控制性降压联合自体血回输在脊柱手术中的应用

目的 探讨控制性降压联合自体血回输技术应用于复杂脊柱外科大手术的临床效果及安全性. 方法 将40例脊柱外科大手术的患者用抽签法随机分为两组(每组20例):控制性降压联合自体血回输组(A组)和非自体血回输组(B组).A组全麻诱导后,术中用硝酸甘油行控制性降压,维持平均动脉压(mean arterial pressure,MAP)(65±5) mmHg(1mmHg=0.133 kPa),并用血液回输仪回收术野出血;B组未行自体血回输;两组术中血细胞比容(hematocrit,Hct)低于25％即输库血.两组术中连续监测心率(heart rate,HR)、MAP、心电图(electrocardiogram,ECG)和中心静脉压(central venous pressure,CVP).记录两组患者术中出血量、异体输血量及输血相关并发症,术前和术后24 h红细胞(red blood cell,RBC)、血红蛋白(hemoglobin,Hb)、Hct、血小板(platelet,PLT)及凝血酶原时间(prothrombintime,PT)、活化部分凝血酶原时间(activeated partial thromboplasting time,APTT)和纤维蛋白原(fibrinogen,FG). 结果 A组出血量(1 120±510) ml与B组(1 524±457) ml比较,差异有统计学意义(P＜0.05);A组输异体血发生率(10％)显著少于B组(100％)(P＜0.01);术后24 h两组患者RBC、Hb、Hct、PLT、PT、APTT和FG与术前比较差异有统计学意义(P＜0.05),但都在正常范围内,两组间比较差异无统计学意义(P＞0.05);两组均无肺水肿、心力衰竭及创面异常出血并发症. 结论 控制性降压复合术中自体血回输在复杂脊柱手术中的应用是安全可靠的,能明显减少出血量,减少甚至避免异体血输入.     

自体血回输在腰椎滑脱症手术中应用的前瞻性研究

[目的]比较腰椎滑脱症患者术中应用与不应用自体血回输后总失血量、血红蛋白(Hb)、红细胞压积(HCT)变化以及异体输血情况。[方法]本研究为前瞻性随机对照试验,40例腰椎滑脱手术治疗患者随机分为自体血回输组(A组),不自体血回输组(B组)。自体血回输组自手术开始同步收集术中出血,清洗过滤后术中或术后2 h内完全回输。将两组患者术前与术后(第1、3、5、7 d)的Hb、HCT、总失血量、异体血使用量及使用率进行对比分析。[结果]两组患者的年龄、体重、性别比无统计学差异。A组回输自体血的容量平均为(319.22±161.57)ml。两组术前的Hb(P=0.480)及HCT(P=0.271)值均无统计学差异(P>0.05),但术后A组上述两指标值均>B组(P>0.05)。术后两组Hb及HCT均逐渐下降,术后第3 d最低,术后第5、7 d均呈增长趋势。术前分别与术后1、3、5、7 d的血红蛋白及红细胞压积的差值相比较,A组均相似文献   

川芎嗪对自体血回输患者围术期体液免疫功能的影响

目的 探讨川芎嗪对自体血回输患者围术期体液免疫功能的影响.方法 择期行脊柱手术患者60例,年龄20～60岁,体重50 ～ 75 kg,ASA分级Ⅰ或Ⅱ级,采用随机数字表法,将患者随机分成2组(n=30),试验组:于收集自体血前30 min,经5 min静脉输注川芎嗪2mg/kg,并在回收血液的肝素盐水和洗涤盐水内加入川芎嗪,每500 ml加入川芎嗪25 mg;对照组不给予川芎嗪.于麻醉诱导前(T0)、术后1 h(T1)、1 d(T2)及5 d(T3)时取静脉血样,采用ELISA法测定血清免疫球蛋白(IgG、IgM)的浓度;记录手术时间、术中出血量、回输血量.结果 两组患者手术时间、术中出血量、回输血量比较差异无统计学意义(P＞ 0.05).与T0时比较,对照组T1～T3时血清IgG和IgM浓度降低,试验组T1、T2时血清IgG浓度降低(P＜0.05或0.01),T3时差异无统计学意义,T1～T3时血清IgM浓度差异无统计学意义(P＞0.05);与对照组比较,试验组T2、T3时血清IgG浓度、T1～T3时血清IgM浓度升高(P ＜0.05或0.01).结论 川芎嗪可在一定程度上减轻自体血回输患者体液免疫抑制,改善体液免疫平衡状态.     

输注自体血与库存血对患者术后炎症反应的影响

目的探讨输注自体回输血与保存时间短于2周的库存血对患者术后炎症反应的影响。方法选择择期行腰椎滑脱椎弓根内固定植骨融合术手术,估计出血量多于500ml的骨科患者40例。其中20例患者应用自体血回输装置即为回收血组(A组),20例患者单独输注短于2周的库存血即为库存血组(B组)。检测两组患者Hb、Hct、pH、K+、ATP含量和2,3-二磷酸甘油酸(2,3-DPG)及输血后患者的WBC、C-反应蛋白(CRP)、血沉(ESR)。结果 A组患者的pH值、K+、Hct、ATP、2,3-DPG均明显高于B组(P0.05);两组术后1、3dWBC,术后1、3、5dCRP、ESR均明显高于术前(P0.05);术后1、3、5dB组的CRP、ESR均明显高于A组(P0.05)。结论自体血的质量明显优于库存血,输注自体血的患者术后CRP、ESR明显低于输注库存血的患者,提示输注自体血的炎症反应发生率较库存血低。     

术前自体血小板分离回输在非体外循环下冠状动脉旁路移植术中的应用

目的 探讨术前自体血小板分离回输在非CPB下冠状动脉旁路移植术(off-pump coronary artery bypass grafting,OPCABG)中应用的临床效果. 方法 32例OPCABG患者采用随机数字表法分为两组(每组16例):对照组(A组)行术中自体血回输,急性血小板分离组(B组)行急性等容血液稀释(acute normovoemic hemodiltion,ANH)联合自体富血小板血浆(platelet-rich plasma,PRP)回输及术中自体血回输.于麻醉诱导前(T0)、肝素化前(T1)、术后1 h(T2)、术后24 h(T3)各时间点记录有关凝血功能的各项指标.记录T2、T3时点引流液. 结果 B组急性血小板处理的全血容量为(1 100±145) ml,采集PRP(166±30) ml,血小板计数(platelet count,Plt)(1 010±210)×109/L,占全身Plt总数(26±3)％.与A组比较,B组T2时点Plt升高明显,T2、T3时点引流液降低、异体红细胞输注率降低(P＜0.05),凝血功能指标差异无统计学意(P＞0.05). 结论 术前自体血小板分离回输在OPCABG中可减少异体血输注量,减少输血费用,降低术后出血量,避免血液传播性疾病及输血反应的发生.     

二氧化碳气腹手术回收自体血的临床价值

目的探讨CO2气腹在腹腔镜手术中对术野回收自体血携氧功能和电解质的影响,评价其临床应用价值,为日后腹腔镜手术中自体血回收、回输提供参考性依据。方法选取2016年5月至2017年8月择期行CO2气腹手术(CP组,腹腔镜肝血管瘤手术)和非CO2气腹手术(NCP组,脊柱手术)的患者各20例,男18例,女22例,年龄27~79岁,BMI 21.64~24.46 kg/m2,ASAⅠ或Ⅱ级。两组患者均采用全身麻醉,术中监测HR、NBP、IBP、Sp O2、ECG、PETCO2、CVP、BIS和T,应用自体血液回收机进行术野血回收、回输。分别检测两组患者储血器过滤前1 min(过滤前1 min)、储血器过滤后1 min(过滤后1 min)、回输洗涤血前10 min(回输前10 min)和回输洗涤血后10 min(回输后10 min)各血样的p H、PCO2、PO2、SO2、Hct、Hb、Lac和Na+、K+、Ca2+、Cl-、Mg2+等电解质浓度,并记录患者手术时间、血液离体时间、出血总量、回收和回输血液总量。结果与过滤前1 min和过滤后1 min比较,CP组回输前10 min和回输后10 min p H、PO2、SO2明显升高(P0.05);NCP组回输前10 min和回输后10 min p H明显降低(P0.05),PCO2和PO2明显升高(P0.05)。与NCP组比较,CP组过滤前1 min和过滤后1 min p H、PO2和SO2明显降低,PCO2明显升高(P0.05);与过滤后1 min比较,CP组过滤前1 min、回输前10 min和回输后10 min Na+和Cl-浓度明显降低,K+、Ca2+和Mg2+浓度明显升高(P0.05);NCP组回输前10 min和回输后10 min Na+和Cl-浓度明显降低,K+、Ca2+和Mg2+浓度明显升高(P0.05)。各时点两组电解质指标差异均无统计学意义。结论 CO2气腹手术回收自体血过酸,携氧较低,回输后改变患者酸碱平衡,增加酸中毒风险,临床应用价值有待进一步探讨。     

脑血管手术机械通气患者灌注变异指数与CVP和MAP的相关性研究

目的 研究脑血管手术机械通气患者灌注变异指数(PVI)与CVP和MAP的相关性.方法 脑血管手术患者15例,术中均需自体血回输,术前30 min内输注6%羟乙基淀粉130/0.4( HES)500 ml,术中输注复方氯化钠10ml·kg-1·h-1.机械通气采用容量控制模式,潮气量8 ml/kg,保持气道压在18 cm H2O左右.记录诱导前(T0)、诱导后(T1)、输注HES后(T2)、自体血回输前(T3)、自体血回输后(T4)的PVI、CVP和MAP.结果 PVI的变化与CVP、MAP的变化呈负相关,相关系数分别为-0.82(P＜0.05)和-0.73(P＜0.05).结论 PVI可以作为脑血管手术机械通气患者血流动力学变化的有效判断指标,其与CVP和MAP呈负相关.     

术中自体血回输在脊柱外科手术中的应用及其并发症

目的 探讨术中自体血回输在脊柱外科手术中的应用及并发症.方法 应用国产自体-3000P型血液回输机对115例脊柱手术术中失血进行回输.结果 115例脊柱外科手术回输浓缩红细胞75 900 ml,平均每人术中出血(1250±862)ml,回输自体血(670±445)ml,异体输血(520±212)ml.除1例并发凝血功能障碍外,无输血及免疫调节反应,无术后感染.结论 术中自体血回输能减少脊柱手术异体血用量,并发症少,使用安全有效.     

全膝关节置换术后不同引流方式的临床对比研究

目的 探讨人工全膝关节置换术后不同引流方式对临床疗效的影响.方法 将2010年10月至2012年11月55例接受单侧初次人工全膝关节置换患者分为三组:引流自体血回输组25例、延迟开放引流组12例、常规引流组18例.各组采用相同的手术技术和术后处理,比较术后总引流量(包括术中开放止血带止血时的出血量),异体血输血情况,术后第1、3、7天体温,手术前后血红蛋白值,肢体肿胀情况,伤口愈合质量和术后关节功能.结果 引流自体血回输组平均引流量为(799.2±196.7) ml,明显多于其他两组;延迟开放引流组平均引流量为(381.7±129.2) ml,明显少于常规引流组(666.1±155.0) ml.常规引流组术后第1天血红蛋白平均为(81.33±9.86) g/L,引流自体血回输组平均为(91.96±9.57)g/L和延迟开放引流组平均为(91.50±7.92) g/L,较常规引流组明显升高,差异有统计学意义;而引流自体血回输组与常规引流组的差异无统计学意义.常规引流组有8例患者(44.4％)术后接受异体血输注,明显多于引流自体血回输组(4例,16.0％)和延迟开放引流组(2例,16.7％),差异有统计学意义;引流自体血回输组与常规引流组的差异无统计学意义.引流自体血回输组术后第1、3、7天最高体温明显增高,与其他两组的差异有统计学意义.术后肢体肿胀、伤口愈合质量和术后关节功能三组的差异无统计学意义.结论 延迟开放引流可以减少术后显性失血,降低异体血输注率,与自体引流血回输相比,降低术后发热和额外费用,带来更大的临床收益,值得进一步探讨和应用.     

关节置换术中输注异体血和自体血回输对术后血液流变学指标的影响

目的比较关节置换术中输注异体血和自体血回输对术后血液流变学指标的影响。方法随机将95例行关节置换术并术中输血的患者分为2组。异体组术中输注异体血,自体组术中行自体血回输。比较两种输血方法对患者术后血液流变学指标的影响。结果异体组术中平均输血量明显少于异体组,差异有统计学意义(P<0.05)。虽然术后第1天自体组的红细胞压积明显低于异体组,差异有统计学意义(P<0.05),但2组其他血液流变学指标及术后第3、7天的血液流变学指标的差异均无统计学意义(P>0.05)。结论自体血回输能有效减少术中输血量,而且不影响术后的血液流变学指标。是解决术中血液丢失的安全有效的方法。     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

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.