骨质疏松性椎体压缩骨折行椎体成形术后再发伤椎塌陷的影响因素分析

目的探讨骨水泥强化手术治疗骨质疏松性椎体压缩骨折(Osteoporotic vertebral compression fractures,OVCF)后,再发伤椎塌陷的影响因素。方法回顾性分析我院2014-07-2016-07行PVP/PKP手术治疗的152例OVCF患者,术后19例再发伤椎塌陷(12.5%)。统计所有患者的性别、年龄、体重肥胖指数(BMI)、骨密度、术前是否有椎体内骨坏死、手术方式、术中骨水泥用量、骨折区填充情况等因素,作为自变量;将伤椎塌陷作为因变量,进行单因素分析和多因素Logistic回归分析。结果单因素分析显示,骨密度、椎体内存在骨坏死、手术方式为PVP/PKP、骨水泥分布、骨折区的骨水泥填充情况等相关因素,均存在显著性差异(P0.05);多因素Logistic回归分析显示,椎体内存在骨坏死、PKP手术、骨水泥呈团块状分布、骨折区填充不足,均为术后再发伤椎塌陷的独立危险因素之一。结论伤椎内存在骨坏死、PKP手术、骨水泥呈团块状分布、骨折区的骨水泥填充不足,均是引起OVCF术后再发伤椎塌陷的独立危险因素。     

椎体内部强化术后术椎塌陷的危险因素分析

目的 :探讨椎体内部强化术,包括经皮椎体成形术(PVP)、椎体后凸成形术(PKP),术后术椎塌陷的发生率、独立危险因素以及预防措施。方法:回顾性分析2012年1月至2013年6月经椎体内部强化术治疗并获得随访的154例单节段骨质疏松性椎体压缩骨折(OVCF)患者的临床资料,其中男65例,女89例,年龄57~90岁,平均(76.20±9.35)岁。随访时间6~30个月,平均(15.43±6.81)个月,术后随访患者均接受X线检查,部分患者接受MRI检查。分析与术椎塌陷相关的可能危险因素,包括性别、年龄、手术方式(PVP或PKP)、骨质疏松程度T评分、术椎节段水平、是否合并椎体骨坏死、术椎骨水泥填充模式、术椎前缘高度恢复率。并将可能的危险因素作为研究对象,采用多因素Logistic逐步回归分析法筛选影响术椎塌陷的独立危险因素。结果:随访周期内共发现29例发生术椎塌陷,术椎塌陷的发生率为18.83%。多因素Logistic逐步回归分析显示手术方式(OR=0.171,P=0.010),骨质疏松程度T评分(OR=0.242,P=0.024),是否合并椎体骨坏死(OR=12.225,P=0.003),术椎骨水泥填充模式(OR=10.461,P=0.000)以及术椎前缘高度恢复率(OR=0.316,P=0.019)是影响术椎塌陷的独立危险因素。结论:椎体内部强化术后术椎塌陷的发生率较高,其发生率与多种因素相关,其中手术方式、骨质疏松程度T评分、是否合并椎体骨坏死、术椎骨水泥填充模式、术椎前缘高度恢复率是影响术椎塌陷的独立危险因素。术前严格筛选患者,术中注重骨水泥的对称性均匀分布,术后积极抗骨质疏松治疗,可降低术后术椎塌陷的发生率。     

PVP治疗骨质疏松性椎体压缩骨折术后形成团块样骨水泥的相关因素分析

目的探讨经皮椎体成形术(Percutaneous vertebroplasty,PVP)治疗骨质疏松性椎体压缩骨折术后形成团块样骨水泥的影响因素。方法回顾性分析自2016-01—2019-06采用PVP治疗的875例骨质疏松性椎体压缩骨折,213例术后出现团块样骨水泥(团块样组),662例术后出现非团块样骨水泥(非团块样组)。比较2组在年龄、性别、病程、是否有外伤史、骨折部位、是否合并骨皮质连续性中断、骨折形态、骨折程度、是否合并椎体裂隙征、骨水泥注入量方面的差异。结果 875例均顺利完成手术,单因素分析结果显示团块样组与非团块样组在年龄、病程、是否合并骨皮质连续性中断、骨折类型、骨折程度、是否合并椎体裂隙征、骨水泥注入量方面比较差异有统计学意义(P0.05)。多因素Logistic回归分析显示病程较长、骨折程度重、合并椎体裂隙征、骨水泥注入量较多是骨质疏松性椎体压缩骨折PVP术后合并团块样骨水泥的危险因素(P0.05)。结论病程较长、骨折程度重、合并椎体裂隙征、骨水泥注入量较多是骨质疏松性椎体压缩骨折PVP术后出现团块样骨水泥的危险因素。     

椎体后凸成形术治疗骨质疏松椎体压缩骨折术后非手术椎体新发骨折的相关因素分析

目的:探讨椎体后凸成形术治疗骨质疏松椎体压缩骨折术后非手术椎体新发骨折的相关因素.方法:回顾研究2005年1月～2009年12月我中心收治的102例行椎体后凸成形术治疗骨质疏松椎体压缩骨折患者的临床资料及随访结果,根据随访结果按有无新发椎体骨折出现将患者分成再骨折组及未骨折组(对照组),分析比较两组患者在一般情况(性别、年龄、骨密度、术前骨折椎体数目、骨折压缩程度、腰椎侧凸畸形及脊柱矢状面后凸角)、手术因素(强化椎体个数、手术入路、骨水泥量、骨水泥渗漏及椎体高度恢复程度)、外伤史、长期使用糖皮质激素史方面的差异.应用单因素方差分析及卡方检验分析诸因素与非手术椎体再骨折的相关性,将各相关因素引入Logistic回归分析,分析术后非手术椎体再骨折的主要因素.结果:所有患者均获2年以上随访,随访中共有20例患者先后出现非手术椎体再次骨折,再骨折率为19.6％,单因素分析显示骨密度、术前骨折椎体数目、手术强化椎体个数、骨折压缩程度、骨水泥渗漏及长期使用糖皮质激素史与术后非手术椎体骨折相关(P＜0.05);而年龄、性别、外伤史、骨水泥量、椎体高度恢复程度、腰椎侧凸畸形及脊柱矢状面后凸角与术后非手术椎体骨折无明显相关(P＞0.05).Logistic回归分析显示骨质疏松程度重(OR=0.090)、手术强化椎体数目多(0R=9.682)及长期使用糖皮质激素(0R=9.584)是术后非手术椎体再骨折的高危因素.结论:骨质疏松程度重、手术强化椎体数目多及长期使用糖皮质激素是引起术后非手术椎体新发骨折的高危因素.     

单节段胸腰段骨质疏松性椎体压缩骨折患者PKP术后临近椎体骨折的危险因素分析

目的探讨单节段胸腰段骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fracture,OVCF)患者行经皮椎体后凸成形术(Percutaneous kyphoplasty,PKP)术后临近椎体骨折的危险因素。方法纳入2014-06-2016-06,于我院行PKP手术的185例单节段OVCF患者,随访18个月,将术后发生临近椎体骨折者设为骨折组,其余设为非骨折组。调查两组患者病历资料,明确单节段OVCF患者PKP术后临近椎体骨折的相关因素。结果术后临近椎体骨折22例,骨折率11.89%,平均骨折时间(8.45±1.43)个月;骨折组与非骨折组术前骨密度、术后骨水泥渗漏、年龄、系统抗骨质疏松治疗、骨水泥注入量、伤椎恢复程度差异具有统计学意义(P0.05);多因素logistic回归分析显示,年龄80岁、未进行系统抗骨质疏松治疗、术后骨水泥渗漏、骨密度3.5 T,均是单节段OVCF患者PKP术后临近椎体骨折的独立危险因素。结论单节段OVCF行PKP术后临近椎体骨折发生率较高,高龄、未行正规抗骨质疏松治疗、术后发生骨水泥渗漏、骨密度3.5 T等人群,均会增加临近椎体骨折风险。     

椎体裂隙征与经皮椎体后凸成形术后手术椎体再骨折及相关因素分析

目的 分析经皮椎体后凸成形术（PKP）术后手术椎体再骨折的危险因素并分析其可能的发生机制。方法 将自2010-01-2012-07收治的72例单节段骨质疏松性椎体压缩骨折采用PKP治疗的患者纳入研究,根据术后手术椎体是否发生再骨折将患者分为再骨折组和非再骨折组。结果 所有患者获得随访12-42个月,平均24.5个月。随访期内共发生手术椎体再骨折15.3%（11/72）,2组仅椎体裂隙征和骨质疏松骨密度T值差异有统计学意义（P〈0.05）,而性别、年龄、体重、骨水泥注入量、术前Cobb角、椎体前缘高度丧失值及术后椎体前缘高度恢复率差异均无统计学意义（P〉0.05）。结论 椎体裂隙征和骨质疏松可能与PKP术后手术椎体再骨折有关。     

骨质疏松性胸腰椎压缩骨折经皮骨水泥椎体强化治疗椎体再塌陷情况及相关因素分析

目的调查骨质疏松性胸腰椎压缩骨折(osteoporotic vertebral compression facture,OVCF)经皮骨水泥椎体强化治疗后椎体再塌陷情况并进行相关因素分析。方法纳入2014年2月~2017年4月行经皮椎体后凸成形术(Percutaneous kyphoplasty,PKP)以及经皮椎体成形术(Percutaneous vertebroplasty,PVP)进行椎体强化治疗的254例OVCF患者,随访14~30个月,将末次随访椎体高度丢失≥15%、局部Cobb角丢失≥10°者设为再塌陷组,其余设为未塌陷组,调查两组患者一般资料,经单因素分析与多因素logistic回归分析确定术后椎体再塌陷的独立危险因素。结果 254例OVCF患者椎体再塌陷25例,再塌陷率9.84%;单因素分析显示,两组骨密度T值、骨水泥团块状分布、骨折处骨水泥分布不足、椎体前缘高度比矫正程度、骨水泥未同时与两终板接触、年龄等差异有统计学意义(P0.05);多因素Logistic回归分析显示,骨密度T值(OR=5.564)、骨水泥团块状分布(OR=2.876)、骨折处骨水泥分布不足(OR=2.812)、椎体前缘高度比矫正程度(OR=2.543)、骨水泥未同时与两终板接触(OR=2.559)是术后椎体再塌陷的独立危险因素。结论 OVCF经皮骨水泥椎体强化治疗后存在一定的椎体再塌陷情况,骨密度T值、骨水泥团块状分布、骨折处骨水泥分布不足、椎体前缘高度比矫正程度、骨水泥未同时与两终板接触等均会增加再塌陷风险。     

经皮椎体成形术后手术椎体再发骨折的相关因素分析

目的分析经皮椎体成形术(percutaneous vertebroplasty,PVP)治疗骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fracture,OVCF)患者的临床资料,探讨PVP术后手术椎体再发骨折的相关因素。方法回顾性分析2007年2月至2011年11月因单节段骨质疏松性椎体压缩骨折而行椎体成形术的患者的临床资料,共156例,其中男62例,女94例;年龄56~77岁,平均70.1岁。随访时间12~26个月,平均17.3个月。根据症状、体格检查及影像学资料判断手术椎体是否再发骨折。分析性别、年龄、身高、体重、骨质疏松程度、骨水泥注射量、单侧或双侧注入、骨水泥是否同时接触上下终板、骨水泥是否偏一侧分布、骨水泥椎间盘渗漏以及术前椎体裂隙样变等因素对手术椎体是否出现再发骨折的影响。结果 10例患者发生了手术椎体的再发骨折,4例的新发骨折出现在PVP术后3个月内。术前椎体存在裂隙样变的患者发生手术椎体再骨折的概率明显增高(B=-2.864,OR=0.004,95%CI=0.002-0.05,P=0.000)。骨水泥是否同时接触上下终板、骨水泥是否偏一侧分布、骨水泥有无椎间盘渗漏未增加手术椎体再骨折的风险,差异无统计学意义(P0.05)。结论术前合并裂隙样变的骨折椎体是PVP后手术椎体再发骨折的高风险因素。     

椎体后凸成形术后椎体再骨折相关因素分析研究

背景：椎体后凸成形术（percutaneous kyphoplasty,PKP）治疗骨质疏松性椎体压缩骨折取得了令人鼓舞的临床效果,但是术后椎体发生再骨折时有报道,越来越引起l临床医生的重视。目的：探讨PKP治疗骨质疏松性椎体压缩骨折术后出现椎体再骨折的相关危险因素。方法：回顾性分析209例因骨质疏松性椎体压缩骨折而接受PKP手术治疗患者的相关临床资料,其中男43例,女166例,年龄51～88岁,平均73．0岁。所有患者术后随访时间均为1年以上,根据术后是否出现椎体再骨折分为再骨折组（42例）和对照组（167例）,比较两组患者的相关临床资料,分析椎体再骨折的可能危险因素。结果：两组患者在年龄、性别、身高、体重、平均单椎体骨水泥注入量、术后椎体高度压缩率等方面无统计学差异（P〉0．05）,但是两组患者的骨水泥椎间盘渗漏率和术前骨密度存在统计学差异（P〈O．05）。结论：骨水泥椎间盘渗漏和骨质疏松严重程度可能是骨质疏松性椎体压缩骨折PKP术后椎体再骨折的危险因素。     

球囊扩张椎体后凸成形术后继发相邻节段椎体骨折的危险因素分析

目的分析骨质疏松性椎体压缩骨折球囊扩张椎体后凸成形(PKP)术后继发相邻节段椎体骨折的危险因素。方法选取2006-03—2013-07在本院行PKP治疗并获得1年以上随访,且自愿参与课题的135例骨质疏松性椎体压缩骨折患者作为研究对象。根据随访结果有无出现继发相邻节段椎体新鲜骨折,将研究对象分为骨折组(28例)和对照组(107例)。观察记录2组性别、年龄、BMI指数、骨密度、术前伤椎个数、手术前后Cobb角,以及骨水泥量、骨水泥注射方法(单或双侧注射)、有无骨水泥渗漏、伤椎前缘高度恢复程度。结果多因素Logistic回归分析结果发现低BMI指数、低骨密度、伤椎个数多、骨水泥发生渗漏是引起PKP术后继发相邻节段椎体再骨折的危险因素,差异有统计学意义(P0.05)。其中低骨密度和骨水泥渗漏是最主要的危险因素。结论低骨密度和骨水泥渗漏是引起骨质疏松性椎体压缩骨折PKP术后继发相邻节段椎体骨折的主要危险因素,完善术前准备和坚持抗骨质疏松治疗是主要预防措施。     

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.