无肌松药下靶控输注丙泊酚复合舒芬太尼腹部手术麻醉效果

观察无肌松药下靶控输注丙泊酚复合舒芬太尼对腹部手术的麻醉效果。2014年8月—2015年8月腹部手术100例,随机分为观察组和对照组各50例;观察组给予靶控输注丙泊酚复合舒芬太尼麻醉,对照组给予静脉推注丙泊酚复合芬太尼麻醉;记录给药前基础值(T_0)、意识消失时(T_1)、气管插管时(T_2)、手术时30 min和60 min(T_3、T_4)、意识恢复时(T_5)以及拔管时(T_6)患者的血流动力学指标,并观察患者恢复自主呼吸、恢复意识及拔管的时间以及不良反应发生情况。结果显示,与T_0相比较,T_1时2组患者各观察指标均下降,观察组BIS变化较为显著(P0.05);T_2时除BIS外,其余观察指标在T_1的基础上有不同程度上升,对照组SBP、MAP及HRV值较观察组上升明显(P0.05);T_(3-4)时,其余指标均进行性下降,对照组HR变化明显(P0.05);T_(5-6)时,各观察指标均开始逐渐上升,观察组BIS变化显著(P0.05)。结果表明,无肌松药下靶控输注丙泊酚复合舒芬太尼对腹部手术的麻醉诱导平稳,术中血流动力学稳定,麻醉效果良好,不良反应发生少。     

不同肌松程度对腹腔镜胆囊切除联合胆总管探查术患者视神经鞘直径的影响

目的观察不同肌松程度下腹腔镜胆囊切除联合胆总管探查术患者视神经鞘直径(ONSD)的变化。方法选择2020年6—12月择期全麻下行腹腔镜胆囊切除联合胆总管探查术的患者60例,男33例,女27例,年龄18～64岁,BMI 18～28 kg/m~2,ASAⅡ级。采用随机数字表法将患者分为两组:深度肌松组(S组)和中度肌松组(Z组),每组30例。术中根据TOF-Watch肌松监测仪,S组维持TOF计数为0且PTC计数1～2,Z组维持TOF计数1～2。记录手术时间、麻醉时间、罗库溴铵用量以及TOFr 0.9时间。记录诱导前即刻(T_0)、切皮前即刻(T_1)、气腹后30 min(T_2)、气腹后1 h(T_3)、放气后10 min(T_4)、出手术室前即刻(T_5)MAP、BIS、HR、ONSD及T_1—T_4时P_(ET)CO_2、PaCO_2、CVP。记录术后1 d恶心呕吐、头痛发生情况。结果两组手术时间、麻醉时间以及T_0—T_5时MAP、HR、BIS、P_(ET)CO_2、PaCO_2差异无统计学意义。与T_0时比较,T_2—T_5时两组ONSD明显增大(P0.05)。与T_1时比较,T_2—T_4时两组P_(ET)CO_2、PaCO_2、CVP均明显升高(P0.05)。与Z组比较,T_2—T_5时S组ONSD明显减小(P0.05),T_2—T_3时CVP明显降低(P0.05),TOFr 0.9时间明显延长(P0.05)。两组术后1 d恶心呕吐、头痛发生率差异无统计学意义。结论与中度肌松比较,深度肌松更能在一定程度上缓解腹腔镜胆囊切除联合胆总管探查术患者术中视神经鞘直径的增大。     

瑞芬太尼-丙泊酚无肌松药全身麻醉用于显微耳科手术的临床观察

目的探讨瑞芬太尼-丙泊酚无肌松药(NMB)气管插管全身麻醉用于显微耳科手术的安全性及可行性。方法选择慢性化脓性中耳乳突炎拟全麻下行显微镜下乳突根治术和鼓室成形术的患者60例,ASAⅠ-II级,随机分为无肌松组(NN组,n=30)和肌松组(N组,n=30)。顺序静脉注射舒芬太尼、丙泊酚、氯化琥珀胆碱气管插管后,NN组持续静脉输注丙泊酚、瑞芬太尼维持麻醉。N组持续静脉输注丙泊酚、瑞芬太尼、间断静脉注射维库溴铵维持麻醉。观察记录患者切皮前后(T1、T2)、电钻磨骨前后(T3、T4)以及拔管前后(T5、T6)HR、MAP、SpO2、EtCO2、Ppeak变化以及术中体动次数、麻醉苏醒及拔管时间、不良反应及并发症频次。结果两组患者T1、T2、T3、T4时HR、MAP、SpO2、Ppeak值对比差异无统计学意义(P0.05)。T5、T6时SPO2值NN组高于N组(P0.05),EtCO2、HR、MAP值N组高于NN组(P0.05)。术中所有患者无体动及呛咳反应。NN组麻醉苏醒时间和拔管时间明显短于N组,NN组不良反应及并发症发生率明显低于N组,差异均有统计学意义(P0.01)。结论瑞芬太尼-丙泊酚无肌松药全身麻醉用于显微耳科手术麻醉效果满意,苏醒快,安全可行。     

比较瑞芬太尼和芬太尼复合丙泊酚应用于腹腔镜胆囊切除术的麻醉效果

目的比较瑞芬太尼和芬太尼复合丙泊酚应用于腹腔镜胆囊切除术(LC)的麻醉效果。方法抽取2017-12—2018-09间在汝州市第一人民医院择期行LC的80例患者,随机分为2组,各40例。予以对照组芬太尼复合丙泊酚麻醉,观察组行瑞芬太尼复合丙泊酚麻醉。比较2组患者的:(1)诱导前(T_0)、气腹前(T_1)、手术开始10 min(T_2)及术毕时(T_3)的平均动脉压(MAP)、心率(HR)及血氧饱和度(SpO_2)等血流动力学指标。(2)自主呼吸恢复时间、拔管时间、睁眼时间。结果 (1)2组患者T_0时的MAP、HR与T_3时比较,及T_0时的SpO_2与T_1、T_2、T_3时比较,差异均无统计学意义(P0.05)。(2)2组患者T_1、T_2时MAP、HR均高于T_0时,差异均有统计学意义(P0.05);但观察组的MAP、HR低于对照组,差异有统计学意义(P0.05)。(3)观察组自主呼吸恢复时间、拔管时间、睁眼时间等均短于对照组,差异有统计学意义(P0.05)。结论对LC患者采取瑞芬太尼复合丙泊酚麻醉,对患者血流动力学的指标影响较小,术后苏醒质量高。     

舒芬太尼复合丙泊酚对小面积微创吸脂手术麻醉效果的研究

目的探讨舒芬太尼复合丙泊酚对小面积微创吸脂手术的麻醉效果。方法选择择期行双上臂、面颊部、腰腹部吸脂整形手术的患者各20例,随机分为舒芬太尼复合丙泊酚组(A组)和瑞芬太尼复合丙泊酚组(B组),每组30例。观察麻醉前(T_0)、麻醉后2 min(T_1)、注射肿胀液时(T_2)、手术开始20 min(T_3)及手术结束时(T_4)的平均动脉压(MAP)、心率(HR)及SpO_2的变化;记录两组患者静脉麻醉镇痛与镇静效果,并观察术中呼吸抑制、肢体活动、喉痉挛、清醒时间、呛咳、术后躁动及恶心呕吐等情况。结果两组患者术中丙泊酚用量差异无统计学意义(P0.05);与麻醉前相比,B组麻醉时MAP和HR下降较A组更显著(P0.05);SS组在麻醉维持期间MAP和HR较B组高(P0.05);T_1~T_3时间点,B组MAP和HR低于A组(P0.05);T_4时间点B组MAP和HR高于A组(P0.05);A组患者的清醒时间较B组长(P0.05);RR组呼吸抑制、术后躁动、恶心呕吐发生率较A组显著增多(P0.05)。结论舒芬太尼复合丙泊酚配合局部肿胀麻醉在小面积微创吸脂手术中的血流动力学更稳定,镇痛时间长,术中呼吸抑制少,术后躁动、恶心呕吐发生率低,值得在临床上推广。     

不同剂量麻黄碱对顺式阿曲库铵肌松效应的影响

目的 观察不同剂量麻黄碱对顺式阿曲库铵(Cis)肌松效应的影响.方法 患者75例,ASA Ⅰ或Ⅱ级,随机均分为三组:P1、P2和C组.P1组:1%丙泊酚+0.5 mg/ml麻黄碱,P2组:1%丙泊酚+0.75 mg/ml麻黄碱,C组:1%丙泊酚+相同容量的牛理盐水.记录肌松起效时间、肌松恢复时间、气管插管条件和插管期间的血流动力学变化.结果 P2组起效时间、95%恢复时间、肌松完全恢复时间、5～95%恢复指数明显快于C组(P＜0.05或P＜0.01).P2组在插管1 min时MAP明显上升,HR明显增快(P＜0.05);C组在插管即刻和插管1 min时MAP明显下降,HR明显减慢(P＜0.01).插管条件P2组明显好于C组(P＜0.05).结论 1%丙泊酚十0.75 mg/ml小剂量麻黄碱联合麻醉诱导后≤4 min时,再给予Cis 0.15 mg/kg可有效缩短起效时间和95%恢复时间,同时能够改善气管插管条件.     

二氧化碳气腹对腹腔镜手术患者顺阿曲库铵肌松效应的影响

目的 评价二氧化碳(C02)气腹对腹腔镜手术患者顺阿曲库铵肌松效应的影响.方法 择期子宫切除术患者60例,年龄35 ～ 60岁,BMI 18～ 24 kg/m2,ASA分级Ⅰ或Ⅱ级.采用随机数字表法,将其随机分为2组(n=30):气腹组(P组)和对照组(C组);每组根据肌松拮抗剂使用情况随机分为2个亚组(n=15):非拮抗组(P0组或C0组)和拮抗组(P1组或C1组).静脉注射芬太尼、丙泊酚、顺阿曲库铵麻醉诱导,气管插管后行机械通气.靶控输注丙泊酚和瑞芬太尼维持麻醉.采用TOF-Watch SX加速度仪监测肌松程度,P组于气腹建立后T1恢复达5％时静脉注射顺阿曲库铵0.05mg/kg,术毕P1组和C1组于 T1恢复至25％时静脉注射新斯的明拮抗,P0组和C0组自然恢复.记录气腹建立后追加顺阿曲库铵的临床作用时间和恢复指数.于诱导前即刻、气腹30 min、60 min及术毕时,分别抽取动脉血样行血 气分析.结果 与C0组比较,P0组临床作用时间及恢复指数延长(P＜0.05);与C1组比较,P1组临床作用时间及拮抗恢复指数延长(P＜0.05);与 C0组比较,P0组于气腹30、60 min、术毕时pH值下降,PaCO2升高(P＜0.05);与C1组比较,P1组于气腹30、60 min、术毕时pH值下降,PaCO2升高(P＜0.05).结论 CO2气腹可强化顺阿曲库铵的肌松效应,且可延长拮抗后肌松恢复时间.     

盐酸达克罗宁胶浆在患儿扁桃体切除术中的应用

目的观察盐酸达克罗宁胶浆对患儿扁桃体切除术围术期血流动力学、术后疼痛及苏醒期躁动的影响。方法选择2017年1月至2018年2月全麻下择期行双侧扁桃体切除术患儿60例,男39例,女21例,年龄3～10岁,BMI 10～34 kg/m~2,ASAⅠ或Ⅱ级。随机分为3组:单次用药组(SD组)、重复用药组(RD组)和对照组(CG组),每组20例。SD组麻醉前15 min含服5 ml盐酸达克罗宁胶浆5 min;RD组麻醉前15 min含服5 ml盐酸达克罗宁胶浆5 min,术毕前扁桃体窝内均匀涂抹盐酸达克罗宁胶浆2 ml;CG组麻醉前15 min含服5 ml空白胶浆5 min,术毕前扁桃体窝内涂抹空白胶浆2 ml,所有患儿均采用气管插管全麻。记录麻醉诱导前(T_0)、插管即刻(T_1)、扁桃体剥离时(T_2)、入PACU 30 min(T_4)、入PACU 60 min(T_5)时HR、MAP;记录麻醉时间、手术时间、苏醒时间、拔管时间,记录患儿入PACU时(T_3)、入PACU 30 min(T_4)、入PACU 60 min(T_5)时FLACC和PAED评分;记录术后恶心呕吐、创面渗血、呼吸道梗阻、低氧血症等不良反应发生情况。结果与T_0时比较,T_1、T_2时SD组和RD组HR明显减慢、MAP明显降低(P0.05),T_4、T_5时SD组HR明显增快、RD组MAP明显降低(P0.05),T_1、T_4和T_5时CG组HR明显增快(P0.05)。T_1、T_2时SD组和RD组HR明显慢于CG组,且MAP明显低于CG组(P0.05);T_4、T_5时RD组HR明显慢于SD组和CG组,且MAP明显低于SD组和CG组(P0.05)。T_3、T_4和T_5时,RD组的FLACC、PAED评分明显低于SD和CG组(P0.05)。三组患儿术后恶心呕吐、创面渗血、呼吸道梗阻、低氧血症等不良反应差异无统计学意义。结论患儿扁桃体切除术麻醉前和术毕应用盐酸达克罗宁胶浆,不仅明显减少围术期血流动力学波动,还可有效缓解患儿术后疼痛,减少苏醒期躁动。     

达米弱刺激通气型口垫在全身麻醉患者苏醒期的应用

目的观察达米弱刺激通气型口垫(达米口垫)作为一种创新型过渡性口咽通气道在麻醉苏醒期的安全性和有效性。方法选取行气管插管全身麻醉腹部手术且拔管后出现意识未完全恢复清醒、伴有舌后坠或呼吸不畅的患者200例,男153例,女47例,年龄26～66岁,体重42～91 kg,ASAⅠ—Ⅲ级。随机分为四组:达米口垫组(D组)、口咽通气道组(K组)、鼻咽通气管组(B组)和传统托颌组(C组),每组50例。拔管后气道管理措施:D组经口置入达米弱刺激通气型口垫;K组置入口咽通气道;B组经鼻置入鼻咽通气道;C组出现气道梗阻情况时予以托颌通气处理。记录拔除气管导管前即刻(T_0)、拔管后5 min(T_1)、拔管后10 min(T_2)、拔管后15 min(T_3)的血流动力学指标(HR、BP、SpO_2)、血气分析指标(PaCO_2、PaO_2、pH值);记录通气道留置时间、调整通气道次数,以及PACU停留时间、拔管后通气过程中舒适度。记录不良反应的发生情况。结果与D组比较,T_1时C组HR明显增快(P0.05),T_2时K组、C组HR明显增快(P0.05),T_3时K组HR明显增快(P0.05),T_2、T_3时K组、B组MAP明显升高(P0.05),T_3时B组、C组PaCO_2明显升高(P0.05),T_1—T_3时K组、B组、C组PaO_2明显降低(P0.05),T_2时C组、T_3时B、C组pH值明显升高(P0.05)。与T_0时比较,T_1时四组HR明显减慢,MAP明显降低(P0.05),T_2时D组HR减慢,D组、B组MAP明显降低(P0.05),T_3时K组、B组HR明显增快,MAP明显升高(P0.05),T_1—T_3时四组PaO_2、pH值明显降低,PaCO_2明显升高(P0.05)。四组不同时点SpO_2差异无统计学意义。与D组比较,K组通气道留置时间和调整通气道次数明显增多(P0.05),C组PACU停留时间明显延长(P0.05),K组、C组拔管后舒适度明显降低(P0.05)。C组躁动发生率明显升高(P0.05)。结论达米弱刺激通气型口垫在气管插管全身麻醉恢复期能够有效维持呼吸道的通畅,具有循环影响小、舒适度高、不良反应小等优点,优于传统口咽、鼻咽通气道。     

复合咪唑安定对丙泊酚靶控输注诱导的影响

目的 观察靶控输注(TCI)丙泊酚麻醉诱导中,维持脑电双频指数(BIS)为50时,复合咪唑安定对丙泊酚靶浓度及血流动力学的影响.方法 40例ASA Ⅰ或Ⅱ级拟行妇科腹腔镜手术病人,随机均分为丙泊酚(P)组和丙泊酚复合咪唑安定(M)组,记录BIS值降至50时的丙泊酚血浆及效应室靶浓度及病人诱导前、BIS值降至50时(诱导后)及气管插管即刻的HR和MAP.结果 当BIS值降至50时,M组丙泊酚的血浆及效应室靶浓度及用量均明显低于P组(P＜0.05或P＜0.01);两组病人诱导后的MAP均较诱导前明显降低(P＜0.01),P组诱导后、气管插管即刻的HR较诱导前明显减慢(P＜0.05或P＜0.01)且明显慢于M组(P＜0.05).结论 以BIS值降至50为指标.TCI丙泊酚诱导时复合咪唑安定可明显降低丙泊酚的血浆及效应室靶浓度;可减轻丙泊酚诱导所致HR减慢,但不能减轻丙泊酚诱导所致血压下降;对插管时血流动力学影响两者相似.     

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.