Power spectral analysis of the electroencephalographic and hemodynamic correlates of propofol anesthesia in the rat: Intravenous infusion

Based on the tail-flick response to noxious thermal stimuli, we determined in the present study that effective antinociception could be achieved in adult male Sprague-Dawley rats 15 min after intravenous infusion of propofol at 60 mg/kg/h. Simultaneous power spectral analysis of the electroencephalographic (EEG) and systemic arterial pressure signals further revealed a concomitant depression of the activity of all EEG frequency bands (δ, θ, , β), alongside hypotension, negative inotropic and chronotropic actions, and attenuated baroreceptor reflex and vasomotor activity. These effects were congruent with a plasma concentration of propofol in the arterial blood of 1.70 ± 0.13 μg/ml, as determined by high-performance liquid chromatography.     

Dexmedetomidine versus propofol for prolonged sedation in critically ill trauma and surgical patients

Backgroundand Purpose: Currently, dexmedetomidine versus propofol has primarily been studied in medical and cardiac surgery patients with outcomes indicating safe and effective sedation. The purpose of this study was to assess the efficacy of dexmedetomidine versus propofol for prolonged sedation in trauma and surgical patients.MethodsThis was a single-center prospective study conducted in the Trauma/Surgical Intensive Care Unit (ICU) at a Level I academic trauma center. It included patients 18 years of age or older requiring mechanical ventilation who were randomly assigned based on unit bed location to receive either dexmedetomidine or propofol. The primary outcome was duration of mechanical ventilation. Secondary outcomes included mortality; proportion of time in target sedation; incidence of delirium, hypotension, and bradycardia; and ICU and hospital length of stay (LOS).ResultsA total of 57 patients were included. Baseline characteristics were similar between groups. There was no significant difference in duration of mechanical ventilation (median [IQR]) between the dexmedetomidine (78.5[125] hours) and propofol (105[130] hours; p = 0.15) groups. There was no difference between groups in ICU mortality, ICU and hospital LOS, or incidence of delirium. Safety outcomes were also similar. Patients in the dexmedetomidine group spent a significantly greater percentage of time in target sedation (98[8] %) compared to propofol group (92[10] %; p = 0.02).ConclusionsOur results suggest that, similar to medical and cardiac surgery patients, dexmedetomidine and propofol are safe and effective sedation agents in critically ill trauma and surgical patients; however, dexmedetomidine achieves target sedation better than propofol for this specific population.     

Plasma histamine levels during induction of anesthesia with propofol in dogs

We examined a property of emulsion formation of propofol (ICI 35868) to release histamine into circulating plasma in dogs. Plasma histamine was measured with radioimmunoassay before (baseline), and 1, 5 and 10min after the administration of 15mg·kg^–1 propofol. There were no significant differences between the plasma histamine levels at 1, 5 and 10min after the administration of propofol and the baseline level. We conclude that the emulsion formation of propofol of 15mg·kg^–1 does not release histamine during induction of anesthesia in dogs.(Mitsuhata H, Shimizu R: Plasma histamine levels during induction of anesthesia with propofol in dogs. J Anesth 7: 206–209, 1993)     

异丙酚复合芬太尼维持麻醉对脑代谢的影响

观察异丙酚复合芬太尼维持麻醉对脑代谢的影响。方法： 择期手术病人８ 例, 芬太尼、硫贲妥钠、维库溴铵诱导插管, 静脉联接Ｇｒａｓｅｂｙ 微泵异丙酚８ ｍｇ／ （ｋｇ·ｈ） , 芬太尼１ μｇ／ （ｋｇ·ｈ）维持麻醉。连续监测ＭＡＰ、心电图、脉搏氧饱和度和呼气末二氧化碳分压, 同步采集动脉血和颈内静脉血作血气分析, 计算动－ 静脉氧含量差（Ｄａ － ｖＯ２） 和脑氧摄取率（ＥＲＯ２） 。结果： 异丙酚麻醉维持平稳, Ｄａ － ｖＯ２ 和ＥＲＯ２ 在给药３０ ｍｉｎ 、６０ ｍｉｎ 较气管插管后５ ｍｉｎ 无明显改变, 有平均动脉压下降和心动过缓。结论： 异丙酚复合芬太尼维持麻醉可保持脑氧供需平衡稳定。     

In vitro effects of propofol on blood coagulability and fibrinolysis by the use of thromboelastograph technique

BACKGROUND: To investigate the in vitro effects of propofol on blood coagulability and fibrinolysis by the use of thromboelastograph (TEG) technique. METHODS: The blood samples, obtained from 14 healthy volunteers, were divided into two groups: propofol (n = 7) and intralipid (n = 7), and 360 microliters volumes of whole blood were incubated with 2 microliters of 1% propofol and with its solvent intralipid, respectively. The incubated sample was then used for TEG measurements. RESULTS: The maximum amplitude (MA), which reflects coagulability, in the intralipid group significantly increased by about 7% and 16% compared to the control and propofol groups, respectively (P < 0.05), whereas the MA in the propofol group did not change. The fibrinolytic rate (FR) in the propofol group significantly increased by about 170% and 210% compared to the control and intralipid groups, respectively (P < 0.05), whereas the FR in the intralipid group did not change. CONCLUSIONS: Propofol, per se, has at the concentration of 55.6 micrograms.ml-1 an in vitro accelerative effect on blood fibrinolysis detected by TEG.     

异丙酚麻醉对腹部手术患者抗氧化保护作用

目的:研究异丙酚的抗氧化保护作用.方法:32例上腹部手术患者随机分为两组,治疗组静脉推注异丙酚10 mg&#8226;kg 1&#8226;h 1,对照组吸入3%安氟醚维持麻醉,分别于麻醉前,麻醉1,2,3 h抽取血样测定6 磷酸葡萄糖脱氢酶(G 6 PD)的活性、还原型谷胱甘肽(GSH)和氧化型谷胱甘肽(GSSG)的含量,并计算GSH/GSSG比值.结果:治疗组G 6 PD活性轻度升高,GSH/GSSG比值轻度降低;对照组G 6 PD活性显著升高,GSH/GSSG比值显著降低;两组比较差异有极显著性(P＜0.01).结论:异丙酚具有显著的抗氧化活性,是一种既具有麻醉效能又具有抗氧化保护作用的麻醉药物.     

丙泊酚及氯胺酮持续泵注与间断静注的静脉全麻比较

目的比较丙泊酚复合氯胺酮静脉泵注与间断静注的静脉全麻效果及安全性。方法　20例ASA　I～II级静脉全麻手术患者随机为I、II组,每组10例,I组为丙泊酚及氯胺酮分次静注组,II组为丙泊酚及氯胺酮持续静脉泵注组。两组术前3分钟静注丙珀酚0.6mg/kg,氯胺酮1mg/kg。I组术中当麻醉转浅时静注丙泊酚(0.6mg/kg)和(或)氯胺酮(1mg/kg),Ⅱ组术中以微泵泵注丙泊酚(1～3mg·kg-1·h-1),氯胺酮(2～4mg·kg-1·h-1)。记录麻醉前至手术进行1小时每隔5分钟测得的平均动脉压(MAP)、呼吸(R)及脉搏氧饱和度(SpO);整个手术过程中麻醉药用量。结果2麻醉期间I组MAP、R波动大,Ⅱ组较平稳;I组有4例SpO下降至88%～94%;Ⅱ组所有病人SpO达98%～100%以上,22两组比较差异有显著性。Ⅱ组人均氯胺酮及丙泊酚用量显著多于Ⅰ组。结论　氯胺酮及丙泊酚微泵泵注给药麻醉效果好,术中BP和R平稳,麻醉药用量少,安全性好。     

不同静脉和吸入麻醉药对罗库溴铵肌肉松弛作用的影响

目的：研究不同静脉和吸入麻醉药对罗库溴铵肌肉松弛作用的影响。方法：５０例病人分为５组，观察并比较了静脉麻醉药咪唑安定、异丙酚和吸入麻醉药（１．２ＭＡＣ）安氟醚、异氟醚和七氟醚对罗库溴铵肌肉松弛作用的影响，以及罗库溴铵对血流动力学的影响。结果：肌松作用起效时间５组间无显著差异，平均为４４．５～４９．１秒。其临床维持时间、７５％恢复时间和恢复指数三种吸入麻醉药组均显著长于两种静脉麻醉药组（Ｐ＜０．０１），而三种吸入麻醉药组间和两种静脉麻醉药组间则无显著差异。咪唑安定组和异丙酚组的肌松作用临床维持时间平均为３６．２～４１．５分钟。罗库溴铵静脉给药后血压、心率维持平稳。结论：罗库溴铵具有起效快、中等作用维持时间和血流动力学稳定的特点，但与高浓度吸入麻醉药合用可使其作用时间明显延长。     

异丙酚的剂量与镇静和呼吸抑制作用之间的关系

研究不同剂量的异丙酚的量效关系。方法:选择50例甲状腺腺瘤切除病人,随机分为5组,Ⅰ组,0.5mg/kg、Ⅱ组0.75mg/kg、Ⅲ组1.0mg/kg、Ⅳ组1.5mg/kg、V组2.0mg/kg.采用Star呼吸机监测呼吸功能指标,同时观察其神志变化,应用Probit法分析该药量效关系。结果:Ⅱ、IV、V组随着剂量增加,潮气量降低的幅度和呼吸抑制持续时间明显增加,以给药后1～3分钟潮气量减少最为明显(P<0.01),浅睡状态ED_(50)为0.98mg/kg.深睡状态ED_(50)为1.26mg/kg,呼吸抑制ED_(50)为1.1mg/kg。结论:静注0.8～1mg/kg异丙酚可以产生适用于非全麻病人的镇静、催眠作用,而对呼吸抑制的作用较小。