Network meta-analysis of the analgesic effectiveness of regional anaesthesia techniques for anterior cruciate ligament reconstruction

Anterior cruciate ligament reconstruction can cause moderate to severe acute postoperative pain. Despite advances in our understanding of knee innervation, consensus regarding the most effective regional anaesthesia techniques for this surgical population is lacking. This network meta-analysis compared effectiveness of regional anaesthesia techniques used to provide analgesia for anterior cruciate ligament reconstruction. Randomised trials examining regional anaesthesia techniques for analgesia following anterior cruciate ligament reconstruction were sought. The primary outcome was opioid consumption during the first 24 h postoperatively. Secondary outcomes were: rest pain at 0, 6, 12 and 24 h; area under the curve of pain over 24 h; and opioid-related adverse effects and functional recovery. Network meta-analysis was conducted using a frequentist approach. A total of 57 trials (4069 patients) investigating femoral nerve block, sciatic nerve block, adductor canal block, local anaesthetic infiltration, graft-donor site infiltration and systemic analgesia alone (control) were included. For opioid consumption, all regional anaesthesia techniques were superior to systemic analgesia alone, but differences between regional techniques were not significant. Single-injection femoral nerve block combined with sciatic nerve block had the highest p value probability for reducing postoperative opioid consumption and area under the curve for pain severity over 24 h (78% and 90%, respectively). Continuous femoral nerve block had the highest probability (87%) of reducing opioid-related adverse effects, while local infiltration analgesia had the highest probability (88%) of optimising functional recovery. In contrast, systemic analgesia, local infiltration analgesia and adductor canal block were each poor performers across all analgesic outcomes. Regional anaesthesia techniques that target both the femoral and sciatic nerve distributions, namely a combination of single-injection nerve blocks, provide the most consistent analgesic benefits for anterior cruciate ligament reconstruction compared with all other techniques but will most likely impair postoperative function. Importantly, adductor canal block, local infiltration analgesia and systemic analgesia alone each perform poorly for acute pain management following anterior cruciate ligament reconstruction.     

The Efficacy and Safety of Regional Nerve Blocks in Total Knee Arthroplasty: Systematic Review and Direct Meta-Analysis

BackgroundRegional nerve blocks are widely used in primary total knee arthroplasty (TKA) to reduce postoperative pain and opioid consumption. The purpose of our study was to evaluate the efficacy and safety of regional nerve blocks after TKA in support of the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Management.MethodsWe searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for studies published before March 24, 2020 on femoral nerve block, adductor canal block, and infiltration between Popliteal Artery and Capsule of Knee in primary TKA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of the regional nerve blocks compared to a control, local peri-articular anesthetic infiltration (PAI), or between regional nerve blocks.ResultsCritical appraisal of 1,673 publications yielded 56 publications representing the best available evidence for analysis. Femoral nerve and adductor canal blocks are effective at reducing postoperative pain and opioid consumption, but femoral nerve blocks are associated with quadriceps weakness. Use of a continuous compared to single shot adductor canal block can improve postoperative analgesia. No difference was noted between an adductor canal block or PAI regarding postoperative pain and opioid consumption, but the combination of both may be more effective.ConclusionSingle shot adductor canal block or PAI should be used to reduce postoperative pain and opioid consumption following TKA. Use of a continuous adductor canal block or a combination of single shot adductor canal block and PAI may improve postoperative analgesia in patients with concern of poor postoperative pain control.     

Single-Injection Femoral and Sciatic Nerve Blocks for Pain Control After Total Knee Arthroplasty

This study was designed to evaluate the addition of a single-injection sciatic nerve block to a femoral nerve block for analgesia after total knee arthroplasty. Fifty-seven patients undergoing primary total knee arthroplasty were randomized to receive femoral nerve blockade or a sham block. A subsequent 31 patients received both femoral and sciatic nerve blocks (FSNBs) before general anesthesia. Intravenous morphine use and visual analog pain scale scores were recorded at regular intervals. Femoral and sciatic nerve blocks were placed in less than five minutes, on average. Lower visual analog pain scale scores were noted in both femoral nerve blockade and FSNB groups compared to shams through 48 hours. Morphine use was significantly lower in the FSNB group. Femoral and sciatic nerve block can be placed quickly and consistently in the operating room with improved postoperative pain relief and reduced narcotic consumption.     

Is Continuous Adductor Canal Block Better Than Continuous Femoral Nerve Block After Total Knee Arthroplasty? Effect on Ambulation Ability,Early Functional Recovery and Pain Control: A Randomized Controlled Trial

Total knee arthroplasty is associated with intense, early post-operative pain. Femoral nerve block is known to provide optimal pain relief but reduces the strength of the quadriceps muscle and associated with the risk of falling. Adductor canal block is almost pure sensory blockade with minimal effect on quadriceps muscle strength. We prospectively randomized 100 patients in two groups' continuous adductor and femoral block group. Ambulation ability (Timed up go, 10-m walk, 30 s chair test), time to active SLR, quadsticks, staircase competency, ambulation distance was significantly better (P value < 0.001) in adductor canal group whereas pain scores, opioid consumption showed no significant difference. Adductor canal block provided better ambulation and early functional recovery but without superior analgesia than femoral nerve block post TKA. Level of evidence: Level III, therapeutic study.     

Combination Lower Extremity Nerve Blocks and Their Effect on Postoperative Pain and Opioid Consumption: A Systematic Review

The purpose of this study was to perform a systematic review of the literature examining postoperative outcomes following single site and combined peripheral nerve blocks (PNBs), including (1) sciatic and femoral nerve, (2) popliteal and saphenous nerve, and (3) popliteal and ankle nerve, during elective foot and ankle surgery. We hypothesized that combination blocks would decrease postoperative narcotic consumption and afford more effective postoperative pain control as compared to general anesthesia, spinal anesthesia, or single site PNBs. A review of the literature was performed according to the PRISMA guidelines. Medline, EMBASE, and the Cochrane Library were searched from January 2009 to October 2019. We identified studies by using synonyms for “foot,” “ankle” “pain management,” “opioid,” and “nerve block.” Included articles explicitly focused on elective foot and ankle procedures performed under general anesthesia, spinal anesthesia, PNB, or with some combination of these techniques. PNB techniques included femoral, adductor canal, sciatic, popliteal, saphenous, and ankle blocks, as well as blocks that combined multiple anatomic sites. Outcomes measured included postoperative narcotic consumption as well as patient-reported efficacy of pain control. Twenty-eight studies encompassing 6703 patients were included. Of the included studies, 57% were randomized controlled trials, 18% were prospective comparison studies, and 25% were retrospective comparison studies. Postoperative opioid consumption and postoperative pain levels were reduced over the first 24 to 48 hours with the use of combined PNBs when compared with single site PNBs, both when used as primary anesthesia or when used in concert with general anesthesia either alone or combined with systemic/local anesthesia in the first 24 to 48 hours following surgery. Studies demonstrated higher reported patient satisfaction of postoperative pain control in patients who received combined PNB. Nine of 14 (64%) studies reported no neurologic related complications with an overall reported rate among all studies ranging from 0% to 41%. Our study identified substantial improvement in postoperative pain levels, postoperative opioid consumption, and patient satisfaction in patients receiving PNB when compared with patients who did not receive PNB. Published data also demonstrated that combination PNB are more effective than single-site PNB for all data points. Notably, the addition of a femoral nerve block to a popliteal nerve block during use of a thigh tourniquet, as well as addition of either saphenous or ankle blockade to popliteal nerve block during use of calf tourniquet, may increase overall block effectiveness. Serious complications including neurologic damage following PNB administration are rare but do exist.     

Comparing the Effects of Single Shot Sciatic Nerve Block Versus Posterior Capsule Local Anesthetic Infiltration on Analgesia and Functional Outcome After Total Knee Arthroplasty : A Prospective,Randomized, Double-Blinded,Controlled Trial

Peripheral nerve blocks appear to provide effective analgesia for patients undergoing total knee arthroplasty. Although the literature supports the use of femoral nerve block, addition of sciatic nerve block is controversial. In this study we investigated the value of sciatic nerve block and an alternative technique of posterior capsule local anesthetic infiltration analgesia. 100 patients were prospectively randomized into three groups. Group 1: sciatic nerve block; Group 2: posterior local anesthetic infiltration; Group 3: control. All patients received a femoral nerve block and spinal anesthesia. There were no differences in pain scores between groups. Sciatic nerve block provided a brief clinically insignificant opioid sparing effect. We conclude that sciatic nerve block and posterior local anesthetic infiltration do not provide significant analgesic benefits.     

A comparison of pre‐operative nerve stimulator‐guided femoral nerve block and fascia iliaca compartment block in patients with a femoral neck fracture

We undertook a randomised, controlled trial to compare the analgesic efficacy and opioid sparing effect of nerve stimulator‐guided femoral nerve block with fascia iliaca compartment block in patients awaiting surgery for fractured neck of femur. Ten‐centimetre visual analogue pain scores were measured before and 2 h after the block and opioid consumption was recorded in the 12‐h period after the block. One hundred and ten patients were randomly assigned. Femoral nerve block provided superior pre‐operative analgesia for fractured neck of femur compared with fascia iliaca compartment block. The difference in the mean reduction of pain score after the block was 0.9 (95% CI 0–1.8); p = 0.047. Patients receiving a femoral nerve block required less morphine after the block than those receiving fascia iliaca compartment block (p = 0.041).     

The adductor canal catheter and interspace between the popliteal artery and the posterior capsule of the knee for total knee arthroplasty

Analgesia for total knee arthroplasty (TKA) is not a new topic; however, some newer approaches to peripheral nerve blocks for control of postoperative pain have been developed. The femoral nerve block plus or minus a sciatic nerve block has been shown to provide effective analgesia, but not without some degree of motor block. The adductor canal block provides analgesia not inferior to a femoral with less motor weakness, and a continuous catheter technique can be used to prolong its effects. Blocking the sciatic nerve has been a subject of controversy, in part because of the motor weakness but also because of the inclusion of the common peroneal nerve, a nerve that can potentially be damaged by TKA. An infiltration of the interspace between the popliteal artery and the capsule of the posterior knee, provides analgesia for the posterior knee without motor effects or common peroneal block. The combination of an adductor canal catheter and an interspace between the popliteal artery and the capsule of the posterior knee provides a balance of effective postoperative analgesia and preservation of motor function, ultimately shortening length of stay following TKA.     

Combined preoperative femoral and sciatic nerve blockade improves analgesia after anterior cruciate ligament reconstruction: a randomized controlled clinical trial

Study objectiveTo compare preoperative femoral (FNB) with combined femoral and sciatic nerve block (CFSNB) in patients undergoing arthroscopic anterior cruciate ligament (ACL) reconstruction.DesignProspective, randomized clinical trial.SettingAmbulatory surgery center affiliated with an academic medical center.PatientsSixty-eight American Society of Anesthesiology physical status I and II patients undergoing arthroscopic ACL reconstruction.InterventionsSubjects randomized to the CFSNB group received combined femoral and sciatic nerve blocks preoperatively, whereas patients randomized to the FNB group only received femoral nerve block preoperatively. Both groups then received a standardized general anesthetic with a propofol induction followed by sevoflurane or desflurane maintenance. Intraoperative pain was treated with fentanyl. Pain in the postanesthesia care unit (PACU) was treated with ketorolac and opiates. Patients with significant pain despite ketorolac and opiates could receive a rescue nerve block.MeasurementsOur primary outcome variable was highest Numeric Rating Scale (NRS) pain score in PACU. NRS pain scores, opioid consumption, opioid adverse effects, and patient satisfaction were assessed perioperatively until postoperative day 3.Main resultsThe highest PACU NRS pain score was significantly higher in the FNB group compared with the CFSNB group (7 [3-10] vs 5 [0-10], P = .002). The FNB group required significantly larger doses of opioids perioperatively (31.8 vs 19.8 mg intravenous morphine equivalents, P < .001). PACU length of stay was significantly longer in the FNB group (128.2 vs 103.1 minutes, P = .006). There was no significant difference in opioid consumption, pain scores, or patient satisfaction on postoperative days 1-3 between groups.ConclusionsPreoperative CFSNB for arthroscopic ACL reconstruction improves analgesia, decreases opioid consumption perioperatively, and decreases PACU length of stay when compared with FNB alone.     

Editorial Commentary: Femoral Nerve Block: Don’t Kill the Motor Branch

Femoral nerve block is commonly used for pain control after knee surgery and helps to reduce the need for opioids in the early postoperative period. The potential disadvantage is blockage of the motor branch of the femoral nerve, resulting in quadriceps weakness and reduced strength by up to 50%. Adductor canal nerve block is a possible alternative resulting in less muscle weakness. The rationale behind adductor canal nerve block is blockage of the saphenous nerve and part of the obturator nerve, providing reliable and adequate pain relief.     

Lower limb nerve blocks

The proliferation of ultrasound use is changing the approach to regional anaesthesia of the lower limb. Techniques are being developed that provide high-quality postoperative analgesia while minimizing associated motor block that may impair mobilization. Regional anaesthetic techniques also provide significant opioid-sparing benefits (e.g. less sedation, nausea and urinary retention) that are key principles of current enhanced recovery protocols. Ultrasound-guided nerve localization offers several potential advantages when performing femoral, adductor canal, sciatic and ankle blocks; however, neurostimulation remains a useful and widely used aid to lower limb regional anaesthesia practice.     

Lower limb nerve blocks

The proliferation of ultrasound use is changing the approach to regional anaesthesia of the lower limb. Techniques are being developed that provide high-quality postoperative analgesia while minimizing associated motor block that may impair mobilization. Regional anaesthetic techniques also provide significant opioid-sparing benefits (e.g. less sedation, nausea and urinary retention) that are key principles of current enhanced recovery protocols. Ultrasound-guided nerve localization offers several potential advantages when performing femoral, adductor canal, sciatic and ankle blocks; however, neurostimulation remains a useful and widely used aid to lower limb regional anaesthesia practice.     

Comparison of Regional Anesthesia Timing on Pain,Opioid Use,and Postanesthesia Care Unit Length of Stay in Patients Undergoing Open Reduction and Internal Fixation of Ankle Fractures

Regional nerve blocks are an effective method of managing acute pain associated with surgery. The relative benefit of preoperative versus postoperative peripheral nerve blocks is not entirely clear. The primary aim of this study was to determine differences in pain scores in patients undergoing preoperative block versus postoperative block versus no block. We hypothesized that patients receiving preoperative blocks would have reduced pain scores and decreased opioid use in the immediate postoperative period. We conducted a retrospective cohort analysis of 302 consecutive patients undergoing unilateral open reduction and internal fixation of ankle fracture under general anesthesia. We identified 3 groups: preoperative block, postoperative block, or no block. Data obtained from our electronic medical records included demographic information, postanesthesia care unit length of stay, pain scores obtained preoperatively, upon arrival to the postanesthesia care unit, and upon discharge from the postanesthesia care unit as well as intraoperative and postanesthesia care unit opioid utilization. Patients receiving preoperative block had significantly lower pain scores, less intraoperative or postanesthesia care unit opioid use, and shorter postanesthesia care unit dwell time compared with patients receiving postoperative block or no block. Preoperative popliteal sciatic and adductor canal blocks in patients undergoing ankle fracture surgery appears to be more effective than either postoperative block or no block.     

A comparison of analgesic techniques for total knee arthroplasty: A network meta-analysis

Study objectiveThere is no established analgesic method for postoperative total knee arthroplasty. We comprehensively compared the analgesic methods for postoperative total knee arthroplasty.DesignA network meta-analysis of randomised controlled trials was used to compare 18 interventions, which were ranked by six outcome indices, to select the best modality.SettingPostoperative recovery room and inpatient ward.Patients98 randomised controlled trials involving 7452 patients (ASA I-III) were included in the final analysis.InterventionsStudies that included the use of at least one of the following 12 nerve block(fascia iliaca compartment block (FIB), FNB, cFNB, single femoral nerve block (sFNB), adductor canal block (ACB), sciatic nerve block (SNB), obturator nerve block (ONB), continuous posterior lumbar plexus block (PSOAS), FNB + SNB, ACB + LIA, FNB + LIA, PCA + FNB).MeasurementsPain intensity was compared using Visual Analogue Scale (VAS). Also, postoperative complications, function score, hospital length of stay, morphine consumption and patient satisfaction were measured.Main resultsFor visual analogue scale scores, continuous femoral nerve block (FNB) and FNB + sciatic nerve block (SNB) were the the most effective interventions. For reducing postoperative complications, fascia iliaca compartment block, FNB, SNB, and obturator nerve block showed the best results. For reducing postoperative morphine consumption, adductor canal block (ACB) + local infiltration analgesia (LIA) and FNB + SNB were preferred. For function scores (range of motion, Timed-Up-and-Go test), ACB and LIA were optimal choices. For reducing hospital length of stay and patient satisfaction, ACB + LIA and FNB + LIA were best, respectively.ConclusionsPeripheral nerve block, especially FNB and ACB, is a better option than other analgesic methods, and its combination with other methods can be beneficial. Peripheral nerve block is a safe and effective postoperative analgesia method. However, our findings can only provide objective evidence. Clinicians should choose the treatment course based on the individual patient's condition and clinical situation.     

周围神经阻滞后爆发痛的研究进展

周围神经阻滞是围术期控制疼痛和减少阿片类药物使用的重要手段。然而，以周围神经阻滞后痛觉过敏为特征的术后爆发痛可能会减少这种方式的总体获益，它会对镇痛药物总用量、患者整体满意度和术后恢复产生明显影响，也可能引起心血管和肺部并发症，对患者的预后产生负面影响。了解周围神经阻滞后爆发痛的特征、危险因素和防治策略对于有效利用周围神经阻滞起到重要作用。     

The value of adding sciatic block to continuous femoral block for analgesia after total knee replacement

BACKGROUND AND OBJECTIVES: The benefit of adding a sciatic nerve block to the femoral block to improve analgesia after total knee replacement is controversial. The aim of this study is to address this controversy in a prospective, comparative, and randomized study. METHODS: Patients were allocated randomly to receive a continuous femoral nerve block or continuous blocks of both the femoral and sciatic nerves. Stimulating catheters were used in all cases. A loading dose of 15 mL ropivacaine 0.75% was injected into each catheter, followed by administration of ropivacaine 0.2% (2-5 mL/h infusion via the femoral catheter; bolus 10 mL repeated every 12 hours in the sciatic catheter). The primary outcome was visual analog scale (VAS) scores (0 = no pain, 100 mm = worst pain) in postanesthesia care unit and in the 48-hour period after surgery. The secondary outcomes were amplitude of knee flexion, morphine consumption, and occurrence of postoperative nausea and vomiting (PONV). RESULTS: The VAS scores at rest were significantly higher when there was only continuous femoral nerve block than when there was both continuous femoral and sciatic nerve blocks. This difference progressively decreased and disappeared at 36 hours after surgery. The combined femoral and sciatic blocks decreased the morphine consumption by 81% and significantly decreased the occurrence of PONV. CONCLUSION: During the 36 hours immediately after total knee replacement, the combination of continuous femoral and sciatic nerve blocks improves analgesia while decreasing morphine consumption and PONV.     

Adding a selective obturator nerve block to the parasacral sciatic nerve block: an evaluation

Our aim was to objectively evaluate the efficacy of obturator nerve anesthesia after a parasacral block. Patients scheduled for knee surgery had a baseline adductor strength evaluation. After a parasacral block with 30 mL 0.75% ropivacaine, sensory deficit in the sciatic distribution (temperature discrimination) and adductor strength were assessed at 5-min intervals. Patients with an incomplete sensory block (defined as a temperature discrimination score of less than 2 in the 3 cutaneous distributions of the sciatic nerve tested) 30 min after the parasacral block were excluded from the study. Subsequently, a selective obturator block was performed with 7 mL 0.75% ropivacaine and adductor strength was reassessed at 5 min intervals for 15 min. Finally, a femoral block was performed using 10 mL 0.75% ropivacaine. Patient discomfort level during each block was assessed using a visual analog scale (VAS). Thirty-one patients completed the study. Five patients were excluded as a result of inadequate sensory block in the sciatic distribution 30 min after the parasacral block (success rate of 89%). Thirty min after the parasacral block, adductor strength decreased by 11.3% +/- 7% compared with baseline (85 +/- 24 versus 97 +/- 28 mm Hg, P = 0.002). Fifteen min after the obturator nerve block, adductor muscle strength decreased by an additional 69% +/- 7% (16.6 +/- 15 versus 85 +/- 24 mm Hg, P < 0.0001). VAS scores were similar for all blocks (26 +/- 19, 28 +/- 24, and 27 +/- 19 mm for parasacral, obturator, and femoral respectively). Four parasacral blocks were simulated in 2 fresh cadavers using 30 mL of colored latex solution. The spread of the die in relation to the obturator nerve was assessed. Injection of 30 mL colored latex into cadavers resulted in spread of the injectate restricted to the sacral plexus. These findings demonstrate the unreliability of parasacral block to achieve anesthesia of the obturator nerve. A selective obturator block should be considered in the clinical setting when this is desirable.     

Effect of preemptive multimodal analgesia for arthroscopic knee ligament repair

BACKGROUND AND OBJECTIVES: Administration of analgesic medication before surgery, rather than at the completion of the procedure, may reduce postoperative pain. Similarly, administration of multiple analgesics, with different mechanisms of action, may provide improved postoperative pain control and functional recovery. The purpose of our study was to compare pain scores and intravenous opioid consumption after outpatient anterior cruciate ligament (ACL) reconstruction in patients who received a multimodal drug combination (intravenous [IV] ketorolac, intra-articular morphine/ropivacaine/epinephrine, and femoral nerve block with ropivacaine) either before surgery or immediately at the completion of the surgical procedure. METHODS: Forty patients presenting for same-day arthroscopic ACL repair using a semitendinosis tendon graft were included in this study. The patients were randomized to receive the following drugs either 15 minutes before skin incision or immediately after skin closure: (1) Ketorolac 30 mg IV. (2) Intra-articular injection of 20 mL ropivacaine 0.25% + morphine 2 mg and epinephrine 1:200,000. (3) Femoral nerve block with 20 mL ropivacaine 0.25%. Verbal pain scores were obtained in the postanesthesia care unit (PACU) and on postoperative days 1, 3, and 7. IV patient controlled analgesia (PCA) morphine consumption in the PACU was also recorded. RESULTS: Verbal pain rating scores were lower in group I (preemptive) for 2.0 hours after arrival in the PACU. There was no difference between groups in pain scores on postoperative days 1, 3, and 7. Mean IV PCA morphine consumption in the PACU was lower in group I (6.4 mg) versus group II (12.3 mg), P <.05. CONCLUSION: Preemptive, multimodal administration of our 3-component analgesic drug combination resulted in lower pain scores during the initial stay in the PACU unit and lower consumption of IV PCA morphine in the PACU. However, pain scores were similar in both groups on postoperative days 1, 3, and 7; thus, there was no measurable long-term advantage associated with preemptive multimodal drug administration.