七氟烷对体外循环冠状动脉旁路移植术患者左心室功能的影响

目的 评价七氟烷对体外循环(CPB)冠状动脉旁路移植术(CABG)患者左心室功能的影响.方法 择期CPB下行CABG的冠心病患者35例,男性30例,女性5例,年龄53～75岁,身高150～183 cm,体重46～100 kg,AsAⅡ或Ⅲ级,七氟烷分为冠脉搭桥前后2个阶段给药,分别为气管插管后至锯胸骨前和关闭胸腔至手术结束前,CPB期间停止吸入七氟烷.七氟烷呼气末浓度相当于1 MAC.围术期行食管超声心动图(TEE)检查,于锯胸骨前未吸入七氟烷(T_1)、吸入5 min(T_2)、15 min(T_3)、关闭胸腔后未吸入七氟烷(T_4)、吸入5 min(T_5)、15 min(T_6)时记录平均动脉压(MAP)和TEE监测指标:E波、A波、S波.D波和AR波的峰值、心指数(CI)、左室短轴缩短率(FS)、左室射血分数(LVEF),左心室舒张早期血流播散速度(Vp),计算E波与A波峰值比(E/A)、S波与D波峰值比(S/D) 和E波与Vp的比值(E/Vp).结果 与T_1时比较,T_(2,3)时MAP降低,T_3时LVEF、FS和CI降低,T_4时HR、LVEF、FS、CI升高,.E波:A波、S波、D波和AR波的峰值升高(P<0.05或0.01);与T_4时比较,T_(5,6)时MAP降低,T_6时LVEF、FS和CI降低(P<0.05或0.01).结论 呼气末浓度相当于1 MAc的七氟烷可明显抑制CPB下CABG患者左心室收缩功能,但对舒张功能无明显影响.     

七氟醚或丙泊酚麻醉诱导在纤维支气管镜引导下困难气管插管的临床研究

目的探讨全凭七氟醚吸入或丙泊酚静脉麻醉诱导在纤维支气管镜(纤支镜)引导下困难气管插管的安全性和可行性研究。方法 60例困难气道患者随机均分为全凭七氟醚吸入麻醉诱导组(S组)和丙泊酚静脉麻醉诱导组(P组)行纤支镜辅助下经鼻气管插管。观察插管前后患者的生命体征和麻醉深度变化。记录吸入诱导前(T0)、意识消失时(T1)、气管插管前(T2)、插管后1min(T3)、插管后5min(T4)时的HR、MAP、熵指数[(状态熵(SE)和反应熵(RE)]。结果两组纤支镜插管成功率基本相似。S组诱导迅速,但血流动力学变化明显。T3时S组HR明显快于、MAP明显高于T2时(P<0.05),同时S组HR明显快于,MAP明显高于P组(P<0.05)。两组SE和RE在T1～T4时均明显低于T0时(P<0.05)。P组体动和呛咳反应明显高于S组(P<0.05)。结论采用全凭七氟醚吸入麻醉诱导或丙泊酚静脉麻醉诱导均可安全用于纤支镜引导下困难气管插管的患者。     

静-吸复合麻醉和全凭静脉麻醉对肝炎肝硬化患者围术期免疫功能的影响

目的观察静-吸复合麻醉和全凭静脉麻醉对肝炎肝硬化患者围术期免疫功能的影响。方法择期行肝癌切除术的肝炎肝硬化患者60例,肝功能分级(Child-Pugh)为A或B级,ASAⅠ或Ⅱ级,随机均分为静-吸复合麻醉组(A组)和全凭静脉麻醉组(B组),每组30例。A组:麻醉诱导依次静脉注射芬太尼2~4μg/kg、咪达唑仑0.05mg/kg、依托咪酯0.2mg/kg、顺式阿曲库铵0.1~0.2mg/kg;麻醉维持:吸入2%~3%七氟醚、持续泵入瑞芬太尼0.1~0.2μg·kg-1·min-1、顺式阿曲库铵0.1~0.2mg·kg-1·h-1。B组:麻醉诱导时静注丙泊酚2mg/kg替代依托咪酯,麻醉维持时泵入丙泊酚4~6mg·kg-1·h-1替代吸入七氟醚,其他麻醉药同A组。分别在麻醉前30min(T0)、术毕即刻(T1)及术后72h(T2)采用流式细胞仪检测外周血T淋巴细胞亚群(CD3+、CD4+、CD8+、CD4+/CD8+)及NK细胞数量。结果与T0时比较,T1时两组CD3+、CD4+、CD4+/CD8+均明显下降(P0.05),且B组明显低于A组(P0.05);T2时A组各项指标均恢复至T0时,B组仍明显低于T0时(P0.05)。结论与全凭静脉麻醉比较,七氟醚静-吸复合麻醉对肝炎肝硬化患者围术期免疫功能的影响显著降低,术后免疫功能恢复较快。     

七氟醚对室间隔缺损患儿脑血管CO2反应性的影响

目的使用经颅多普勒超声监测脑血流,比较静脉麻醉药与七氟醚对室间隔缺损患儿脑血管二氧化碳反应性(cerebrovascular carbon dioxide reactivity,CO_2R)的影响。方法纳入3～12月龄患儿32例,随机分为两组。静脉组静注哌库溴铵0.2 mg/kg、咪达唑仑0.2 mg/kg及舒芬太尼1μg/kg,肌松满意后行气管插管,全凭静脉维持麻醉。吸入组持续吸入七氟醚1.5 MAC,静注哌库溴铵0.2 mg/kg,自主呼吸消失后行气管插管,七氟醚1.0 MAC维持麻醉。调整机械通气条件,使P_(ET)CO_2依次维持在30 mmHg(T_1)、35 mmHg(T_2)、40 mmHg(T_3)、45 mmHg(T_4),使用经颅多普勒超声测量右侧大脑中动脉血流平均速度(V_(MCA)),同时记录HR、心脏指数(CI)及BIS,计算CO_2R。结果T_1—T_4时两组V_(MCA)明显增加,HR明显减慢(P0.01);吸入组BIS值和CO_2R明显下降(P0.01或P0.05)。与静脉组比较,吸入组T_3和T_4时V_(MCA),T_1—T_4时HR、T_1—T_2时段CO_2R明显增高(P0.01或P0.05)。结论 1.0 MAC七氟醚麻醉下,在低P_(ET)CO_2范围内CO_2R更高,且高于使用静脉麻醉药物。     

不同浓度七氟醚麻醉对老年患者左心室功能的影响

目的评价超声心动图下不同浓度七氟醚麻醉对老年患者左心室功能的影响。方法选择全麻下择期手术患者120例,男59例,女61例,年龄65~69岁,ASAⅠ或Ⅱ级,采用随机数字表法按最低肺泡有效浓度(MAC)将患者随机分为四组,每组30例。分别维持呼气末MAC值为1.0(S1组)、1.5(S2组)、2.0(S3组)、2.5(S4组),维持上述预定值10min后静脉注射芬太尼、琥珀胆碱快速诱导气管插管,机械通气,调整吸入浓度。于麻醉诱导前即刻(T0)、呼气末七氟醚浓度达到并维持在预定值3min(T1)、5min(T2)、8min(T3)、10min(T4)时采用心动超声记录左心室舒张末期内径(LVEDD)、左心室收缩末期内径(LVESD)、左心室射血分数(LVEF)、左心室内径缩短率(LVFS)、心输出量(CO)。同时记录SBP、DBP、HR及吸入七氟醚期间心血管不良事件的发生情况。结果与T0时比较,T1~T4时四组SBP和DBP明显降低,T2~T4时S2、S3、S4组LVEF、LVFS和CO明显降低,S3、S4组LVESD明显升高(P0.05)。T2~T4时S2、S3、S4组LVEF、LVFS和CO明显低于S1组,S3、S4组LVESD明显高于S1组(P0.05)。T2时S3、S4组LVESD明显高于S2组(P0.05)。S1、S2组无一例低血压发生,S3、S4组分别发生6例(20%)和9例(30%)低血压,S3、S4组低血压发生率明显高于S1、S2组(P0.05)。结论低浓度七氟醚麻醉对老年患者左心室功能无明显影响,而高浓度七氟醚麻醉对左心室收缩功能有明显抑制作用,但对舒张功能无明显影响。     

七氟烷吸入麻醉对开胸手术病人术后血清cTnI及心肌酶水平的影响作用探讨

目的分析七氟烷吸入麻醉对开胸手术病人术后血清cTnI及心肌酶水平的影响。方法开胸手术的病人62例,将病人随机分为观察组(30例)和对照组(32例),其中观察组手术中使用七氟烷全程吸入麻醉,对照组采用丙泊酚全凭静脉麻醉。记录并比较两组病人麻醉诱导前、体外循环(CPB)开始后10分钟(T_1)、主动脉开放即刻(T_2)、主动脉开放后30分钟(T3)、主动脉开放后1小时(T_4)、CPB停机后6小时(T_5)、CPB停机后24小时(T_6) 7个时间点心肌肌钙蛋白I(cTnI)水平及心肌酶水平。结果两组病人7个时间点的cTnI浓度均呈递增趋势,且观察组在T_4和T_5时间点的浓度高于对照组;观察组T3时间点肌酸激酶同工酶及乳酸脱氢酶水平均低于对照组,差异均有统计学意义(P 0. 05)。结论吸入麻醉病人cTnI浓度普遍低于静脉麻醉病人,吸入性麻醉对心肌损害相对更轻,值得临床推荐。     

七氟醚和丙泊酚对腹腔镜下行子宫肌瘤切除术患者胰岛功能的影响

目的探讨七氟醚和丙泊酚对腹腔镜下行子宫肌瘤切除术患者胰岛功能的影响。方法选择择期行腹腔镜下子宫肌瘤切除术患者40例,年龄40~55岁,ASAⅠ或Ⅱ级,随机数字表法分为七氟醚组(S组)和丙泊酚组(P组),每组20例。所有患者采用丙泊酚2 mg/kg、舒芬太尼0.5μg/kg、罗库溴铵0.9mg/kg常规麻醉诱导,麻醉维持:S组吸入麻醉维持七氟醚MAC 0.7~1.3,P组靶控输注丙泊酚维持其血浆靶浓度为2.0~5.0μg/ml。术中控制BIS值在40~55,分别检测诱导前(T_0)、手术开始时(T_1)、手术结束时(T_2)的血糖、胰岛素、C肽、胰高血糖素、皮质醇浓度。结果与T0时比较,T_1、T_2时两组患者血糖、胰岛素、C肽、胰高血糖素、皮质醇明显升高(P0.05);与T_1时比较,T_2时两组患者血糖、胰岛素、C肽、胰高血糖素、皮质醇明显升高(P0.05)。T_1、T_2时P组血糖、胰高血糖素、皮质醇明显低于S组(P0.05),胰岛素明显高于S组(P0.05)。结论与七氟醚比较,丙泊酚更能促进胰岛素和C肽的分泌,抑制皮质醇和胰高血糖素的分泌,抑制术中血糖的升高。     

七氟醚静吸复合麻醉与全凭静脉麻醉用于小儿手术的比较

目的 比较七氟醚静吸复合麻醉与丙泊酚、芬太尼全凭静脉麻醉用于小儿手术的临床效果.方法 60例4～14岁ASA Ⅰ级择期行外科手术的小儿,随机均分为丙泊酚、芬太尼全凭静脉麻醉组(丙泊酚组)和七氟醚静吸复合麻醉组(七氟醚组).丙泊酚组静脉麻醉诱导,静脉麻醉药物维持.七氟醚组七氟醚麻醉诱导,七氟醚麻醉维持.记录术中血流动力学变化,术后麻醉恢复情况.结果 两组诱导方法都能实现快速诱导,且丙泊酚组麻醉诱导起效更快,意识消失时间、插管时间较七氟醚组缩短(P＜0.01).而七氟醚组麻醉诱导对心率的影响更小,诱导更平稳.七氟醚组苏醒时间、拔管时间、定向力恢复时间和PACU滞留时间均短于丙泊酚组(P＜0.01).结论 七氟醚静吸复合麻醉后术中循环稳定,术后清醒迅速、平稳,可安全有效地应用于小儿手术.     

七氟醚全凭吸入麻醉在婴儿唇裂整复术中的应用

目的 探讨七氟醚全凭吸入麻醉在婴儿唇裂整复术中应用的可行性和安全性.方法 60例ASA Ⅰ级唇裂婴儿随机均分为七氟醚全凭吸入麻醉组(S组)和丙泊酚-芬太尼静脉麻醉组(P组).记录患儿入室后、气管插管时、手术切皮时、手术开始后30 min的HR、MAP;记录拔管时间、改良Aldrete评分达9分所需时间、单位时间维库溴铵用量、苏醒期躁动及术后恶心呕吐情况.结果 P组气管插管时HR明显快于入室后及S组(P＜0.01);S组拔管时间和改良Aldrete评分到9分的时间均明显短于P组(P＜0.01);S组苏醒期躁动例数多于P组(P＜0.05);两组患儿均无苏醒期呕吐;S组患儿的维库溴铵用量显著小于P组(P＜0.01).结论 七氟醚全凭吸入麻醉维持平稳,苏醒迅速完全,可安全用于婴儿唇裂整复手术,其不足是苏醒期躁动发生率高.     

喉罩通气全凭吸入七氟醚麻醉用于乳腺癌改良根治术的临床观察

目的 探讨喉罩通气全凭吸入七氟醚麻醉用于乳腺癌改良根治术的临床效果.方法 择期乳腺癌手术患者60例,随机均分为全凭吸入七氟醚组(A组)和传统静吸复合组(B组).两组术前均给予盐酸戊乙奎醚1 mg肌注,咪唑安定2 mg静注.A组给予单纯七氟醚吸入诱导,置入喉罩成功后连接麻醉机机械控制呼吸,麻醉维持采用单纯七氟醚吸入;B组给予芬太尼4μg/kg、丙泊酚1 mg/kg、顺苯磺酸阿曲库铵0.15 mg/kg静注麻醉诱导,置入喉罩成功后连接麻醉机机械控制呼吸,麻醉维持采用七氟醚持续吸入,间断注射顺苯磺酸阿曲库铵维持肌松.监测两组患者不同时点的BP、HR、SpO2等指标.记录两组患者麻醉诱导至成功置入喉罩的时间和手术结束至拔除喉罩的时间.结果 两组患者在麻醉诱导置入喉罩时的心血管反应差异无统计学意义,麻醉开始诱导至睫毛反射消失的时间差异无统计学意义,术中生命体征差异亦无统计学意义,但手术结束至拔除喉罩的时间A组明显短于B组(P＜0.05).结论 乳腺癌改良根治术采用喉罩通气全凭吸入七氟醚麻醉,麻醉诱导及苏醒迅速,能满足喉罩置入及外科手术操作的麻醉要求,并且操作方便、安全性高.     

Liver and renal functions following total intravenous anesthesia using midazolam and fentanyl—comparison with enflurane-nitrous oxide anesthesia

Thirty patients undergoing lower abdominal surgery were studied to compare liver and renal functions in total intravenous anesthesia (TIVA) using midazolam and fentanyl with those in enflurane-nitrous oxide anesthesia (GOE). Patients were randomly divided into two groups of 15. In the TIVA group, anesthesia was induced with 0.3 mg·kg⁻¹ midazolam and maintained with 0.68 mg·kg⁻¹·h⁻¹ midazolam for 15 min followed by 0.125 mg·kg⁻¹·h⁻¹ midazolam and fentanyl. In the GOE group, anesthesia was induced with 5 mg·kg⁻¹ thiamylal and maintained with enflurane-nitrous oxide in oxygen. Plasma levels of aspartate aminotransferase, alanine aminotransferase (ALT), lactate dehydrogenase, total bilirubin, alkaline phosphatase, γ-glutamyl transpeptidase (γ-GTP), blood urea nitrogen (BUN), and creatinine (Cr) were measured before and at 1, 7, and 30 days after surgery. There were transient increases beyond the normal range in ALT and γ-GTP in both groups. BUN and Cr were within the normal range. There were no differences between the two groups regarding these parameters and the numbers with abnormally high levels of each parameter. In conclusion, liver and renal functions following TIVA using midazolam and fentanyl were the same as those following enflurane-nitrous oxide anesthesia. This work was performed at Kagawa Prefectural Central Hospital, and a part was presented at the 40th meeting of the Japan Society of Anesthesiology held in Morioka, Japan, in 1993     

Epidural anesthesia and pulmonary function

The epidural administration of local anesthetics can provide anesthesia without the need for respiratory support or mechanical ventilation. Nevertheless, because of the additional effects of epidural anesthesia on motor function and sympathetic innervation, epidural anesthesia does affect lung function. These effects, i.e., a reduction in vital capacity (VC) and forced expiratory volume in 1 s (FEV_1.0), are negligible under lumbar and low thoracic epidural anesthesia. Going higher up the vertebral column, these effects can increase up to 20% or 30% of baseline. However, compared with postoperative lung function following abdominal or thoracic surgery without epidural anesthesia, these effects are so small that the beneficial effects still lead to an improvement in postoperative lung function. These results can be explained by an improvement in pain therapy and diaphragmatic function, and by early extubation. In chronic obstructive pulmonary disease (COPD) patients, the use of thoracic epidural anesthesia has raised concerns about respiratory insufficiency due to motor blockade, and the risk of bronchial constriction due to sympathetic blockade. However, even in patients with severe asthma, thoracic epidural anesthesia leads to a decrease of about 10% in VC and FEV_1.0 and no increase in bronchial reactivity. Overall, epidural administration of local anesthetics not only provides excellent anesthesia and analgesia but also improves postoperative outcome and reduces postoperative pulmonary complications compared with anesthesia and analgesia without epidural anesthesia.     

Comparison of renal function under deliberate hypotension during epidural plus light-enflurane anesthesia and during enflurane anesthesia

We compared the effects of deliberate hypotension induced with trimethaphan on renal function and renal tubular damage under combined epidural and light-enflurane anesthesia (epidural group) and enflurane anesthesia alone (enflurane group). The mean arterial blood pressure was maintained at 50–55 mm Hg for 2.5 h in both groups using continuous infusion of trimethaphan. The urine volume and free water clearance were significantly greater in the epidural group than in the enflurane group [1.8±1.8 (SD)vs 0.4±0.3 ml·kg⁻¹·h⁻¹ and 0.81±1.30vs −0.15±0.22 ml·min⁻¹, respectively] (P<0.05). The creatinine clearance and fractional sodium excretion rate did not differ significantly between the two groups. Urinary excretion of norepinephrine was significantly less in the epidural group than in the enflurane group (P<0.05); however, epinephrine excretion did not differ. Urinary excretion ofN-acetyl-β-d-glucosaminidase was significantly less in the epidural group than in the enflurane, group (4.2±2.5vs 12.2±4.6 U·g⁻¹ CR) (P<0.01). The plasma antidiuretic hormone concentration was significantly lower in the epidural group compared to the enflurene group (13±23vs 57±42 pg·ml⁻¹) (P<0.05). No significant difference in plasma atrial natriuretic peptide concentration was found between the groups. We conclude that renal function during trimethaphan-induced hypotension is better maintained under epidural plus light-enflurane anesthesia than under enflurane anesthesia alone.     

紧闭循环麻醉时七氟醚对病人肝肾功能的影响

目的 评价紧闭循环麻醉时七氟醚对病人肝肾功能的影响.方法 拟行普外科手术病人40例,ASA Ⅰ或Ⅱ级,年龄20～60岁,随机分为2组(n=20),麻醉诱导后S1.组和S2组分别吸人6%～8%国产或进口七氟醚,新鲜气流量2～4 L/min,2～3 min后调整新鲜气流量至0.18～0.30 L/min,随后维持七氟醚呼气末浓度2.6%～3.5%.于术前、术毕、术后1、2、3和5 d时测定血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)活性、总胆红素(TB)、肌酐(Cr)、尿素(BUN)、β2-微球蛋白(β2-MG)浓度和尿液β2-MG浓度.结果 与术前比较,术毕、术后1、2 d时两组尿液β2-MG浓度升高(P<0.05),术后1～5血清ALT、AST活性和TB、Cr、BUN和β2-MG浓度差异无统计学意义(P0.05);各指标组间比较差异无统计学意义(P0.05).结论 紧闭循环麻醉时七氟醚对病人肝肾功能无明显影响.     

肌肉减少症患者的围术期麻醉管理

肌肉减少症作为老年疾病中的一种,并未引起临床的广泛关注。肌肉减少症常伴发其他疾病发生,影响患者的康复以及术后转归。麻醉科医师应该重视肌肉减少症患者的围术期管理。本文对肌肉减少症的现状、麻醉对骨骼肌的影响以及围术期麻醉管理的要点进行综述,希望引起麻醉科医师的关注。     

Immunosuppressive effects of anesthesia and surgery in the newborn: I short-term effects

We examined short-term effects of anesthesia and surgery on the lymphocyte response of neonates and older children to a range of mitogens using a whole blood mitogen stimulation assay. Following induction of anesthesia, both neonates and older children demonstrated significantly decreased lymphocyte transformation to phytohaemagglutinin (PHA; P less than 0.005) and Con A (P less than 0.025) compared with preanesthetic values. Immediately, postsurgery, older children recovered fully their responsiveness to both PHA and Con A, while there was significant depression in their responsiveness to PWM (P less than 0.005) and SPA (P less than 0.05). In contrast, neonatal responsiveness to all mitogens was significantly reduced (P less than 0.005) immediately after surgery compared to preoperative values. At 24-hour postsurgery, neonatal responsiveness to PHA had returned to preoperative levels but Con A, PWM, and SPA responses continued to decline (P less than 0.005). These results suggest that the newborn is particularly susceptible to the immunosuppressive effects of anesthesia and surgery.     

全麻下单肺通气对肺功能的影响

目的　探讨单肺通气状况的最佳呼吸方式。方法　 60例 ASA ～ 级开胸病人单肺麻醉时 ,在分钟通气量设定的条件下 ,随着吸气时间相对延长 (通过降低呼吸频率和吸∶呼比值 )的不同通气条件变化 ,对单肺功能和血气分析的影响进行了临床研究。结果　单肺通气时 ,在呼吸频率 =12次 /分 ,吸∶呼比值 =1∶ 1时 ,通气侧肺顺应性、实际分钟通气量和脉搏血氧饱和度明显改善 ,血气结果最佳 ,与双肺通气相比较无显著性差异 ( P>0 .0 5 ) ;气道压力显著降低 ,与单肺通气其它通气条件相比较有显著性降低 ( P<0 .0 5 )。但过分降低呼吸频率 ( RR<10次 /分 )达到的效果会适得其反。结论　在单肺通气使用麻醉呼吸器时 ,相对降低呼吸频率 ( RR=12次 /分 )、相对延长吸气时间 ( I∶ E=1∶ 1.5 ) ,可达到提高肺顺应性和通气量 ,降低气道压力 ,提高血氧和降低二氧化碳分压的良好效果     

电针对依托咪酯复合麻醉患者肾上腺皮质功能的影响

目的 探讨电针对依托咪酯复合麻醉患者肾上腺皮质功能的影响.方法 择期腹部手术患者80例,性别不限,年龄30 ～ 64岁,ASA分级Ⅰ级或Ⅱ级,采用随机数字表法,将其分为4组(n=20):丙泊酚对照组(P组)、依托咪酯组(E组)、依托咪酯+电针组(EEA组)和依托咪酯+假电针组(ES组).E组、EEA组和ES组采用咪达唑仑-依托咪酯-舒芬太尼-阿曲库铵行麻醉诱导,采用依托咪酯-瑞芬太尼维持麻醉;P组采用咪达唑仑-丙泊酚-舒芬太尼-阿曲库铵行麻醉诱导,采用丙白酚-瑞芬太尼维持麻醉.EEA组于麻醉诱导前至术毕行电针刺激[疏密波(2/50 Hz),波宽300 μs,刺激电流由0开始,以0.1 mA的梯度逐渐增大,逐渐达到患者能耐受的最大水平].于麻醉诱导前(T0)、手术开始后2 h(T1)、术毕(T2)、术后2 h(T3)时抽取静脉血样,采用ELISA法测定血清皮质醇、促肾上腺皮质激素(ACTH)、肾上腺素、去甲肾上腺素的浓度.结果 与P组比较,E组、EEA组和ES组T1-T3时血清皮质醇浓度降低,T3时血清ACTH浓度升高,EEA组T1、T2时血清肾上腺素浓度、T1-T3时血清去甲肾上腺素浓度降低(P＜0.05);与E组比较,EEA组T1-T3时血清皮质醇浓度升高,T3时血清ACTH浓度降低,T1、T2时血清肾上腺素浓度、T1-T3时血清去甲肾上腺素浓度降低(P＜0.05),ES组上述指标差异无统计学意义(P＞0.05).结论 电针可减轻依托咪酯复合麻醉对患者肾上腺皮质功能的抑制作用.     

Effects of magnesium sulfate on neuromuscular function and spontaneous breathing during sevoflurane and spinal anesthesia

The purpose of the present study was to determine the effects of magnesium sulfate (MgSO⁴) on the neuromuscular function and spontaneous breathing of patients under sevoflurane and spinal anesthesia. Twenty-two patients with a history of arrhythmia undergoing elective knee surgery were randomly assigned to two groups: group M (n = 11), administered with MgSO⁴ 40 mg·kg⁻¹, and group S (n = 11), administered with saline. A combination of spinal anesthesia with 2% sevoflurane inhalation was applied to all patients under spontaneous breathing. Tidal volume (Vt), respiratory rate (RR) and end-tidal carbon dioxide (ET^{CO 2}) were measured before the MgSO⁴ or saline injection and measurements were repeated at 5, 15, 30, and 45 min after the injection. Neuromuscular function was continuously monitored with an acceleromyograph to record the acceleration of the adductor pollicis by stimulating the ulnar nerve at a frequency of 0.1 Hz. The Vt, RR, and ET^{CO 2} showed little change in either group, and there was no significant difference between, the groups. The single-twitch response showed significant differences between the two groups (P = 0.0006). The present study indicated that the MgSO⁴ had a minimal effect on spontaneous breathing in patients undergoing sevoflurane and spinal anaesthesia, but that it attenuated the safety margin of neuromuscular function.