喉罩-雷米芬太尼复合七氟醚或丙泊酚麻醉在烧伤整形术中的应用

目的 比较喉罩-雷米芬太尼联合七氟醚与喉罩-雷米芬太尼联合丙泊酚两种麻醉方法在整形手术中应用的优缺点.方法 30例择期疤痕切除植皮术患者,随机均分为喉罩-雷米芬太尼联合七氟醚(S)组与喉罩-雷米芬太尼联合丙泊酚(P)组.静脉诱导置人喉罩后,S组静脉泵入0.15μg·kg-1·min-1雷米芬太尼及吸入2%～3%七氟醚维持麻醉.P组患者通过外周静脉泵入雷米芬太尼0.15μg·kg-1·min-1及丙泊酚6～8 mg·kg-1·h-1维持麻醉.记录患者术中生命体征、苏醒时间、术中及术后并发症发生情况.结果 麻醉诱导后两组患者MAP及HR均明显低于麻醉前水平(P<0.05),S组MAP、HR在切皮前已恢复到术前水平,而P组术中各个时点MAP及HR仍明显低于麻醉前水平及对应时间点的S组(P<0.05).结论 与喉罩-雷米芬太尼联合丙泊酚比较,喉罩-雷米芬太尼联合七氟醚用于烧伤整形手术具有血流动力学更稳定、麻醉更平稳等优点.     

吸入七氟醚与丙泊酚复合雷米芬太尼麻醉在全胃切除手术中的比较

目的 比较七氟醚吸入与丙泊酚复合雷米芬太尼麻醉在全胃切除手术中的应用效果.方法 40例ASA Ⅰ或Ⅱ级择期全胃切除术患者随机均分为七氟醚组(S组)和丙泊酚复合雷米芬太尼组(P组).记录围麻醉期各时点的血流动力学、脑电双频指数(BIS)、麻醉药浓度及用量、麻醉恢复期时间和苏醒期不良反应.结果 麻醉期两组DBP、MAP、HR均较麻醉前显著下降(P<0.05).两组患者术中均能维持足够的麻醉深度(BIS 45～60),术中血流动力学平稳.麻醉恢复期P组躁动、呛咳发生率明显低于S组(P<0.05).结论 七氟醚吸入麻醉或丙泊酚复合雷米芬太尼静脉麻醉均可安全应用于全胃切除手术.     

雷米芬太尼复合丙泊酚与芬太尼复合异氟醚在实施心脏手术快通道麻醉的比较

目的比较雷米芬太尼复合丙泊酚与芬太尼、丙泊酚复合异氟醚用于不停跳心脏手术患者麻醉的应激激素及血流动力学变化。方法26例患者随机均分为雷米芬太尼复合丙泊酚(RP组)和芬太尼复合异氟醚(FI组)两组。分别记录不同时点HR、MAP和血糖(Glu)数值,同时观察相应时点血浆皮质醇(Cor)及促肾上腺皮质激素(ACTH)反应。结果两组患者各观察点血流动力学及应激激素变化组间比较差异无统计学意义。两组患者血浆Cor、ACTH、Glu在心肺转流(CPB)后15min、停CPB后10min与诱导前比较差异有统计学意义(P<0.01),RP组患者术后清醒时间及拔管时间明显早于FI组(P<0.01),但ICU留观时间组间比较差异无统计学意义,且RP组术后疼痛发生率高于FI组(P<0.05)。结论雷米芬太尼复合丙泊酚实施不停跳心内直视手术麻醉,可维持术中血流动力学平稳,停药后清醒快,符合快通道心脏手术麻醉要求,但应加强术后镇痛。     

雷米芬太尼-七氟醚静吸复合全麻在腹腔镜手术的应用

目的观察雷米芬太尼-七氟醚静吸复合全麻在腹腔镜手术的应用中对血流动力学的影响。方法35例全麻下腹腔镜胆囊或妇产科手术病人,男6例,女29例,ASAⅠ或Ⅱ级,以雷米芬太尼1μg/kg、咪唑安定2～3mg、丙泊酚1～2mg/kg、维库溴铵8mg作麻醉诱导后气管插管;麻醉维持为雷米芬太尼0.2μg·kg-1·min-1、丙泊酚2mg·kg-1·min-1微量输注泵恒速输入,吸入1%～2%七氟醚,间断追加维库溴铵4mg。记录诱导前后血流动力学变化。结果注入雷米芬太尼后BP和HR明显下降,注入丙泊酚后进一步下降,气管插管后明显回升,切皮时较插管后下降。气腹后CO、每搏量(SV)和心脏指数(CI)均明显下降;随后逐步回升,放气后恢复或高于基础水平。结论雷米芬太尼和七氟醚均起效快、作用时间短,无蓄积,适用于腹腔镜下的短小手术。     

全麻苏醒拔管期雷米芬太尼靶控输注对心血管反应的影响

目的观察全麻苏醒拔管期雷米芬太尼靶控输注(TCI)对心血管反应的影响。方法择期行妇科手术患者60例,ASAⅠ~Ⅱ级,随机均分为雷米芬太尼组(A组)和生理盐水对照组(B组)。两组患者均接受丙泊酚、维库溴铵、芬太尼、0·8%~1·0%异氟醚复合50%氧化亚氮的全身麻醉。术毕时送至麻醉复苏室(PACU),A组患者TCI输注雷米芬太尼,血浆浓度为1μg/L,B组TCI输注生理盐水作对照。观察苏醒期患者的平均动脉压(MAP)、HR、呼吸恢复时间、睁眼时间和拔管时间。结果A组患者在吸痰、拔管时MAP、HR无明显变化,B组则明显升高(P<0·05);两组患者呼吸恢复、睁眼、拔管时间差异无显著意义。结论TCI雷米芬太尼可抑制全麻苏醒拔管期的心血管反应,平稳苏醒。     

七氟醚、异氟醚不同呼气末浓度对熵和脑电双频指数的影响

目的 观察不同呼气末浓度的七氟醚和异氟醚对熵、脑电双频指数(BIS)及血流动力学的影响.方法 40例ASA Ⅰ或Ⅱ级全麻手术患者随机均分为七氟醚组(Ⅰ组)和异氟醚组(Ⅱ组).麻醉诱导用丙泊酚1 mg/kg,1 min后吸入七氟醚或异氟醚;维持反应熵(RE)、状态熵(SE)、BIS45～55,6 min后置入喉罩.调节吸入浓度使两组患者呼气末浓度分别为0.4、0.6、0.8、1.0和1.3MAC时各维持10 min,记录RE、SE、BIS、HR和MAP.结果 两组患者不同呼气末浓度七氟醚和异氟醚RE、SE、BIS随浓度增加而逐渐下降(P<0.05),HR逐渐减慢、MAP逐渐降低(P<0.05).两组间各指标差异均无统计学意义.RE、SE、BIS间直线相关性随呼气末浓度增大相关系数有增加趋势.结论 熵和BIS均能有效监测七氟醚、异氟醚麻醉深度.     

丙泊酚静脉麻醉与喉罩通气对支气管黏液运输速度的影响

目的比较丙泊酚或七氟醚麻醉应用喉罩或气管插管机械通气时患者支气管黏液运输速度(BTV)的变化。方法 44例全身麻醉下机械通气患者随机均分为四组:喉罩+丙泊酚组(LP组),气管插管+丙泊酚组(TP组),喉罩+七氟醚组(LS组);气管插管+七氟醚组(TS组)。麻醉诱导用药相同,麻醉维持分别采用丙泊酚6～7mg·kg-1.h-1或七氟醚1.5%～2%联合雷米芬太尼0.1～0.2μg·kg-1.min-1。机械通气5、60min时,在纤维支气管镜引导下,用亚甲蓝在右支气管背段黏膜标记,通过测定亚甲蓝的移动速率计算BTV值。结果机械通气5min后,四组BTV值差异无统计学意义。机械通气60min后,TP、LS、TS组BTV值下降(P0.01),LP组BTV值差异无统计学意义;组间比较,四组BTV值LP组TP组LS组TS组(P0.01)。结论丙泊酚静脉麻醉联合喉罩机械通气对呼吸道黏液纤毛传输功能的抑制作用最小。     

鼻咽通气道-面罩自主呼吸下丙泊酚-芬太尼-七氟醚静吸复合全麻用于小儿短小手术的效果:与喉罩自主呼吸的比较

目的 比较鼻咽通气道-面罩和喉罩自主呼吸下丙泊酚-芬太尼-七氟醚静吸复合全麻用于小儿短小手术的效果.方法 择期腹股沟斜疝高位结扎术患儿72例,采用随机数字表法,将患儿分为2组(n=36):鼻咽通气道-面罩组(M组)和喉罩组(L组).静脉注射丙泊酚1.0 mg/kg和芬太尼2.0μg/kg,保留自主呼吸,意识消失后扣上面罩,吸入2 L/min氧气和3％七氟醚,BIS值50 ～ 60时,L组置入2号喉罩,M组经左鼻腔置入鼻咽通气道并扣紧面罩,连接麻醉机行紧闭循环自主呼吸,切皮前5 min静脉注射芬太尼1 μg/kg,术中吸入七氟醚,维持BIS值40 ～ 60.于麻醉诱导前、麻醉诱导后3min、成功置入喉罩或鼻咽通气道即刻、切皮即刻、切皮后3 min、拔出喉罩或鼻咽通气道即刻测定MAP、HR、PETCO2和SpO2,记录置入喉罩或鼻咽通气道的时间和成功情况、苏醒时间、离开手术室时间及不良反应发生情况.结果 与L组比较,插管、拔管时M组MAP、HR降低,置入鼻咽通道时间较短且一次性置入成功率(100％)明显升高,患儿躁动评分及拔管后上呼吸道梗阻发生率明显降低(P＜0.05).结论 鼻咽通气道-面罩自主呼吸下丙泊酚-芬太尼-七氟醚静吸复合全麻用于小儿短小手术,易于建立人工通气道并可维持自主呼吸,对循环功能影响轻微,还可明显减少麻醉恢复期并发症的发生,其效果优于喉罩自主呼吸方式.     

七氟醚复合雷米芬太尼快通道麻醉技术用于青少年脊柱侧弯后路矫形手术

目的 比较七氟醚复合雷米芬太尼与异氟醚复合芬太尼用于青少年脊柱侧弯后路矫形手术的麻醉效果.方法 择期行脊柱侧弯后路矫形手术的患者40例,ASA Ⅰ～Ⅱ级,年龄11～18岁.随机分为两组:异氟醚复合芬太尼组(A组)和七氟醚复合雷米芬太尼组(B组).A组以丙泊酚、芬太尼、维库溴铵和异氟醚维持麻醉;B组以丙泊酚、雷米芬太尼、维库溴铵和七氟醚维持麻醉.根据双频指数(BIS)和血流动力学反应调整麻醉深度.在唤醒前约30 min停用维库溴铵和镇痛药.要求唤醒时停用丙泊酚和吸人麻醉药,唤醒时间为停用丙泊酚和吸入麻醉药到患者双侧脚趾能动的时间.记录唤醒时间、唤醒质量及唤醒期间HR、SBP、DBP、BIS的变化.患者拔除气管导管清醒后随访患者对术中唤醒过程有无记忆.结果 患者的一般情况、唤醒期间HR、SBP、DBP和BIS两组问比较均无统计学差异.两组患者唤醒时BIS明显高于停药前(P＜0.001),但是术后随访发现所有患者对唤醒试验均无记忆.唤醒时间A组26.3 min±10.4 min,B组12.1 min±9.4 min,两组间比较差异有统计学意义(P＜0.01).唤醒成功时,两组的唤醒质量比较无统计学差异(P＞0.05).结论 七氟醚复合雷米芬太尼快通道麻醉技术适合用于行术中唤醒的青少年脊柱侧弯后路矫形手术,其唤醒时间短、术中血流动力学平稳.该麻醉条件下行BIS监测,有助于及时唤醒病人和唤醒后加深麻醉,亦有助于防止术中知晓.     

七氟醚复合雷米芬太尼快通道麻醉在鼻内窥镜手术中的应用

目的观察七氟醚复合雷米芬太尼快通道麻醉在鼻内窥镜手术中的应用效果。方法 60例择期行鼻内窥镜手术患者,年龄21～55岁,随机分为三组,每组20例。Ⅰ组全凭吸入七氟醚麻醉,Ⅱ组丙泊酚复合雷米芬太尼,Ⅲ组七氟醚复合雷米芬太尼。观察三组患者术中、术后血流动力学变化,记录术后拔管时间、清醒时间、术后躁动评分(RS)、意识状态评分(OAA/S)等。结果三组术中血压控制均较满意。术后Ⅱ、Ⅲ组拔管时间及清醒时间较Ⅰ组短,躁动发生率稍低(P0.05)。结论七氟醚复合雷米芬太尼静吸复合麻醉与丙泊酚复合雷米芬太尼全凭静脉麻醉均为鼻内窥镜手术提供安全、快捷、苏醒彻底的快通道麻醉方法。     

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.     

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.     

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.     

Immunomodulation in Transplantation with Photopheresis

Abstract: Photopheresis is a technique in which peripheral blood mononuclear cells, in the presence of a photoacti-vatable compound, are exposed extracorporeally to ultraviolet A light and reinfused, inducing a host autoregula-tory immune response. Experimental work and ongoing clinical studies are helping to define the role of this novel, safe, and non-toxic immunomodulating technology in the field of transplantation.