脊椎血管瘤目的外科治疗策略

[目的]探讨脊椎血管瘤的外科治疗策略.[方法]回顾1997年10月～2008年10月间的33例脊椎血管瘤.女19例,男14例;平均年龄54岁.13例患者因局部疼痛就诊;12例截瘫;8例存在神经根刺激症状和局部疼痛.9例患者为单纯局部疼痛,影像学无脊髓及神经根压迫,行经皮椎体成形术.24例患者存在硬膜囊或神经根压迫、软组织包块较大、或脊柱不稳,接受开放手术.其中,9例肿瘤主要侵犯椎体、伴有不同程度椎体压缩骨折或存在椎旁软组织包块,行前路手术治疗;12例肿瘤主要累及附件及椎体后缘.肿瘤突入椎管内压迫脊髓及神经根而无明显椎体压缩骨折,行后路手术,其中4例椎体内病灶较大,术中直视下行椎体成形术;3例肿瘤广泛累及椎体及附件,肿瘤侵入椎管内,椎体侧方存在软组织包块,行前后路联合手术.3例术前行节段动脉栓塞术.[结果]9例行单纯椎体成形的患者无围手术期并发症,平均随访41个月,疼痛均完全或明显缓解.开放手术的24例,无围手术期死亡患者.前路手术平均出血为2 739 ml,后路手术平均出血为1 619 ml(P=0.12).1例腰椎前路手术患者术后出现椎体周围血肿并继发下肢静脉血栓.1例胸椎后路手术患者术后出现血肿后截瘫加重.1例腰椎后路手术患者出现伤口感染.19例患者开放手术前存在疼痛,手术后17例疼痛完全或明显缓解.12例截瘫患者的Frankel脊髓功能评分提高1～2级.行开放手术患者平均随访48个月.X线片示内固定物无移位、折断.1例死于其他肿瘤.影像学证实肿瘤复发或发展者4例,2例尤症状给予观察,1例因疼痛行放疗,1例因截瘫再次手术.[结论]根据脊椎血管瘤患者症状产生的病因以及患者一般情况,应用多种相应外科技术治疗脊椎血管瘤,可以取得较好的临床效果.     

脊柱肿瘤的手术治疗

目的 :探讨对于脊柱肿瘤一期全脊椎切除及脊柱稳定性重建的手术方法和临床效果。方法 :对 12例脊柱肿瘤行前、后路或前、后联合入路Ⅰ期全脊椎切除、脊髓减压 ,椎间植骨融合、内固定术。结果 :术后 11例获得随访 ,按照Frankel分级较术前均有 1级以上提高 ,所有患者局部疼痛症状消失。术后复查平均植骨融合时间 3个月。1例脊索瘤术后 1年复发 ,1例巨细胞瘤术后 9个月复发。结论 :针对脊柱肿瘤的性质、部位 ,通过不同的手术入路行一期全脊椎切除、植骨融合内固定 ,彻底切除肿瘤 ,重建脊柱稳定性并体现了个体化的治疗方向     

经后路一期全脊椎切除治疗胸椎单脊椎肿瘤的临床疗效

目的：探讨胸椎单脊椎肿瘤通过后路一期病椎切除、单纯植骨支撑融合或钛网支撑植骨融合、后路椎弓根钉系统内固定，达到切除病灶并同时重建脊柱稳定性的可行性。方法：对18例胸椎单脊椎肿瘤患者行后中一期全脊椎切除、环脊髓减压，同时进行后路单纯植骨融合或椎间钛网支撑植骨，应用后路CD、TSRH或Scofix椎弓根钉系统内固定。男3例，女15例；年龄14－58岁，平均23岁。T41例，T51例，T62例，T84例，T93例，T104例，T112例，T121例。病理诊断：动脉瘤样骨囊肿4例，血管瘤2例，骨母细胞瘤2例，神经鞘瘤1例，骨巨细胞瘤5例，单发骨髓瘤1例，转移瘤3例。术前Frankel分级：A组6例，B级7例，C级3例，E级2例。结果：术后随访3个月－2年，16例脊髓功能障碍者，12例完全恢复，4例部分恢复，所有患者局部疼痛均消失。1例术后出现一过性瘫痪加重，1例出现脊柱滑脱。术后平均植骨融合时间为3个月。1例骨巨细胞瘤患者复发；1例神经鞘瘤患者1年后局部出现包块，取活检报告为恶性肿瘤（未报组织学类型），4个月后死亡；1例肺癌转移患者术后6个月死亡；其余病例存活至今。结论：对于胸段脊椎肿瘤行后路手术可一期实施单脊椎肿瘤彻底切除，并通过椎体间钛网支撑或植骨及后路椎弓根钉系统内固定重建脊柱的稳定性，效果满意。     

侵袭性脊柱血管瘤的外科治疗

目的探讨侵袭性脊柱血管瘤的外科手术方式和临床价值。方法 9例有神经损害的侵袭性血管瘤患者,术前经X片、CT和(或)MRI检查,诊断明确,均行后路减压联合开放椎体成形术治疗,其中3例先行后路减压内固定术(A组),6例先行开放椎体成形术(B组),比较患者术前、术后VAS疼痛评分、Frankel脊髓损伤分级评分、两种手术方式术中出血量及手术时间。结果 9例患者术后VAS评分由术前平均7.5分降至术后平均2.3分,术后神经功能不同程度恢复,术中出血量A组80~100ml,B组50~90 ml,手术时间A组90~100 Min,B组50~100 Min,两组术后复查均无骨水泥渗漏,无椎管内占位,随访7~48个月,平均21.3个月,所有患者术后肿瘤未见复发,病变椎体高度未见丢失。结论开放椎体成形术联合后路减压内固定治疗侵袭性脊柱血管瘤效果良好,先行开放椎体成形术可减少术中出血量,而先行椎板切除减压能进一步降低椎体后壁破损患者的脊髓损伤的风险。     

胸椎单脊椎原发性肿瘤后路全脊椎切除的临床疗效

目的观察胸椎单脊椎原发性肿瘤后路一期病椎切除,单纯植骨融合、填充自体骨钛网或填充骨水泥钛网支撑,后路椎弓根钉系统内固定的临床疗效。方法1997年2月~2005年4月对26例胸椎单脊椎原发性肿瘤患者实施后路一期病椎切除、脊髓减压,同时对良性、低度恶性肿瘤进行前路单纯植骨融合、填充自体骨钛网支撑,高度恶性肿瘤采用骨水泥钛网支撑,所有患者实施后路植骨,应用椎弓根钉系统内固定重建脊柱稳定性。本组男15例,女11例,平均年龄22岁(14~52岁)。其中,动脉瘤样骨囊肿5例,骨囊肿2例,血管瘤5例,骨髓瘤3例,嗜酸性白细胞肉芽肿2例,骨巨细胞瘤6例,骨肉瘤3例。术前Frankel分级A级2例,B级8例,C级7例,D级3例,E级6例。结果术后随访时间6个月~8年。术前疼痛24例,术后无疼痛22例(91.7%),疼痛减轻2例,疼痛缓解率95.8%。20例脊髓功能障碍者,14例完全恢复,5例部分恢复,1例无恢复,脊髓功能改善率95%。6例患者出现8个术中和术后并发症,并发症发生率38.4%。结论胸段单脊椎原发性肿瘤后路一期全脊椎切除术安全可行,可有效控制肿瘤的局部复发、缓解疼痛、提高生活质量、延长寿命,临床疗效满意。     

一期后路全脊椎切除术治疗伴脊髓压迫的肾源性脊柱转移癌

目的探讨一期后路全脊椎切除术治疗伴有脊髓压迫的肾源性脊柱转移癌的外科策略及临床疗效。方法2003年1月—2012年12月,第二军医大学附属长征医院骨肿瘤科共收治35例伴有脊髓压迫的肾癌脊柱转移患者,均行一期后路全脊椎切除术、脊髓减压并内固定重建术。对所有患者病史、影像学资料、手术时间、术中出血量、切除重建策略、手术并发症及临床疗效进行分析。采用美国脊髓损伤协会(ASIA)分级评价患者神经功能状况,采用视觉模拟量表(VAS)评分对患者疼痛程度进行评估。所有患者术后接受放化疗以及双膦酸盐治疗。结果所有手术顺利完成,手术时间为(296±35)min,术中出血量为(2 160±240)m L,术中无大血管或脊髓损伤,无脑脊液漏等并发症。所有患者均获得随访,随访时间为(73.2±8.7)个月。术后1例ASIA A级患者恢复至B级;3例ASIA B级患者恢复至C级、D级各1例,1例因压迫时间过长无恢复;2例ASIA C级患者1例恢复至D级,1例仍然为C级;11例ASIA D级患者9例恢复至E级,2例仍然为D级;18例ASIA E级患者无变化。所有患者术后VAS评分均降低,与术前相比差异有统计学意义(P0.05)。随访时1例患者术后18个月因肿瘤复发压迫颈髓致瘫痪,并肺部转移,致呼吸衰竭死亡;2例患者复发,1例行手术治疗,1例放弃治疗;3例患者带瘤生存;其余患者末次随访时未见复发征象。结论一期后路全脊椎切除术治疗伴脊髓压迫的肾癌脊柱转移能够安全有效地解决患者局部压迫症状,改善其神经功能,术后综合治疗能延长患者的生存期。     

脊椎血管瘤的外科治疗策略

[目的]探讨脊椎血管瘤的外科治疗策略。[方法]回顾1997年10月～2008年10月间的33例脊椎血管瘤。女19例,男14例;平均年龄54岁。13例患者因局部疼痛就诊;12例截瘫;8例存在神经根刺激症状和局部疼痛。9例患者为单纯局部疼痛,影像学无脊髓及神经根压迫,行经皮椎体成形术。24例患者存在硬膜囊或神经根压迫、软组织包块较大、或脊柱不稳,接受开放手术。其中,9例肿瘤主要侵犯椎体、伴有不同程度椎体压缩骨折或存在椎旁软组织包块,行前路手术治疗;12例肿瘤主要累及附件及椎体后缘,肿瘤突入椎管内压迫脊髓及神经根而无明显椎体压缩骨折,行后路手术,其中4例椎体内病灶较大,术中直视下行椎体成形术;3例肿瘤广泛累及椎体及附件,肿瘤侵入椎管内,椎体侧方存在软组织包块,行前后路联合手术。3例术前行节段动脉栓塞术。[结果]9例行单纯椎体成形的患者无围手术期并发症,平均随访41个月,疼痛均完全或明显缓解。开放手术的24例,无围手术期死亡患者。前路手术平均出血为2739ml,后路手术平均出血为1619ml(P=0.12)。1例腰椎前路手术患者术后出现椎体周围血肿并继发下肢静脉血栓。1例胸椎后路手术患者术后出现血肿后截瘫加重。1例腰椎后路手术患者出现伤口感染。19例患者开放手术前存在疼痛,手术后17例疼痛完全或明显缓解。12例截瘫患者的Frankel脊髓功能评分提高1～2级。行开放手术患者平均随访48个月。X线片示内固定物无移位、折断。1例死于其他肿瘤。影像学证实肿瘤复发或发展者4例,2例无症状给予观察,1例因疼痛行放疗,1例因截瘫再次手术。[结论]根据脊椎血管瘤患者症状产生的病因以及患者一般情况,应用多种相应外科技术治疗脊椎血管瘤,可以取得较好的临床效果。     

一期后路全脊椎切除并内固定矫治胸腰椎陈旧性骨折脱位

[目的]探讨一期后路全脊椎切除并内固定矫治胸腰椎陈旧性骨折脱位伴前后、侧方移位畸形及脊髓损伤的外科疗效。[方法]2007年1月～2009年6月共收治12例胸椎及胸腰段脊椎陈旧性骨折脱位伴前后、侧方移位畸形及脊髓损伤患者,均为男性;年龄19～57岁,平均32.6岁。伤椎部位:胸椎5例,胸腰段7例。骨折类型按照Denis分型:所有患者均为骨折脱位型,表现为矢状面前后脱位,其中5例同时伴有冠状面侧方移位畸形。患者术前均有程度不等的腰背部疼痛,局部压痛、叩击痛。神经功能按Frankel分级:A级9例,B级2例,C级1例。伤后至手术时间为4周至2年不等,术前平均病程6.3个月。所有患者一期经后路置入4对椎弓根钉,行伤椎全脊椎切除,环脊髓减压,椎间撬拔撑开复位,可调式中空笼状钛合金人工椎体或钛网复合自体碎骨粒置入,后路椎弓根钉棒系统行邻近椎节固定,一期矫形重建脊柱稳定性。观察术后局部疼痛缓解、脊髓神经功能恢复情况;X线检查了解胸腰椎前后、侧方移位畸形矫治及植骨融合情况。[结果]随访12～40个月,平均23个月。所有患者术后疼痛缓解,脊髓神经功能无加重损伤,不完全损伤的3例患者脊髓神经功能得到不同程度恢复。术后影像学检查提示:脊柱内固定物在位,在矢状面和冠状面上脱位畸形已矫正,脊柱序列恢复良好。所有患者在术后6个月内均获得骨性融合。[结论]一期后路全脊椎切除并内固定能彻底减压、缓解疼痛,能有效矫正畸形、恢复脊柱序列、重建脊柱稳定性,有效地矫治胸腰椎陈旧性骨折脱位。     

一期后路全脊椎切除并内固定矫形治疗胸腰椎疾患

目的 观察一期后路全脊椎切除并内固定矫形治疗胸腰椎疾患的疗效.方法 对17例胸腰椎疾患(6例陈旧性脊柱骨折脱位,4例全脊椎结核,5例脊柱侧后凸畸形,2例全脊椎肿瘤)全脊柱切除的疗效进行回顾性分析.其中14例伴有后凸或侧后凸成角畸形,12例病变节段以下完全或不完全性瘫痪.对所有患者一期经后路行病椎全脊椎切除,环脊髓减压、...     

多节段椎管内肿瘤的外科治疗

目的探讨多节段椎管内肿瘤的特点、诊断、手术方法及临床效果。方法 15例多节段椎管内肿瘤患者行MRI检查示肿瘤组织压迫脊髓。均行后路常规手术入路切除肿瘤,行钉棒系统内固定。结果 15例均获得随访,时间12～50个月。术后影像学检查植骨融合良好。术后6个月按Frankel分级:C级2例恢复至D级1例、E级1例,D级13例恢复至E级10例,3例无恢复。结论经后路全椎板切除肿瘤治疗多节段椎管内肿瘤,患者术后症状大多数可以明显改善。多节段椎板切开术后应给予脊柱内固定,以保持脊柱的稳定性。     

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.