术中支架象鼻技术治疗Stanford B型主动脉夹层

目的 总结术中支架象鼻技术治疗Stanford B型主动脉夹层的临床效果和经验.方法 2009年3月至2011年12月,24例锚定区不足或左锁骨下动脉受累及合并升主动脉或心脏病变的Stanford B型主动脉夹层的患者在北京安贞医院接受手术.其中男20例,女4例,年龄(50.6±9.8)岁.合并高血压20例,主动脉瓣关闭不全2例,主动脉根部瘤1例,二尖瓣关闭不全1例,主动脉缩窄1例.14例有吸烟史.4例为胸降主动脉覆膜支架术后内漏.结果 24例患者均行直视下支架象鼻术,同期左锁骨下动脉左颈总动脉转流5例,主动脉瓣替换+升主动脉成形3例,左锁骨下动脉重建2例,二尖瓣和主动脉瓣置换1例,升主动脉降主动脉人工血管转流1例.体外循环(163.1±48.6) min,低流量选择性脑灌时间(29.1 ±12.4) min.无围手术期死亡.二次开胸止血1例;呼吸功能不全气管切开1例;无截瘫及卒中发生.无住院死亡,并发症发生率8.3％(2/24例).1例失访;随访23例,随防率95.8％(23/24),平均随访24个月,随访期间2例因Ⅰ型内漏行修补术,1例因支架远端假性动脉瘤行主动脉覆膜支架修复.20例(86.4％)患者支架附近可见血栓形成.结论 对锚定区不足或左锁骨下动脉受累及合并升主动脉或心脏病变的Stanford B型主动脉夹层患者行直视下支架象鼻手术是一种有效的外科治疗手段,可以获得满意的临床效果.远期结果需进一步随访.     

孙氏手术治疗升主动脉替换术后残余主动脉夹层

目的 探讨Stanford A型主动脉夹层近端主动脉替换术后残余主动脉夹层的手术时机和手术方式.方法 2009年3月至2011年11月,连续收治16例Stanford A型主动脉夹层术后残余夹层的患者,男13例,女3例;年龄23 ～ 61岁,平均44岁.其中8例为马方综合征.中低温停循环、低流量顺行脑灌注下行孙氏手术(主动脉弓替换+支架象鼻术).其中单纯行孙氏手术12例;同期行主动脉根部替换术(Bentall手术)3例,主动脉根部替换术+冠状动脉旁路移植术(Bentall+ CABG)1例,冠状动脉吻合口漏修补术1例,二尖瓣置换术(MVR)1例.结果 再次手术距离首次手术时间(66±40)个月.体外循环(193±49)min,心肌阻断(90±28) min,选择性脑灌注(22±10) min.术后气管插管(17±10)h.无住院死亡.术后并发症4例,其中左下肢轻瘫1例随访期间好转;开胸止血、乳糜胸和胸骨后感染各1例,均于治疗后痊愈出院.患者出院前均行主动脉CT血管造影检查,示人工血管血流通畅,降主动脉真腔较术前明显扩大,支架段假腔血栓形成.随访3～42个月,平均17个月.1例术后3个月因远端夹层破裂死亡,1例术后6个月行全胸腹主动脉替换术,1例因胸降主动脉扩张合并内膜残余破口行胸主动脉腔内修复术.结论 Stanford A型主动脉夹层升主动脉替换术后残余夹层的患者,当主动脉弓扩张速度超过0.5 cm/年,或直径扩张至5 cm以上(或扩张至4.5 cm但合并弓部破口或马方综合征)时,应再次接受手术治疗,孙氏手术治疗安全有效,手术死亡及相关并发症发生率较低,近期结果良好.     

马方综合征主动脉根部手术后远端主动脉病变再次外科治疗

目的 总结马方综合征主动脉根部手术后远端主动脉病变的再次外科治疗结果,探讨相关治疗策略。方法 2000年1月至2010年1月,28例马方综合征主动脉根部手术后远端主动脉病变患者进行再次手术治疗。其中男20例,女8例;年龄23～52岁,平均(38.5±8.7)岁。首次手术包括Bentall手术24例,David手术4例。Stanford A型夹层8例,主动脉根部瘤20例。再次手术包括：胸腹主动脉置换术10例,全主动脉弓置换及支架象鼻术7例,胸降主动脉置换术6例,全主动脉置换术2例,全主动脉弓置换术2例,部分主动脉弓置换术1例。两次手术间隔1 ～12年,平均(6.43 ±3.07)年。结果 术后发生神经系统并发症4例(17％),包括脑卒中1例,截瘫1例,单侧下肢一过性运动障碍2例。二次开胸止血3例,急性肾功能衰竭接受血滤治疗1例。3例因术后呼吸机辅助时间延迟接受气管切开术。术后全部随访,随访时间10～ 118个月,平均(40.8±29.5)个月。住院死亡2例(7.1％),术后1年、5年实际生存率分别为(94.5±1.3)％、(90.6±1.4)％。结论 马方综合征行主动脉根部手术后因远端主动脉病变再次外科治疗临床结果满意。对于患主动脉A型夹层的马方综合征,首次手术即采用积极的主动脉全弓置换及象鼻手术更好。     

不同手术方式治疗急性StanfordA型主动脉夹层——单中心5年临床经验

目的 总结不同手术方式治疗急性Stanford A型主动脉夹层的临床经验。 方法 回顾性分析2008年1月至2012年11月于中国医科大学附属第一医院因急性Stanford A型主动脉夹层而实施外科治疗的197例患者的临床资料。男131例、女66例,年龄 （51.2±13.9） 岁。所有患者经磁共振成像 （MRI） 或主动脉CT血管造影（CTA）确诊。根据主动脉根部病变情况,进行单纯升主动脉置换、Bentall、Wheat、Cabrol或David手术。主动脉弓部进行全主动脉弓置换、半弓置换或简化全主动脉弓置换＋降主动脉支架象鼻手术。 结果 近端单纯升主动脉置换113例（57.4%）,Bentall手术67例（34.0%）,Wheat手术13例（6.6%）,Cabrol手术1例（0.5%）,David手术3例（1.5%）。全主动脉弓置换＋降主动脉支架象鼻手术82例（41.6%）,半弓置换＋降主动脉支架象鼻手术77例（39.1%）,简化全主动脉弓置换＋降主动脉支架象鼻手术41例（20.8%）。二次开胸止血1例（0.5%）,无永久性神经系统并发症发生,手术30 d死亡率为4.1%（8/197）;随访时间3～52（15.9±11.4）个月,随访率65.0%;1例马方综合征患者术后8个月死于腹主动脉瘤破裂。 结论 根据病变情况,选择适当的外科治疗策略,急性Stanford A型主动脉夹层外科治疗效果满意。     

主动脉瓣置换术后患者再次主动脉外科干预47例

目的 回顾性分析47例主动脉瓣术后再次主动脉外科治疗病例,提高对主动脉瓣术后主动脉疾病再治疗的认识.方法 2003年1月至2012年6月,47例患者因主动脉瓣术后接受再次主动脉手术治疗.男38例,女9例,再次手术间隔时间(6.0±3.8)年.行主动脉根部替换14例,升主动脉替换10例,主动脉根部/升主动脉+全弓替换+象鼻支架置入术21例,全胸腹主动脉替换2例.所有出院患者均行门诊复查和电话随访.结果 47例患者中主动脉夹层25例(53％),升主动脉瘤12例(26％),主动脉根部瘤10例(21％).风湿性心脏病患者升主动脉直径年增长值高于马方综合征患者(P＜0.05).47例均接受外科手术治疗,术中死亡1例;余患者均出院并随访,随访时间(53.49±33.79)个月,3年生存率83％.结论 对马方综合征、风湿性心脏病等主动脉瓣疾病合并主动脉病变要积极干预、严格随访,减少术后主动脉不良事件.     

主动脉夹层的细化分型及其应用

目的探讨在Stanford分型的基础上根据主动脉夹层的部位和病变程度再进行细化分型,对指导临床选择手术时机、确定治疗方案和手术方式,以及判断预后的价值。方法1994年1月至2004年12月我院治疗主动脉夹层708例。其中Stanford A型夹层477例：（1）根据主动脉根部病变程度分为3型。A1型（主动脉窦部正常型）212例,行保留主动脉窦部的主动脉替换;A2型（主动脉窦部轻度受累型）72例,行主动脉窦部成形63例、David手术9例;A3型（主动脉窦部重度受累型）193例,行主动脉根部替换术（Bentall手术）。（2）根据主动脉弓部病变分为2型。C型（复杂型）78例,行主动脉弓部替换＋象鼻术;S型（单纯型）399例,行部分主动脉弓部替换。Stanford B型夹层231例,（1）根据主动脉扩张的范围分为3型：B1型：降主动脉无扩张或仅有近端扩张,147例,行腔内带膜支架主动脉腔内修复术103例（B1S型）、部分胸降主动脉替换术32例、部分胸降主动脉替换术＋远端支架象鼻术12例;B2型：全部胸降主动脉扩张,53例,行部分胸降主动脉替换术＋主动脉成形32例、全部胸降主动脉替换术21例;B3型：全部胸降主动脉及腹主动脉扩张,31例行胸腹主动脉替换术。（2）根据左锁骨下动脉和远端主动脉弓部是否受夹层累及分为2型：C型（复杂型）：夹层累及左锁骨下动脉或远端的主动脉弓部,44例,在深低温停循环下手术治疗;S型（单纯型）：远端主动脉弓部和左锁骨下动脉未受夹层累及,187例,介入治疗103例、手术治疗84例（常温阻断下手术60例,股动脉-股静脉转流下手术24例）。结果Stanford A型夹层住院病死率为4．6％（22／477）,并发症发生率为14．5％（69／477）。Stanford B型夹层：介入治疗组病死率1．9％（2／103）,并发症发生率为2．9％（3／103）,轻度内漏发生率为9．7％（10／103）;手术治疗组住院病死率为3．1％（4／128）,并发症发生率为18．8％（24／128）。结论细化主动脉夹层的分型对于术前判断手术时机、制定手术方案和初步判断预后,具有重要的指导作用。     

改良全主动脉弓置换治疗老年Stanford A型主动脉夹层

目的总结改良全主动脉弓置换治疗老年Stanford A型主动脉夹层的临床经验,并探讨其疗效。方法 39例老年Stanford A型主动脉夹层患者在深低温停循环、双侧顺行脑灌注下行外科手术。根部处理根据不同病变情况,选择不同术式,包括单纯升主动脉置换、Bentall、Wheat手术。主动脉弓部采用四分支血管行全主动脉弓置换,降主动脉内置入硬象鼻支架,并行支架开窗,完成左锁骨下动脉重建。结果全组平均体外循环时间为(180.49±30.46)min,平均停循环时间(27.22±10.58)min,平均脑灌注时间(32.42±12.36)min,平均心肌阻断时间(94.84±24.83)min。升主动脉置换17例,Wheat手术10例,Bentall手术12例。全组无术中死亡,术后住院死亡2例,脑梗塞1例,短暂性神经功能障碍3例,行肾脏透析治疗3例。全组无出血再次开胸、声音嘶哑、左上肢感觉运动功能障碍等情况。术后复查主动脉CTA弓部分支血管血流通畅,象鼻支架无内漏。无术后死亡及二次手术者。结论选择合适的手术时机及手术方式,老年Stanford A型主动脉夹层患者仍能获得满意的外科手术效果。     

60岁以上老年Stanford A型主动脉夹层手术31例体会

目的 总结老年Stanford A型主动脉夹层外科治疗经验.方法 31例60岁以上老年A型主动脉夹层患者,均在深低温停循环、低流量脑灌注下手术.改良Wheat +全弓置换+支架象鼻术1例,Wheat手术2例,David术+全弓置换+支架象鼻术3例,Bentall+全弓置换+支架象鼻术9例,其中1例同期行心包剥脱术,升主动脉+全弓置换+支架象鼻术16例,其中合并冠状动脉旁路移植术4例.结果 体外循环时间(221±43)min,主动脉阻断时间(132±41)min,停循环时间(47±12)min.术后发生一过性脑功能紊乱4例,经积极处理后均痊愈出院;肾功能衰竭3例,1例经床边血液透析治疗好转,2例放弃治疗;切口愈合不良2例;术后近期死亡2例,其中1例系院外夹层破裂急诊入院手术,死于失血性休克,1例死于多脏器功能衰竭;二次开胸止血1例.术后复查CT显示,升主动脉及弓部人工血管血流通畅,支架位置良好,无内漏.随访2～35个月,术后近期1例因抗凝意外死亡,无再次手术者.结论 对老年A型主动脉夹层患者,手术治疗安全、有效.术中根据病情采取恰当的外科处理,围术期及时发现并处理各种并发症,可以获得良好治疗效果.     

急性复杂型Stanford A型主动脉夹层的外科治疗

目的：评价急性复杂型Stanford A 型主动脉夹层手术中改良双侧选择性顺行脑保护的效果及升主动脉插管、左锁骨下动脉（LSA）“开窗”技术对手术风险的影响。方法122例急性复杂型Stanford A 型主动脉夹层患者行改良全主动脉弓置换加降主动脉内支架象鼻植入术,按照脑保护及动脉供血管插管方式分为单侧脑保护组与改良双侧脑保护组及右锁骨下动脉（RSA）插管组与主动脉插管组,比较各组的手术方式、死亡率及并发症率。部分患者采用左锁骨下动脉“开窗”技术重建血运。结果单侧脑保护组与改良双侧脑保护组总的院内死亡率分别为5．77％、2．86％,差异无统计学意义（P值为0．650）;神经系统总并发症率分别为26．92％、10．00％,差异有统计学意义（P值为0．014）。右锁骨下动脉插管组与升主动脉插管组总的院内死亡率均为4．55％,总并发症率分别为15．9％、15．2％,差异均无统计学意义（P值分别为1、0．914）。左锁骨下动脉“开窗”者术后多次复查CTA左锁骨下动脉均通畅,无左锁骨下盗血综合征发生,1例出现无需处理的少量内漏。结论改良双侧选择性顺行脑保护安全、可行、可靠;选择升主动脉插管符合生理、操作简捷,不增加手术风险;左锁骨下动脉“开窗术”简化了手术,缩短了深低温停循环时间,增加了手术安全性。     

头臂血管转流并主动脉覆膜支架植入术在Stanford B1C型主动脉夹层中的应用

目的评价头臂血管转流并主动脉覆膜支架植入术治疗Stanford B1C型主动脉夹层的治疗效果。方法 2013年12月至2017年12月期间我中心应用头臂血管转流并同期行覆膜支架植入手术技术治疗Stanford B1C型主动脉夹层患者49例,其中男33例、女16例,平均年龄(60.4±5.5)岁。29例行左颈总动脉-左锁骨下动脉人工血管转流术,18例行右颈总动脉-左颈总动脉-左锁骨下动脉人工血管转流术,2例行右颈总动脉-右锁骨下动脉转流+左颈总动脉-左锁骨下动脉人工血管转流术。结果全组患者术后30 d内死亡1例(2.0%),术后生存48例,随访率100.0%(48/48),术后随访6～47(26.8±11.9)个月,其中1例术后6个月再发胸痛,急诊复查全程主动脉血管造影CT提示逆撕Stanford A1S型夹层,行外科手术,效果满意。全组存活患者未发生内漏。结论头臂血管转流并同期行主动脉覆膜支架植入手术治疗Stanford B1C型主动脉夹层患者是安全有效的。     

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.