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1.

Background

Total knee arthroplasty is a treatment option for debilitating arthritis. In the postoperative period, patients experience moderate to severe pain affecting the rehabilitation, hospital stay, and patient satisfaction. This study aims at utilizing current best evidence to determine whether adductor canal block (ACB) or periarticular injection (PAI) is a better modality for managing short-term postoperative pain and opioid consumption.

Methods

Embase, MEDLINE, HealthStar, Emcare, and PubMed were searched for randomized controlled trials from 1946 to August 2018, for literature addressing the comparison of ACB and PAI for pain management in the setting of total knee arthroplasty. A systematic review and meta-analysis were performed.

Results

Six studies were included in our meta-analysis. When examining the combined visual analog scale (VAS) pain values for each group, analysis demonstrated greater reduction in scores for the PAI group, and the difference was statistically significant (P = .001). When comparing the VAS scores of subgroups analyzed at specific periods in time, there was a trend toward lower VAS scores in subgroups analyzed at 24 hours and 48 hours postoperatively (at rest and at movement) in the PAI group. Overall opioid consumption was lower in the PAI group, with demonstrated statistical significance (P = .03). When comparing the postoperative subgroups, there was a trend toward decreased opioid use in the PAI group, with 13.25% less opioid use at 48 hours and 9.5% less opioid use at 24 hours.

Conclusion

PAI could significantly improve postoperative pain and opioid consumption when compared with ACB. Additional, high-quality studies are required to further address this topic.  相似文献   
2.
A low concentration of transition metal ions Co2+ and Ni2+ increases the inward current density in neurons from the land snail Helix aspersa. The currents were measured using a single electrode voltage-clamp/internal perfusion method under conditions in which the external Na+ was replaced by Tris+, the predominant external current carrying cation was Ca2+, and the internal perfusate contained 120 mM Cs+/0 K+; 30 mM tetraethylammonium (TEA) was added externally to block K+ current. In the presence of Co2+ (3 mM) or Ni2+ (0.5 mM) inward Ca2+ currents were stimulated normally by voltage-dependent activation of Ca2+ channels. There was a 5-10% decrease in the rate of rise of the inward current. The principal effect of Co2+ and Ni2+ in increasing the current density seems to be a decrease in the rate at which the inward currents decline during a depolarizing voltage pulse. The results may be due to a decrease in a voltage-dependent or Ca(2+)-dependent outward current and/or an inhibition of Ca2+ channel inactivation. Outward current under these conditions (zero internal K+) was significant and most likely due to Cs+ efflux through the voltage-activated or Ca(2+)-activated nonspecific cation channels. Co2+ is an extremely effective blocker of this outward current. These results are not an artifact of internal perfusion or the special ionic conditions. Intracellular recording of unperfused neurons in normal Helix Ringer's solution showed that the Ca(2+)-dependent action potential duration was increased significantly by low concentrations of Co2+. This result is consistant with the Co(2+)-dependent increase in inward (depolarizing) current seen in voltage-clamp experiments.  相似文献   
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为比较硬膜外隙阻滞(硬外)、蛛网膜下隙阻滞(腰麻)和单侧蛛网膜下隙阻滞(腰麻)在75岁以上高龄股骨颈骨折手术中的阻滞效果及对循环的影响.选ASAⅢ~Ⅳ级90例,随机等分为3组,Ⅰ组为硬外阻滞组(A组),用1.5%Lidocaine 4ml试验剂量并确认无脊麻后,根据情况追加1.5%Lidocaine 4~6ml;Ⅱ组为腰麻组,Ⅲ组为单侧腰麻组,两组注药速度均为0.1ml·s-1,注药过程均不作往返吸注.Ⅱ组用0.75%布比卡因1ml(7.5mg),注药后仰卧;Ⅲ组患侧在下侧卧,用0.75%布比卡因0.6ml(4.5mg)、10%葡萄糖液0.4ml,注药20min后平卧.结果显示:①患侧痛觉阻滞起效由快到慢为Ⅱ组、Ⅲ组和Ⅰ组.②三组阻滞前后的心率比较,均无显著性差异;Ⅲ组阻滞前后的平均动脉压也无显著性差异,但Ⅰ和Ⅱ组的阻滞前后的平均动脉压均有显著性差异.③患侧痛觉阻滞达标率(无痛平面达L1的百分率)为Ⅰ组93.3%,Ⅱ和Ⅲ组均为100%.④阻滞不全者Ⅰ组3例,而Ⅱ和Ⅲ组则无.⑤发生低血压者Ⅰ和Ⅱ组各3例,且同时都伴有ECG的ST段下移;Ⅲ组则无.表明①单侧腰麻组起效较快、阻滞完善和患侧痛觉阻滞达标率高.②单侧腰麻所用剂量小,阻滞范围小,对循环干扰轻和阻滞平面似乎更易控制.因此,小剂量布比卡因单侧腰麻可能更适合高龄老人下肢手术.  相似文献   
6.
局部浸润和神经阻滞麻醉在会阴切开中的应用分析   总被引:1,自引:0,他引:1  
目的 探讨会阴切开时不同麻醉方式对产妇的影响.方法 将100例产妇随机分为左侧阴部神经阻滞麻醉组(阻滞组)和局部组织浸润麻醉组(浸润组),每组50例,比较两组产妇镇痛效果、缝合时间、第四产程出血量及产后72h活动的情况.结果 浸润组在镇痛效果、缝合时间、出血量及产后的活动方面均优于阻滞组.结论 在会阴切开缝合术中应用小剂量利多卡因作阴部浸润麻醉有效减轻了产妇的切口疼痛,缩短缝合时间,减少第四产程出血量.  相似文献   
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A new technique for looking at the atrioventricular node andbundle is described and applied to the conducting system insix patients with scleroderma. The conducting system blockswere removed, sectioned, appropriately stained and photographed.Outlines of the atrioventricular node and bundle were generatedand digitized. From the digital information three-dimensionalimages were generated and the atrioventricular node and bundlewere rotated so that the shape could be studied from any view.In striking contrast to normal atrioventricular nodal reconstructions,those from the patients who had scleroderma showed a narrowand flattened proximal atrioventricular node. The nodal microscopy,on the other hand, did not differ significantly in architecture.It is postulated that the alterations by fibrous replacementof the proximal node could account for the relatively high frequencyof atrioventricular conduction Scleroderma, problems in patientswith scleroderma and could paradoxically account for the relativelyfrequent occurrence of supraventricular tachycardias that arealso found in this disease.  相似文献   
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目的:研制一个肺挡铅固定架,使得该挡铅具有三自由度调节的空间定位功能,以保证使用的肺挡铅在全身放射治疗时定位精准.方法:设计制造一个装置,由3个部分组成:(1)装有4根挡铅固定柱的旋转轴及其轴套和锁紧螺栓;(2)透明材质制作的连接板;(3)通过燕尾槽相互契合的X、Y轴向滑块及其底座,并配有X和Y轴向调节螺栓.结果:此肺挡铅对位器,可做到:(1)肺挡铅能被轻松固定在拟定位置上;(2)肺挡铅的毫米级转向调节和任意角位调节,并且能反复修正至所需精度,重复定位误差≤2 mm; (3)肺挡铅的安装、定位时间大大缩短,20 min以内即可完成;(4)每一具装置承载铅块的质量可达20 kg.结论:此肺挡铅对位器可轻松、快速地实现肺挡铅的高精度空间定位.  相似文献   
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【目的】探讨术中在椎旁肌肉中注射药物对控制腰椎手术后疼痛的治疗作用。【方法】153例腰椎后路手术患者,分为肌肉封闭组78例,注射利多卡因+罗哌卡因;对照组75例,不作封闭治疗。分别观察术后不同时间两组VAS疼痛评分、住院期间肢体感觉、肌力、腱反射、平卧翻身及下地行走时间等。【结果】术后1d、1周、2周VAS评分,椎旁肌封闭组为(5.75±0.76)、(4.22±0.80)、(3.37±0.79),对照组则为(7.82±0.69)、(6.32±0.79)、(5.53±0.79),各时间点相比差异有统计学意义(P<0.01)。椎旁肌封闭组对止痛药物的依赖性低,患者术后平卧翻身时间(1.85±0.31)d和下地行走时间(3.09±0.39)d均较对照组(2.09±0.36)d和(3.47±0.43)d缩短,差异有统计学意义(P<0.01)。观察期间封闭组没有发现明显的胃肠道反应、心血管系统异常反应、尿潴留等不良反应。【结论】术中椎旁肌封闭能有效控制腰椎手术后的早期疼痛反应疼痛,对术后功能恢复有利。  相似文献   
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