Continuous sciatic nerve infusion: Expanded case report describing a new approach

Background and Objectives. Severe pain following extensive reconstructive foot surgery is difficult to manage effectively. Sciatic nerve block provides excellent analgesia for a limited duration. I wanted to determine an approach to sciatic nerve block enabling an infusion of a local anesthetic for a prolonged period without loss of efficacy due to catheter displacement. Methods. Seventy-six consecutive sciatic nerve catheter placements—in 73 patients undergoing reconstructive foot surgery—were performed by four different approaches. Soft epidural catheters were found to be unsatisfactory—both for placement and for prolonged infusion. A firmer catheter, also capable of “through the catheter” nerve stimulation, was developed and proved to be satisfactory on both counts. Traditional approaches proved satisfactory for identifying the nerve but were unsatisfactory for prolonged infusion. A unique “in line” approach was developed to enable the insertion of the catheter along the course of the sciatic nerve, thus maintaining position for prolonged infusions. Results. According to predetermined criteria for success, only 64% of placements using traditional epidural catheters were successful, whereas the firmer catheter with “through the catheter” nerve stimulation was successful in 95% of placements. Conclusions. The described “in line” technique of continuous sciatic nerve infusion of a local anesthetic solution gives prolonged and effective analgesia following foot surgery.     

Thigh abscess as a complication of continuous popliteal sciatic nerve block

We present a case report of severe localized infection aftercontinuous popliteal sciatic nerve block. The report highlightsthe importance of meticulous asepsis and possibly limiting theduration of catheter use.     

Bifocal schwannoma of the sciatic nerve: a case report

Schwannoma is a benign tumor generally observed on peripheral nerves. A sciatic localization is rare, observed in 1% of the patients. Multiple localizations have been reported in exceptional cases. We report the case of a bifocal schwannoma observed at the bifurcation of the sciatic nerve in a high-level athlete. The misleading clinical presentation of this localization causes a delay in diagnosis.     

Propofol: bolus or continuous infusion

Forty patients undergoing vaginal termination of pregnancy were randomly allocated to receive a propofol anaesthetic using either a repeat bolus or infusion technique. The Ohmeda 9000 Infusion Pump was used in the study. Patients in the infusion group recorded significantly longer induction times, greater maintenance doses and prolonged immediate recovery characteristics. Both techniques offered cardiovascular stability but no advantages were demonstrated for the infusion technique over a conventional repeat bolus method.     

程控硬膜外间歇脉冲注入与持续背景输注用于分娩镇痛的比较

目的比较程控硬膜外间歇脉冲注入(programmed intermittent epidural bolus,PIEB)和持续背景输注(CEI)两种模式联合PCEA用于分娩镇痛的临床效果。方法自愿接受分娩镇痛足月、单胎和头位初产妇200例,随机分为两组,每组100例。在宫口扩张2~3 cm时采用硬膜外阻滞行分娩镇痛。PIEB组背景输注剂量为8 ml/h,给药速度为6 ml/min,每小时给药一次;CEI组以8ml/h的速度持续给药。观察产妇镇痛前(T0)、镇痛后10 min(T1)、30 min(T2)、1 h(T3)、2 h(T4)、宫口开全时(T5)、分娩时(T6)、分娩后1 h(T7)BP、VAS评分、改良Bromage评分;PCEA追加次数、罗哌卡因、舒芬太尼的用量、宫缩情况、胎心率、产程时间、镇痛时间、分娩方式、产妇使用催产素、不良反应、新生儿Apgar评分、产妇满意度评分。结果 T4~T6时PIEB组VAS评分明显低于CEI组(P0.01)。PIEB组PCEA追加次数、药物用量明显少于CEI组(P0.05),PIEB组产妇满意度明显高于CEI组(P0.05)。两组产妇的血压、宫缩持续时间和间隔时间、胎心率、产程、镇痛时间、分娩方式、使用催产素比例、不良反应发生率及新生儿Apgar评分差异无统计学意义。结论与采用CEI+PCEA模式比较,PIEB+PCEA模式的PCEA追加率更低、用药量更少、VAS评分更低、产妇的满意度更高,而不良反应并没有增加。     

A randomized comparison of programmed intermittent epidural bolus with continuous epidural infusion for labor analgesia

Bolus injection through an epidural catheter may result in better distribution of anesthetic solution in the epidural space compared with continuous infusion of the same anesthetic solution. In this randomized, double-blind study we compared total bupivacaine consumption, need for supplemental epidural analgesia, quality of analgesia, and patient satisfaction in women who received programmed intermittent epidural boluses (PIEB) compared with continuous epidural infusion (CEI) for maintenance of labor analgesia. The primary outcome variable was bupivacaine consumption per hour of analgesia. Combined spinal epidural analgesia was initiated in multiparas scheduled for induction of labor with cervical dilation between 2 and 5 cm. Subjects were randomized to PIEB (6-mL bolus every 30 min beginning 45 min after the intrathecal injection) or CEI (12-mL/h infusion beginning 15 min the after the intrathecal injection). The epidural analgesia solution was bupivacaine 0.625 mg/mL and fentanyl 2 microg/mL. Breakthrough pain in both groups was treated initially with patient-controlled epidural analgesia (PCEA) followed by manual bolus rescue analgesia using bupivacaine 0.125%. The median total bupivacaine dose per hour of analgesia was less in the PIEB (n = 63) (10.5 mg/h; 95% confidence interval, 9.5-11.8 mg/h) compared with the CEI group (n = 63) (12.3 mg/h; 95% confidence interval, 10.5-14.0 mg/h) (P < 0.01), fewer manual rescue boluses were required (rate difference 22%, 95% confidence interval of difference 5% to 38%), and satisfaction scores were higher. Labor pain, PCEA requests, and delivered PCEA doses did not differ. PIEB combined with PCEA provided similar analgesia, but with a smaller bupivacaine dose and better patient satisfaction compared with CEI with PCEA for maintenance of epidural labor analgesia.     

Unintentional side error for continuous sciatic nerve block at the popliteal fossa

Among all fields of healthcare about 45% of medical errors occur in the operating theatre. Wrong site procedures remain one of the most preventable medical errors. Unintentional wrong-sided peripheral nerve block is relatively a rare event in anesthesia care. However, the incidence is unknown but each time wrong-sided block occurs it represents a mistake and a potential for harm. The surgical safety checklist was established in 2008 by the world Health organization (WHO) as a part of the "Safe surgery save Lives" initiative. We report in this article a case of wrong sided continuous popliteal sciatic nerve block and discuss the role of the WHO's checklist in preventing wrong side peripheral nerve block and surgery.     

持续泵注与间断静脉给予罗库溴铵的药效学比较

目的比较罗库溴铵持续泵注与间断给药的药效学特点,探讨其最佳的给药方式.方法50例ASAⅠ～Ⅱ级,无神经肌肉疾患,全麻下行择期手术的病人,随机分成罗库溴铵间断给药组(Ⅰ组)和持续泵注组(Ⅱ组),采用TOF刺激方式,监测拇内收肌的收缩反应.记录神经肌肉阻滞的最大阻滞时间及起效时间、恢复过程,并记录罗库溴铵的用药量.应用静脉麻醉药诱导及维持.全部病例均未予拮抗,使其在安静状态下自然恢复.当TOF恢复至T4/T1≥70%时,结束肌松监测,呼吸恢复满意后拔管.结果Ⅰ组维持肌松追加用药的间隔时间平均(29.24±6.26)min,各次追加的间隔时间之间无明显差异;Ⅱ组的平均泵注速率为(6.31±1.93)μg@kg-1@min-1,与Ⅰ组单位时间平均用量(5.43±1.46)μg·kg-1·     

Ultrasound-guided sciatic nerve block

Theoretically, sciatic nerve block can be used alone or in combination with lumbar plexus block or femoral nerve block for anesthesia and/or analgesia of lower limb surgery. However, clinical use of sciatic nerve block was limited by technical difficulties in performing the block since techniques used relies only on surface anatomical landmarks. Recent advances in ultrasound technology allow direct visualization of nerves and other surrounding structures and have increased the interest in performing many kinds of peripheral nerve blocks including sciatic nerve block. Preliminary data suggest that ultrasound-guided technique can help perform the sciatic nerve block more reliably and safely. In this article we describe the anatomy of the sciatic nerve, sonographic features, and technique of three major approaches including subgluteal, anterior, and popliteal approaches. The use of this technique for postoperative analgesia is also discussed.     

Continuous sciatic nerve block

A technique of continuous sciatic nerve block is described. The method was used to relieve pain from ischaemic gangrene of the foot for 2 days before below-knee amputation and, combined with a continuous inguinal paravascular block, to provide regional anaesthesia both for the surgery and for the first 2 postoperative days.