白35 g/L(OR=1.806,95%CI 1.094～2.981,P=0.021)、右肺手术(OR=1.443,95%CI 1.043～1.998,P=0.027)、多肺叶肺段手术(OR=1.998,95%CI 1.348～2.932,P=0.001)是胸腔镜部分肺切除PPCs的独立危险因素。结论单肺通气时间延长(2 h)、低白蛋白血症(白蛋白35 g/L)、右肺手术及接受多肺叶肺段手术可作为胸腔镜部分肺切除PPCs的独立危险因素。     

地佐辛复合舒芬太尼术后静脉自控镇痛疗效的Meta分析

目的:采用Meta分析评价地佐辛复合舒芬太尼用于腹部手术术后患者静脉自控镇痛(PCIA)的临床疗效。方法:系统检索Pub Med、Embase、Cochrane图书馆、CNKI、维普、万方等数据库,收集地佐辛复合舒芬太尼用于术后镇痛的临床研究文献,采用Rev Man5.0软件进行Meta分析。结果:共纳入16项临床试验,1277例患者。舒芬太尼复合地佐辛组在术后2 h患者的VAS评分较单用舒芬太尼的低,且有统计学意义[WMD=-0.16,95%CI(-0.27,-0.06)];舒芬太尼复合地佐辛组同单用舒芬太尼组比较Ramsay镇静评分没有统计学差异。舒芬太尼复合地佐辛组在术后2 h、48 h BCS舒适度评分较单用舒芬太尼组高,且具有统计学意义[WMD=-0.15,95%CI(-0.26,-0.05);WMD=0.24,95%CI(0.10,0.37)];舒芬太尼复合地佐辛组恶心呕吐、嗜睡、头痛头晕眩晕等不良反应发生率降低。舒芬太尼复合地佐辛镇痛效果满意度明显优于单用舒芬太尼组,且差异具有统计学意义[OR=2.56,95%CI(1.36,4.80),P<0.05]。结论:术后PCIA将地佐辛与舒芬太尼复合能得到满意的临床镇痛效果,同时能够降低不良反应的发生率。     

超声引导下腰骶丛神经阻滞联合全麻在高龄患者髋关节置换术的临床应用

目的观察超声引导下腰骶丛神经阻滞联合全麻在老年髋关节置换术的临床应用效果。方法择期行单侧髋关节置换术的老年患者80例,男35例,女45例,年龄65~85岁,随机均分为全麻组(G组)和腰骶丛神经阻滞联合全麻组(N组)。G组行全凭静脉麻醉,N组在超声引导下实施腰丛、骶丛神经阻滞后行无肌松静脉麻醉,两组均采用喉罩通气。术中两组均维持BIS 45~55,记录术中舒芬太尼用量、术后拔管时间、下床活动时间和出院时间;记录术后2、4、8、24h疼痛VAS评分及术后24h静脉自控镇痛(PCA)药物用量,并记录术后30d死亡率,对术后认知功能障碍(POCD)和术后谵妄(POD)情况和术后心血管和肺部并发症进行评估。结果术后30d两组患者均无死亡。N组患者术中舒芬太尼的使用量、PCA药物用量明显少于,术后拔管时间、下床活动时间和出院时间均明显短于G组(P0.05);术后2、4、8和24h时N组VAS评分明显低于G组(P0.05);G组1例患者术后出现严重肺部感染,术后N组POCD、POD发生率明显低于G组(P0.05)。结论与全麻比较,超声引导下腰骶丛神经阻滞联合全麻应用于老年髋关节置换术,减少了术中阿片类药物的用量,术后早期镇痛效果更好,明显缩短了下床活动时间和出院时间,且降低了老年患者POCD和POD的发生率。     

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.     

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.     

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.     

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.