聚焦超声治疗婴幼儿血管瘤的初步临床应用

目的探讨聚焦超声治疗婴幼儿血管瘤临床效果及适宜能量参数。方法 2009年1月-2010年9月,收治60例血管瘤患儿。男23例,女37例;年龄3～30个月,平均10个月。病变部位:头面部24例,躯干15例,四肢16例,臀部2例,会阴部1例,颈部、腹部及上肢多发2例。瘤体范围为0.8 cm×0.6 cm～6.0 cm×5.0 cm。根据应用的聚焦超声能量不同,随机分成A、B、C 3组(n=20)。采用超声治疗仪以3～5 mm/s速度连续辐照血管瘤表面,频率9 MHz,脉冲1 000,重叠10%,扫描5个来回,A、B、C组功率分别为3.5、4.0、4.5 W;治疗3次为1个疗程,每次治疗间隔1个月,观察治疗结束6个月后效果及辐照区皮肤破溃、瘢痕发生率。结果所有患儿均完成1个疗程治疗,治疗结束6个月按照血管瘤疗效判定标准评定,各组比较差异无统计学意义(P>0.05)。A组无皮肤破溃及瘢痕;B组4例(20%)辐照区皮肤出现不同程度破溃,经换药后遗留浅表瘢痕;C组7例(35%)辐照区皮肤出现溃烂,经换药后遗留较明显瘢痕。B、C组皮肤破溃及瘢痕发生率均明显高于A组(P<0.05)。结论聚焦超声辐照是治疗婴幼儿血管瘤有效方法之一,能量以不超过3.5 W为宜。     

聚焦超声治疗婴幼儿血管瘤的初步临床应用

目的探讨聚焦超声治疗婴幼儿血管瘤临床效果及适宜能量参数。方法 2009年1月-2010年9月,收治60例血管瘤患儿。男23例,女37例;年龄3～30个月,平均10个月。病变部位:头面部24例,躯干15例,四肢16例,臀部2例,会阴部1例,颈部、腹部及上肢多发2例。瘤体范围为0.8 cm×0.6 cm～6.0 cm×5.0 cm。根据应用的聚焦超声能量不同,随机分成A、B、C 3组(n=20)。采用超声治疗仪以3～5 mm/s速度连续辐照血管瘤表面,频率9 MHz,脉冲1 000,重叠10%,扫描5个来回,A、B、C组功率分别为3.5、4.0、4.5 W;治疗3次为1个疗程,每次治疗间隔1个月,观察治疗结束6个月后效果及辐照区皮肤破溃、瘢痕发生率。结果所有患儿均完成1个疗程治疗,治疗结束6个月按照血管瘤疗效判定标准评定,各组比较差异无统计学意义(P>0.05)。A组无皮肤破溃及瘢痕;B组4例(20%)辐照区皮肤出现不同程度破溃,经换药后遗留浅表瘢痕;C组7例(35%)辐照区皮肤出现溃烂,经换药后遗留较明显瘢痕。B、C组皮肤破溃及瘢痕发生率均明显高于A组(P<0.05)。结论聚焦超声辐照是治疗婴幼儿血管瘤有效方法...     

聚焦超声治疗低级别宫颈上皮内瘤样病变

[摘要]目的探讨聚焦超声技术在治疗宫颈上皮内瘤样病变（CIN）Ⅰ-Ⅱ级中的应用价值。方法收集78例经病理学证实的CINⅠ级及Ⅱ级患者,行聚焦超声治疗,其中CINI级患者随机分为A1、A2及A3组,CIN Ⅱ级随机分为B1、B2及B3组,分别给予不同的辐照剂量,6个月后行液基薄层细胞学检查（TCT）,必要时行阴道镜或病理组织学检查。结果A3组患者治愈率为88．24％（15／17）,与A1、A2组差异均有统计学意义（P均〈0．0167）;B3组患者治愈率为81．82％（9／11）,与B1组治愈率的差异有统计学意义（P〈0．0167）,而与B2组差异无统计学意义（P〉O．0167）。结论采用适当治疗剂量的聚焦超声能够安全、有效地治疗低级别CIN。     

曲安奈德联合点阵激光及乳膏外涂序贯治疗增生性瘢痕的近远期疗效观察

目的:探讨曲安奈德联合点阵激光及乳膏外涂序贯治疗增生性瘢痕近远期的治疗效果。方法:选取笔者医院2014年5月-2017年5月收治的90例增生性瘢痕患者,根据随机数字表法分成A组、B组、C组,每组30例。A组:采用曲安奈德序贯点阵激光治疗;B组:采用点阵激光联合乳膏外涂治疗;C组:采用曲安奈德联合点阵激光及乳膏外涂序贯治疗。比较三组治疗后3、6个月的临床疗效,分别在患者治疗前及治疗后3、6个月测定瘢痕体积与血红素、黑色素含量,并取瘢痕组织检测转录因子63(Protein63,P63)、角蛋白19(Cytokeratin19,CK19)在其中的强阳性表达率。结果:C组治疗后3个月的总有效率为93.33%,高于A、B组的73.33%,差异有统计学意义(P0.05),A、B、C组治疗后6个月的总有效率分别为93.33%、96.67%、100.00%,组间比较无统计学意义(P0.05)。三组治疗后3、6个月,瘢痕体积及血红素、黑色素含量均低于治疗前,且C组治疗后3个月的瘢痕体积、黑色素含量低于A、B组,差异有统计学意义(P0.05)。三组治疗后3、6个月的P63、CK19强阳性表达率高于治疗前,且C组治疗后3个月两者强阳性表达率高于A、B组,差异有统计学意义(P0.05)。A、B组患者均未出现不良反应,C组不良反应发生率为6.67%,三组不良反应发生率比较无统计学意义(P0.05)。结论:曲安奈德联合点阵激光与乳膏外涂序贯治疗能促进增生性瘢痕患者病情的改善,近远期效果均比较理想,不良反应少,安全性高。     

连续和脉冲高强度聚焦超声辐照离体牛晶状体致凝固性坏死的变化过程

目的观察连续高强度聚焦超声(CHIFU)与脉冲高强度聚焦超声(PHIFU)辐照离体牛晶状体所致凝固性坏死的变化过程,分析占空比对高强度聚焦超声(HIFU)辐照结果的影响。方法将80个离体牛晶状体分为4组行HIFU辐照,声功率均为500W,脉冲重复频率均为4Hz,A组(CHIFU组),占空比100%,辐照时间1s;B组,占空比50%,辐照时间2s;C组,占空比20%,辐照时间5s;D组,占空比10%,辐照时间10s。以高速摄影设备和被动空化采集(PCD)系统记录凝固性坏死的发生过程和焦域处发出的声散射信息,测算各组凝固性坏死体积,并对空化行为进行分析。结果 A组(CHIFU组)凝固性坏死出现的平均时间为0.41s,B、C、D组分别为0.93、2.22、6.28s;CHIFU辐照凝固性坏死出现时间早于PHIFU辐照。各组辐照后形成的凝固性坏死形态有所不同。A组(CHIFU组)凝固性坏死体积随辐照时间呈线性增长,B、C、D组凝固性坏死体积均呈非线性增长。辐照结束后,A组(CHIFU组)凝固性坏死体积为(12.99±2.11)mm3,B组为(12.69±1.79)mm3,C组为(12.09±1.93)mm3,D组为(6.94±1.54)mm3。D组凝固性坏死体积均小于其余3组(P均0.05),A、B、C组间两两比较差异无统计学意义(P均0.05)。各组均有空化发生,A组(CHIFU组)幅度均方根值(RMS)曲线有突然增大的过程,B、C、D组RMS曲线呈周期性的变化,占空比越高,空化行为越剧烈。结论CHIFU与PHIFU辐照所致牛晶状体凝固性坏死发生发展过程不同,调节HIFU辐照的占空比可影响凝固性坏死出现的时间及体积。     

血管内皮抑素微泡联合聚焦超声抗结肠癌肿瘤血管生成的实验研究

目的评估靶向载血管内皮抑素微泡联合改良聚焦超声定向辐照抑制结肠皮下易位原位结肠癌肿瘤血管生成的治疗效果。方法将65只结肠皮下易位原位结肠癌肿瘤的Balb／c裸鼠模型随机分为5组,每组13只：A组为空白对照组,裸鼠肿瘤未行任何治疗组;B组为单纯超声辐照组,仅行超声辐照,未使用任何造影剂;C组为超声辐照联合SonoVue裸微泡治疗组;D组为超声辐照联合Targestar．SA裸微泡治疗组;E组为超声辐照联合包载血管内皮抑素的微泡治疗组。分别于辐照前、辐照后1、14和28d测量肿瘤体积,绘制肿瘤体积生长曲线。实时超声造影检查,脱机分析峰值强度（PI）、局部血容量（RBV）和局部血流量（RBF）等造影参数。实验结束后切除肿瘤组织行光镜及电镜病理学检查,并通过CD34免疫组织化学检测评估肿瘤坏死面积（NA）和微血管密度（MVD）。结果辐照前各组肿瘤体积的差异无统计学意义（P〉O．05）;辐照后28d,C组、D组和E组肿瘤体积明显小于A组和B组,且E组明显小于c组和D组（均P〈0．01）。辐照前各组PI、RBV和RBF的差异均无统计学意义（均P〉0．05）;辐照后28d,C组、D组和E组PI、RBF和RBV较辐照前明显降低且明显低于A组和B组（均P〈0．05）,E组明显低于C组和D组（均P〈0．05）。电镜观察显示,C、D、E组肿瘤细胞核膜消失,核染色质溶聚,呈簇状不规则排列,线粒体空泡化和微血管内皮损伤出血,以E组最为明显,而A和B组鲜见。免疫组织化学染色显示,治疗后28d,E组肿瘤组织NA明显高于其他各组,而MVD则明显低于其他各组（均P〈0．01）。结论靶向载血管内皮抑素微泡联合改良聚焦超声定向辐照可以破坏结肠皮下易位原位结肠癌肿瘤微血管,并抑制肿瘤新生血管生成,增强结肠癌的治疗效果．将来可能是具有临床应用前景的结肠癌治疗新方法。     

A型肉毒毒素联合复方倍他米松治疗大面积增生性瘢痕的临床疗效观察

目的探讨A型肉毒毒素联合复方倍他米松治疗大面积增生性瘢痕的临床效果。方法回顾性分析2017年3月至2019年3月于北部战区总医院烧伤整形科收治的39例大面积增生性瘢痕患者的临床资料,根据采用的治疗方法分为A组:A型肉毒毒素联合复方倍他米松瘢痕内注射组(13例);B组:A型肉毒毒素瘢痕内注射组(12例);C组:复方倍他米松瘢痕内注射组(14例)。记录治疗的总有效率,参照温哥华瘢痕评分量表(vancouver scar score sheet,VSS)对3组患者的瘢痕色泽、血管分布、柔软度进行综合评分;采用彩色多普勒超声诊断仪测量瘢痕厚度,并参照视觉模拟评分量表(visual analogue scale,VAS)评价患者的痛痒觉改善情况;记录不良反应发生情况;随访6个月。结果A组的总有效率(92.31%)、VSS值、瘢痕厚度、VAS值评价均明显优于B组(75.00%)和C组(50.00%),其差异有统计学意义(P<0.05)。A、B组经3次治疗后,痛痒症状明显缓解,病情趋于稳定。治疗6个月随访时A组患者未再复发,B组复发2例。3组中有极个别患者在治疗后偶发针孔周围皮肤红肿,于1~2 d自行缓解,未发生严重的不良反应。结论A型肉毒毒素联合复方倍他米松治疗大面积增生性瘢痕安全有效,能提高单次治疗的有效面积及效果并减少激素用量及其并发症,值得临床推广应用。     

不同间隔时间脉冲染料激光治疗痤疮瘢痕的疗效观察

目的：探讨不同间隔时间脉冲染料激光(Pulsed dye laser,PDL)治疗痤疮瘢痕的临床疗效。方法：回顾性分析2018年8月-2020年10月笔者科室采用PDL治疗的150例痤疮瘢痕患者病例资料，按照治疗周期不同分为A组(50例)、B组(51例)和C组(49例)，A组每2周治疗一次，B组每3周治疗一次，C组每4周治疗一次，共治疗3个月，比较治疗前后三组患者的痤疮瘢痕疗效、VISIA面部检测、皮肤生理指标及瘢痕恢复情况。结果：B组治疗后总有效率为78.43%，高于A组和C组(χ²=7.594,P<0.05);B组治疗后色斑、皱纹、纹理、毛孔及紫质均低于A组和C组，差异具有统计学意义(P<0.05);B组患者治疗后红斑指数、黑素指数及TEWL低于A组和C组，角质层含水量高于A组和C组，差异具有统计学意义(P<0.05);B组患者治疗后的红斑持续时间、水肿时间及创面疼痛消退时间低于A组和C组，差异具有统计学意义(P<0.05)。结论：间隔时间为3周的脉冲染料激光治疗痤疮瘢痕可以快速促进成纤维细胞生成真皮胶原蛋白，降低瘢痕增生和VISIA分...     

气压弹道式冲击波联合康复训练治疗足底筋膜炎的疗效观察

目的观察气压弹道式冲击波联合康复训练治疗足底筋膜炎的临床疗效。方法纳入自2017-01—2018-07诊治的60例足底筋膜炎,30例采用气压弹道式冲击波联合康复训练治疗(A组),30例采用超声引导下注射局部麻醉药物、类固醇激素联合康复训练治疗(B组)。结果 60例均获得至少6个月随访,治疗后1周疼痛NRS评分较治疗前明显降低,治疗后3个月足底筋膜厚度较治疗前减小。A组治疗后1周、1个月疼痛NRS评分高于B组,治疗后3个月疼痛NRS评分低于B组,治疗后3个月足底筋膜厚度小于B组,差异有统计学意义(P0.05)。A组(93.3%)治疗后3个月有效率高于B组(70.0%),差异有统计学意义(P0.05)。A组2例出现冲击部位皮肤轻度肿胀,1例出现冲击部位轻度疼痛,未特殊处理,1周后自行好转。B组3例注射部位局部肿胀,未特殊处理,1周后自行好转。结论气压弹道式冲击波联合康复训练治疗足底筋膜炎具有疼痛缓解持久、有效率高、不良反应少、安全可靠等优点。     

麦默通微创旋切术后应用四种创口处理方式改善切口美容效果的临床观察

目的:对比麦默通微创旋切术后,不处理、丝线缝合、拉合胶粘合和组织胶水粘合四种不同创口闭合方式的效果。方法:选取我院1年内收治600例接受麦默通微创旋切术的患者,根据术后创口处理方式随机分为4组,A组不处理、B组丝线缝合、C组拉合胶粘合和D组组织胶水粘合,并于术后1周和3个月时进行随访,调查患者术后可洗澡时间、青紫发生率、术后瘢痕大小和患者满意度,根据以上四方面,综合比较出最佳的创口闭合方式。结果:D组与A、B、C组相比较,可洗澡时间明显缩短,差异具有统计学意义(P0.05);术后各组青紫率相似,差异无统计学意义(P0.05);D组与A、B、C组比较,瘢痕明显较小,差异具有统计学意义(P0.05);D组与A、B、C组比较,具有最高的患者满意度。结论:麦默通微创旋切术后四种创口处理方式中,组织胶水粘合皮肤和其他三种方法相比,可明显缩小瘢痕,具有较早的术后可洗澡时间和较高的患者满意度,从而认为组织胶水粘合皮肤为最佳的创口处理方法,值得临床推广应用。     

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.