肝脏异型增生结节的常规超声及超声造影图像分析

目的探讨肝脏异型增生结节的常规超声和CEUS声像图特点及其诊断价值。方法回顾性分析经增强MRI和超声引导下穿刺活检病理证实的39例肝脏异型增生结节患者的常规超声以及CEUS表现。结果常规超声显示39例病灶的平均直径（1.8±1.0）cm;偏低回声占84.62%（33/39）,边界清晰占69.23%（27/39）,质地欠均匀者占64.10%（25/39）,94.87%（37/39）不伴声晕,94.87%（37/39）不伴后方回声增强。常规超声诊断为肝脏异型增生结节13例,诊断正确率33.33%（13/39）。CEUS示动脉期高增强占84.62%（33/39）,其中28例门脉期等增强,延迟期低增强（71.79%,28/39）;2例（5.13%,2/39）动脉期等增强;4例（10.26%,4/39）动脉期低增强。CEUS诊断为肝脏异型增生结节23例,诊断正确率58.97%（23/39）。结论常规超声异型增生结节多表现为边界清晰、质地欠均匀的偏低回声,且不伴声晕及后方回声增强;CEUS多以动脉期高增强、门脉期等增强、延迟期低增强表现为主,CEUS的诊断准确率明显高于常规超声。     

乳腺三阴性非特殊型浸润性癌自动乳腺全容积成像特点

目的 观察乳腺三阴性非特殊型浸润性癌（IC-NST）自动乳腺全容积成像（ABVS）超声特点。方法 回顾性收集经术后病理证实的156例单发IC-NST患者，根据免疫组织化学结果将其分为三阴性（三阴性组）和非三阴性（非三阴性组），对比组间一般资料及ABVS表现。结果 156例中，病变位于左乳76例、右乳80例，三阴性30例（30/156，19.23%）、非三阴性126例（126/156，80.77%）。组间患者年龄、肿瘤体积、淋巴结转移差异均无统计学意义（P均>0.05）；病理组织学分级差异有统计学意义（P<0.001），病灶ABVS冠状面"汇聚征"及后方回声衰减差异有统计学意义（P均<0.05），而微钙化、边缘、形态、方位及Adler血流分级差异均无统计学意义（P均>0.05）。结论 乳腺三阴性IC-NST的ABVS表现有一定特征性，其中乳腺冠状面"汇聚征"及后方回声衰减相比非三阴性IC-NST较为少见。     

对比超声与CT诊断新生儿及婴儿卵巢囊肿

目的 对比观察超声与CT对新生儿及婴儿卵巢囊肿的诊断价值。方法 回顾性分析经出生后手术病理确诊,且术前接受腹部超声和CT检查的34例单发卵巢囊肿患儿,包括24例新生儿（0~28天）和10例婴儿（29~179天）;观察病变超声声像图及CT特征,对比两种方法诊断卵巢囊肿的效能。结果 34个卵巢囊肿中,19个来自左侧卵巢、15个来自右侧卵巢,其中20个存在蒂扭转。超声声像图示复杂型囊肿18个、单纯型囊肿16个。腹部CT示28个呈低密度影、4个呈混杂密度影,2个未检出;16个囊壁增厚,11个可见钙化。超声定性诊断卵巢囊肿的准确率为94.12%（32/34）,定位诊断囊肿来源卵巢侧别的准确率为88.24%（30/34）;诊断卵巢囊肿蒂扭转的准确率为85.00%（17/20）。CT定性诊断卵巢囊肿的准确率73.53%（25/34）,定位诊断准确率55.88%（19/34）;诊断卵巢囊肿蒂扭转准确率55.00%（11/20）。超声与CT定性诊断卵巢囊肿的准确率差异无统计学意义（χ²=0.77,P=0.38）,定位诊断卵巢囊肿准确率（χ²=5.74,P=0.02）及诊断蒂扭转准确率（χ²=4.31,P=0.04）差异均有统计学意义。结论 超声及CT对诊断新生儿及婴儿卵巢囊肿均有一定价值;超声对囊肿内部回声改变更为敏感,定位诊断卵巢囊肿和诊断蒂扭转均优于CT。     

超声在不同分型急性结肠憩室炎诊断中的价值

目的 观察超声诊断单纯型及复杂型急性结肠憩室炎的价值。方法 回顾性分析17例急性结肠憩室炎患者的临床、超声及CT资料,分析超声诊断急性结肠憩室炎的价值。结果 17例中,11例接受超声检查,其中单纯型8例、复杂型3例。7例单纯型超声表现为局部结肠肠壁增厚,结肠边缘见囊袋状凸起,边界清,憩室周围可见高回声包绕;1例病灶位于升结肠,结肠边缘见囊袋状凸起,憩室内见高密度粪石,肠壁增厚伴周围脂肪密度升高,超声漏诊后经CT检出。3例复杂型超声均表现为憩室周围低回声包块,与周围肠管、膀胱分界不清。超声结合临床准确诊断10例(90.91%,10/11)急性结肠憩室炎,包括7例(7/8,87.50%)单纯型和3例(3/3,100%)复杂型。结论 超声有助于诊断急性结肠憩室炎,尤其复杂型急性结肠憩室炎。     

CT引导下经皮穿刺活检食管占位性病变的有效性及安全性

目的 观察CT引导下经皮穿刺活检食管占位性病变的有效性及安全性。方法 回顾性分析37例接受CT引导下经皮穿刺活检的食管占位性病变患者（37个病灶）,统计取材成功率、穿刺病理诊断率及诊断准确率（以术后病理诊断或随访诊断为最终诊断）和术中、术后并发症。结果 37个病灶均穿刺取材成功并获明确病理诊断,32个病理结果为阳性（肿瘤性病变）、5个为阴性（炎性病变或正常组织）,穿刺病理诊断率100%。32个阳性病变穿刺病理诊断与最终诊断结果均一致;5个穿刺阴性病变中,3个与最终诊断一致,2个术后病理均为胃肠间质瘤,穿刺诊断准确率为94.59%（35/37）,假阴性率40.00%（2/5）。术后2例出现少量气胸、3例穿刺针道少量出血,1周后均自然吸收,并发症发生率13.51%（5/37）。结论 CT引导下经皮穿刺食管占位性病变安全、有效。     

胰腺实性假乳头状瘤超声表现及病理特点

目的 观察胰腺实性假乳头状瘤(SPTP)的超声表现及病理特点。方法 回顾性分析37例经术后病理证实的SPTP患者,男7例、女30例,平均年龄(33.6±16.4)岁,观察病灶超声表现及病理特点。结果 37例均为单发病灶,超声呈圆形或类圆形不均质低回声,平均长径(49.43±5.17) mm,平均短径(39.51±4.18) mm;12例位于胰头,位于胰尾11例、胰体10例、胰颈4例;32例边界清,29例形态规则,28例见低或无回声裂隙;26例呈囊实性,21例可见包膜,8例存在钙化;8例见少许点状血流(Adler Ⅰ级),2例见少许条状血流(Adler Ⅱ级),10例边缘有血流(Adler Ⅲ级),17例未见血流(Adler 0级)。3例血清CA199、CA50、CEA及AFP 4项标志物中至少2项高于正常范围,结合超声及病理表现诊断为恶性。大体病理见肿瘤呈类圆形或不规则形,光镜下实性区肿瘤细胞较小且大小一致,排列紧密呈巢片状,细胞核呈圆形或卵圆形,胞质丰富,多数异型性不明显。结论 SPTP超声表现有一定特异性,结合病理表现及血清肿瘤标志物有助于定性诊断。     

动态增强MRI定性诊断乳腺导管上皮非典型增生

目的 观察动态增强MRI（DCE-MRI）定性诊断乳腺导管上皮非典型增生（ADH）的价值。方法 回顾性分析经穿刺活检或局部切除组织活检诊断的64例乳腺单发ADH患者,以手术病理结果为金标准,比较恶性与良性病变患者临床资料及乳腺X线、DCE-MRI征象,分析DCE-MRI预测乳腺恶性ADH的效能。结果 64例乳腺单发ADH中,28例为恶性（恶性组）,36例非恶性（非恶性组）,组间活检方式、病灶最大径、MRI示乳腺实质背景强化（BPE）、乳腺X线表现差异均有统计学意义（P均<0.1）;将上述因素纳入Logistic多因素回归分析,结果显示仅BPE为乳腺恶性ADH的独立影响因素[OR=7.550,95%CI（1.575,36.197）,P=0.011]。DCE-MRI诊断BI-RADS 4A及以下者27例,其中3例为恶性;4A类以上（4B及4C）37例,25例为恶性,诊断敏感度89.29%（25/28）,特异度66.67%（24/36）,阳性预测值67.57%（25/37）,阴性预测值88.89%（24/27）。结论 DCE-MRI可用于定性诊断乳腺ADH;其所示中重度BPE为术后病理恶性的正相关因素。     

胃超声在急诊剖宫产产妇全麻术中的应用

目的 评价胃超声在预测急诊剖宫产术喉罩全麻产妇术中反流及术后24 h恶心、呕吐发生率的价值。
方法 选择需行急诊剖宫产术产妇309例,年龄19～42岁,ASA Ⅱ或Ⅲ 级。所有产妇入室时胃超声图像表现为均匀一致的低回声。入室时超声测量胃窦部横截面积（CSA）,将产妇分为三组：387 mm²≤CSA＜505 mm²组（S组,n=98）;505 mm²≤CSA≤608 mm²组（M组,n=112）;CSA>608 mm²组（L组,n=99）。记录入室时、诱导后即刻、切皮时、胎儿娩出时、关腹时、拔除喉罩时食管中上段pH变化及反流发生情况。记录产妇胃管吸引量,入室时和麻醉结束时胃窦部CSA,并分析入室时胃窦部CSA与胃管吸引量的相关性。记录术后24 h内产妇恶心、呕吐的发生情况。
结果 S组和M组食管中上段pH均大于4.00,未出现术中反流病例;L组有4例（4%）于术者按压上腹部协助胎儿娩出时出现食管中上段反流,反流发生率明显高于S组、M组（P<0.05）。M组和L组胃管吸引量和不同时点胃窦部CSA明显大于S组（P<0.05）,L组明显大于M组（P<0.05）。入室时胃窦部CSA与胃管吸引量呈明显的正相关（r=0.88 P <0.001）。术后24 h L组呕吐发生率明显高于S组和M组（P<0.05）。三组恶心发生率差异无统计学意义。
结论 在严格选择胃超声图像表现为均匀一致低回声病例及术中严密监测的前提下,Supreme双腔喉罩用于胃窦部CSA≤608 mm²急诊剖宫产术产妇术中并未观察到食管中上段反流;而胃窦部CSA>608 mm²时术中发生反流的风险及术后24 h呕吐发生率明显升高,应用时需谨慎。     

局灶性甲状腺炎与甲状腺乳头状癌常规超声及实时剪切波弹性成像表现

目的 对比观察局灶性甲状腺炎与甲状腺乳头状癌（PTC）常规超声及实时剪切波弹性成像（SWE）表现。方法 回顾性分析经病理证实的36例局灶性甲状腺炎及100例PTC患者[其中50例合并桥本甲状腺炎（HT）],对比其常规超声声像图表现及杨氏模量值。结果 136例甲状腺结节均为实性。局灶性甲状腺炎与PTC患者之间,结节位置、数量、直径、形态及内部钙化差异均无统计学意义（P均>0.05）,边界模糊、内部回声及纵横比>1差异均有统计学意义（P均<0.05）。局灶性甲状腺炎与PTC之间杨氏模量值最大值（E_max）、最小值（E_min）及平均值（E_mean）差异均无统计学意义（P均>0.05）;PTC患者中,合并HT者与无HT者之间SWE杨氏模量值E_max、E_min及E_mean差异均无统计学意义（P均>0.05）。结论 局灶性甲状腺炎与PTC常规超声表现存在一定差异,有助于鉴别诊断;SWE对二者无明显鉴别诊断价值,是否合并HT不影响SWE诊断PTC。     

微导丝贯穿法联合臭氧介入治疗输卵管阻塞性不孕症

目的 观察微导丝贯穿法联合臭氧介入治疗输卵管阻塞性不孕症效果。方法 回顾性分析149例输卵管阻塞性不孕症患者资料,其中A组（n=44）接受常规输卵管再通术（FTR）,B组（n=51）接受微导丝贯穿法FTR,C组（n=54）接受微导丝贯穿法联合臭氧FTR治疗;比较治疗后1个月各组输卵管复通率及1年内自然妊娠率。结果 治疗后1个月,A、B、C组输卵管复通率分别为63.38%（45/71）、80.22%（73/91）及92.78%（90/97）,各组依次升高（P均＜0.05）;1年内A、B、C组自然妊娠率分别为20.45%（9/44）、27.45%（14/51）及48.15%（26/54）,C组高于A、B组（P均＜0.05）,且A、B组差异无统计学意义（P=0.427）。结论 微导丝贯穿法联合臭氧介入治疗输卵管阻塞性不孕症效果优于常规FTR及单独微导丝贯穿法FTR。     

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.     

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.     

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.     

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.     

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.     

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.