电视胸腔镜辅助小切口Heller术治疗贲门失弛缓症

目的：探讨电视胸腔镜辅助小切口Heller术治疗贲门失弛缓症的临床效果。方法：回顾分析我院2000年6月～2006年5月16例贲门失弛缓症接受电视胸腔镜辅助小切口Heller术治疗的临床资料。手术经左第8肋间置胸腔镜，第7肋间后外侧切口6～8cm进胸，行食管肌层切开术。结果：16例均顺利完成手术，手术时间56～105min，平均64min，术后住院8～15d，平均11d。1例损伤食管黏膜术中修补，术后无严重并发症。16例随访2～24个月，平均14个月，15例吞咽困难消失，1例症状解除不完全，经食管扩张后症状消失，无胃食管反流症状。结论：电视胸腔镜辅助小切口Heller术，创伤小，恢复快，并发症少，住院时间短，合理掌握胃食管连接部的肌层切开范围，可有效防止术后胃食管反流。     

经腹腔镜改良Heller手术加胃底折叠术治疗贲门失弛缓症

目的:探讨腹腔镜治疗贲门失弛缓症的方法及其优势。方法:经腹腔镜行食管贲门括约肌切开术(改良Heller手术)加胃底折叠术治疗贲门失弛缓症1例。结果:手术顺利,手术时间140m in,术中出血量30m l。患者术后第3天进软食无异常后出院。术后3个月食管下括约肌(LES)残留压、松弛率以及食管基础压均恢复正常,钡餐结果显示为正常食管影像,24h食管pH值测定正常,未见返流。随访6个月,症状无反复。结论:经腹腔镜改良Heller手术加胃底折叠术治疗贲门失弛缓症具有创伤小,术后康复快,疗效确切等优点。     

电视胸腔镜食管下段肌层切开术(改良Heller术)治疗贲门失弛缓症(附21例报告)

目的探讨电视胸腔镜食管下段肌层切开术(改良Heller术)治疗贲门失弛缓症的可行性. 方法 1997年6月～2005年6月电视胸腔镜食管下段肌层切开术治疗贲门失弛缓症21例.采用双腔气管插管全麻,右侧卧位,经左胸,在4个胸腔镜trocar下进行操作.食管下段肌层切开长6～11 cm,胃壁肌层切开长0.5～1 cm,深及黏膜下.术中纤维食管镜辅助操作.均未行抗反流手术. 结果术中出血量50～100 ml,平均58 ml.手术时间60～270 min,平均137 min.3例术中发生食管黏膜破裂,2例镜下修补,1例中转开胸修补.全部患者术后恢复顺利,无严重并发症.术后随访1～80个月,2例分别于术后2、4个月吞咽困难复发,其余19例吞咽困难得到明显改善,吞咽困难改善程度优8例、良10例、中1例、差2例. 结论电视胸腔镜食管下段肌层切开术操作简单,创伤小,术后恢复快,疗效满意,可以作为贲门失弛缓症治疗的首选手术方法.     

腹腔镜改良Heller手术治疗贲门失弛缓症

目的:探讨腹腔镜改良Heller术治疗贲门失弛缓症的临床应用价值。方法:2004年2月至2008年4月我们为6例贲门失弛缓症患者行腹腔镜改良Heller术并随访。结果:手术时间45~122min,平均(74.0±29.0)min;术中出血5~65ml,平均(23.7±22.7)ml;无一例中转开腹及并发症发生;住院3~8d,平均(5.5±1.8)d。术后随访3~46个月,平均(26.8±16.2)月,5例症状缓解,1例轻度吞咽困难。结论:腹腔镜改良Heller手术具有术野清晰、并发症少、患者创伤小、康复快、住院时间短等优点,是治疗贲门失弛缓症首选方法之一。     

手术治疗贲门失弛缓症36例

目的 探讨贲门失弛缓症手术方法及效果。方法 回顾性分析36例贲门失弛缓症采用Heller＋Nissen手术治疗效果，男20例，女16例，平均年龄36岁，经胸手术32例，经腹手术4例，术中保护迷走神经，重建食管—胃His角和贲门功能，保护剥离食管黏膜创面。结果 36例无手术死亡，术后10天后均能进普食。随访5年，钡餐摄片，食管无狭窄，食管镜检查，2例食管下段轻度糜烂，余34例正常。结论 贲门失弛缓症行Heller＋Nissen手术效果好。     

腹腔镜Heller手术治疗贲门失弛缓症的初步临床经验

目的总结腹腔镜Heller手术治疗贲门失弛缓症的初步临床经验。方法2005年2～8月，对肺功能较差、合并肾功能不全或怀疑存在胸膜腔粘连的8例贲门失弛缓症行腹腔镜下Heller联合Dor胃底折叠手术，并进行随访。结果手术时间70～184min，平均103．8min；1例术中食管穿孔改开腹手术修补成功；术后住院3～10d，平均5．1d。术后随访1～6个月，平均3．8月，7例症状缓解，1例轻度吞咽困难。全组无手术死亡。结论腹腔镜具有刨伤小、术中暴露较佳、术后恢复快、术后住院时间短等优点，腹腔镜下Heller术可作为贲门失弛缓症的首选治疗方法，但是否附加胃底折叠术仍需进一步探讨。     

腹腔镜Heller括约肌切开术治疗贲门失弛缓症

目的：探讨采用腹腔镜微创手术治疗贲门失弛缓症的可行性及临床效果。方法：对5例患者在术中行胃镜定位、监视下行腹腔镜Heller括约肌切开术治疗。结果：4例手术顺利,1例患者由于粘连严重,术中分破远端食管,经胃镜证实后即行腹腔镜下修补术,术后1d,4例症状明显改善,1例术后1周吞咽困难症状逐渐改善。随访5～17个月,均未再发生吞咽困难、返流、胸骨后疼痛等症状。结论：腹腔镜Heller括约肌切开术治疗贲门失弛缓症创伤小、恢复快,并可作为内科治疗失败后的补救治疗。     

食管肌层切开术联合胃底折叠术治疗食管运动功能障碍性疾病的远期疗效

目的 比较食管肌层切开术加不同胃底折叠术式治疗贲门失弛缓症或弥漫性食管痉挛的远期效果.方法 1978年1月至1998年10月,共64例贲门失弛缓症或弥漫性食管痉挛患者经左胸行Heller手术+抗反流手术.其中21例加行Nissen全胃底折叠术(Nissen组),43例加行BelseyⅣ式部分胃底折叠术(Belsey组).患者于手术前后行影像学、食管核素排空、食管压力测定和内窥镜检查及24 h pH值监测.结果 全组无手术死亡及严重并发症.术后6年随访,Nissen组吞咽困难(P=0.025)及核素潴留(P=0.044)的发生率高于Belsey组.两种术式均可降低食管下括约肌的压力梯度.Nissen组术后食管直径较术前增加(P=0.012),而Belsey组增加不明显(P=0.695).两组烧心与反酸症状均少见.Nissen组有8例患者、Belsey组有1例患者因复发性吞咽困难需行二次手术(P＜0.01).结论 在治疗贲门失弛缓症或弥漫性食管痉挛患者时,加行全胃底折叠术可能并不适宜,而部分胃底折叠术可以提供满意的抗反流效果,且不会显著影响食管排空功能.     

贲门失弛缓症微创手术治疗体会

目的探讨贲门失弛缓症治疗的理想方法。方法总结12例贲门失弛缓症经胸小切口微创手术配合食管内水囊扩张的经验。结果治愈12例,术后反流性食管炎0例,无明显并发症。结论经胸微创手术加食管内水囊扩张术治疗贲门失弛缓症疗效确切、手术简单、创伤小、恢复快、不良反应小、近期疗效较好,值得推荐。但远期疗效仍需随访观察。     

经胸小切口食管肌层切开术治疗贲门失弛缓症

目的总结经胸小切口食管肌层切开术治疗贲门失弛缓症的临床经验. 方法 25例贲门失弛缓症患者中中度9例,重度16例 ,均接受了手术治疗.手术经左胸腋后线第7或第8肋间进胸,切口6～8cm,行食管肌层切开.全组均未行抗反流手术. 结果全部患者顺利完成手术,无死亡,平均手术时间50分钟,术后平均住院天数10天.1例患者因损伤食管黏膜,于术中予以修补,其余患者术后无并发症.随访全部患者,吞咽困难消失,无胃食管反流症状.8例术后行24小时食管pH监测无病理性反流. 结论经胸小切口行食管黏膜外肌层切开术,创伤小,恢复快,并发症少,住院时间短.合理掌握胃食管连接部的肌层切开范围可有效防止术后胃食管反流发生.     

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.     

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.     

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.