Effects of intravenous or endotracheal lidocaine on circulatory changes during Recovery from general anesthesia

Intravenous lidocaine (1.5mg·kg^–1) was not effective in attenuating the circulatory changes and the cough reflex induced by airway stimulation during recovery from general anesthesia, whereas endotracheal 4% lidocaine (3ml) was effective. The arterial concentration of the intravenously administered-lidocaine peaked at a level of 9.52 ± 0.81µg·ml^–1 0.5min later. The arterial concentration of the endotracheally administered-lidocaine peaked at 1.44 ± 0.13µg·ml^–1 15min later. These findings indicate that the endotracheal administration of lidocaine may be superior to the intravenous administration for attenuating the circulatory changes and the cough reflex during recovery from general anesthesia, and that the arterial concentration of lidocaine did not correlate with the clinical efficacy for this purpose.(Okuda M, Furuhashi K, Konishi K et al.: Effects of intravenous or endotracheal lidocaine on circulatory changes during recovery from general anesthesia. J Anesth 4: 331–336, 1990)     

Response to double-burst appears before response to train-of-four stimulation during recovery from non-depolarizing neuromuscular blockade

Background: Double-burst stimulation (DBS) it a relatively new nerve stimulation mode introduced for improved manual detection of residual neuromuscular blockade. Previous studies have shown that DBS_{3,3 50/50} (3 stimuli at 50 Hz followed 0.75 seconds later by 3 stimuli at 50 Hz) can detect deeper degrees of neuromuscular blockade than train-of-four (TOF) stimulation.
Aim: The aim of the present study was to examine if DBS_{3,3 80/40} (3 stimuli at 80 Hz followed 0.750 s later by 3 stimuli at 40 Hz) can detect even deeper degrees of neuromuscular blockade than DBS_{3,3 50/50} and to determine the time lapse from reappearance of response to each of the two DBS modes until reappearance of response to the TOF mode of nerve stimulation.
Methods: The study comprised 20 women undergoing gynaecological surgery and anaesthetised with fentanyl, thiopentone, halothane, and nitrous oxide. Neuromuscular transmission was monitored by using mechanomyography and stimulation of the ulnar nerve. Atracurium was used for neuromuscular blockade.
Results: Elapsed time from reappearance of response to DBS_{3,3 80/40} and DBS_{3,3 50/50} to reappearance of response to TOF stimulation was 459±196 (mean±SD) and 360±150 seconds, respectively, ( P <0.05).
Conclusions: DBS_{3,3 80/40} is capable of detecting deeper degrees of blockade than DBS_{3,3 50/50} which again is capable of detecting deeper degrees of blockade than TOF.     

硬膜外注入不同浓度利多卡因对全麻病人异丙酚及异氟醚用量的影响

目的 观察在相同麻醉深度下,硬膜外注入不同浓度利多卡因对全麻病人异丙酚及异氟醚用量的影响。方法 45例择期上腹部手术病人,根据复合硬膜外用药的不同随机分为三组:生理盐水对照组(Ⅰ组)、1％利多卡因组(Ⅱ组)、2％利多卡因组(Ⅲ组),每组15例。硬膜外阻滞平面确定后麻醉诱导以25 mg/min异丙酚连续输注至病人神志消失;麻醉维持吸入异氟醚使脑电双频谱指数(BIS)值维持在50-55,硬膜外以7 ml/h泵注维持。记录异丙酚用量、异氟醚呼气末浓度(ETiso)及BIS、听觉诱发电位指数(AAI)。结果 病人意识消失时异丙酚用量:Ⅰ组(1.7±0.4)mg/kg、Ⅱ组(1.2±O.3)mg/kg和Ⅲ组(1.0±0.3)mg/kg,Ⅲ组和Ⅱ组异丙酚用量比Ⅰ组明显减少(P<0.01)。ETiso分别为Ⅰ组(0.85±0.10)％,Ⅱ组(0.65±0.06)％,Ⅲ组(0.57±0.12)％,Ⅱ组、Ⅲ组比Ⅰ组和Ⅲ组比Ⅱ组明显降低(P<0.01或0.05)。结论 维持相同的麻醉深度下,硬膜外注入1％利多卡因组比2％利多卡因组既能减少全麻药的用量,又能保持循环的相对稳定。     

利多卡因超声雾化吸入给药药代动力学研究

目的研究利多卡因经超声雾化吸入给药的药代动力学。方法12例择期全麻病人,随机分为两组,分别吸入利多卡因100mg(Ⅰ组)、200mg(Ⅱ组),不同时间点静脉取血,采用高效液相色谱技术测定利多卡因的血药浓度,用药代动力学计算程序(3p87)处理。结果利多卡因雾化吸入后血药浓度随着雾化吸入剂量的增加而增加,两组峰值浓度(Cmax)分别为(311.5±51.3)和(639.8±9.9)ng/ml;达峰浓度时间(Tpeak)分别为(0.22±0.04)和(0.31±0.06)h,半衰期(T1/2Ke)分别为(0.73±0.07)和(0.74±0.08)h。结论利多卡因雾化吸入的药代动力学符合一级吸收的一房室模型。     

右美托咪定与利多卡因抑制芬太尼诱发全麻诱导期患者呛咳反应效果的比较

目的 比较右美托咪定与利多卡因抑制芬太尼诱发全麻诱导期患者呛咳反应的效果.方法 择期妇科手术患者200例,ASA分级Ⅰ或Ⅱ级,年龄36 ～ 50岁,均采用全凭静脉麻醉,采用随机数字表法,将其分为2组(n=100):右美托咪定组(D组)和利多卡因组(L组).D组于麻醉诱导前20min静脉输注右美托咪定0.5 μg/kg,输注速率0.05 μg·kg-1· min-1,L组于麻醉诱导前1 min缓慢静脉注射利多卡因0.5 mg/kg.麻醉诱导最先使用芬太尼,2 min后给予其他诱导药物,记录注射芬太尼后1 min内呛咳反应的发生情况及程度.记录观察期内不良事件的发生情况.结果 与D组比较,L组呛咳反应发生率升高,呛咳程度严重(P＜0.05).两组低血压和严重窦性心动过缓的发生率比较差异无统计学意义(P＞0.05).结论 麻醉诱导前静脉注射右美托咪定0.5 μg/kg抑制芬太尼诱发全麻诱导期患者呛咳反应的效果优于利多卡因0.5 mg/kg.     

不同剂量罗库溴铵对腔镜甲状腺切除术中喉返神经监测的影响

目的：探讨不同剂量罗库溴铵对腔镜甲状腺切除术中喉返神经监测的影响。
方法：选择2021年10月至2022年10月行经乳晕入路腔镜甲状腺切除术的患者116例,男30例,女86例,年龄18～64岁,BMI 18.5～30.0 kg/m²,ASAⅠ或Ⅱ级。采用随机数字表法将患者分为三组：罗库溴铵0.30 mg/kg组（R1组,n=39）、罗库溴铵0.45 mg/kg（R2组,n=39）和罗库溴铵0.60 mg/kg（R3组,n=38）。麻醉诱导后,R1组、R2组和R3组分别静脉注射罗库溴铵0.30、0.45、0.60 mg/kg。当TOF值为0后插入神经监测气管导管,术中全程监测肌松,神经监测结束前不追加肌松药。记录首次出现喉返神经肌电图（EMG）时间及EMG振幅、插管时间及气管插管质量（Cooper''s评分法）。记录术中低血压、高血压、心动过缓、心动过速、体动的发生情况。记录术后咽痛、声音嘶哑、肌肉疼痛的发生情况。
结果：三组首次出现喉返神经EMG时间差异无统计学意义。与R1组比较,R2组和R3组首次出现喉返神经EMG振幅明显降低（P<0.05）。与R1组比较,R2组和R3组插管时间明显缩短（P<0.05）。与R2组比较,R3组插管时间明显缩短（P<0.05）。与R1组比较,R2组和R3组气管插管质量明显升高（P<0.05）。与R1组比较,R2组和R3组术中体动、术后咽痛发生率明显降低（P<0.05）。
结论：在腔镜甲状腺切除术中,与罗库溴铵0.30 mg/kg比较,罗库溴铵0.45和0.60 mg/kg既能提供良好的气管插管条件,又能监测到喉返神经肌电信号,罗库溴铵0.60 mg/kg插管时间更短。     

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。     

瑞芬太尼对全麻患者罗库溴铵肌松作用的影响

目的评价瑞芬太尼对全麻患者罗库溴铵肌松作用起效、维持和恢复时间的影响。方法45例择期手术患者,年龄20～65岁,ASAⅠ或Ⅱ级。随机分为3组(n=15):单纯异丙酚组(P组)、异丙酚复合瑞芬太尼组(R组)和单纯异氟醚组(Ⅰ组),观察并记录静脉注射插管剂量(2×ED95)的罗库溴铵后各组患者肌松起效、维持和恢复时间以及自主呼吸恢复的情况。结果三组肌松起效时间比较差异无统计学意义(P>0．05);Ⅰ组肌松维持时间、75％恢复时间和恢复指数均长于P组和R组(P<0．05),R组与P组比较差异无统计学意义(P>0．05)。R组患者术中无一例恢复自主呼吸,与Ⅰ组和P组比较差异有统计学意义(P<0．01)。结论术中靶控输注瑞芬太尼对罗库溴铵的肌松作用无影响。     

利多卡因预防罗库溴铵静脉注射痛的研究进展

背景 利多卡因作为酰胺类局部麻醉药,常用于预防罗库溴铵引发的静脉注射痛,可能机制为阻断外周神经细胞膜电压门控Na+通道,抑制Na+内流,产生膜稳定作用,并阻断痛觉传导通路,最终缓解注射痛.目的 本文拟对利多卡因预防罗库溴铵静脉注射痛的研究进展进行综述,为该药在临床工作中的应用提供参考. 内容 本文分别从作用机制以及同其他药物比较两个方面,综述利多卡因预防罗库溴铵注射痛的效果.趋向 利多卡因作为经典局部麻醉药之一,其在临床麻醉中具有越来越广泛的用途.     

新辅助化疗对乳腺癌患者罗库溴铵肌松效应的影响

目的 探讨新辅助化疗对乳腺癌患者罗库溴铵肌松效应的影响。
方法 选择2018年7月至2019年2月择期全凭静脉麻醉下行乳腺癌根治术的患者60例,年龄29～60岁,BMI 18～29 kg/m²,ASA Ⅰ或Ⅱ级,根据术前是否接受新辅助化疗分为化疗组（C组）和非化疗组（NC组）,每组30例。C组术前接受阿霉素联合紫杉醇（AT）或阿霉素、环磷酰胺联合紫杉醇（AC-T）方案化疗4周期后行手术治疗;NC组术前未接受新辅助化疗,直接行手术治疗。记录两组患者术前电解质、肝肾功能和入室时、插管即刻、肌松监测值（T₁%）恢复至10%、25%、75%时的HR、MAP、SpO₂ ;采用闭环肌松靶控注射系统进行罗库溴铵给药及肌松监测,T1%做为肌松监测值,监测罗库溴铵起效时间（注罗库溴铵毕到T1%降至0的时间）,10%恢复时间（注罗库溴铵毕到T1%恢复至10%的时间）,恢复指数（T1%恢复到25%至75%的时间）,并记录两组患者术中麻醉药物用量。
结果 两组患者术前电解质、肝肾功能和术中不同时点HR、MAP、SpO₂ 差异无统计学意义。与NC组比较,C组罗库溴铵起效时间明显延长（P＜0.05）,10%恢复时间明显缩短（P＜0.05）,罗库溴铵用量明显增多,平均输注速率明显增快（P＜0.05）。两组恢复指数、丙泊酚、瑞芬太尼、右美托咪定用量差异无统计学意义。
结论 新辅助化疗后行乳腺癌根治手术的患者术中罗库溴铵起效时间明显延长,10%恢复时间明显缩短,且罗库溴铵用量明显增多。     

麻醉诱导期间异丙酚与利多卡因的相互作用

目的探讨麻醉诱导期间不同利多卡因浓度对睫毛反射、意识消失时异丙酚血药浓度和心血管系统的影响。方法选择38例择期手术病人应用微机控制靶控输注利多卡因维持不同目标浓度(Ct)，其后从另一接口输注异丙酚，逐渐增加异丙酚目标浓度直至意识消失。根据利多卡因目标浓度将病人分为5组，分别为A组Oug·ml     

硬膜外麻醉时可乐定和肾上腺素对麻醉效果和血清利多卡因浓度的影响

目的　研究硬膜外麻醉时 ,利多卡因溶液中加用可乐定或肾上腺素对血清利多卡因浓度和硬膜外麻醉效果的影响。方法　将 3 0例 ASA ～ 级下腹或下肢择期手术患者随机分为三组 :1组为利多卡因空白对照组 ,单纯 2 %利多卡因 6mg· kg- 1 硬膜外注射 ;2组为肾上腺素对照组 ,2 %利多卡因 6m g· kg- 1 加肾上腺素 5μg· ml- 1 硬膜外注射 ;3组为可乐定试验组 ,2 %利多卡因 6mg·kg- 1 加可乐定 5μg· m l- 1 硬膜外注射。测定感觉和运动阻滞的起效和恢复时间 ,并采集动脉血检测血清利多卡因浓度。结果　利多卡因溶液中加用可乐定 ( 1∶ 2 0万 ) ,可使硬膜外麻醉起效加快、作用间期延长 ,并能降低血清利多卡因浓度 ,其作用类似于利多卡因溶液加用同等浓度的肾上腺素。结论　可乐定作为一种血管活性因子可应用于硬膜外麻醉 ,以减少利多卡因的毒副作用     

术中磁共振成像对持续泵注罗库溴铵肌松效应的影响

目的 观察神经外科手术术中磁共振成像(iMRI)对罗库溴铵肌松效应的影响.方法 采用前瞻、随机、对照研究.择期行开颅手术的患者30例,ASA Ⅰ或Ⅱ级,随机均分为两组:iMRI组(M组)和非iMRI组(C组).采用加速度仪四个成串刺激(TOF)监测肌松.两组采用相同的保温措施.麻醉诱导后给予罗库溴铵0.6 mg/kg,T1为0时静脉泵注罗库溴铵0.3～0.7Mg·kg-1·h-1,维持T1在0～5%.关闭硬脑膜时停止泵注罗库溴铵.记录T1恢复25%、TOF恢复25%、75%、90%的时间,停止泵注罗库溴铵至手术结束时间,罗库溴铵用量等.结果 术中M组患者腋温逐渐升高,而C组逐渐降低.手术时M组和C组腋温分别为(37.00±0.36)℃和(35.53±0.74)℃.M组TOF 25%、TOF 75%、TOF 90%时间显著短于C组(P<0.05或P<0.01).结论 iMRI可使患者体温升高,加快罗库溴铵TOF 25%的恢复,缩短临床及体内作用时间,但对于恢复指数无显著影响.     

静脉输注利多卡因对腹腔镜全子宫切除术患者镇痛效果的影响

目的观察静脉输注利多卡因对腹腔镜全子宫切除术患者术后镇痛效果的影响。方法选择我院择期全麻下行腹腔镜全子宫切除术患者80例,年龄28~65岁,体重42~76kg,ASAⅠ或Ⅱ级,采用随机数字表法将患者随机分为利多卡因组(L组)和对照组(C组),每组40例。L组于麻醉诱导前静脉注射利多卡因1.5mg/kg,随后以2mg·kg~(-1)·h~(-1)的速度持续输注至手术结束,C组以同样方法静脉输注等容量生理盐水100ml。术毕两组患者均使用舒芬太尼自控静脉镇痛,维持VAS评分≤3分。分别于术后2、4、8、12、24和48h行Ramsay镇静评分和BCS舒适度评分,记录患者术后24h舒芬太尼用量、额外追加舒芬太尼用量、自控镇痛次数、术后首次排气、排便时间、恶心、呕吐发生情况以及住院时间。结果与C组比较,L组患者术后2、4、8、12和24h的Ramsay镇静评分和BCS舒适度评分明显升高(P0.05),术后24h舒芬太尼用量[(34.8±5.8)μg vs(49.8±12.5)μg]、额外追加舒芬太尼用量[(22.5±2.6)μg vs(46.2±3.8)μg]、自控镇痛次数[(20±4)次vs(48±6)次]明显减少(P0.05),术后首次排气[(17±6)h vs(27±7)h]、排便时间[(26±8)h vs(47±9)h]以及住院时间[(4.5±0.5)d vs(5.6±0.8)d]明显缩短(P0.05),术后恶心[2例(5%)vs 8例(20%)]明显减少(P0.05)。结论静脉输注利多卡因可提高腹腔镜下全子宫切除术患者术后镇痛效果,节俭术后阿片类镇痛药物的用量,促进患者术后肠道功能的恢复,缩短患者住院时间。     

Kinemyography (KMG) versus Electromyography (EMG) neuromuscular monitoring in pediatric patients receiving cisatracurium during general anesthesia

Aim of the workTo compare KMG versus EMG neuromuscular monitoring in pediatric patients receiving cisatracurium during general anesthesia.MethodsAfter approval of the protocol by Ethics Committee 24 pediatric patients of both sexes aged 2–6 years, with a maximum weight 20 kg, were included in the study. Monitoring equipments (Datex-Ohmeda A/S 5?) were attached to the patient. The electromyogram was attached to one hand, while, KMG was attached to the other hand for simultaneous monitoring. Induction of anesthesia with fentanyl 2 μg/kg and propofol 2 mg/kg followed by endotracheal intubation. Anesthesia was maintained by end-tidal isoflurane 1.2%. Ventilation was kept by 50% oxygen in air and was adjusted to maintain end-tidal CO₂ in the range of 35–40 mm Hg. After a stable baseline period of at least 3 min, the 24 patients were received 0.1 mg/kg cisatracurium twice the 95% effective dose (2 × ED₉₅). The following parameters were collected and compared; (1) lag time (time from start of muscle relaxant administration until the first measurable neuromuscular block (NMB), (2) onset time (time from start of muscle relaxant administration until maximal NMB), (3) assessing the recovery period by; train of four (TOF) 0.25, 0.50, 0.75 and 0.90 (time to reach a TOF ratio of 25%, 50%, 75% and 90%, respectively). No top-up doses of muscle relaxants were given.ResultsThere was no statistical difference between both studied groups as regard the demographic data of the patients, the lag time, the onset time, TOF 0.25, 0.5, 0.75 and 0.9 ratios using either EMG or KMG. In addition, there is excellent degree of agreement between EMG and KMG in measuring TOF ratio during both induction and recovery of muscle relaxants.ConclusionsKMG showed an excellent degree of agreement with EMG for determination of onset and recovery of NMB in children.     

不同肌松程度对腹腔镜胃切除术患者术后早期恢复的影响

目的 评估深度肌松和中度肌松对腹腔镜胃切除术患者术后早期恢复的影响。方法选择2021年1月至2022年1月行腹腔镜胃切除术的患者79例，男53例，女26例，年龄45～64岁，BMI 18～28 kg/m²,ASAⅡ或Ⅲ级。患者随机分为两组：深度肌松组(D组)和中度肌松组(M组),每组40例。D组术中静脉泵注罗库溴铵0.5～0.6 mg·kg^-1·h^-1,维持强直刺激后单次刺激肌颤搐计数(PTC)在1～2次之间。M组术中静脉泵注罗库溴铵0.2～0.3 mg·kg^-1·h^-1,维持四个成串刺激(TOF)保持出现1～2个肌颤搐。记录术中丙泊酚、瑞芬太尼用量，拔管时间、PACU停留时间、首次排气时间、首次排便时间、术后住院时间。于入室即刻、术后24、48 h抽取外周静脉血，检测二胺氧化酶(DAO)和D-乳酸。记录术后恶心呕吐(PONV)、苏醒期躁动、苏醒延迟、术后寒战发生情况。使用手术状态评分评价术者对肌松效果的满意度。结果 两组术中丙泊酚、瑞芬太尼用量差异无统计学意义。与M组比较，D...     

静脉输注利多卡因在术后镇痛中的应用

背景 术后疼痛依然是麻醉医师所面临的挑战之一.作为术后镇痛的一线药物,阿片类药物常伴有一些副作用也会影响患者术后的恢复.任何可以减少阿片类药物的用量,并增强术后镇痛效果的多模式术后镇痛方案均推荐用于术后镇痛.研究发现静脉输注利多卡因可以增强术后镇痛效果,降低术后阿片类药物的用量,促进术后胃肠功能的恢复. 目的 现就静脉输注利多卡因对术后镇痛的影响作一综述. 内容 从镇痛机制、药代动力学特点、给药策略以及对不同手术术后镇痛效果的影响等方面分别进行探讨. 趋向 静脉输注利多卡因可以增强腹部术后镇痛效果,减少阿片类药物的用量,但其对其他手术术后镇痛效果的影响及最佳镇痛方案函待进一步研究.     

经硬膜外穿刺针注入利多卡因对剖宫产术连续硬膜外麻醉效应的影响

目的评价经硬膜外穿刺针注射局麻药后再置管对剖宫产术连续硬膜外麻醉效应的影响。方法单胎足月妊娠拟在连续硬膜外麻醉下行子宫下段剖宫产术的产妇100例,ASAⅠ或Ⅱ级,随机均分为研究组（P组）和对照组（C组）。硬膜外穿刺成功后,P组先通过硬膜外针注入2%利多卡因,注射完后保持注射器压缩针栓20 s,使液体充分扩散后再置入硬膜外导管;C组置入硬膜外导管后再注入2%利多卡因。记录置入硬膜外导管时的不良反应;测量给药完毕后20 min的麻醉平面,并评估麻醉满意度;记录置管时主诉异感和发生单侧阻滞的例数。结果与C组比较,P组硬膜外穿刺针针尾见淡红色血水的发生率（14%vs.36%）、硬膜外导管回抽出淡红色血水的发生率（4%vs.16%）明显降低（P<0.05）。P组利多卡因用量为（312±18）mg,明显少于C组的（355±32）mg（P<0.01）。给药后20 minP组的麻醉平面达T_5.6±0.8,明显高于C组的T_6.5±1.1（P<0.01）,且麻醉满意度显著增加（96%vs.84%）（P<0.01）。结论硬膜外置管前从硬膜外针注入局麻药不仅能有效减少置管对剖宫产产妇硬膜外血管的损伤,而且还能显著提高麻醉效果,减少局麻药的用量。     

Different recovery of the train-of-four ratio from rocuronium-induced neuromuscular blockade in the diaphragm and the tibialis anterior muscle in rat

PURPOSE: To clarify differences between the diaphragm and the limb muscles in terms of the effects of neuromuscular blockers concerning train-of-four (TOF) ratios, we compared the recovery of twitch tensions and TOF ratios in the diaphragm and in the tibialis anterior muscle in rats in vivo. METHODS: We conducted a dose-response study in 16 rats and a recovery study in 8 rats. In the recovery study, we made phrenic nerve-diaphragm and sciatic nerve-tibialis anterior preparations simultaneously in each of 8 rats that were anesthetized intraperitoneally with pentobarbitone (30 mg x kg(-1)) and urethane (500 mg x kg(-1)). After supramaximal stimuli were applied simultaneously in a TOF pattern to both the phrenic and sciatic nerves, rocuronium was injected intravenously, at 10 mg x kg(-1). In the diaphragm and the tibialis anterior muscle, we monitored the first-twitch response to TOF stimuli (T1) and also the TOF ratios. The following variables were determined for each muscle: (1) the times at which T1 recovered to 25%, 50%, and 75% of control T1, and the times at which the TOF ratio recovered to 25%, 50%, and 75%; and (2) the values of the TOF ratio at 25%, 50%, and 75% recovery of T1. RESULTS: At 25%, 50%, and 75% recovery of T1 in the diaphragm, TOF ratios were 8.9 +/- 5.0 %, 26.7 +/- 7.7 %, and 55.9 +/- 5.4%, respectively, while in the tibialis anterior, the TOF ratios were 18.0 +/- 5.9%, 32.5 +/- 7.4%, and 54.4 +/- 7.5%, respectively (diaphragm vs tibialis anterior; P < 0.01 for comparisons at both 25% and 50% recovery of T1). CONCLUSION: Our method of simultaneous in vivo evaluation of TOF ratios in both the diaphragm and the tibialis anterior confirmed significant differences between the two muscles in relationships between first-twitch tension and the TOF ratio.