升主动脉瘤的外科治疗

目的探讨升主动脉瘤治疗经验。方法Marfan’s综合征12例，其中6例合并二尖瓣关闭不全。升主动脉夹层动脉瘤伴主动脉瓣关闭不全6例，升主动脉瘤合并主动脉瓣、二尖瓣关闭不全2例，单纯升主动脉瘤5例，行Bentall手术12例，Cabrol手术3例，Wheat手术5例；单纯升主动脉替换术5例。结果全组无手术死亡。结论Bentall手术是外科治疗升主动脉瘤的主要术式。早期诊断、早期手术是改善升主动脉瘤患者疗效的关键。     

胸主动脉瘤的外科治疗

目的总结19例胸主动脉瘤患者的外科治疗经验. 方法 19例胸主动脉瘤患者,其中升主动脉瘤9例(马方综合征8例),7例行Bentall 手术,2例行Cabrol手术;降主动脉瘤10例,均行降主动脉置换术. 结果除1例患者术中死亡外,其余患者经超声心动图检查均示主动脉瓣关闭良好,移植的冠状动脉、降主动脉通畅,无扭曲,无脊髓损伤和神经系统并发症.随访18例,随访时间0.3～5.4年,心功能恢复至Ⅱ级3例,Ⅰ级15例,效果满意. 结论手术治疗胸主动脉瘤安全有效.     

升主动脉瘤合并主动脉瓣关闭不全的外科治疗

目的总结21例升主动脉瘤合并主动脉瓣关闭不全的外科治疗经验。方法19例行Bentall手术,2例行Cabrol手术;5例同时置换二尖瓣。术前心功能IV级15例,III级6例。动脉瘤直径6～11 cm,平均(8.5±2.6) cm;17例主动脉内膜有撕裂,其中5例升主动脉远端仍有夹层。主动脉瓣环直径2.7～5.4 cm,平均(3.2±1.8）cm。超声心动图检查均示主动脉瓣严重关闭不全。结果手术后无早、晚期死亡,术后超声心动图和造影检查示主动脉瓣关闭良好,移植的冠状动脉通畅、无扭曲,效果满意。结论动脉瘤直径大于6 cm时应及时随访和做预防性手术,一旦发现夹层动脉瘤应立即手术,Bentall手术治疗升主动脉瘤效果良好。     

白塞氏病合并主动脉瓣置换术后瓣周漏的临床分析

目的总结白塞氏病所致主动脉瓣置换术后发生瓣周漏的外科治疗经验,探讨相关手术方式和解决方法。方法回顾性分析第二军医大学附属长海医院收治的4例白塞氏病所致主动脉瓣置换术后瓣周漏患者的临床资料,均为男性,年龄24~50岁(36±7岁)。其中3例为主动脉瓣重度关闭不全行主动脉瓣置换术后出现瓣周漏行改良Bentall手术,另1例为升主动脉瘤、主动脉瓣重度关闭不全行Wheat术后出现瓣周漏行改良Bentall手术。结果 4例患者术后恢复顺利,无并发症发生。均痊愈出院。术后随访1~24个月,心功能恢复至Ⅰ~Ⅱ级。3~6个月定期行超声心动图和全主动脉血管造影检查,未发现主动脉瓣周漏复发,人工机械瓣膜功能良好,人工主动脉血管通畅。结论白塞氏病合并主动脉瓣或升主动脉病变如单纯行心瓣膜置换术,术后人工瓣膜脱落的发生率较高,改良Bentall手术方式是解决问题的良好方法。     

升主动脉瘤合并主动脉瓣关闭不全外科手术后早期处理

目的总结升主动脉瘤合并主动脉瓣关闭不全患者手术后早期处理的经验。方法21例患者术前心功能(NYHA)Ⅳ级15例,Ⅲ级6例;施行Bentall手术19例,Cabrol手术2例。结果全组无早、晚期死亡,术后早期发生心律失常和出血等并发症2例。术后21例均行超声心动图检查,4例行逆行主动脉造影示主动脉瓣关闭良好,移植的带瓣管道通畅、无扭曲。随访0.5~11年,平均4.5年;无动脉瘤复发,效果满意。结论术前严格掌握手术适应证,升主动脉瘤直径大于6cm应及时随访和做预防性手术,一旦发现夹层动脉瘤应立即手术;术后及早发现、纠治心律失常和出血等并发症,早期用抗凝治疗,可提高手术成功率。     

升主动脉根部瘤的外科治疗

目的总结升主动脉根部瘤的外科治疗经验。方法101例升主动脉根部瘤患者（年龄14～72岁，平均年龄42．7岁）的主要病因为马方综合征（Marfan syndrome，58例），主动脉瓣环扩张症（34例），主动脉瓣二叶瓣畸形（5例），大动脉炎（4例）；术前有主动脉瓣关闭不全96例，主动脉瓣狭窄4例，术前合并有A型夹层26例，急性左心衰竭（5例）。手术类型：Wheat手术4例，传统或改良Cabrol手术13例，David手术1例，Bentall手术83例。同期行主动脉半弓置换术或降主动脉腔内支架植入术16例，全弓置换术或降主动脉腔内支架植入术4例，二尖瓣置换术或成形术14例，冠状动脉旁路移植术8例。结果全组手术死亡率为6．9％（7／101），2000年后降至3．6％（3／83）；术后主要并发症为低心排血量10例，呼吸功能不全9例，肾功能不全9例。术后随访94例，随访期间死亡1例，5例马方综合征患者术后出现B型夹层。结论Bentall手术是治疗升主动脉根部瘤的首选手术方法，术前左心功能及手术技术是影响手术效果的关键因素。     

A型主动脉夹层动脉瘤的外科治疗

目的　总结 1996年 1月至 2 0 0 2年 8月收治的 34例 A型主动脉夹层动脉瘤的外科治疗经验。　方法　应用 Bentall手术 19例 ,升主动脉人工血管置换术 7例 ,升主动脉人工血管置换加主动脉瓣成形术 (Trusler's法 )5例 ,分别行升主动脉人工血管置换及主动脉瓣置换术 (Wheat术 ) 2例 ,升主动脉、主动脉弓人工血管置换术 1例。结果　手术死亡 6例 ,死亡率 17.6 %。其中慢性主动脉夹层动脉瘤死亡 3例 ,急性夹层动脉瘤死亡 3例。随访 2 0例 ,随访率 71.4 %。随访时间 2～ 4 6个月 ,平均 2 4 .7个月 ,1例术后 3个月猝死 (原因不明 ) ,1例术后 6个月死于心内膜炎。18例存活患者情况良好。　结论　应根据夹层动脉瘤的部位及范围采用不同的手术方式 ,保留主动脉瓣的升主动脉人工血管置换术治疗该病效果较好 ,准确可靠的吻合技术、保留瘤壁的完整性 ,将使手术更为安全。     

主动脉瓣二叶畸形伴胸主动脉扩张的外科治疗

目的分析主动脉瓣二叶畸形伴胸主动脉扩张的临床特点及外科治疗。方法回顾性分析我院2010年1月至2014年6月行主动脉瓣二叶畸形伴胸主动脉扩张手术患者68例的临床资料,其中男47例、女21例,年龄26~77(44.5±16.3)岁。手术方式包括Wheat手术22例,主动脉瓣置换+升主动脉成形术10例,Bentall手术13例,主动脉瓣置换+升主动脉置换+右半弓置换术13例,Bentall手术+升主动脉置换+右半弓置换术8例,Bentall手术+升主动脉置换+全弓置换+支架象鼻术2例。结果 68例手术均顺利完成,住院死亡3例(死亡率4.4%)。神经精神系统并发症3例,肺部感染2例,二次开胸2例。术后随访63例,随访时间6个月至4年。术后2年死亡1例,其余患者生活质量良好,无再次手术。结论主动脉瓣二叶畸形合并胸主动脉扩张患者的临床特点多样,应根据患者的主动脉瓣及胸主动脉的病变特点选择合适的手术方式。     

正中切口解剖外旁路移植术一期治疗主动脉缩窄合并心脏畸形

目的总结正中切口解剖外旁路移植术一期治疗主动脉缩窄合并心脏畸形的外科治疗经验,以提高手术疗效。方法1997年7月至2008年7月,采用正中切口解剖外旁路移植术一期治疗主动脉缩窄合并心脏畸形31例,其中男20例,女11例;年龄31．9±11．7岁。合并的心脏畸形包括：主动脉瓣狭窄或关闭不全22例,二尖瓣狭窄或关闭不全9例,动脉导管未闭5例,升主动脉瘤4例,室间隔缺损3例,冠心病2例。解剖外旁路移植术包括升主动脉-腹主动脉旁路移植术22例,升主动脉-心包后降主动脉旁路移植术9例。同期手术包括主动脉瓣置换术16例,主动脉根部置换术6例,二尖瓣成形或置换术9例,升主动脉置换或成形术4例,动脉导管未闭缝合术5例,室间隔缺损修补术3例,冠状动脉旁路移植术2例。结果住院死亡1例（3．2％）,术后39d死于感染性中毒性休克。术后上、下肢收缩压压差较术前明显下降（13．7±10．2mmHg vs．64．2±25．3mmHg,P〈0．05）。随访27例,随访时间4～73个月,无晚期死亡、与人工血管相关的并发症和再次手术患者。结论正中切口解剖外旁路移植术是一期治疗成人及青少年主动脉缩窄合并心脏畸形的一种安全有效的手术方法。升主动脉腹主动脉旁路移植术及升主动脉-心包后降主动脉旁路移植术均可获得满意疗效。     

先天性主动脉瓣二叶化畸形的外科治疗

目的　探讨先天性主动脉瓣二叶化畸形的诊断、适宜手术时机、围术期处理以及手术疗效。　方法　 60例患者被施行心瓣膜置换术 ,行主动脉瓣机械瓣置换术 5 6例 ,行自体心包瓣置换术 4例 ;同时行主动脉窦瘤破裂修补术 2例 ,胸主动脉瘤修补术 2例 ,动脉导管未闭缝扎术 3例 ,室间隔缺损修补术 5例 ,冠状动脉旁路移植术 3例。其中伴感染性心内膜炎 2 5例。　结果　术后早期死亡 5例 ,死亡率为 8.3 %。随访 4 9例 ,平均随访时间 5 .4年 ,5年生存率为 84 .3 %。　结论　先天性主动脉瓣二叶化畸形以男性居多 ,左、右二叶型较前、后型常见 ,可致主动脉瓣关闭不全和 /或狭窄 ,以关闭不全多见 ( 75 % )。出现充血性心力衰竭、心绞痛、晕厥、感染性心内膜炎时应尽早行手术治疗 ,症状不明显的患者应定期复查超声心动图 ,主动脉瓣置换术是常用的手术方法。     

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.     

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.     

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.     

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.