Efficacy of continuous femoral nerve block with stimulating catheters versus nonstimulating catheters for anterior cruciate ligament reconstruction

BACKGROUND AND OBJECTIVES: This prospective randomized controlled trial investigated the clinical efficacy of stimulating catheters for continuous femoral nerve block in patients who underwent anterior cruciate ligament reconstruction. METHODS: Seventy patients were randomized to either a stimulating catheter (SC, n = 35) or a nonstimulating catheter (NSC, n = 35) for femoral nerve block using 25 mL ropivacaine 7.5 mg/mL and clonidine 50 microg injected through the catheter. A single-injection sciatic block was also given to ensure surgical anesthesia. The time to loss of sensation to cold and pinprick of the femoral nerve was registered as the onset time. Data were registered intra- and postoperatively regarding pain scores, adverse effects, and need for supplemental anesthesia and analgesia other than a continuous postoperative infusion of ropivacaine 2 mg/mL through the continuous femoral nerve catheter set at 7 mL/h. RESULTS: Onset time was faster in the SC group (SC: 6.4 +/- 2.5, NSC: 8.3 +/- 2.9 min, P = .006). Visual analog scale pain scores were similar in both groups. The number of patient-controlled regional analgesia boluses (SC: 14.6 +/- 12.6, NSC: 23.2 +/- 13.6 mg ropivacaine 2 mg/mL, P = .008) as well as intravenous rescue ketorolac (SC: 34.3 +/- 35.7, NSC: 54 +/- 39.7 mg, P = .033) administered were higher in the NSC group. CONCLUSION: Although the use of a stimulating catheter was associated with faster onset time for the femoral nerve block and lower additional analgesics postoperatively, the clinical superiority (analgesia; lateral femoral cutaneous, and obturator nerve block) of stimulating catheters was not evident in this clinical setting.     

Intra-articular injection versus interscalene brachial plexus block for acute-phase postoperative pain management after arthroscopic shoulder surgery

BackgroundThe minimally invasive approach of arthroscopic shoulder surgery is beneficial; however, for optimal outcomes, perioperative pain management is essential. This cross-sectional study aimed to examine the analgesic effectiveness of intra-articular injection (IA) versus interscalene brachial plexus block (ISPB) among patients treated with arthroscopic shoulder surgeries.MethodsWe reviewed 100 consecutive patients who underwent shoulder arthroscopic surgery, of whom 50 each underwent IA (February 2019─January 2020; IA group) and ISPB (October 2018─July 2019; ISPB group). The primary outcome was the postoperative pain score measured using a Wong–Baker FACES Pain Rating Scale preoperatively and at 2, 6, 12, 24, and 48 h postoperatively. We performed multiple regression analysis to examine whether IA/ISPB selection is associated with acute-phase postoperative pain and adjusted for intra-articular injection, interscalene brachial plexus block, postoperative pain management, arthroscopic shoulder surgery, IA with 10 mg of morphine previously reported prognostic factors for postoperative pain (e.g., surgical procedures, operative time, older age, and preoperative pain). Furthermore, we examined induction time, total pentazocine dosage, and total postoperative nausea and vomiting (PONV) events.ResultsThere were no significant differences between the IA and ISPB groups in perioperative pain control during the acute-phase periods (p = 0.12, repeated analysis of variance). The difference in anesthesia method was not a prognostic factor for acute-phase postoperative pain (p = 0.11). The IA group (15.06 ± 4.00 min) had a significantly shorter mean anesthesia induction time than the ISPB group (29.23 ± 9.22 min) (p = 0.0001). There was no significant between-group difference in the total pentazocine dosage during the first 7 days (p = 0.3934) postoperatively. PONV was observed in eight (17.0%) and two (4.2%) patients in the IA and ISPB groups, respectively. There was no significant between-group difference in the PONV incidence (p = 0.1582).ConclusionsThere was no significant difference in acute-phase postoperative pain management between the IA and ISPB groups. The induction time was significantly shorter in IA.IRBApproval number: UOEHCRB20-078, IRB approval date: September 9th, 2020; study duration: October 2018 to January 2020.     

Pleural effusion and chest pain after continuous interscalene brachial plexus block

Objective: We describe a unique case of a patient who experienced atelectasis of the lower lobe of the left lung and pleural effusion manifested by chest pain after continuous interscalene brachial plexus block for postoperative analgesia.Case Report: A 45-year-old man with no respiratory disease was scheduled for left shoulder arthroscopy for rotator cuff repair under interscalene brachial plexus block and sedation. A continuous interscalene brachial plexus block provided postoperative analgesia. On the first postoperative day, the patient reported left-sided chest pain. The chest x-ray showed elevation of the left hemidiaphragm associated with a left lower lobe atelectasis and a minor pleural effusion. After catheter removal, clinical and radiologic signs resolved within few days without sequela.Conclusion: If chest pain presents after interscalene brachial plexus block, early postoperative chest x-ray is recommended to rule out pneumothorax, atelectasis, and/or pleural effusion secondary to ipsilateral phrenic block.     

Ultrasound-guided bilateral continuous sciatic nerve blocks with stimulating catheters for postoperative pain relief after bilateral lower limb amputations

The performance of continuous bilateral sciatic nerve blocks under ultrasonographic control using stimulating catheters is described in a 4-year-old child with VACTERL syndrome. Ultrasound showed an abnormal vascular and nerve supply to the lower limbs. The use of ultrasound guidance made successful continuous sciatic nerve blocks possible in a child in whom the traditional method of nerve localisation was unlikely to succeed for anatomical reasons.     

Lidocaine versus ropivacaine for continuous interscalene brachial plexus block after open shoulder surgery

BACKGROUND: This study compared the postoperative infusion of 1% lidocaine and 0.2% ropivacaine for continuous interscalene analgesia in patients undergoing open shoulder surgery. METHODS: Forty patients undergoing open shoulder surgery received an interscalene brachial plexus block with 30 ml of either 1.5% lidocaine (n = 20) or 0.5% ropivacaine (n = 20), followed by a continuous patient-controlled interscalene analgesia with 1% lidocaine or 0.2% ropivacaine, respectively. A blinded observer recorded the quality of analgesia and recovery of motor function during the first 24 h of infusion. RESULTS: Onset of the block occurred after 7.5 (5-40) min with lidocaine and 30 (10-60) min with ropivacaine (P = 0.0005). Postoperative pain intensity was higher with lidocaine than ropivacaine for the first 8 h of infusion. The ratio between boluses given and demanded from the pump was 0.5 (0.13-0.7) with lidocaine and 0.7 (0.4-1.0) with ropivacaine (P = 0.005). Rescue IV tramadol was required during the first 24 h of infusion by 16 patients of the lidocaine group (84%) and eight patients of the ropivacaine group (46%) (P = 0.05). At the 16 h and 24 h observation times a larger proportion of patients receiving ropivacaine had complete regression of motor block (70% and 95%) than patients receiving lidocaine (50% and 55%) (P = 0.05 and P = 0.013, respectively). CONCLUSIONS: Although 1% lidocaine can be effectively used for postoperative patient-controlled interscalene analgesia, 0.2% ropivacaine provides better pain relief and motor function.     

Using stimulating catheters for continuous sciatic nerve block shortens onset time of surgical block and minimizes postoperative consumption of pain medication after halux valgus repair as compared with conventional nonstimulating catheters

We prospectively tested the hypothesis that the use of a stimulating catheter improves the efficacy of continuous posterior popliteal sciatic nerve block in 100 randomized patients scheduled for elective orthopedic foot surgery. After eliciting a sciatic mediated muscular twitch at < or = 0.5 mA nerve stimulation output, the perineural catheter was advanced 2-4 cm beyond the tip of the introducer either blindly (Group C; n = 50) or stimulating via the catheter (Group S; n = 50). A bolus dose of 25 mL of 1.5% mepivacaine was followed by a postoperative patient-controlled infusion of 0.2% ropivacaine (basal infusion: 3 mL/h; incremental dose: 5 mL; lockout time: 30 min). Propacetamol 2 g IV was administered every 8 h, and opioid rescue analgesia was available if required. Catheter placement required 7 +/- 2 min in Group S and 5 +/- 2 min in Group C (P = 0.056). A significantly shorter onset time of both sensory and motor blocks was noted in Group S. No difference in quality of pain relief at rest and during motion was reported between the groups. Median (range) local anesthetic consumption during the first 48 h after surgery was 239 mL (175-519 mL) and 322 mL (184-508 mL) in Groups S and C, respectively (P = 0.002). Rescue opioid analgesia was required by 12 (25%) and 28 (58%) patients in Groups S and C, respectively (P = 0.002). We conclude that the use of a stimulating catheter results in shorter onset time of posterior popliteal sciatic nerve block, similar pain relief with reduced postoperative consumption of local anesthetic solution, and less rescue opioid consumption. IMPLICATIONS: This prospective, randomized, blind investigation demonstrated that the use of a stimulating catheter for continuous posterior popliteal sciatic nerve block resulted in shorter onset time of sensory and motor blocks and less local anesthetic consumption and need for rescue pain medication after elective orthopedic foot surgery compared with blind catheter advancement.     

Real-time three-dimensional ultrasound for continuous interscalene brachial plexus blockade

Two-dimensional ultrasound guidance is used commonly for regional anesthetic techniques. This report describes the novel use of three-dimensional, ultrasound-guided, continuous interscalene regional analgesia, which was used in a 36-year-old woman undergoing left total elbow arthroplasty. Possible advantages of this novel technology over current two-dimensional methods include a larger area of available scan information that enables multiple planes of view without having to reposition the ultrasound probe, and three-dimensional visualization of local anesthetic deposition perineurally. Current technological limitations include an upper frequency of 7 MHz, which decreases the resolution of superficial scanning.     

Postoperative pain relief and bupivacaine plasma levels during continuous interscalene brachial plexus block

Interscalene brachial plexus block was performed on 40 patients for prophylactic pain relief after shoulder surgery. A dose of 1.25 mg/kg of 0.5% bupivacaine was injected for the block (Group 1) and continued with an infusion of 0.25% bupivacaine 0.25 mg/kg/h (Group 2). If the postoperative analgesia was insufficient, the patients received i.m. oxycodone 0.15 mg/kg. In Group 1, one patient managed without oxycodone supplementation during the 24-h observation period compared with eight patients in Group 2 (P less than 0.01). The rest of the patients received 3.8 +/- 1.6 doses (Group 1) and 2.5 +/- 1.2 doses (Group 2) of oxycodone (P less than 0.05). At 30 min, the mean bupivacaine plasma concentration was 1.0 microgram/ml in Group 1 and 0.9 microgram/ml in Group 2. The mean plasma level of bupivacaine increased from 0.7 microgram/ml after 180 min to 1.1 micrograms/ml (P less than 0.01) after 24 h of infusion, providing some evidence of accumulation during infusion. The dizziness and confusion experienced by three patients could be associated with the local anaesthetic, as they obtained relief after the infusion was stopped.     

Prospective comparison of continuous femoral nerve block with nonstimulating catheter placement versus stimulating catheter-guided perineural placement in volunteers

BACKGROUND AND OBJECTIVES: Stimulating catheter-guided perineural placement may potentially increase the success rate and quality of continuous femoral nerve block as compared with a nonstimulating catheter technique. These hypotheses have not been rigorously tested. METHODS: Twenty volunteers underwent placement of bilateral femoral nerve catheters in this prospective, randomized, double-blind study. For each side, a stimulating needle was advanced until quadriceps contractions were obtained at < or =0.5 mA. On one side, a stimulating catheter was advanced 4 to 5 cm beyond the needle tip while eliciting quadriceps contractions via the catheter. If quadriceps contractions decreased or disappeared, the catheter position was adjusted until quadriceps contractions could be elicited at < or =0.5 mA. On the contralateral side, an identical catheter was advanced 4 to 5 cm beyond the needle tip without attempts to elicit quadriceps contractions via the catheter. After bolus injection of 10 mL lidocaine 1%, ropivacaine 0.2% at 10 mL/h was continuously infused through both catheters for 4 hours. Success of femoral block was defined as loss of sensation to cold and pinprick stimuli. Quality of successful block was determined by tolerance to transcutaneous electrical stimulation and force dynamometry of quadriceps strength. RESULTS: Block success was 100% via the stimulating catheters versus 85% via the nonstimulating catheters (P =.07). Overall tolerance to transcutaneous electrical stimulation (P =.009) and overall depth of motor block (P =.03) was significantly higher in the stimulating catheter-guided femoral nerve blocks. CONCLUSIONS: In this volunteer study, there was no statistically significant difference in block success between the two techniques. However, stimulating catheter-guided placement provided an increased overall quality of continuous femoral perineural blockade. Further studies are needed to verify these observations in the clinical setting.     

Low-volume interscalene brachial plexus block for post-thoracotomy shoulder pain

OBJECTIVES: This study was designed to evaluate the effectiveness of low-volume interscalene brachial plexus block for post-thoracotomy ipsilateral shoulder pain and to compare it with nonsteroidal anti-inflammatory drug treatment. DESIGN: Prospective nonblinded study. SETTING: University hospital. PARTICIPANTS: Sixty adult patients. INTERVENTION: Patients who underwent elective thoracic surgery under combined epidural and general anesthesia, and after surgery were free of incisional pain but complaining of shoulder pain, were included in the study. They were selected in a sequential manner and placed into 2 groups of 30 patients each. Group 1 had a low-volume interscalene brachial plexus block, using 10 mL of bupivacaine 0.5%. Group 2 had an intramuscular injection of diclofenac sodium, 75 mg. MEASUREMENTS AND MAIN RESULTS: Pain was measured during their stay in the postanesthesia care unit (PACU) by using a visual analog score (VAS). Opioids were administered when pain relief was incomplete. Pain intensity was re-estimated the next morning and patient satisfaction was scored. VAS was found to be significantly lower in the low-volume interscalene block group than in the diclofenac group at 30 minutes after treatment and when leaving PACU (p < 0.001 for both). Patients in the interscalene block group stayed longer in the PACU (p = 0.019), and significantly fewer required rescue opioids (p = 0.03). There was no significant difference between the groups in patient satisfaction with the pain treatment. CONCLUSIONS: The authors concluded that low-volume interscalene brachial plexus block is a superior treatment for post-thoracotomy shoulder pain compared with diclofenac injection, although it requires a slightly longer stay in the PACU.     

连续外周神经阻滞用于术后镇痛的研究进展

近年来,术后镇痛逐渐成为人们关注的热点.神经刺激器、超声定位等方法的出现使外周神经定位更加准确,罗哌卡因等新型局麻药的出现使药物的安全性不断提高,患者自控镇痛技术的日趋成熟使术后镇痛更易于管理.基于上述原因,连续外周神经阻滞作为一种镇痛效果好、安全系数高、易于操作的术后镇痛方法,其价值已越来越引起患者和医师的重视.     

Evaluation of an insulated Tuohy needle system for the placement of interscalene brachial plexus catheters

Major shoulder surgery can be extremely painful. Interscalene brachial plexus catheters provide excellent postoperative analgesia but are technically difficult to place. A new insulated Tuohy needle system for plexus catheterisation is now available. This prospective study examined its ease of use and the postoperative analgesia produced by patient-controlled interscalene analgesia with ropivacaine 0.2%. Nineteen patients undergoing major shoulder surgery were studied. Interscalene brachial plexus blocks were performed using a modified Winnie technique with the insulated Tuohy needle and a nerve stimulator. After injection of ropivacaine 0.75% 30-40 ml into the plexus, a catheter was inserted. Block and catheter insertion times were recorded. All 19 patients had successful blocks and had catheters successfully threaded. Catheter infusions provided successful analgesia (visual analogue pain score < 5/10) in 18 patients, with one failure, giving a 95% success rate. Mean [range] catheter insertion time was 3.6 [1-10] min. Decreased block and catheter insertion times were associated with experience with the equipment when comparing the mean (SD) times for the first seven catheters and the last seven catheters inserted (12.1 (4.2) min vs. 7.9 (2.4) min), p < 0.05). It is concluded that the insulated Tuohy needle system for interscalene catheterisation proved easy to use in the hands of someone who had not used it before, and can be recommended.     

The effect of stimulating versus conventional perineural catheters on postoperative analgesia following ultrasound-guided femoral nerve localization

Study Objective

To test the hypothesis that, if the femoral nerve is correctly localized using ultrasound (US) guidance, the type of perineural catheter used has no effect on catheter success.

Design

Randomized controlled trial.

Setting

Post-anesthesia care unit of an academic teaching hospital.

Patients

40 ASA physical status 1, 2, and 3 patients, ages 55-85 years, undergoing elective total knee arthroplasty.

Interventions

All patients received postoperative continuous femoral nerve blocks and a single injection sciatic nerve block. Nerve localization was accomplished using US guidance and electrical nerve stimulation so that the needle tip was visualized deep to the femoral nerve. Patients were randomized to receive either stimulating (Group SC) or nonstimulating catheters (Group NSC) in the usual manner for each device. Catheters were bolused with ropivacaine and an infusion commenced.

Measurements

The primary outcome was quality of analgesia (as measured by a numerical rating scale). Other outcomes included sensory block success rate, number of attempts and time required to localize the needle tip correctly, number of attempts and time required to place the perineural catheter, amount of local anesthetic and opioid use postoperatively, and degree of completion of preset postoperative rehabilitation goals.

Main Results

Quality of analgesia was similar at all time intervals. Rates of successful femoral block (95% vs 80%; P = 0.34) were similar between groups. Time required to position the catheter was greater in Group SC than Group NSC (3.45 ± 2.05 min vs 1.72 ± 0.88 min; P < 0.01).

Conclusions

Ultrasound guidance for needle localization prior to catheter insertion for femoral nerve block results in similar block characteristics between stimulating and nonstimulating catheters. The use of nonstimulating catheters avoids the technical challenges of stimulating catheters and does not require additional helpers.