左旋布比卡因与布比卡因在腰硬联合麻醉中的应用比较

[目的]比较左旋布比卡因与布比卡因用于腰硬联合麻醉下行妇科手术的临床效果.[方法]拟在腰硬联合麻醉下行妇科手术患者60例,ASA Ⅰ～Ⅱ级,年龄20～60岁,随机分成两组（n=30）.L组蛛网膜下腔注射0. 5%左旋布比卡因15 mg＋10%葡萄糖1 mL配成重比重液,B组蛛网膜下腔注射0.5%布比卡因15 mg＋10%葡萄糖1 mL配成重比重液,观察两组感觉阻滞起效时间、运动阻滞起效时间、最高感觉阻滞平面上界、感觉阻滞开始消退时间、运动阻滞程度及麻醉质量评分.[结果]两组患者的感觉阻滞起效时间、运动阻滞起效时间、最高感觉阻滞平面上界、感觉阻滞开始消退时间均无显著性差异（P〉0.05）.运动阻滞程度2～3分者,L组低于B组（P〈0.05）.L组感觉阻滞开始时间和运动阻滞程度短于B组（P〈0.05）,两组患者麻醉质量评分差异无显著性.B组在麻醉后30 min时收缩压（SBP）较L组有明显降低（P〈0.05）,而心率（HR）和舒张压（DBP）无明显改变.[结论]0.5%左旋布比卡因用于腰硬联合阻滞麻醉时具有满意的麻醉效果且手术后运动阻滞恢复更快,对患者血流动力学影响更小,是临床上布比卡因的良好替代品.     

The pre-emptive analgesic effect of intra-articular bupivacaine in arthroscopic knee surgery

BACKGROUND: The purpose of this study was to determine whether intra-articular injection of bupivacaine prior to surgery provided better pain control after arthroscopic meniscectomy as compared with post-operative administration of bupivacaine. METHODS: Forty patients of American Society of Anesthesiologists (ASA) class I or II undergoing arthroscopic meniscectomy were assigned in a randomized, double-blinded manner into two groups: Group I received 20 ml of 2.5 mg/ml bupivacaine without epinephrine 30 min before skin incision and 20 ml of saline immediately after skin closure. Group II received identical injections in reverse order. All patients received total intravenous anesthesia. Post-operative pain scores were evaluated at 1, 2, 4, 6, 8, 12 and 24 h at rest and movement of the knee, using a 10-cm visual analog scale (VAS). The time to first analgesic use and 24-h analgesic consumption were recorded. RESULTS: Pain scores were lower in Group I compared with Group II at 1, 2, 4 and 6 h at rest and on movement (P < 0.05). The time to first analgesic use was longer in Group I, but there was no statistically significant difference in 24-h analgesic consumption. CONCLUSION: Intra-articular bupivacaine administered before surgery provided a statistically significant reduction in post-operative pain scores compared with post-operative bupivacaine administration.     

蛛网膜下腔注药速度对剖宫产脊麻感觉阻滞平面的影响

 目的 通过比较脊麻剖宫产手术蛛网膜下腔不同注药速度的布比卡因半数有效剂量(median effective dose,ED50)探讨注药速度对脊麻感觉阻滞平面的影响。方法 选择ASAⅠ～Ⅱ级拟在腰硬联合麻醉下行择期剖宫产的足月单胎妊娠产妇70例,电脑随机数字法分为快速注药组(F组,n=35)和慢速注药组(S组,n=35),F组与S组蛛网膜下腔分别以0.25和0.025 mL/s的速度注射0.5％等比重布比卡因。采用序贯法进行试验,每组第一例产妇的布比卡因剂量均为6.5 mg,剂量变化梯度为0.5 mg,感觉阻滞有效定义为局麻药注射完毕后15 min双侧无痛的阻滞平面达T6或以上。若上一例产妇有效,则下一例布比卡因的剂量降低0.5 mg,若上一例产妇无效,则下一例产妇布比卡因的剂量增加0.5 mg,采用Dixon Mood法计算两种注药速度时布比卡因ED50及其95％的可信区间(95％CI)。结果 F组布比卡因的ED50及其95％CI为6.17(6.03～6.32)mg,S组布比卡因的ED50及其95％CI为7.23(7.00～7.46)mg,F组布比卡因的ED50低于S组(P＜0.001)。结论 局麻药的推注速度是影响脊麻感觉阻滞平面的因素之一,在一定范围内,注药速度越快,剖宫产手术脊麻时达到相同阻滞平面所需的药物剂量越小。     

Intrathecal midazolam added to bupivacaine improves the duration and quality of spinal anaesthesia

BACKGROUND: The antinociceptive action of intrathecal midazolam is well documented. In this prospective study, we investigated the addition of midazolam to intrathecal bupivacaine on the duration and quality of spinal blockade. METHODS: Forty ASA I or II adult patients undergoing lower abdominal surgery were selected for the study. The patients were randomly allocated to receive 3 ml of 0.5% hyperbaric bupivacaine intrathecally either alone or with 1 mg of midazolam using a combined spinal epidural technique. The duration and quality of sensory and motor block, perioperative analgesia, haemodynamic changes, and sedation levels were assessed. RESULTS: The duration of sensory block (i.e. time to regression to the S2 segment) was significantly longer in the midazolam group than the control group (218 min vs. 165 min; P < 0.001). The duration of motor block was also prolonged in the midazolam group as compared with the control group (P < 0.01). In 90% of the patients in the midazolam group, the quality of block was adequate during the intra-operative period as compared with only 65% of the patients in the control group (P < 0.05). The duration of effective analgesia was longer in the midazolam group than in the control group (199 vs. 103 min; P < 0.001). Blood pressure, heart rate, oxygen saturation and sedation scores were comparable in both groups. No neurological deficit or other significant adverse effects were recorded. CONCLUSION: The addition of intrathecal midazolam to bupivacaine significantly improves the duration and quality of spinal anaesthesia and provides prolonged perioperative analgesia without significant side-effects.     

Randomized double-blind comparison of ropivacaine-fentanyl and bupivacaine-fentanyl for spinal anaesthesia for urological surgery

BACKGROUND: Early studies have suggested that ropivacaine causes less motor block than bupivacaine, which might be advantageous in spinal anaesthesia for short procedures. The aim of this study was to compare plain ropivacaine 10 mg and plain bupivacaine 10 mg, both with fentanyl 15 microg, for spinal anaesthesia in urological surgery. Methods: This was a prospective randomized double-blind study. After written informed consent had been obtained, 34 ASA I-III patients scheduled for urological surgery were randomly assigned to receive intrathecal injection of either plain ropivacaine 10 mg with fentanyl 15 microg (ropivacaine group) or plain bupivacaine 10 mg with fentanyl 15 microg (bupivacaine group) using a combined spinal-epidural technique. RESULTS: All patients achieved sensory block to the T10 dermatome or higher at 15 min after intrathecal injection. One patient in the ropivacaine group was excluded because of unexpectedly prolonged surgery. The primary outcome, the duration of motor block, was shorter in the ropivacaine group (median, 126 min; interquartile range, 93-162 min) compared with the bupivacaine group (median, 189 min; interquartile range, 157-234 min; difference between medians, 71 min; 95% confidence interval, 28-109 min; P = 0.003). The duration of complete motor block was also shorter in the ropivacaine group compared with the bupivacaine group. There was no difference in the onset time of motor block. The characteristics of sensory block and the haemodynamic changes were similar between the groups. CONCLUSION: Plain ropivacaine 10 mg plus fentanyl 15 microg provided similar sensory anaesthesia, but with a shorter duration of motor block, compared with plain bupivacaine 10 mg plus fentanyl 15 microg when used for spinal anaesthesia in urological surgery.     

Clonidine addition prolongs the duration of caudal analgesia

BACKGROUND: In this study, using a dose-ranging design, we examined the effects of clonidine with 0.125% bupivacaine on the duration of post-operative analgesia in caudal anaesthesia in children. METHODS: We conducted a controlled, prospective study of clonidine in caudal anaesthesia in 60 children, aged 1-10 years, undergoing elective inguinal hernia repair. Induction and maintenance of anaesthesia were performed by inhalation of sevoflurane and nitrous oxide. The children were randomized in a double-blind fashion to four groups, and were given a caudal anaesthetic with either 0.125% plain isobaric bupivacaine (1 ml/kg) or bupivacaine plus 1, 1.5 or 2 microg/kg of clonidine. The blood pressure and heart rate were recorded peri-operatively. Analgesia was evaluated by the modified Children's Hospital of Eastern Ontario Pain Scale (mCHEOPS) or a visual analogue scale (VAS). Paracetamol was given when the mCHEOPS score was greater than five or when the VAS score was greater than 30 mm. The monitoring of scores for pain, haemodynamic changes and post-operative nausea and vomiting was performed by nurses blind to the study allocation. RESULTS: The duration of analgesia was found to be significantly longer in the group given bupivacaine plus 2 microg/kg of clonidine (median, 650 min; range, 300-900 min). Peri-operative hypotension and bradycardia, post-operative respiratory depression and motor block were not recorded in any patient. CONCLUSIONS: The addition of clonidine to 0.125% bupivacaine prolongs the duration of post-operative analgesia without any respiratory or haemodynamic side-effects.     

Injectable and topical local anesthetics for acute dental pain: 2 systematic reviews

BackgroundLocal anesthesia is essential for pain control in dentistry. The authors assessed the comparative effect of local anesthetics on acute dental pain after tooth extraction and in patients with symptomatic irreversible pulpitis.Types of Studies ReviewedThe authors searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and the US Clinical Trials registry through November 21, 2020. The authors included randomized controlled trials (RCTs) comparing long- vs short-acting injectable anesthetics to reduce pain after tooth extraction (systematic review 1) and evaluated the effect of topical anesthetics in patients with symptomatic pulpitis (systematic review 2). Pairs of reviewers screened articles, abstracted data, and assessed risk of bias using a modified version of the Cochrane risk of bias 2.0 tool. The authors assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation approach.ResultsFourteen RCTs comparing long- vs short-acting local anesthetics suggest that bupivacaine may decrease the use of rescue analgesia and may not result in additional adverse effects (low certainty evidence). Bupivacaine probably reduces the amount of analgesic consumption compared with lidocaine with epinephrine (mean difference, –1.91 doses; 95% CI, –3.35 to –0.46; moderate certainty) and mepivacaine (mean difference, –1.58 doses; 95% CI, –2.21 to –0.95; moderate certainty). Five RCTs suggest that both benzocaine 10% and 20% may increase the number of people experiencing pain reduction compared with placebo when managing acute irreversible pulpitis (low certainty).Practical ImplicationsBupivacaine may be superior to lidocaine with epinephrine and mepivacaine with regard to time to and amount of analgesic consumption. Benzocaine may be superior to placebo in reducing pain for 20 through 30 minutes after application.     

Bupivacaine inhibits the TLR4- and TLR2-Myd88/NF-κB pathways in human leukocytes

Local anesthetics have anti-inflammatory effects. Because most previous experiments were performed with supra-therapeutic concentrations, we measured the effects of clinically relevant concentrations of bupivacaine on the Toll like receptor 4 (TLR4)- and TLR2-myeloid differentiation primary response 88 (MyD88)-nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) pathways. We measured tumor necrosis factor alpha (TNF-α) and prostaglandin E2 (PGE2) release, p38 mitogen-activated protein kinase (MAP-kinase) phosphorylation and translocation of NF-κB in human peripheral blood mononuclear cells (hPBMCs) and human monocytes challenged with lipopolysaccharide (LPS) or tripalmitoylated lipopeptide Pam3CysSerLys4 (Pam3CSK4) in the presence or absence of bupivacaine. Similarly, we measured the effect of bupivacaine on HEK293 cells expressing the hTLR4 and the hTLR2 genes and challenged with LPS or Pam3CSK4. Finally, molecular docking simulations of R(+)- and S(−)-bupivacaine binding to the TLR4-myeloid differentiation protein 2 (MD-2) complex and to the TLR2/TLR1 heterodimer were performed. In PBMCs, bupivacaine from 0.1 to 100 μM inhibited LPS-induced TNF-α and PGE2 secretion, phosphorylation of p38 and nuclear translocation of NF-κB in monocytes. Bupivacaine similarly inhibited the effects of Pam3CSK4 on TNF-α secretion. Bupivacaine inhibited the effect of LPS on HEK293 cells expressing the human TLR4 receptor and the effect of Pam3CSK4 on HEK293 cells expressing the human TLR2 receptor. Molecular docking showed that bupivacaine binds to the MD-2 co-receptor of TLR4 and to the TLR2 receptor. Contrary to numerous experiments performed with supratherapeutic doses, our results were obtained with concentrations of bupivacaine as low as 0.1 μM. We conclude that bupivacaine modulates the inflammatory reactions such as those observed after surgery or trauma, at least partly by inhibiting the TLR4- and TLR2-NF-κB pathways.     

Comparison of Femoral Nerve Catheter,Adductor Canal Catheter,and Periarticular Liposomal Bupivacaine Infiltration for Postoperative Analgesia After Primary Total Knee Arthroplasty

BackgroundPeripheral nerve catheters are used to provide analgesia after total knee arthroplasty (TKA) and have been shown to decrease pain and opioid use, to facilitate participation with physical therapy (PT), and to hasten discharge. More recently, pericapsular infiltration using liposomal bupivacaine (LB) has been employed as an alternative analgesic approach.MethodsThis retrospective study compared outcomes for three analgesic approaches: femoral nerve catheter (FNC), adductor canal catheter (ACC), and intraoperative LB infiltration. The primary outcome was numeric rating scale (NRS) pain scores at 24 hours. Secondary outcomes included pain scores at 12, 36, and 48 hours, time-to-first opioid, cumulative opioid use, distance walked, and time-to-discharge.ResultsPain scores at 24 hours were significantly lower in both the ACC and FNC cohorts when compared to the LB cohort (3.1 versus 4.6 [P = .017] and 2.4 versus 4.6 [P < .0001]). The ACC and FNC groups did not differ significantly at that timepoint (P = .27). Similar comparisons were found at 12 and 36 hours, while at 48 hours the FNC group was superior. Time to first opioid and opioid consumption favored the ACC and FNC groups. Walking distance favored the ACC group. Both the ACC and LB groups had a faster time-to-discharge than the FNC group.ConclusionBoth ACCs and FNCs provided superior analgesia at 24 hours compared to LB, while being equivalent to each other. Pain scores at 12 hours and 36 hours as well as opioid consumption through 48 hours mirrored this finding. Although various differences were found between groups in terms of time-to-first analgesic, walking distance and time-to-discharge, the ACC approach appeared to optimally balance analgesia, ambulation, and time-to-discharge.