新辅助治疗联合盆腔脏器切除术治疗复发直肠癌

目的探讨新辅助治疗联合盆腔脏器切除术对复发直肠癌的临床治疗价值。方法对35例复发直肠癌患者,采用新辅助治疗方案。常规分次放疗,放疗总剂量(DT)46Gy,每周5次,每次2Gy。全身化疗2个疗程,每次予以奥沙利铂130mg/m2,第1天静脉点滴;甲酰四氢叶酸钙(CF)200mg/m2,第1~3天静脉点滴;氟脲嘧啶(5-Fu)500mg/m2,第1~3天静脉点滴。治疗结束后4~6周进行盆腔脏器切除手术。结果经新辅助治疗后,病理完全缓解6例,肿瘤平均缩小38.4%,65.7%的病例T期下降。全组无手术死亡,R0切除率为88.5%,手术并发症发生率为13.3%。本组总的3年生存率为82.8%;5年生存率为48.5%;其中获得R0切除的患者,3年生存率为90.3%,5年生存率为54.6%。结论新辅助治疗联合盆腔脏器切除术是治疗复发直肠癌的有效方法。通过降低肿瘤病期,提高手术切除率,从而提高患者生存率。     

新辅助治疗低位局部进展期直肠癌35例结果分析

目的 探讨新辅助治疗对低位局部进展期直肠癌的临床治疗价值。方法 对35例低位局部进展期直肠癌患者，采用新辅助治疗方案。常规分割放疗，放疗总剂量DT：46Gy，每次2Gy，每周5次。全身化疗2个疗程，每次予以奥沙利铂130mg／m^2，第1天静脉点滴；甲酰四氢叶酸钙(CF)200mg／m^3，第1～3天静脉点滴；氟尿嘧啶(5-FU)500mg／m^2，第1～3天静脉点滴。治疗结束后4～6周进行手术。结果 经新辅助治疗后，病理完全缓解7例，肿瘤平均缩小34．4％，65．7％的病例T分期下降，淋巴结阴转率为55．6％。根治切除34例，其中腹会阴联合切除18例，保肛手术16例，保肛率为45．7％。姑息性Hartmann术1例。随访至今，肝转移2例，根治切除术后无1例局部复发。保肛患者肛门功能良好。结论 对低位局部进展期直肠癌患者采用新辅助治疗，可使肿瘤分期降低，提高手术切除率和保肛率。     

盆腔脏器切除术治疗复发直肠癌

目的：探讨盆腔脏器切除术治疗复发直肠癌的疗效。方法：对1984年至2000年复发直肠癌患49例行盆腔脏器切了作术的临床资料及生存资料进行分析，结果：全组无手术死亡，R0切除率为91．8％，手术并发症发生率为12．2％，本组总的3年生存率为82．4％，5年生存率为48．7％，其中45例获得R0切除患的3年生存率为83．5％，5年生存率为59．5％，17例行全盆腔脏器切除术患的3年生存率为72．7％，5年生存率为45．5％，结论：盆腔脏器切除术是治疗复发直肠癌的有效方法，严格选择病例，确保R0切除，妥善重建泌尿和消化通道及妥善覆盖盆腔，是获得满意疗效，降低术后并发症发生率的关键。     

新辅助放化疗联合盆腔脏器切除术治疗45例复发性直肠癌

目的：探讨新辅助放化疗联合盆腔脏器切除术在复发性直肠癌治疗中的价值。方法：对45例复发直肠癌患者采用新辅助放化疗方案治疗常规分割放疗,治疗结束后4～6周进行盆腔脏器切除手术。结果：经新辅助放化疗后,病理完全缓解9例,肿瘤平均缩小38.4%,68.9%的病例T期下降。全组R0切除率为82.2%,手术并发症为20.0%,3年生存率为80.0%,5年生存率为44.4%。结论：新辅助放化疗联合盆腔脏器切除术是治疗复发性直肠癌的有效方法,通过降低肿瘤病期,提高手术切除率,从而提高患者生存率。     

直肠癌术后局部复发综合治疗的疗效分析

目的：分析直肠癌根治术后局部复发的类型、综合治疗的疗效及预后。方法：对直肠癌术后局部复发、以往未接受过放疗的66例病人进行疗效分析。原手术方式为经腹直肠切除术45例(Dixon术40例，Parks术5例)，腹会阴直肠切除术21例。经腹直肠切除术后复发以吻合口为主(37／45，82．2％)，腹会阴直肠切除术后复发则以盆腔或会阴为主(19／21，90．5％)。复发后盆腔放疗中位剂量为40(20—64）Gy，临床症状缓解中位剂量26(10～52)Gy。其中26例在放疗过程中或之后接受过中位7个(2～12)疗程以5-FU为主的化疗。有22例放疗后获补救手术机会。结果：全组中位生存期24个月。Kaplan-Merier法计算生存率，放疗后1、3年总生存率分别为72．2％、17．9％。单因素分析并Log rank检验生存率差异，显示生存率与原发病变的期别、术后复发时间、复发部位及是否加用化疗无关，而仅与是否再次行补救手术有关。放疗后加用补救手术者3年生存期明显较长，为36．0％比8．8％(P=0．016)。结论：直肠癌根治术后局部复发者，放疗具有良好的姑息减症的作用；对部分经腹直肠切除术后的复发病例，放射治疗加补救手术能明显延长生存期。     

应用盆腔脏器联合切除术治疗局部复发型直肠癌

目的 评价盆腔脏器联合切除术对局部复发型直肠癌的治疗意义。方法 对我院33例局部复发型直肠癌应用盆腔脏器联合切除术治疗的病例进行回顾性总结。结果 33例患中17例接受全盆腔脏器切除术治疗，14例接受后盆腔脏器切除术；2例为直肠癌合并输尿管下段切除。29例（87．9％）手术为根治术，手术死亡率3．0％。盆腔受累最多的器官是骶前组织和阴道。术后约88．9％的患疼痛症状消失。8例（24．2％）再次复发，并再用手术。全组2、3、4年生存率分别为36．4％、21．2％、18．2％。结论 积极的盆腔脏器联合切除术可以明显改善局部复发型直肠癌的预后，提高术后生活质量。     

低剂量奥沙利铂并氟脲嘧啶对晚期复发直肠癌放疗增敏作用的临床观察

目的：观察奥沙利铂（L-OHP）并5-氟脲嘧啶、甲酰四氢叶酸钙（5-Fu／LV）配合放疗治疗晚期复发直肠癌患者的增效作用与毒性反应。方法：23例无法手术的晚期复发直肠癌患者进行盆腔放疗，在放疗的第1、5同前一天开始给予L-OHP30mg／m。静滴0．5h，LV100mg／m^2和5-Fu375mg／m^2静滴4h，连用4d。25例单纯放疗者为对照组。结果：放疗结束时，观察组局部症状缓解率较对照组高，尤其对会阴区下坠疼的改善明显（P〈0．05），且转移症状亦有所缓解。两组有效率分别为78．3％、48％（P〈0．05），完全缓解分别为8．7％、4．0％。主要毒副反应是消化道反应、神经毒性、静脉炎，骨髓抑制。结论：利用低剂量L-OHP并5-Fu／LV的增敏作用配合放疗治疗晚期、复发直肠癌可提高近期疗效，改善症状，尤其对于伴远外转移者，为理想、安全的治疗手段。     

三维适形放射治疗结合化疗治疗直肠癌术后复发疗效观察

目的 探讨三维适形放射治疗结合化疗治疗直肠癌术后复发的疗效。方法 回顾性分析56例直肠癌术后复发患者采取三维适形放射治疗(2Gy／次,5次／周,总剂量66～68Gy,6～7周完成)结合化疗(5-氟尿嘧啶0．75g／m^2,d1-5和d29-33;顺铂40mg／m^2,d1-3和d29-31)的疗效,生存分析采用Kaplan-Meier法。结果 患者1、2、3年肿瘤局部控制率分别为87．5％、66．1％、38．2％;1、2、3年生存率分别为88．3％、66．8％、44．2％,中位生存期25．3个月;1、2、3年无瘤生存率分别为82．7％、56．6％、30．1％。急性放射反应主要是急性放射性肠炎,多为1～2级。无晚期放射反应发生。结论 三维适形放射治疗结合化疗是治疗直肠癌术后复发的有效治疗方法。     

术前化疗和放疗、选择性术中放疗和手术切除以治疗结肠直肠癌晚期盆腔复发

作者对43例结肠直肠癌伴盆腔复发采用下列方案治疗:(1)术前给盆腔外束放疗(EBRT)5周以及静脉注射5-FU和/或顺铂;放疗量为45Gy,分25次照射;5FU量为250～300mg/m~2,顺铂量为4mg/m~2,半数病人仅用5-FU。(2)手术切除复发灶。21例并在术中给放疗20～40Gy。(3)术后辅佐化疗,14例采用5-FU化疗。全组中,22例男性,21例女性,平均年龄56.2岁(32～79岁)。34例为直肠癌,9例为乙状结肠癌。 结果 (一)切除率和切缘 95％病例原保留了肛括约肌。化疗放疗后,3例病灶仍进展,列为不能手术。在余下的40例中,7例病灶不能切除(18％),     

全盆腔脏器切除术治疗直肠癌术后盆腔局部复发

目的评价全盆腔脏器切除术(total pelvic exenteration，TPE)治疗盆腔局部复发直肠癌(locally recurrent rectal cancer，LRRC)的疗效。方法对1989-2003年行TPE治疗的35例直肠癌患者的临床资料进行分析。结果行TPE30例、保肛TPE2例、TPE联合骶、尾骨切除2例、TPE联合半骨盆切除1例。根治性切除率80％，手术死亡率3％，术后盆腔再复发率48％。全组术后5年生存率16％，根治性切除组为19％，无淋巴结转移者5年生存率24％，有淋巴结转移者为0。结论TPE手术成功的关键在于严格的适应证选择和作到真正的根治性切除。     

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.     

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.