介入诊疗急性动脉性消化道大出血

目的探讨急性动脉性消化道大出血介入诊疗的临床应用价值。方法对39例急性动脉性消化道大出血患者行DSA检查,对38例出血征象阳性的患者中37例采用明胶海绵颗粒配合微弹簧圈进行介入栓塞治疗。结果 39例动脉造影中38例出血征象阳性,主要表现为对比剂外溢。接受栓塞治疗的37例中,止血成功36例(其中3例行第2次栓塞),均未发生与介入栓塞相关的严重并发症。最终2例患者转剖腹探查手术。结论介入技术是急性动脉性消化道大出血安全、有效的诊疗手段,能快速明确出血动脉及部位,并迅速有效控制出血。     

急诊介入栓塞治疗骨盆骨折小动脉损伤隐匿性出血

目的探讨急诊介入栓塞治疗骨盆骨折小动脉损伤隐匿性出血的临床价值。方法回顾性分析14例骨盆骨折小动脉损伤隐匿性出血患者的资料。14例均接受急诊介入栓塞止血,栓塞材料为明胶海绵颗粒、微弹簧圈。结果 14例动脉期造影均未见明显对比剂染色或积聚,延迟期共发现34条小动脉中远端表现为少量对比剂轻度染色或积聚,超选择性插管造影可见明显对比剂外溢。对34条出血小动脉均成功栓塞止血。术后2例患者因失血性休克、严重酸中毒及多脏器衰竭死亡。结论对骨盆骨折小动脉损伤隐匿性出血患者,超选择性介入栓塞是有效止血措施,延迟期造影有利于提高对小动脉损伤的检出率。     

外伤性肝脏出血的血管造影诊断和栓塞治疗

目的探讨外伤性肝脏出血的DSA诊断与介入栓塞治疗的临床应用价值。方法对18例肝脏外伤出血患者行急诊动脉DSA检查和介入栓塞止血治疗,栓塞材料采用明胶海绵和（或）聚乙烯醇（PVA）微粒。结果18例DSA检查出血表现为造影剂外溢,均获得了明确诊断。18例栓塞治疗后出血均立即停止,1例在治疗后24h内出血复发,遂行二次栓塞止血成功。随访3个月,无复发出血。未见严重并发症发生。结论DSA能及时、准确的发现肝脏出血的部位,是诊断外伤性肝脏出血的可靠方法。介入栓塞术治疗外伤性肝脏出血安全、迅速、有效,并能最大限度保护肝脏功能。     

急诊经导管动脉栓塞术治疗医源性肾动脉出血

目的探讨急诊经导管动脉栓塞术（TAE）治疗NN性肾动脉出血的疗效。方法对49例医源性肾动脉出血患者行急诊肾动脉造影,确定出血动脉后,以明胶海绵、PVA颗粒和弹簧圈进行栓塞。结果。肾动脉造影显示31例对比剂外溢,肾动静脉瘘7例,肾假性动脉瘤4例,假性动脉瘤破裂合并肾动静脉瘘5例,肾动脉一肾盏瘘2例。TAE后,所有患者出血完全停止,无严重并发症出现。术后随访12～16个月,均无再次出血。结论急诊TAE治疗医源性肾出血安全、有效,具有较高临床价值。     

MSCT在介入治疗泌尿系统医源性出血中的应用

目的探讨术前MSCT增强扫描对介入治疗泌尿系统不同部位医源性出血的价值。方法回顾性分析27例因泌尿系统不同部位医源性出血接受介入治疗患者的资料,比较术前MSCT增强扫描与术中首次DSA对出血责任血管的检出率,分析CT及DSA征象。结果 26例(26/27,96.30%)经术前MSCT增强扫描明确出血责任血管,主要表现为动脉期斑片状对比剂外溢、对比剂浓聚及肾静脉早期显影征象;1例未明确责任血管患者DSA可见动静脉瘘征象。24例(24/27,88.89%)经术中首次DSA明确出血责任血管,主要表现为对比剂外溢、假性动脉瘤及肾动静脉瘘;3例未明确责任血管患者术前MSCT增强扫描表现为对比剂外溢2例、肾静脉早期显影1例,术中参考术前增强MSCT表现调整后再次造影均明确责任血管。术前MSCT增强扫描与术中首次DSA对出血责任血管的检出率的差异无统计学意义(2χ=1.08,P=0.29)。结论介入治疗前MSCT增强扫描可较为准确地判定泌尿系统不同部位医源性出血责任血管,且对术中首次DSA无法明确出血责任血管患者可根据术前MSCT表现对DSA进行调整,从而快速、准确地进行栓塞。     

DSA和介入栓塞术在急性动脉性出血诊断与治疗中的应用

目的探讨数字减影血管造影和介入栓塞术对急性动脉性出血的诊断与治疗价值。方法急性出血患者22例，包括肝脏损伤出血4例，产后大出血7例，人流术后出血2例，大咯血6例，消化道出血3例。对出血部位行选择性DSA，明确诊断及出血动脉后在超选择插管基础上行栓塞治疗，栓塞材料为明胶海绵颗粒和／或聚乙烯醇颗粒。结果所有病例DSA均显示出血阳性征象，表现为造影剂外溢。22例栓塞治疗后出血均立即停止，随访3～24个月，1例大咯血患者在治疗后第4个月出血复发，遂行二次栓塞止血。未见严重并发症发生。结论DSA对诊断急性出血有较高的价值；介入栓塞术微创、并发症少，能迅速、安全、有效地控制出血，宜作为急性出血治疗的首先方法。     

急诊经导管动脉栓塞治疗医源性肝动脉出血

目的探讨医源性肝动脉出血的急诊肝动脉造影表现及经导管动脉栓塞(TAE)治疗的疗效。方法对38例医源性肝动脉出血患者行急诊肝动脉造影,确定出血动脉后,以明胶海绵、PVA颗粒和弹簧圈进行急诊栓塞治疗;对其急诊肝动脉造影表现及TAE疗效进行回顾性分析。结果 38例中,21例肝动脉造影可见对比剂外溢,5例肝动静脉瘘,9例肝动脉假性动脉瘤,3例肝动脉假性动脉瘤合并肝动静脉瘘。急诊TAE后38例出血均停止,总有效率为100%(38/38)。1例术后10天复发出血,再次栓塞治疗后出血停止。随访12个月,所有患者均无肝脏坏死及异位栓塞等严重并发症发生。结论急诊TAE治疗医源性肝动脉出血安全、有效。     

介入栓塞治疗上消化道大出血术后再出血的疗效评估

目的观察分析介入栓塞治疗上消化道大出血术后再出血的临床价值.方法选择!!例上消化道大出血术后再出血的患者,应用超选择性腹腔动脉造影确定出血部位,指导注入栓塞剂达到止血目的.结果!!例患者共行!'次选择性腹腔动脉造影及栓塞, !%例获得满意止血效果.结论选择性腹腔动脉造影结合介入栓塞止血,能够使上消化道大出血术后再出血患者得到及时的定位诊断和迅速、有效的治疗,是处理上消化道大出血术后再出血的重要方式.     

经导管肝动脉α-氰基丙烯酸正丁酯胶栓塞治疗肝内出血

目的探讨以α-氰基丙烯酸正丁酯胶(NBCA)作为栓塞剂经导管肝动脉栓塞治疗肝内出血的价值。方法收集接受经导管肝动脉栓塞治疗的肝动脉出血患者7例,均使用NBCA作为栓塞剂,评价技术成功率、临床有效率及相关并发症。结果造影显示假性动脉瘤6例,对比剂外溢1例。对7例患者均成功施行经导管肝动脉栓塞术,术后即刻造影假性动脉瘤和对比剂外溢征象消失,技术成功率100%;NBCA及超液化碘油混合剂用量为(0.76±0.24)ml;术后患者腹痛症状缓解,血红蛋白浓度升高,临床有效率100%。未发生手术相关并发症,随访1个月无再出血病例。结论采用NBCA胶行经导管肝动脉栓塞治疗肝内出血安全有效,具有重要临床应用价值。     

超选择性动脉栓塞对外伤性肝破裂假性动脉瘤的应用价值

目的探讨超选择性动脉栓塞对外伤性肝破裂假性动脉瘤的临床应用价值。方法对20例经MSCT扫描确诊为外伤性肝破裂假性动脉瘤的患者行介入栓塞治疗,栓塞材料采用COOK弹簧圈。术后第3天、第1个月及第3个月复查MSCT及肝功能。结果 20例MSCT检查发现肝破裂假性动脉瘤,DSA检查表现为肝内动脉瘤样扩张并见对比剂外溢征象。20例栓塞治疗后出血均立即停止,瘤样扩张的血管消失。随访3个月,无复发出血,未见严重并发症。肝功能介入治疗前与术后第3天对比无明显改变,且经保肝治疗后肝功能于术后第1个月均恢复正常。结论超选择插管介入治疗外伤性肝破裂假性动脉瘤安全、迅速、有效,并能最大限度保护肝脏功能。     

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 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.     

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.     

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.     

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.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.