异氟醚控制性降压对颅内动脉瘤夹闭术病人脑脊液游离脂肪酸浓度的影响

目的探讨异氟醚控制性降压对颅内动脉瘤夹闭术病人脑脊液游离脂肪酸(FFAs)浓度的影响。方法择期行颅内动脉瘤夹闭术病人30例,ASAⅠ级或Ⅱ级,随机分为2组(n=15):对照组(A组)和控制性降压组(B组)。2组均在术中持续吸入异氟醚维持麻醉,A组术中呼气末异氟醚浓度为1.2%;B组切开硬脑膜时开始行异氟醚控制性降压,平均动脉压(MAP)下降幅度为基础值的30%～40%,夹闭动脉瘤即刻开始降低异氟醚吸入浓度停止控制性降压,使血压回升至降压前水平。分别于麻醉诱导前(T_0)、硬脑膜切开即刻(T_1)、硬脑膜切开后10、20、30min(T_(2-4))、动脉瘤夹闭后即刻(T_5)、动脉瘤夹闭后10、20、30min(T_(6～8))记录血液动力学指标;于T_1、L_5动脉瘤夹闭后2、4h(T_(9.10))取脑脊液,测定FFAs浓度。结果(1)B组硬脑膜切开后MAP由(96±9)mm Hg降至(62±4)mm Hg(P<0.05或0.01),夹闭动脉瘤后MAP恢复至(78±11)mm Hg,心输出量和心率无明显变化(P>0.05)。(2)B组在T_5、T_9、T_(10)时脑脊液FFAs浓度增高(P<0.05),B组FFAs浓度增高的程度高于A组(P<0.05)。结论异氟醚控制性降压可以增加颅内动脉瘤夹闭术病人脑脊液中FFAs的浓度。     

异氟醚控制性降压对颅内动脉瘤夹闭术病人脑脊液中S100B蛋白含量的影响

目的 对颅内动脉瘤夹闭术病人采用异氟醚控制性降压,测定动脉瘤夹闭前后脑脊液中S100B蛋白含量,研究异氟醚控制性降压对脑功能的影响。方法 择期颅内动脉瘤夹闭术病人30例,ASA Ⅰ～Ⅱ级,随机分为两组:异氟醚降压组(n=15)和异氟醚非降压组(n=15)。非降压组术中吸入异氟醚维持麻醉,呼气末浓度为1.2％。降压组行异氟醚控制性降压,平均动脉压下降幅度30％～40％,夹闭动脉瘤后降低异氟醚吸入浓度,终止降压。分别于降压前、降压后30 min、动脉瘤夹闭后即刻、停止降压后30 min(非降压组于相应时间)测定循环指标变化;于降压前、动脉瘤夹闭后即刻、2、4 h取脑脊液测定S100B蛋白含量。结果 (1)异氟醚降压后30min平均动脉压由诱导前的(95±12)mm Hg降至(59±5)mm Hg,停止降压后30 min血压回升至(75±8)mm Hg。降压后外周血管阻力及心肌收缩加速度下降,但心率及心输出量均无显著性变化。(2)降压组动脉瘤夹闭后4 h脑脊液中S100B浓度明显高于非降压组(P<0.01),而非降压组脑脊液中S100B浓度轻微升高(P<0.05)。结论 在颅内动脉瘤夹闭术中应用异氟醚控制性降压可能加重了术后脑损伤,不利于病人围麻醉期脑功能的保护。     

右美托咪啶和硝酸甘油控制性降压在颅内动脉瘤夹闭术中的比较

目的 比较在颅内动脉瘤夹闭术中右美托咪啶或硝酸甘油控制性降压的效果及对脑氧代谢的影响. 方法 60例行颅内动脉瘤夹闭术患者,采用随机数字表法分为右美托咪啶组(D组)和硝酸甘油组(N组).D组泵注右美托咪啶,首剂量1.0 μg/kg(泵注10 min),0.4 μg·kg-1·h-1～0.8 μg·kg1·h-1维持；N组泵注硝酸甘油,首剂量3μg·kg-1·min-1,10 min后3μg·kg-1· h-1～9μg· kg-1· min-1维持.记录麻醉诱导前(T),控制性降压开始后0(T0)、10(T1)、20(T2)、30 min(T3)和停止降压后30 min(T4)的平均动脉压(MAP)、心率(HR),同时采集桡动脉血和颈内静脉球部血行血气分析,计算脑氧摄取率(cerebral oxygen extraction rate,CERO2). 结果 实施控制性降压后,两组MAP均在30 min内达到目标血压.降压期间,HR:D组T3时(66±10)次/ min低于T0时(76±9)次/min(P＜0.05),N组T3时(86±8)次/min高于T0时(77±8)次/min(P＜0.05)；CERO2:D组T3时(27±6)％低于T0时(35±6)％(P＜0.05)；N组T3时(32±6)％与T0时(34±5)％差异无统计学意义(P＞0.05).D组CERO2与MAP呈正相关(r=0.83).结论 右美托咪啶用于颅内动脉瘤术中控制性降压安全、可靠.与硝酸甘油比较,有减慢HR,降低术中脑氧代谢率的优点.     

异氟醚控制性降压对颅内动脉瘤夹闭术血中S100B含量的影响

目的　测定颅内动脉瘤夹闭前后血中S1 0 0B蛋白含量 ,研究异氟醚控制性降压对脑功能的影响。方法　择期颅内动脉瘤夹闭术病人 30例 ,ASAⅠ～Ⅱ级 ,随机分为两组 :异氟醚降压组 (n=1 5 )和异氟醚非降压组 (n =1 5 )。非降压组术中吸入 1MAC异氟醚维持麻醉。降压组行异氟醚控制性降压 ,平均动脉压下降幅度 30 %～ 4 0 % ,夹闭动脉瘤后降低异氟醚吸入浓度 ,终止降压。分别于切皮前、动脉瘤夹闭后即刻、2、4h、术后第 1、2天取血测定S1 0 0B蛋白含量 ,并于术后 1周随访病人 ,记录有无术后神经系统并发症。结果　 (1 )异氟醚降压后 30min平均动脉压由诱导前的 (95 2± 1 2 3)mmHg降至 (5 8 8± 5 4 )mmHg ,停止降压后 30min血压回升至 (75 1± 8 3)mmHg。降压后外周血管阻力及心肌收缩加速度下降 ,但心率及心输出量均无显著性变化 ;(2 )异氟醚降压组与非降压组间同一时间点血中S1 0 0B蛋白浓度无明显差异。降压组术后第 1天及第 2天血中S1 0 0B蛋白浓度均显著升高 (F =2 94 4 ,P =0 0 1 8)。结论　在颅内动脉瘤夹闭术中应用异氟醚控制性降压可能加重了术后脑损伤 ,不利于病人围麻醉期脑功能的保护     

尼卡地平控制性降压对局部脑氧饱和度的影响

目的观察颅内动脉瘤夹闭术中控制性降压对局部脑氧饱和度(rScO2)的影响。方法 15例ASAⅠ级的择期颅内动脉瘤夹闭手术患者,丙泊酚-瑞芬太尼全凭静脉麻醉,暴露动脉瘤期间静脉泵注尼卡地平0.5～1μg·kg-1·min-1,逐渐降低术前基础MAP的10%、20%和30%,夹闭动脉瘤后停止降压,观察降压过程中MAP、HR和rScO2的变化趋势。结果尼卡地平控制性降压过程中,随着MAP的逐渐下降,rScO2略有升高,T5时rScO2恢复至T1水平,各时点MAP、HR、PETCO2、BIS和rScO2差异均无统计学意义。结论颅内动脉瘤夹闭术中应用尼卡地平行控制性降压安全可行,不会影响脑氧供需平衡。     

地氟烷麻醉颅内动脉瘤夹闭术中收缩和舒张脑血管物质的变化

目的 观察地氟烷麻醉期间颅内动脉瘤病人行夹闭术中血管紧张素Ⅱ(AT-Ⅱ)、内皮素(ET)和降钙素基因相关肽(CGRP)的变化。方法 颅内动脉瘤拟行择期开颅动脉瘤夹闭术病人45例,麻醉诱导后气管插管控制呼吸,地氟烷维持麻醉(MAC1.0～1.5)。分别于麻醉诱导前(T_1)、剪硬膜(T_2)、夹闭动脉瘤(T_3)和动脉瘤夹闭后30min(T_4)4个时点采集动脉血,应用放免法检测血浆中AT-Ⅱ、ET和CGRP的浓度。结果 4个时点AT-Ⅱ均在正常值范围。ET于地氟烷麻醉中3个时点明显低于T_1(P<0.01)。麻醉中3个时点CGRP与T_1比较无统计学意义。结论 地氟烷麻醉下开颅动脉瘤夹闭术中缩血管物质降低,但舒血管物质不变,提示麻醉中应注重扩血管治疗,预防术中急性脑血管痉挛的发生。     

急性高容量血液稀释联合瑞芬太尼控制性降压对颅内动脉瘤术患者血流动力学和脑氧代谢的影响

目的 观察颅内动脉瘤夹闭术患者在急性高容量血液稀释(AHH)联合瑞芬太尼控制性降压(CH)后血流动力学和脑氧代谢的变化,评价其可行性.方法 选择颅内动脉瘤夹闭术患者40例,随机均分为硝酸甘油组(A组)和瑞芬太尼组(B组).手术开始时以15～20 ml·kg-1·h-1的速率输入4％琥珀酰明胶,使Hct稀释为25％～32％.在剪开硬脑膜后行CH,A组泵入硝酸甘油1～5 μg·kg-1 ·min-1;B组泵入瑞芬太尼12～30 μg·kg-1·h-1,使MAP维持在60～65 mm Hg,动脉瘤夹闭后10 min停止CH.记录两组患者AHH前(T0)、AHH后(T1)、降压前(T2)、降压后30 min(T3)、动脉瘤夹闭后5 min(T4)的MAP、HR、Hb和Hct,分别于T2～T4时采集颈内静脉球部血和桡动脉血作血气分析,检测动、静脉血氧饱和度(SaO2、SjvO2)、动、静脉血氧分压(PaO2、PjvO2)、Hb和Hct,计算动脉氧含量(CaO2)、颈内静脉氧含量(CjvO2)、动脉颈内静脉球部血氧差(Da-jvO2)、颈内静脉球部动脉乳酸差(VADL)和脑氧摄取率(CERO2).结果 与T0时比较,T1～T4时两组Hb和Hct均显著降低(P＜0.01).与T2时比较,T3、T4时两组MAP明显降低,A组HR明显增快,B组的HR明显减慢(P＜0.01);T3、T4时B组SjvO2和CjvO2明显高于T2时和A组,Da-jvO2和CERQ明显低于T2时和A组(P＜0.01).结论 AHH联合瑞芬太尼CH用于颅内动脉瘤夹闭术中,不但维持血流动力学的相对稳定,而且明显降低脑氧代谢率,较AHH联合硝酸甘油CH更具优越性.     

右美托咪定对腹腔镜前列腺癌根治术老年患者局部脑氧饱和度和术后认知功能的影响

目的观察右美托咪定对腹腔镜前列腺癌根治术老年患者对局部脑氧饱和度(rSO_2)和术后认知功能的影响。方法选择择期行腹腔镜前列腺癌根治手术的老年患者60例,年龄65~80岁,ASA分级Ⅰ~Ⅲ级,随机均分为两组:右美托咪定组(D组)在全麻诱导插管后泵注右美托咪定0.5μg/kg,10min泵注完毕,然后以0.5μg·kg~(-1)·h~(-1)的速度持续泵注至手术结束前30min,对照组(C组)泵入等量的生理盐水。术中使用FORE-SIGHT_脑氧饱和度监测仪监测rSO_2。记录入室时(T_0)、诱导插管后(T_1)、气腹后60min(T_2)和苏醒后(T_3)的rSO_2、MAP、PaCO_2和PaO_2。记录丙泊酚和瑞芬太尼的使用情况、术后躁动和恶心呕吐的发生情况。于术前1d、术后1d和3d使用蒙特利尔认知功能评分量表(MoCA)进行评分,记录患者术后认知功能障碍(POCD)发生情况。结果T_2时两组rSO_2、PaCO_2明显高于T_1时(P0.05)。D组患者丙泊酚和瑞芬太尼用量明显少于C组(P0.05)。D组MoCA评分明显高于C组(P0.05);D组2例(6.7%)患者发生POCD,明显低于C组的9例(30%)(P0.05)。结论右美托咪定用于老年患者腹腔镜前列腺癌根治手术对rSO_2未见明显影响,但可以减少POCD的发生。     

硝酸甘油联合瑞芬太尼在老年患者上颌骨切除术控制性降压中的应用

目的 比较硝酸甘油联合小剂量瑞芬太尼控制性降压与单纯硝酸甘油控制性降压在老年患者上颌骨切除术中的应用.方法 择期行上颌骨切除术的老年患者40例,随机均分为硝酸甘油联合瑞芬太尼组(NR组)和硝酸甘油组(N组),均采用全凭静脉麻醉.NR组采用硝酸甘油联合小剂量瑞芬太尼控制性降压,N组单纯硝酸甘油控制性降压.记录麻醉诱导前(T0)、达到降压目标时(T1)、达到降压目标后5 min(T2)以及停止降压后15 min时(T3)的HR、MAP,并记录达到降压目标的时间、输液量、出血量、硝酸甘油用量.结果 T1、T2时N组HR明显( )于T0时和NR组(P＜0.01); NR组达到降压目标的时间明显短于N组(P＜0.05);NR组硝酸甘油用量明显少于N组(P＜0.05).结论 在老年患者上颌骨切除术中,使用硝酸甘油联合小剂量瑞芬太尼行控制性降压安全、有效,对血流动力学影响小.     

沙滩椅位肩关节镜手术对高血压患者脑氧饱和度和术后认知功能的影响

目的观察沙滩椅位肩关节镜手术对高血压患者脑氧饱和度和术后认知功能的影响。方法将40例ASAⅠ～Ⅱ级肩关节镜手术患者分为两组,20例血压正常者为对照组,20例合并高血压者为实验组。监测麻醉诱导平稳后(为T_1)、沙滩椅位时(为T_2)、控制血压满足术者肩关节镜下手术操作需要后(为T_3)3个时点的颈静脉球静脉血氧饱和度(SjvO_2)和健侧肱动脉平均动脉压(MAP)。记录术前及术后24 h简易智能精神状态检查量表(MMSE)评分,评估患者术后认知功能变化。结果健侧肱动脉MAP对照组和实验组T_2、T_3均低于T_1(P0.05),T_2、T_3时点与T_1的差值(ΔT_2、ΔT_3)实验组高于对照组(P0.001)。SjvO_2对照组和实验组T_2、T_3时点均低于T_1(P0.05),并且T_2时实验组低于对照组(P0.001)。实验组3例出现了SjvO_2显著下降,分别为45%(T_3)、47%(T_2)和43%(T_3),其对应的健侧肱动脉MAP分别为8.4、9.1、8.7 kPa,及时调整血压后SjvO_2恢复到55%、58%和56%。MMSE评分两组术后24 h与术前比较以及两组之间比较差异均无统计学意义(P0.05)。结论沙滩椅位和控制性降压时高血压患者健侧肱动脉MAP和SjvO_2下降更显著,两组均未出现术后认知功能障碍。     

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.     

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.     

Immunomodulation in Transplantation with Photopheresis

Abstract: Photopheresis is a technique in which peripheral blood mononuclear cells, in the presence of a photoacti-vatable compound, are exposed extracorporeally to ultraviolet A light and reinfused, inducing a host autoregula-tory immune response. Experimental work and ongoing clinical studies are helping to define the role of this novel, safe, and non-toxic immunomodulating technology in the field of transplantation.