七氟醚抑制帕金森病患者切皮时肾上腺素能反应的最低肺泡有效浓度

目的探讨七氟醚抑制帕金森病(PD)患者切皮时肾上腺素能反应的最低肺泡有效浓度(MAC_(BAR))。方法选择2019年10月至2021年3月择期行脑深部刺激器植入术患者21例,男10例,女11例,年龄40～64岁,BMI 18～30 kg/m~2,ASAⅠ—Ⅲ级。采用吸入8%七氟醚进行麻醉诱导,喉罩置入后调整呼气末七氟醚浓度(C_(ET)Sev)至预设水平。采用序贯法测定七氟醚MAC_(BAR)。第1例患者C_(ET)Sev调整至3%,稳定后15 min切开锁骨下皮肤。将切皮前3、1 min HR和MAP的平均值记录为基础值,将切皮后1、3 min HR和MAP的平均值记录为变化值,若HR或MAP升高幅度超过基础值的20%则定义为肾上腺素能反应阳性。若切皮时肾上腺素能反应为阳性,下一例采用高一级浓度,否则采用低一级浓度,浓度梯度为0.2%。当出现7个"阳性反应-阴性反应"的转折点时停止试验。采用概率回归法计算七氟醚MAC_(BAR)及其95%可信区间(CI)。结果肾上腺素能反应阳性的患者MAP变化值明显高于肾上腺素能反应阴性的患者(P0.05)。通过概率回归法算得PD患者切皮时七氟醚MAC_(BAR)为2.11%(95%CI 1.94%～2.27%)。结论七氟醚抑制帕金森病患者切皮时肾上腺素能反应的最低肺泡有效浓度为2.11%(95%CI 1.94%～2.27%)。     

早产儿平稳气管插管时七氟醚的最低肺泡有效浓度

目的探讨早产儿气管插管无体动反应时的七氟醚最低肺泡有效浓度(MACEI)。方法选择择期吸入全麻下行眼科手术的早产儿27例,矫正胎龄37周,ASAⅠ或Ⅱ级。吸入6%七氟醚进行全麻诱导,至患儿意识消失后,将呼气末七氟醚浓度调整至预定值,维持15min,然后行气管插管。根据序贯法进行研究,初始呼气末七氟醚浓度为3.0%,如气管插管时发生体动反应,下一例升高一个浓度梯度,如气管插管时未发生体动反应,下一例降低一个浓度梯度,相邻浓度梯度为0.2%。将无体动反应时呼气末七氟醚浓度到体动反应时呼气末七氟醚浓度的中点设为一个平衡点,计算所有平衡点七氟醚浓度的平均值即为MACEI。结果患儿气管插管无体动反应的七氟醚MACEI为2.55%±0.20%,MAC95是2.81%(95%CI 2.67%~3.58%)。结论早产儿平稳气管插管的七氟醚MACEI为2.55%,低于足月产儿的参考值。     

新辅助化疗后胃癌手术七氟醚最低肺泡有效浓度的测定

目的确定接受新辅助化疗后1个月行胃癌根治术的患者全凭吸入麻醉时外科切皮无体动反应的七氟醚最低肺泡有效浓度(minimum alveolar concentration,MAC)。方法择期行胃癌根治术患者25例,男14例,女11例,年龄30~50岁,ASAⅠ或Ⅱ级,于手术1个月前结束2个周期的奥沙利铂复合替吉奥化疗(1个化疗周期为14 d)。吸入6%七氟醚全麻诱导,至患者意识消失行气管插管术后,将呼气末七氟醚浓度调整至预定值,维持15 min不变,然后外科切皮。根据Dixon上下法进行试验,初始呼气末七氟醚浓度为2.2%,切皮时发生体动反应,下一例升高一个浓度梯度,切皮时未发生体动反应,下一例降低一个浓度梯度,相邻浓度梯度为0.2%。采用Probit分析计算出七氟醚的MAC和95%CI。结果本研究中进行外科切皮操作时,患者的体动反应表现为肢体轻微活动,所有患者均未发生身体大幅扭动、睁眼或术中知晓等严重并发症。有11例(44%)患者发生体动。接受新辅助化疗的胃癌患者在外科切皮时无体动反应的七氟醚MAC值为1.52%,95%CI为1.37%~1.65%。结论接受新辅助化疗的胃癌患者切皮无体动反应的七氟醚的MAC值为1.52%。     

犬静脉注射乳化异氟醚最低肺泡有效浓度的研究

目的测定犬静脉注射乳化异氟醚的最低肺泡有效浓度(MAC静脉),并与吸入异氟醚麻醉时的最低肺泡有效浓度(MAC吸入)进行比较。方法将40只杂种犬平均分成静脉和吸入麻醉两组。应用序贯法和自身交叉法同时测定犬的MAC值。结果静脉组序贯法所测得的MAC静脉(0.94±0.10)%,与自身交叉法所测得的前6个交叉点的MAC静脉(0.89±0.14)%或全部交叉点的MAC静脉(0.93±0.13)%之间差异均无显著意义(P>0.05)。吸入组序贯法所测得的MAC吸入(1.29±0.10)%,与自身交叉法所测得的前6个交叉点的MAC吸入(1.24±0.06)%或全部交叉点的MAC吸入(1.33±0.09)%之间差异亦无显著意义(P>0.05)。但两组间比较MAC静脉均小于MAC吸入,差异有显著意义(P<0.05)。结论乳化异氟醚静脉麻醉时的MAC静脉明显小于吸入异氟醚麻醉时的MAC吸入,序贯法和自身交叉法对MAC的测定结果无明显影响。     

切剥儿童腭瓣时异氟醚最低肺泡有效浓度的测定

自Ｓａｉｄｍａｎ和Ｅｇｅｒ[1] 测定阻止 5 0 %病人对切皮刺激产生体动反应肺泡最低有效浓度 (ＭＡＣＳＩ)以来 ,临床麻醉中气管插管、剥切肋骨和清醒等的ＭＡＣ亦有较多报道[2 ] 。为探讨儿童腭裂术中适宜的麻醉深度 ,作者进行了切剥腭瓣所需ＭＡＣ(ＭＡＣＰＥ)的测定 ,现介绍如下。资料与方法一般资料　择期行Ⅱ°～Ⅲ°腭裂修复术患儿 30例 ,年龄 4～ 12岁 ,体重 14～ 32ｋｇ ,ＡＳＡⅠ～Ⅱ级 ,心肺及肝肾功能检查无异常 ,近 1周内未服用镇痛类药物。麻醉方法及监测　术前半小时肌注阿托品 0 0 1ｍｇ/ｋｇ ,入室后监测心电图、血压、血…     

安氟醚阻断小儿交感反应的最低肺泡有效浓度

目的　测定两个不同年龄段的小儿安氟醚的最低肺泡有效浓度 ,即MACbar。方法　2 8例ASAⅠ～Ⅱ级择期行腹部手术的小儿 ,分为三组 :大于 1岁单用安氟醚组 ;大于 1岁加用芬太尼组 ;6～ 12月龄单用安氟醚组。用丙泊酚 3mg/kg、维库溴铵 0 15mg/kg诱导 ,吸入安氟醚和氧气维持麻醉。大于 1岁加用芬太尼组 ,在切皮前 5min ,静脉加芬太尼 3μg/kg。各组MACbar的测定采用“上下法” ,起始浓度为 1MAC。前一病人的反应若为阳性 ,后一病人的肺泡浓度则上调0 3MAC ;若为阴性则下降 0 3MAC。切皮后 5min内的血压或心率的升高≥切皮前即刻的 15 %为交感神经反应阳性 ,<15 %则为阴性。结果　大于 1岁小儿安氟醚的MACbar值为 (3 2± 0 5 ) % ,95 %可信区间为 (2 8～ 3 6 ) % ;6～ 12月龄者为 (3 4± 0 5 ) % ,95 %可信区间为 (3 0～ 3 8) % ;3μg/kg芬太尼可以使大于 1岁小儿安氟醚的MACbar值降为 (2 2± 0 4 ) % ,95 %可信区间为 (1 8～2 5 ) %。结论　大于 6个月的小儿 ,安氟醚的肺泡浓度维持 3 3%左右 ,即约 1 5MAC ,可以阻断5 0 %的病人在切皮时的交感神经反应 ;3μg/kg芬太尼可以使其降低到约 1MAC。     

股神经阻滞对七氟醚抑制膝关节镜置入时肾上腺素能反应的最低肺泡有效浓度的影响

目的探讨超声引导下股神经阻滞对膝关节镜手术患者膝关节镜置入时七氟醚抑制肾上腺素能反应的最低肺泡有效浓度(MAC_(BAR))的影响。方法选择2019年5—8月拟行择期单侧膝关节镜手术患者36例,男19例,女17例,年龄18～64岁,ASAⅠ或Ⅱ级。采用随机数字表法将患者分为两组:阻滞组和对照组。阻滞组全麻诱导前于超声引导下行患侧股神经阻滞,采用针刺法评估VAS疼痛评分判断阻滞效果;对照组仅行全麻。两组全麻方法相同。采用序贯法测定七氟醚MAC_(BAR)。采用ELISA法测定膝关节镜置入前3 min、置入后3 min血浆肾上腺素及去甲肾上腺素浓度。记录拔管时间、拔管时VAS疼痛评分。结果阻滞组和对照组的MAC_(BAR)分别为2.73%(95%CI 2.65%～2.82%)和3.50%(95%CI 3.32%～3.68%)。与对照组比较,阻滞组七氟醚MAC_(BAR)明显降低(P0.05),拔管时间明显缩短(P0.05),VAS疼痛评分明显降低(P0.05)。阻滞组膝关节镜置入后血浆肾上腺素和去甲肾上腺素浓度分别为(784.82±348.52)pg/ml和(882.76±430.50)pg/ml,对照组膝关节镜置入后血浆肾上腺素和去甲肾上腺素浓度分别为(721.84±314.32)pg/ml和(806.69±467.88)pg/ml,两组差异无统计学意义。结论超声引导下股神经阻滞可明显降低膝关节镜手术患者膝关节镜置入时七氟醚MAC_(BAR),缩短拔管时间,有利于术后镇痛。当50%患者肾上腺素能反应被抑制时,血浆肾上腺素和去甲肾上腺素浓度变化不受股神经阻滞的影响。     

65岁以上老年人地氟醚肺泡气最低有效浓度测定

目的　测定我国 6 5岁以上老年人地氟醚的肺泡气最低有效浓度 (MAC)。方法　选择ASAⅠ～Ⅱ级择期手术的 6 5岁以上患者 ,术前检查排除肝、肾、脑及心脏系统疾病 ,无酗酒史 ,无术前用药。入室后常规监测心电图、无创血压及血氧饱和度。氧和 3%地氟醚吸入诱导插管 ,全凭吸入地氟醚麻醉。采用Dixon’sup and down方法 ,交叉出现 6对切皮不动 动的患者即终止。 6对切皮不动 动患者切皮时地氟醚浓度的平均值即为MAC。结果　 17例患者中出现 6对不动 动的交叉对 ,MAC为 (5 0 8± 0 2 6 ) %。结论　老年人地氟醚MAC较文献报道的年轻人MAC小。     

年龄对妇科手术七氟醚麻醉清醒肺泡浓度的影响

目的观察年龄对妇科手术七氟醚麻醉清醒肺泡浓度(MAC-awake)的影响。方法择期行妇科短小手术患者60例,ASAⅠ或Ⅱ级,依据年龄均分为三组:Ⅰ组,20~29岁;Ⅱ组,30~39岁;Ⅲ组,40~50岁。8%七氟醚诱导,眼睑反射消失后维持呼气末七氟醚浓度3%10 min后插入喉罩,术中七氟醚浓度维持在3%。手术结束后以0.1%浓度梯度按Dixon序贯法调整七氟醚浓度并拔出喉罩。计算意识恢复时呼气末七氟醚的MAC-awake即EC50及相应的95%可信区间(CI)。结果Ⅰ、Ⅱ、Ⅲ组意识恢复时呼气末七氟醚EC50及相应的95%CI分别为0.64%(0.57%~0.70%)、0.55%(0.50%~0.60%)及0.44%(0.37%~0.50%)。结论妇科手术七氟醚麻醉随着年龄增长其七氟醚的MAC-awake逐渐下降。     

可乐定降低异氟醚最低肺泡有效浓度的研究

研究了麻醉前应用可乐定影响异氟醚最低肺泡有效浓度（ＭＡＣ）的效应。设可乐定组和对照组各１５例，采用随机双盲法给药，根据Ｅｇｅｒ法确定ＭＡＣ值。发现麻醉前２小时口服可乐定５μｇ／ｋｇ，可使异氟醚１ＭＡＣ从对照组的１．１８５％降至０．７７５％，降低百分率为３４．６０％。推测此与可乐定的中枢性镇静、镇痛等效应有关。证实可乐定可做为麻醉前用药，降低异氟醚ＭＡＣ。研究中采用皮肤电刺激为切皮刺激确定ＭＡＣ预设     

The minimum alveolar concentration of sevoflurane in cats

Eight adult cats of either sex were studied. The minimal alveolar concentration (MAC) for sevoflurane in the cats was found to be 2.58 ± 0.30% (mean ± SD). The ratios of MAC values between sevoflurane and halothane, enflurane and isoflurane in cats were very similar to those ratios found in humans and dogs. This observation suggests that the results of this study are correct and allows us to estimate unknown MAC values for sevoflurane in other species using known MAC values for other anesthetic agents.(Doi M, Yunoki H, Ikeda K: The minimum alveolar concentration of sevoflurane in cats. J Anesth 2: 113–114, 1988)     

新生及成年大鼠七氟醚MAC值的测定

目的测定并比较新生及成年大鼠七氟醚的最低肺泡有效浓度(MAC)。方法选择健康新生及成年SD大鼠各25只。两组大鼠分别放入自制大鼠麻醉装置,露出其尾部。七氟醚气体经麻醉机挥发罐输入麻醉装置。采用序贯法及夹尾刺激测定七氟醚MAC。七氟醚初始测定浓度为1.5%,调节梯度为±0.2%。每间隔20 min重复夹尾试验判断麻醉效果并抽取气体样本3~5 ml测定七氟醚浓度。如此反复,使每只大鼠均获得一个阳性与阴性反应的交叉点。组内每只大鼠MAC值的均值即为该组大鼠的MAC值。结果新生大鼠MAC值为(2.58±0.11)%,明显高于成年大鼠的MAC值(2.32±0.13)%(P0.01)。结论新生大鼠的七氟醚MAC值明显高于成年大鼠,达到同一麻醉深度时新生大鼠所需七氟醚浓度更高。     

Anesthesia with 1.5 minimum alveolar concentration sevoflurane is not altered by physostigmine as measured by bispectral and clinical indices

STUDY OBJECTIVE: To evaluate the effect of physostigmine on 1.5% sevoflurane anesthesia and recovery. DESIGN: Prospective, randomized, double-blinded study. SETTING: Operating room of a university-affiliated, metropolitan hospital (Aretaieion Hospital and St Savas Hospital). PATIENTS: Forty female American Society of Anesthesiologists physical status I and II patients scheduled for breast biopsy. INTERVENTIONS: Patients were randomly assigned in physostigmine (PHYSO) and normal-saline (NS) group. Anesthesia was induced with sevoflurane 8% using a vital capacity breath technique, and rocuronium 0.6 mg/kg was given to facilitate Laryngeal Mask Airway (LMA) No. 4 insertion. Anesthesia was maintained with end-tidal sevoflurane 1.5 minimum alveolar concentration (MAC; 3% end-tidal concentration) throughout the procedure. MEASUREMENTS: After skin closure and under steady-state sevoflurane anesthesia 1.5 MAC, heart rate, blood pressure, and Bispectral Index (BIS) were recorded. Immediately after, the PHYSO group received intravenous 2 mg of physostigmine, whereas the NS group received equal volume of normal saline. Bispectral Index and hemodynamic measurements were recorded 5, 8, and 10 minutes after treatment. Anesthesia was then discontinued and the LMA was removed. Zero, 15, and 30 minutes after LMA removal, patients were evaluated for orientation, sedation, sitting ability, and the "picking up matches" test, as well as for nausea and vomiting. MAIN RESULTS: No difference was found in BIS (29 +/- 4, 32 +/- 6, 31 +/- 6, 30 +/- 7, 84 +/- 11 in the PHYSO group vs 29 +/- 6, 30 +/- 6, 30 +/- 5, 31 +/- 5, 86 +/- 7 in the NS group), hemodynamic parameters, or recovery parameters between the 2 groups at any time. No nausea or vomiting was observed in either group. CONCLUSIONS: Physostigmine did not influence BIS values or early recovery when administered to patients anesthetized with 1.5 MAC sevoflurane anesthesia.     

Minimum alveolar concentration of sevoflurane for tracheal extubation in children

Background: One advantage of tracheal extubation during deep anaesthesia is that respiratory complications are reduced. Sevoflurane is a suitable anaesthetic agent for children. This study was conducted to determine the minimum alveolar concentration of sevoflurane required to prevent cough or movement during and after tracheal extubation (MAC_extubation).
Methods: We studied 30 nonpremedicated children, aged 2–10 yr, undergoing plastic surgery. They were allocated randomly to five groups (end-tidal sevoflurane concentrations: 2.0, 2.5, 3.0, 3.5, 4.0%). After surgery, 60% nitrous oxide was discontinued and the target concentration of sevoflurane was maintained for at least 10 min in 100% oxygen, then the trachea was extubated to determine MAC_extubation. Logistic regression was used to estimate MAC_extubation. of sevoflurane.
Results: MAC_extubation. was 2.3 (0.2; standard error)% (95% confidence limits: 1.2% and 2.7%).
Conclusions: Tracheal extubation in 50% of anaesthetized children age 2–10 yr may be accomplished without coughing or moving at 2.3% end-tidal concentration of sevoflurane.     

Effects of propofol on the minimum alveolar concentration of sevoflurane for immobility at skin incision in adult patients

Study ObjectiveTo determine the effect of propofol on skin incision at target plasma concentrations of one to 6 μg/mL on the minimum alveolar concentration (MAC) of sevoflurane.DesignProspective, randomized, single-blinded study.SettingOperating room of a university hospital.Patients122 adult, ASA physical status I and II patients with cholecystitis and gastric cancer, presenting for elective abdominal surgery.InterventionsEach group received propofol at different target-controlled plasma concentrations of 0, 1, 2, 3, 4, 5 and 6 μg/mL, respectively. The end-tidal concentration of sevoflurane was stable at a predetermined value for at least 15 minutes. Skin incision was performed after return of neuromuscular function.MeasurementsPatients were observed for gross purposeful movement for one minute after skin incision. Heart rate and mean arterial pressure were recorded before induction of anesthesia, before incision, and after incision.Main ResultsThe MAC of sevoflurane when used alone was 2.2% ± 0.11%. Propofol decreased the MAC of sevoflurane by 12.3% at one μg/mL, 30.5% at two μg/mL, 35% at three μg/mL, 46.8% at 4 μg/mL, 57.7% at 5 μg/mL, and 72.7% at 6 μg/mL. The linear regression equation of the interaction between sevoflurane and propofol was Y = 2.1679 – 0.256 X, R² = 0.9407, where X = plasma propofol concentration, Y = sevoflurane concentration, and R² = correlation coefficient.ConclusionsPropofol decreases the MAC of sevoflurane in a concentration-dependent manner in adult patients.     

不同剂量右美托咪啶对七氟醚抑制切皮诱发患者体动反应肺泡气最低有效浓度的影响

目的 探讨不同剂量右美托咪啶对七氟醚抑制切皮诱发患者体动反应肺泡气最低有效浓度(MAC)的影响.方法 择期拟在全麻下行下腹部手术患者,性别不限,年龄18～64岁,体重指数21 ～ 27 kg/m2,ASA分级Ⅰ或Ⅱ级.采用随机数字表法,将其随机分为4组:对照组(C组)和不同剂量右美托咪啶组(D1组、D2组和D3组).麻醉诱导前静脉输注右美托咪啶(生理盐水稀释至15 ml)0.2μg/kg(D1组)、0.4 μg/kg(D2组)、0.6μg/kg(D3组)或生理盐水15 ml(C组),30 min内输注完毕.4组均采用吸入七氟醚麻醉诱导,气管插管后行机械通气.采用序贯法确定麻醉维持期间呼气末七氟醚浓度.C组、D1组、D2组及D3组第1例患者呼气末七氟醚浓度分别设定为3.0％、3.0％、2.5％和2.0％,预定呼气末七氟醚浓度稳定15 min时进行切皮.评估患者切皮时体动反应,当发生体动反应时,上调一个浓度梯度,否则下调一个浓度梯度,相邻浓度比值为0.9,根据前一例患者是否发生体动反应确定下一例患者呼气末七氟醚浓度,直至每组出现第7个交叉点.以各交叉点呼气末七氟醚浓度的均数作为MAC值,并计算95％可信区间 (CI).结果 C组、D1组、D2组和D3组入选病例分别18、20、20、22例；C组、D1组、D2组和D3组七氟醚MAC值(95％CI)分别为2.5％(2.3％～2.8％)、1.5％(1.3％～1.7％)、1.3％(1.0％～1.6％)和1.1％(0.7％ ～ 1.5％).与C组比较,D1组～D3组七氟醚MAC值降低(P＜0.05)；与D1组比较,D2组和D3组七氟醚MAC值降低(P＜0.05)；D2组和D3组七氟醚MAC值差异无统计学意义(P＞0.05).结论 右美托咪啶0.2、0.4、0.6 μg/kg可明显降低七氟醚抑制手术患者切皮诱发体动反应的MAC值,且呈剂量依赖性.