Ultrasound-guided adductor canal block for arthroscopic medial meniscectomy: a randomized, double-blind trial.

PURPOSE: The saphenous nerve block using a landmark-based approach has shown promise in reducing postoperative pain in patients undergoing arthroscopic medial meniscectomy. We hypothesized that performing an ultrasound-guided adductor canal saphenous block as part of a multimodal analgesic regimen would result in improved analgesia after arthroscopic medial meniscectomy. METHODS: Fifty patients presenting for ambulatory arthroscopic medial meniscectomy under general anesthesia were prospectively randomized to receive an ultrasound-guided adductor canal block with 0.5% ropivacaine or a sham subcutaneous injection of sterile saline. Our primary outcome was resting pain scores (numerical rating scale; NRS) upon arrival to the postanesthesia care unit (PACU). Secondary outcomes included NRS at six hours, 12 hr, 18 hr, and 24 hr; postoperative nausea; and postoperative opioid consumption. RESULTS: There was a statistically significant difference in mean NRS pain scores upon arrival to the PACU (P = 0.03): block group NRS = 1.71 (95% confidence interval [CI] 0.73 to 2.68) vs sham group NRS = 3.25 (95% CI 2.27 to 4.23). Cumulative opioid consumption (represented in oral morphine equivalents) over 24 hr was 71.8 mg (95% CI 56.5 to 87.2) in the sham group vs 44.9 mg (95% CI 29.5 to 60.2) in the block group (P = 0.016). CONCLUSIONS: An ultrasound-guided block at the adductor canal as part of a combined multimodal analgesic regimen significantly reduces resting pain scores in the PACU following arthroscopic medial meniscectomy. Furthermore, 24-hr postoperative opioid consumption and pain scores were also reduced.

Contemporary Anesthetic Evaluation and Management for Electroconvulsive Therapy.

Electroconvulsive therapy (ECT) is a medical treatment most often used in patients with severe major depression that has not responded to other treatments. ECT is also indicated for patients with other severe psychiatric conditions, including bipolar disorder, schizophrenia, schizoaffective disorders, catatonia, and neuroleptic malignant syndrome. Contemporary "modified ECT" involves inducing general anesthesia with neuromuscular blockade before inducing the therapeutic seizure. The goal of this review is to combine an evidence-based update with the experience of the author's institution to provide a practical approach to anesthetic care for the patient undergoing ECT.

Motor-sparing nerve blocks for total knee replacement: A scoping review.

STUDY OBJECTIVE: This scoping review investigates the optimal combination of motor-sparing analgesic interventions for patients undergoing total knee replacement (TKR). DESIGN: Scoping review. INTERVENTION: MEDLINE, EMBASE and CINAHL databases were searched (inception-last week of May 2020). Only trials including motor-sparing interventions were included. Randomized controlled trials lacking prospective registration and blinded assessment were excluded. MAIN RESULTS: The cumulative evidence suggests that femoral triangle blocks outperform placebo and periarticular infiltration. When combined with the latter, femoral triangle blocks are associated with improved pain control, higher patient satisfaction and decreased opioid consumption. Continuous femoral triangle blocks provide superior postoperative analgesia compared with their single-injection counterparts. However, these benefits seem less pronounced when perineural adjuvants are used. Combined femoral triangle-obturator blocks result in improved analgesia and swifter discharge compared with femoral triangle blocks alone. CONCLUSIONS: The optimal analgesic strategy for TKR may include a combination of different analgesic modalities (periarticular infiltration, femoral triangle blocks, obturator nerve block). Future trials are required to investigate the incremental benefits provided by local anesthetic infiltration between the popliteal artery and the capsule of the knee (IPACK), popliteal plexus block and genicular nerve block.

Lower extremity regional anesthesia: essentials of our current understanding.

The advent of ultrasound guidance has led to a renewed interest in regional anesthesia of the lower limb. In keeping with the American Society of Regional Anesthesia and Pain Medicine's ongoing commitment to provide intensive evidence-based education, this article presents a complete update of the 2005 comprehensive review on lower extremity peripheral nerve blocks. The current review article strives to (1) summarize the pertinent anatomy of the lumbar and sacral plexuses, (2) discuss the optimal approaches and techniques for lower limb regional anesthesia, (3) present evidence to guide the selection of pharmacological agents and adjuvants, (4) describe potential complications associated with lower extremity nerve blocks, and (5) identify informational gaps pertaining to outcomes, which warrant further investigation.

The effect of single-injection femoral nerve block versus continuous femoral nerve block after total knee arthroplasty on hospital length of stay and long-term functional recovery within an established clinical pathway.

Total knee arthroplasty (TKA) may result in severe pain, and single-injection femoral nerve blocks (SFNB) have been demonstrated to have a limited duration of analgesia. Continuous femoral nerve blocks (CFNB) can prolong the analgesic duration of SFNB. We prospectively randomized 36 patients undergoing TKA to CFNB versus SFNB and evaluated the effect on hospital length of stay (LOS) as the primary outcome within a standardized clinical pathway. Secondary outcomes included visual analog scale (VAS) pain scores, opioid consumption, and long-term functional recovery at 12 wk. Mean VAS resting scores were significantly lower among patients who received CFNB versus SFNB: first day (1.7 vs 3.3 [P = 0.002]) and second day (0.9 vs 3.2 [P < 0.0001]) after surgery. Mean maximal VAS scores during physical therapy were significantly lower among patients who received CFNB versus SFNB: first day (4.7 vs 6.3 [P = 0.01]) and second day (3.9 vs 6.1 [P = 0.0005]) after surgery. Mean oxycodone consumption was significantly lower among patients who received CFNB versus SFNB: 15 mg versus 40 mg (P = or < 0.0001) on the first day after surgery; 20 mg versus 43 mg (P = 0.0004) on the second day after surgery. There was no difference in hospital LOS (3.8 vs 3.9 days) or long-term functional recovery (117 degrees versus 113 degrees knee flexion at 12 wk) between the two groups. The lack of effect provided by increased duration of analgesia (from CFNB) after TKA may now have minimal impact on hospital LOS and long-term functional recovery in the contemporary healthcare environment within the United States.

Concurrent expansion of plasma volume and left ventricular end-diastolic volume in patients after rapid infusion of 5% albumin and lactated Ringer's solution.

STUDY OBJECTIVE: To examine the effects of plasma volume expansion on plasma volume, left ventricular end-diastolic volume (LVEDV), and cardiac index (CI) after rapid fluid infusion, as knowledge of the degree of concordance between plasma and cardiac preload expansion could optimize LVEDV expansion without administering excessive fluid. DESIGN: Randomized, double-blinded study. SETTING: Academic community hospital. PATIENTS: 20 patients undergoing elective coronary artery bypass surgery. INTERVENTIONS: Patients were administered either 5% albumin (5 mL/kg) or lactated Ringer's solution (25 mL/kg) over 30 minutes, just before incision. MEASUREMENTS: Serial measurements of plasma volume, LVEDV by transesophageal echocardiography, and CI were recorded. MAIN RESULTS: Albumin expanded plasma volume and LVEDV to a similar degree (11.3% and 13.2%). In contrast, lactated Ringer's solution increased plasma volume more than LVEDV (21.7% vs 14.4%; P = 0.0005). Increased LVEDV significantly but poorly correlated with increased CI (r(2) = 0.2, P < 0.0001) for both fluids. However, LVEDV expansion was brief and returned to baseline or less within 30 minutes for both fluids despite continued plasma volume expansion and increased CI. Correspondingly, rates of decline from peak expansion were significantly faster for LVEDV than plasma volume expansion for both albumin (-1.9% + 1.9%/min vs -0.1% + 0.1%/min; P = 0.0008) and lactated Ringer's (-1.1% + 0.8%/min vs -0.4% + 0.2%/min; P = 0.006). CONCLUSIONS: Intravenous fluids increased LVEDV to a lesser extent and duration than did plasma volume expansion. Monitoring of LVEDV was a poor guide for fluid administration to maximize CI.

Evidence Basis for Ultrasound Guidance for Lower-Extremity Peripheral Nerve Block: Update 2016.

This article reviews and summarizes randomized controlled studies that have investigated ultrasound guidance (USG) for lower-extremity peripheral nerve blocks in comparison with other peripheral nerve localization techniques and those that compared different ultrasound-guided techniques investigating optimal perineural local anesthetic distribution patterns.Thirty-four studies met the inclusion criteria (minimum Jadad score 3), and 10 additional studies directly compared USG with peripheral nerve stimulation, and 5 additional studies directly compared USG with landmark-based field blocks. Fourteen studies compared different local anesthetic distribution parameters.Analysis of the literature supports the use of USG for decreased block performance time, decreased block onset time, increased rate of complete sensory block, and increased analgesic efficacy. Ultrasound was never inferior to peripheral nerve stimulation. The research focus has evolved during the last 5 years into investigating optimal ultrasound-guided techniques.

Local Anesthetic-Induced Myotoxicity After Continuous Adductor Canal Block.

OBJECTIVE: Local anesthetic-induced myotoxicity occurs consistently in animal models, yet is reported rarely in humans. Herein, we describe 3 sentinel cases of local anesthetic myotoxicity after continuous adductor canal block (ACB). CASE REPORT: Three patients underwent total knee arthroplasty that was managed with subarachnoid block plus ACB induced with 1.5% lidocaine or 1.5% mepivacaine bolus followed by 0.2% ropivacaine at 8 mL/h. Although initial postoperative recovery was normal, each patient on either postoperative day 1 or 2 developed progressive, profound weakness of the quadriceps muscles. Clinical course, imaging, and neurophysiologic studies were consistent with myositis. The patients experienced partial to full functional recovery over the ensuing weeks to months. CONCLUSIONS: Clinically apparent local anesthetic-induced myotoxicity has been documented rarely in humans undergoing non-ophthalmic surgery. We report 3 sentinel cases associated with continuous ACB.

The Second American Society of Regional Anesthesia and Pain Medicine Evidence-Based Medicine Assessment of Ultrasound-Guided Regional Anesthesia: Executive Summary.

OBJECTIVES: In 2009 and again in 2012, the American Society of Regional Anesthesia and Pain Medicine assembled an expert panel to assess the evidence basis for ultrasound guidance as a nerve localization tool for regional anesthesia. METHODS: The 2012 panel reviewed evidence from the first advisory but focused primarily on new information that had emerged since 2009. A new section was added regarding the accuracy and reliability of ultrasound for determining needle-to-nerve proximity. Jadad scores are used to rank study quality. Grades of recommendations consistent with their level of evidence are provided. RESULTS: The panel offers recommendations based on synthesis and analysis of literature related to (1) the technical capabilities of ultrasound equipment and its operators, (2) comparison of ultrasound to other methods of nerve localization with regard to block characteristics, (3) comparison of block techniques where ultrasound is the sole nerve localization modality, and (4) major complications. Assessment of evidence strength and recommendations are made for upper- and lower-extremity, truncal, neuraxial, and pediatric blocks. CONCLUSIONS: Scientific evidence from the past 5 years has clarified and strengthened our understanding of ultrasound-guided regional anesthesia as a nerve localization tool. High-level evidence supports ultrasound guidance contributing to superior characteristics with selected blocks, although absolute differences with the comparator technique are often relatively small (especially for upper-extremity blocks). The clinical meaningfulness of these differences is likely of variable importance to individual practitioners. The use of ultrasound significantly reduces the risk of local anesthetic systemic toxicity as well as the incidence and intensity of hemidiaphragmatic paresis, but has no significant effect on the incidence of postoperative neurologic symptoms. WHAT'S NEW IN THIS UPDATE?: This evidence-based assessment of ultrasound-guided regional anesthesia reviews findings from our 2010 publication and focuses on new meta-analyses, randomized controlled trials, and large case series published since 2009. New to this exercise is an in-depth analysis of the accuracy and reliability of ultrasound guidance for identifying needle-to-nerve relationships. This version no longer addresses ultrasound for interventional pain medicine procedures, because the growth of that field demands separate consideration. Since our 2010 publication, new information has either supported or strengthened our original conclusions. There is no evidence that ultrasound is inferior to alternative nerve localization methods.

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.

Peripheral nerve blocks for ambulatory surgery.

Peripheral nerve blocks (PNBs) provide significant improvement in postoperative analgesia and quality of recovery for ambulatory surgery. Use of continuous PNB techniques extend these benefits beyond the limited duration of single-injection PNBs. The use of ultrasound guidance has significantly improved the overall success, efficiency, and has contributed to the increased use of PNBs in the ambulatory setting. More recently, the use of ultrasound guidance has been demonstrated to decrease the risk of local anesthetic systemic toxicity. This article provides a broad overview of the indications and clinically useful aspects of the most commonly used upper and lower extremity PNBs in the ambulatory setting. Emphasis is placed on approaches that can be used for single-injection PNBs and continuous PNB techniques.

Evidence-based medicine for ultrasound-guided regional anesthesia.

Available evidence favoring the use of ultrasound for regional anesthesia is reviewed, updated, and critically assessed. Important outcome advantages include decreased time to block onset; decreased risk of local anesthetic systemic toxicity; and, depending on the outcome definition, increased block success rates. Ultrasound guidance, peripheral nerve blocks, and central neuraxial blocks are discussed.