Tourniquet-induced ischemia-reperfusion injuries during extremity surgery at children's age: impact of anesthetic chemical structure

Abstract

Objectives

The aim of this study was to determine the relationship between the antioxidant profile of anesthetics and its relation to total antioxidant capacity (TAC) of plasma in children who underwent tourniquet-induced ischemia-reperfusion (IR) injury during extremity operations.

Methods

Children were randomized into three groups: general inhalational anesthesia with sevoflurane (group S), total intravenous anesthesia (TIVA) with propofol (group T), and regional anesthesia (group R). Venous blood samples were obtained before peripheral nerve block and induction of general anesthesia (baseline), 1 minute before tourniquet release (BTR), and 5 and 20 minutes after tourniquet release (ATR). Plasma TAC as well as antioxidant potential of propofol, thiopental, and bupivacaine were measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay.

Results

Plasma TAC in group T was increased significantly at 20 minutes ATR in comparison with basal and BTR values, and also was significantly higher in comparison with plasma TAC in groups S and R measured at the same time point. The radical scavenging activity of anesthetics in vitro indicated that only propofol possessed a significant antioxidative activity in the reaction with DPPH radical in comparison with thiopental and bupivacaine.

Discussion

These data confirm that TIVA with propofol attenuates oxidative stress related to tourniquet-induced ischaemia-reperfusion injury in children.     

BIS监测下两种快通道麻醉方式应用于鼻内镜手术的比较

目的:观察BIS指导两种快通道麻醉在鼻内镜手术中的应用及麻醉效果。方法:选择60例ASAⅠ-Ⅱ级择期行功能性鼻内镜手术(FESS)患者,随机分为七氟醚诱导维持麻醉组(VIMA组)与异丙酚全凭静脉麻醉组(TIVA组)。VIMA组:8%七氟醚,氧流量8L/min,潮气量法吸入诱导,七氟醚维持麻醉;TIVA组:异丙酚2 mg/kg诱导,异丙酚维持麻醉。两组诱导时都静脉注射瑞芬太尼1μg/kg,罗库溴铵0.6 mg/kg,监测TOF值为0、BIS60并维持5 s后行气管插管。术中静脉泵注瑞芬太尼0.2μg·kg~(-1)·min~(-1),分别调整七氟醚和异丙酚维持剂量使BIS值在气管插管后至手术结束前15 min左右保持在40~60之间,手术最后15 min保持于60~70之间。两组术后进行Steward评分,并比较两组各时点SBP、DBP、HR,拔管时间,快通道麻醉成功率和苏醒期不良反应发生率。结果:VIMA组拔管时间(11.60±2.55 min)比TIVA组的(7.13±3.26 min)明显延长(P0.05);TIVA组快通道成功率显著高于VIMA组(P0.05)。两组苏醒期不良反应的发生情况比较差异无统计学意义(P0.05)。结论:异丙酚全凭静脉麻醉用于鼻内镜手术拔管时间比七氟醚诱导维持麻醉短,快通道麻醉效果更好。     

米库氯铵用于全麻手术40 例的临床分析

目的:观察米库氯铵分别复合七氟醚、丙泊酚用于全麻手术的肌松效果和安全性,以及对米库氯铵剂量的影响。方法:选择妇科手术患者40例,随机分为七氟醚组和丙泊酚组。诱导期单次静注米库氯铵,肌松开始恢复时开始泵注,手术结束前约20 min停药。记录诱导起效时间、无反应期,停止泵注米库氯铵后TOF比值恢复至25%、50%、75%、90%时间、恢复指数,维持期米库氯铵平均泵注速度、平均追加次数。结果:S组有2例、P组有1例出现轻度皮肤潮红,P组有1例插管时出现轻度呛咳,血压、心率未见明显异常,插管条件均满意。两组诱导起效时间、无反应期、恢复指数无统计学差异,停药后TOF比值恢复至25%、50%、75%、90%时间S组长于P组,差异有统计学意义。S组维持期米库氯铵平均泵注速度、平均追加次数小于P组,差异有统计学意义。结论:米库氯铵用于全麻诱导及维持,肌松满意,恢复迅速,安全性值得肯定。与丙泊酚相比,七氟醚对米库氯铵的需要量大约可以减少20%~30%,丙泊酚对米库氯铵剂量的具体影响有待进一步研究。     

Propofol Pharmacokinetics and Estimation of Fetal Propofol Exposure during Mid-Gestational Fetal Surgery: A Maternal-Fetal Sheep Model

Background

Measuring fetal drug concentrations is extremely difficult in humans. We conducted a study in pregnant sheep to simultaneously describe maternal and fetal concentrations of propofol, a common intravenous anesthetic agent used in humans. Compared to inhalational anesthesia, propofol supplemented anesthesia lowered the dose of desflurane required to provide adequate uterine relaxation during open fetal surgery. This resulted in better intraoperative fetal cardiac outcome. This study describes maternal and fetal propofol pharmacokinetics (PK) using a chronically instrumented maternal-fetal sheep model.

Methods

Fetal and maternal blood samples were simultaneously collected from eight mid-gestational pregnant ewes during general anesthesia with propofol, remifentanil and desflurane. Nonlinear mixed-effects modeling was performed by using NONMEM software. Total body weight, gestational age and hemodynamic parameters were tested in the covariate analysis. The final model was validated by bootstrapping and visual predictive check.

Results

A total of 160 propofol samples were collected. A 2-compartment maternal PK model with a third fetal compartment appropriately described the data. Mean population parameter estimates for maternal propofol clearance and central volume of distribution were 4.17 L/min and 37.7 L, respectively, in a typical ewe with a median heart rate of 135 beats/min. Increase in maternal heart rate significantly correlated with increase in propofol clearance. The estimated population maternal-fetal inter-compartment clearance was 0.0138 L/min and the volume of distribution of propofol in the fetus was 0.144 L. Fetal propofol clearance was found to be almost negligible compared to maternal clearance and could not be robustly estimated.

Conclusions

For the first time, a maternal-fetal PK model of propofol in pregnant ewes was successfully developed. This study narrows the gap in our knowledge in maternal-fetal PK model in human. Our study confirms that maternal heart rate has an important influence on the pharmacokinetics of propofol during pregnancy. Much lower propofol concentration in the fetus compared to maternal concentrations explain limited placental transfer in in-vivo paired model, and less direct fetal cardiac depression we observed earlier with propofol supplemented inhalational anesthesia compared to higher dose inhalational anesthesia in humans and sheep.     

Plasma proinflammatory cytokine response to surgical stress in elderly patients

We investigated the change of plasma cytokines concentrations in elderly patients during lower abdominal surgery. Plasma interleukin (IL-)6 concentrations (68.0+/-15.4 and 36.1+/-20.7 pg/ml) in elderly patients at 24 h and at 3 days after surgery were significantly higher than those (35.1+/-21.5 and 18.6+/-10.6 pg/ml) of young adults. Plasma IL-6 concentrations (92.3+/- 31.9 pg/ml) in elderly patients anesthetized with propofol and fentanyl were significantly higher at the end of the operation than that (57.9+/-36.7 pg/ml) of elderly patients anesthetized with sevoflurane and fentanyl. In conclusion, elderly patients have an increased and delayed IL-6 response to surgical trauma compared with young adults. Plasma IL-6 production after surgical trauma in elderly patients with total intravenous anesthesia with propofol was significantly higher than that in elderly patients with sevoflurane anesthesia.     

右美托咪定复合丙泊酚全麻在腰椎管减压、椎弓根钉内固定植骨、融合术中的应用

目的:观察右美托咪定复合丙泊酚全麻在腰椎管减压、椎弓根钉内固定植骨融合术中的应用价值。方法:将2015年7月至2019年8月于我院手术治疗84例腰椎退行性疾病患者按随机数字表法分为观察组和对照组,每组42例。观察组于麻醉诱导前静脉泵入0.5μg/kg右美托咪定并在术中以0.2μg/kg·h麻醉维持,对照组于麻醉诱导前静脉泵入生理盐水。对比两组麻醉诱导前(T0)、诱导后(T1)、插管后1 min(T2)和5 min(T3)、拔管1 min(T4)和5 min(T5)的心率(HR)、收缩压(SBP)及舒张压(DBP)的数值,同时记录患者的手术时间、苏醒时间、瑞芬太尼用量及12 h内吗啡用量。比较各时间点VAS评分及不良反应的发生率。结果:与T0比较,两组患者T1时HR、SBP、DBP均显著降低(P<0.05),与T1比较,两组患者T2、T3和T4时HR、SBP、DBP均显著升高(P<0.05),观察组在T3、T4和T5时HR、SBP、DBP均显著降低(P<0.05)。观察组患者各时间点VAS评分及瑞芬太尼用量和24 h吗啡用量均显著低于对照组(P<0.05),观察组患者不良反应发生率显著低于对照组(P<0.05)。结论:右美托咪定复合丙泊酚全麻能够维持术中血液动力学稳定,减少术中麻醉药物和术后镇痛药物用量,改善术后镇痛效果,且不良反应少。     

雷米芬太尼联合丙泊酚对妇科腹腔镜手术患者的血流动力学及麻醉苏醒的影响

目的:探讨雷米芬太尼联合丙泊酚对妇科腹腔镜手术患者的血流动力学及麻醉苏醒的影响。方法:将116例拟行妇科腹腔镜手术患者随机分为观察组和对照组,观察组给予雷米芬太尼联合丙泊酚全凭静脉麻醉,对照组给予芬太尼联合丙泊酚全凭静脉麻醉。比较两组术中平均动脉压(MAP)、心率(HR)、血气分析指标、患者麻醉后睁眼时间、拔管时间及答问切题时间。结果:麻醉诱导后两组平均动脉压(MAP)及心率(HR)均显著下降(P0.05);观察组插管即刻及插管后2 min MAP及HR显著低于对照组(P0.05);观察组麻醉后睁眼时间、拔管时间、答问切题时间显著早于对照组(P0.05);与气腹前相比,气腹10 min、20 min及60min的PaCO2均升高(P0.05),两组各时点其他血气分析指标比较无显著差别(P0.05)。结论:妇科腹腔镜手术给予雷米芬太尼联合丙泊酚全凭静脉麻醉,可显著减轻插管应激心血管反应,保持血流动力学稳定,效果优于芬太尼联合丙泊酚麻醉。     

肌间沟臂丛神经阻滞复合静脉全麻对肩关节镜手术患者麻醉效果、MAP、HR以及血清Cor、NE的影响

目的:分析B超指引下实施肌间沟臂丛神经阻滞复合静脉全麻对肩关节镜手术患者麻醉效果、心率(HR)、平均动脉压(MAP)以及血清皮质醇(Cor)、去甲肾上腺素(NE)水平的影响。方法:选择本院2016年3月至2019年12月收治的80例肩关节镜手术患者,以随机数字表法作为分组原则(每组样本容量40例),对照组实施单纯全凭静脉麻醉,实验组实施B超指引下肌间沟臂丛神经阻滞复合静脉全麻,对比两组不同时点MAP、HR、血清Cor、NE水平以及瑞芬太尼、尼群地平(NIT)、丙泊酚使用剂量,并对比两组并发症发生情况。结果:实验组T1-4时点MAP、HR、血清Cor、NE水平均明显低于对照组(P0.05),瑞芬太尼、NIT以及丙泊酚使用剂量实验组均明显较对照组减少(P0.05);两组并发症发生率比较未见统计学差异(P0.05)。结论:B超指引下肌间沟臂丛神经阻滞复合静脉全麻应用于肩关节镜手术中可抑制患者体内应激物质释放,将MAP及HR维持在稳定范围内,极大地减少了麻醉药物、NIT使用剂量,麻醉效果理想、确切。     

Mass-spectrometry analysis of disflurane,propofol, and fentanyl in plasma and cerebrospinal fluid

Concentrations of anesthetic agents were measured in blood plasma and cerebrospinal fluid using mass spectrometry with a membrane interface. Sampling of biological fluids was performed during balanced inhalational (disflurane and fentanyl) anesthesia and total intravenous (propofol and fentanyl) anesthesia. A rapid test method for the concentration measurement of organic molecules in biological fluids is described. This method does not require long-term sample processing before injecting the sample into the mass spectrometer interface. The pervaporation properties (uptake, diffusion, and evaporation) of anesthetic agents from biological fluids in a silicone membrane were used in the mass spectrometry interface. We report on the possibility of using a mass spectrometer with a membrane interface for the measurement of the absolute concentration of anesthetic agents in blood plasma for study of the properties of the blood–brain barrier.     

Ultrasound-Assisted Thoracic Paravertebral Block Reduces Intraoperative Opioid Requirement and Improves Analgesia after Breast Cancer Surgery: A Randomized,Controlled, Single-Center Trial

Objectives

The contribution of ultrasound-assisted thoracic paravertebral block to postoperative analgesia remains unclear. We compared the effect of a combination of ultrasound assisted-thoracic paravertebral block and propofol general anesthesia with opioid and sevoflurane general anesthesia on volatile anesthetic, propofol and opioid consumption, and postoperative pain in patients having breast cancer surgery.

Methods

Patients undergoing breast cancer surgery were randomly assigned to ultrasound-assisted paravertebral block with propofol general anesthesia (PPA group, n = 121) or fentanyl with sevoflurane general anesthesia (GA group, n = 126). Volatile anesthetic, propofol and opioid consumption, and postoperative pain intensity were compared between the groups using noninferiority and superiority tests.

Results

Patients in the PPA group required less sevoflurane than those in the GA group (median [interquartile range] of 0 [0, 0] vs. 0.4 [0.3, 0.6] minimum alveolar concentration [MAC]-hours), less intraoperative fentanyl requirements (100 [50, 100] vs. 250 [200, 300]μg,), less intense postoperative pain (median visual analog scale score 2 [1, 3.5] vs. 3 [2, 4.5]), but more propofol (median 529 [424, 672] vs. 100 [100, 130] mg). Noninferiority was detected for all four outcomes; one-tailed superiority tests for each outcome were highly significant at P<0.001 in the expected directions.

Conclusions

The combination of propofol anesthesia with ultrasound-assisted paravertebral block reduces intraoperative volatile anesthetic and opioid requirements, and results in less post operative pain in patients undergoing breast cancer surgery.

Trial Registration

ClinicalTrial.gov NCT00418457     

Relationship of bispectral index values, haemodynamic changes and recovery times during sevoflurane or propofol anaesthesia in rabbits

The aim of this study was to determine and compare the degree of hypnosis achieved during propofol or sevoflurane anaesthesia in rabbits using bispectral index (BIS), and to evaluate its usefulness as a predictor of both haemodynamic changes during anaesthesia and recovery times. Twenty adult male New Zealand White rabbits, average weight 4.4 +/- 0.4 kg, were used for this study. Animals were randomly allocated to one of two groups with 10 rabbits/group. An electroencephalographic recording was obtained from each conscious rabbit prior to drug administration. All animals received buprenorphine as a preanaesthetic medication (0.05 mg/kg, intravenous [i.v.]). Anaesthesia was induced with propofol (8 mg/kg, i.v.) in all animals; 10 rabbits were maintained with sevoflurane via inhalation (1 minimum alveolar concentration--end-tidal sevoflurane concentration of 3.7%--at a fresh gas flow rate of 3 L/min; group I), and 10 were maintained with i.v. propofol (0.6 mg/kg/min; group II). The rabbits were orotracheally intubated and spontaneous ventilation was maintained throughout the study (100% oxygen). After abdominal surgery through a ventral midline laparotomy, rabbits were allowed to recover from anaesthesia. Cardiovascular variables and BIS values were recorded at intervals throughout the procedure, as was the duration of recovery from anaesthesia. In both groups, mean BIS values were significantly decreased immediately after induction, compared with baseline values obtained during consciousness. Anaesthetic depth (evaluated by clinical observation) was similar in both groups; however, group II rabbits had significantly higher (P<0.001) BIS values from 30 s before incision until anaesthesia was discontinued. There was no significant difference in BIS recorded 1 and 5 min after incision as compared with values obtained 30 s before incision in either group. During sevoflurane or propofol administration, correlations were found between BIS values and mean arterial blood pressure (MABP), and between BIS values and heart rate (HR). Mean BIS values at discontinuation of administration of the anaesthetic agent were greater in group II (69.1 +/- 6.0) than in group I (49.3 +/- 2.2). However, recovery from anaesthesia was significantly longer in group II (38.4 +/- 7.2 min) than in group I (11.5 +/- 2.5 min). In conclusion, BIS can be used to differentiate between conscious and unconscious states during anaesthesia in rabbits. BIS values derived from an electroencephalogram at the end of anaesthesia were not useful for predicting the speed of anaesthetic recovery in sevoflurane or propofol-anaesthetized rabbits undergoing abdominal surgery. Despite the correlation found between BIS and haemodynamic parameters, its usefulness as a predictor of clinically important changes in arterial blood pressure and HR in anaesthetized rabbits was limited.     

The effect of preoperative suggestions on perioperative dreams and dream recalls after administration of different general anesthetic combinations: a randomized trial in maxillofacial surgery

Background

Images evoked immediately before the induction of anesthesia with the help of suggestions may influence dreaming during anesthesia.The aim of the study was to assess the incidence of evoked dreams and dream recalls by employing suggestions before induction of anesthesia while administering different general anesthetic combinations.

Methods

This is a single center, prospective randomized including 270 adult patients scheduled for maxillofacial surgical interventions. Patients were assigned to control, suggestion and dreamfilm groups according to the psychological method used. According to the anesthetic protocol there were also three subgroups: etomidate & sevoflurane, propofol & sevoflurane, propofol & propofol groups. Primary outcome measure was the incidence of postoperative dreams in the non-intervention group and in the three groups receiving different psychological interventions. Secondary endpoint was to test the effect of perioperative suggestions and dreamfilm-formation training on the occurrance of dreams and recallable dreams in different general anesthesiological techniques.

Results

Dream incidence rates measured in the control group did not differ significantly (etomidate & sevoflurane: 40%, propofol & sevoflurane: 26%, propofol & propofol: 39%). A significant increase could be observed in the incidence rate of dreams between the control and suggestion groups in the propofol & sevoflurane (26%-52%) group (p = 0.023). There was a significant difference in the incidence of dreams between the control and dreamfilm subgroup in the propofol & sevoflurane (26% vs. 57%), and in the propofol & propofol group (39% vs.70%) (p = 0.010, and p = 0.009, respectively). Similar to this, there was a significant difference in dream incidence between the dreamfilm and the suggestion subgroups (44% vs. 70%) in the propofol & propofol group (p = 0.019). Propofol as an induction agent contributed most to dream formation and recalls (χ2-test p value: 0.005). The content of images and dreams evoked using suggestions showed great agreement using all three anesthetic protocols.

Conclusion

The psychological method influenced dreaming during anesthesia. The increase of the incidence rate of dreams was dependent on the anesthetic agent used, especially the induction agent.The study was registered in ClinicalTrials.gov. Identifier: {"type":"clinical-trial","attrs":{"text":"NCT01839201","term_id":"NCT01839201"}}NCT01839201.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2253-15-11) contains supplementary material, which is available to authorized users.     

Effects of spinal or general anesthesia on F₂-isoprostanes and isofurans during ischemia/reperfusion of the leg in patients undergoing knee replacement surgery

General and spinal anesthesia are used extensively in orthopedic surgery. However, these methods of anesthesia may result in different amounts of oxygen being delivered to the patient. Ischemia/reperfusion injury after release of the tourniquet initiates free radical-mediated oxidative stress. F₂-isoprostanes are reliable markers of in vivo lipid peroxidation. However, under conditions of high oxygen tension, isofurans are formed. We aimed to compare plasma isofurans and F₂-isoprostanes in spinal versus general anesthesia in patients undergoing knee-replacement surgery in a randomized, blinded study. Thirty-nine patients were randomized to spinal (SA; n = 19) or general anesthesia (GA; n = 20). Blood was collected before anesthesia, and a tourniquet was then applied to the limb during surgery. After release of the tourniquet, blood samples were collected at 30 min, 2 h, and 24 h for measurement of plasma F₂-isoprostanes and isofurans by gas chromatography–mass spectrometry. The two groups were comparable in age and body mass index. Plasma F₂-isoprostanes were significantly lower in the GA patients compared with the SA patients (p = 0.045). In contrast, the GA patients had significantly elevated plasma isofurans (p = 0.032). Increased isofurans during GA compared with SA are likely to reflect increased oxidative stress due to elevated oxygen concentrations during GA. Further studies are required to assess the implications of these findings on perioperative outcomes.     

Integrated analysis of protein and glucose metabolism during surgery: effects of anesthesia.

The aim of this study was to assess dynamic changes in protein and glucose metabolism during surgery. Twelve patients undergoing colorectal surgery received either intravenous propofol anesthesia (n = 6) or inhalational anesthesia with desflurane (n = 6). Pre- and intraoperative protein and glucose kinetics were analyzed by an isotope dilution technique using L-[1-(13)C]leucine and [6,6-(2)H(2)]glucose. Plasma concentrations of glucose, lactate, free fatty acids, insulin, glucagon, and cortisol were measured before and after 2 h of surgery. The rates of appearance of leucine and glucose, leucine oxidation, protein synthesis, and glucose clearance decreased during surgery, independent of the type of anesthesia (P < 0.05). A correlation between the rate of appearance of leucine and glucose was observed (r = 0.755, P < 0.001). Intraoperative plasma cortisol and glucose concentrations increased (P < 0.05), whereas plasma concentrations of lactate, free fatty acids, insulin, and glucagon did not change. Surgery causes a depression of whole body protein and glucose metabolism, independent of the anesthetic technique. There is a correlation between perioperative glucose production and protein breakdown.     

The effect of propofol and fentanyl as compared with sevoflurane on postoperative vomiting in children after adenotonsillectomy

Postoperative vomiting (PV) after adenotonsillectomy in children is a common problem with an incidence as high as 40-80%. Only few studies in the recent literature compared the effect of different anesthetic techniques concerning PV in children. The aim of this study was to compare the incidence of PV in two groups of children who underwent two different general anesthesia techniques in order to determine what type of anesthetic technique is more related to less PV. The clinical trial included 50 children (physical status ASA I, 3-12 years old) divided into 2 groups and monitored for PV 24 hours following the surgery. Group one (G1) consisted of 25 children who underwent general anesthesia with gas mixture 60% nitrous oxide and 40% oxygen and anesthetic propofol, opioid fentanyl and muscle relaxant vecuronium intravenously and group two (G2) included 25 children to whom volatile anesthesia with sevoflurane in the same gas mixture was given. Demographic characteristics (gender, age, weight, history of motion sickness and earlier PV) as well as surgical data (length of surgery and anesthesia, intraoperative blood loss) were recorded. There were no significant differences considering demographic characteristics and surgical data between the investigated groups. The incidence of PV was relatively low 3 children (12%) in G1 group and 5 children (20%) in G2 group. Statistically there was no significant difference between the groups regarding the incidence of PV and both anesthetic techniques can be used equally safe regarded to PV.     

异丙酚复合咪达唑仑与舒芬太尼在老年无痛结肠镜检查的临床观察

目的:观察异丙酚复合咪达唑仑与舒芬太尼在老年无痛结肠镜检查的麻醉效果。方法:将2010年5月至2011年9月期间共126例患者随机分成3组,每组42例,即异丙酚组(A组),舒芬太尼+异丙酚组(B组),咪达唑仑+舒芬太尼+异丙酚组(C组)。比较各组用药前、术中及苏醒后的SBP、DBP、HR、SPO2,同时比较异丙酚用药总量、苏醒时间和留院观察时间。结果:三组患者在用药后5 min SBP、DBP、HR、SpO2均出现一定程度的下降,B组与C组SBP、DBP的组内比较有统计学差异(P0.05);A组HR组内比较有统计学意义(P0.05);三组患者的SBP、DBP、HR比较有统计学意义(P0.05);三组患者的异丙酚用量,恢复时间有统计学差异(P0.05);术后不良反应的比较无统计学意义(P0.05)。结论:异丙酚复合咪达唑仑与舒芬太尼是一种安全可行的无痛结肠镜麻醉方法,值得推广。     

Intravenous propofol,ketamine (ketofol) and rocuronium after sevoflurane induction provides long lasting anesthesia in ventilated rats

Rats are commonly used animals for laboratory experiments and many experiments require general anesthesia. However, the lack of published and reproducible intravenous anesthesia protocols for rats results in unnecessary animal use to establish new anesthesia techniques across institutions. We therefore developed an anesthesia protocol with propofol, ketamine, and rocuronium for mechanically ventilated rats, and evaluated vital parameters and plasma concentrations. 15 male Sprague-Dawley rats underwent inhalation induction with sevoflurane and tracheal, venous and arterial cannulation. After established venous access, sevoflurane was substituted by propofol and ketamine (ketofol). Rocuronium was added under mechanical ventilation for 7 h. Drug dosages were stepwise reduced to prevent accumulation. All animals survived the observation period and showed adequate depth of anesthesia. Mean arterial pressure and heart rate remained within normal ranges. Median propofol plasma concentrations remained stable: 1, 4, 7 h: 2.0 (interquartile range (IQR): 1.8–2.2), 2.1 (1.8–2.2), 1.8 (1.6–2.1) µg/ml, whereas median ketamine concentrations slightly differed after 7 h compared to 1 h: 1, 4, 7 h: 3.7 (IQR: 3.5–4.5), 3.8 (3.3–4.1), 3.8 (3.0–4.1) µg/ml. Median rocuronium plasma concentrations were lower after 4 and 7 h compared to 1 h: 1, 4, 7 h: 3.9 (IQR: 3.5–4.9), 3.2 (2.7–3.3), 3.0 (2.4–3.4) µg/ml. Our anesthesia protocol provides stable and reliable anesthesia in mechanically ventilated rats for several hours.     

丙泊酚联合七氟烷复合麻醉对小儿麻醉苏醒期躁动评分的影响

目的:探讨丙泊酚联合七氟烷对小儿麻醉苏醒期躁动的临床效果。方法:选择2013年8月-2015年8月在我院接受手术治疗的患儿53例,根据麻醉方法不同,将研究对象分为丙泊酚组(17例)、七氟烷组(19组)和联合组(17例),分别给予丙泊酚,七氟烷以及丙泊酚联合七氟烷进行麻醉并维持。观察并比较各组患儿的手术时间、麻醉时间、清醒时间、躁动发生率以及苏醒期躁动评分。结果:三组患儿的手术时间和麻醉苏醒时间比较,差异均无统计学意义(P0.05);联合组患儿躁动发生率及躁动评分均低于七氟烷组和丙泊酚组,差异具有统计学意义(P0.05);三组患儿恶心、呕吐等不良反应的发生率比较,差异无统计学意义(P0.05)。结论:丙泊酚联合七氟烷可显著改善小儿麻醉苏醒期躁动情况,临床效果显著。     

全凭静脉麻醉对腔镜下甲状腺手术的苏醒躁动及术后镇痛效果的影响

目的:探讨全凭静脉麻醉(TIVA)对腔镜下甲状腺手术的苏醒躁动及术后镇痛效果的影响。方法:将74例接受腔镜下甲状腺手术的患者随机分为TIVA组与静吸复合麻醉(VICA)组,每组各37例。比较两组诱导麻醉前(T0)、切皮后1 min(T1)、手术开始后30 min(T3)、手术结束时(T3)及术后30 min(T4)血糖(GLU)、血清皮质醇(COR)、白介素(IL-6)水平的变化、麻醉药物用量、术后自主呼吸恢复时间、苏醒时间、拔管时间、苏醒期躁动及术后镇痛效果。结果:T1时刻,两组GLU、COR、IL-6水平均呈现出不同程度升高,而TIVA组T1~T4时刻各指标均较VICA组明显降低(P0.05)。与VICA组比较,TIVA组丙泊酚的术中使用量显著减少,术后自主呼吸恢复时间、苏醒时间及拔管时间均显著缩短(P0.05),苏醒期躁动的发生率及躁动程度均较VICA组明显降低(P0.05),术后12、24 h切口疼痛的VAS评分均明显高于VICA组(P0.05)。结论:TIVA应用于腔镜下甲状腺手术可减少机体的应激反应和全麻药剂量,改善苏醒期质量,但应根据患者的疼痛感受采取必要的镇痛措施。     

术中不同速率输注右美托咪定在全凭静脉麻醉中的量效关系研究

目的：以脑电双频指数（bispectral index,BIS）作为麻醉镇静程度指标,探讨不同速率输注右美托咪定（dexmedetomidine,DEX）对全凭静脉麻醉中丙泊酚用量,术中重要时点血液动力学及麻醉恢复质量的影响。方法：选择拟于全麻下行妇科腹腔镜手术的患者60例（ASAI～II级）,根据DEX输注速率不同随机分为四组,即D1、D2、D3和D4组,每组15例,麻醉诱导前四组均给予负荷剂量DEX0．5μg·kg-1,10min输注完毕,继而四组分别以0．2、0．4、0．6和0．8μg·kg^-1·h^-1输注速度持续输注至冲洗腹腔。四组麻醉诱导方法相同,术中以BIS作为麻醉深度指标,根据BIS值调节丙泊酚血浆靶浓度维持麻醉。记录入室用药前（T0）、DEX负荷量输注后（T1）、气腹即刻（T2）、气腹后5min（T3）、气腹后30min（T4）、解除气腹后5min（T5）、拔喉罩即刻（T6）、拔喉罩后1min（T7）时收缩压（SBP）、舒张压（DBP）、心率（HR）、丙泊酚平均用量、苏醒时间、拔喉罩时间、拔喉罩后15rainOAA／s评分、术中及术后24小时内不良反应的发生情况。结果：①D2、D3、D4组丙泊酚平均用量较D1组明显减少（P〈0．05）,D3、D4组丙泊酚平均用量较D：组明显减少（P〈0．05）。D3、D4组间差异无统计学意义（P〉0．05）。②与T0比较,Tl～T2时四组SBP、DBP、HR降低（P〈0．05）,T3～T4时D3、D4组SBP、DBP、HR降低（P〈0．05）,D1、D2组SBP、DBP无明显变化（P〉0．05）,T5～T7时四组SBP、DBP、HR降低（P〈0．05）;D3、D4组在T3～T4时SBP、DBP较D1、D2组明显降低（P〈O．05）,D1、D2两组间差异无统计学意义（P〉0．05）,D3、D4两组间差异无统计学意义（P〉0．05）。③D4组苏醒时间、拔喉罩时间、较Dlq组明显延长（P〈0．05）,D4组OAA／s评分较D1-3组明显降低（P〈0．05）。④D4组使用阿托品次数较D1-3组明显增多（P〈0．05）,四组术中使用麻黄碱次数和术后24小时内恶心、呕吐、寒战差异无统计学差异（P〉0．05）。结论：在妇科腹腔镜手术中,DEX作为全身麻醉辅助用药,负荷剂量0．5μg·kg-1,术中持续输注速率0．4μg·kg-1·h-1可以有效降低丙泊酚用量,使围手术期的血流动力学保持平稳,不延长苏醒时间和拔喉罩时间,且不良反应更少,值得临床推广应用。