Regional Anesthesia and Pain Medicine最新文献

Introduction: Propofol, a commonly used intravenous anesthetic induction agent, frequently produces pain on injection, with an incidence ranging from 28% to 91%. This study aimed to compare the effect of low-dose ketamine and a pressure vibration mechanical device with placebo in reducing pain during propofol injection in patients undergoing elective surgery.

Methods: In this randomized, double-blind, placebo-controlled trial, 300 adults were allocated to pressure vibration (Group V), low-dose ketamine (Group K), or saline placebo (Group P); 275 patients completed the study and were analyzed (92, 91, and 92 patients, respectively). Group P received 5 mL 0.9% saline, Group K ketamine 50 µg/kg diluted in 5 mL saline, and Group V saline with an activated pressure vibration device applied proximal to the intravenous cannula, each administered over 1 min. Propofol 2 mg/kg was infused, with the first 25% delivered at 600 mL/hour, and pain assessed using the McCrirrick and Hunter verbal rating score. The primary outcome was pain on propofol injection. Continuous variables were analyzed using one-way analysis of variance or Kruskal-Wallis tests, categorical variables with χ² tests, with Bonferroni correction applied for multiple primary outcome comparisons.

Results: Among 275 analyzed patients, the incidence of no pain was highest in the pressure vibration device group 51.1%; 95% CI 42.4% to 59.8% compared with placebo 30.4%; 95% CI 21.0% to 39.8% and ketamine 33.0%; 95% CI 23.3% to 42.6%; (p=0.001). Severe pain was more frequent in the placebo group (18.5%; 95% CI 10.5% to 26.4%) than in the ketamine (5.5%; 95% CI 0.8% to 10.2%) and vibration groups (4.3%; 95% CI 0.2% to 8.5%; (p=0.001). Recall of injection pain at 1 week was significantly higher with placebo compared with ketamine and vibration device (55.4%, 37.4%, and 26.1%, respectively; p<0.001). Hemodynamic variables and adverse events were comparable across groups.

Conclusion: The pressure vibration mechanical device significantly reduced the incidence and severity of propofol injection pain compared with placebo and was at least as effective as low-dose ketamine. Pain recall at 1 week was higher with placebo. This device provides an effective, reusable, non-pharmacological alternative without drug-related adverse effects.

Trial registration number: CTRI/2022/12/048300.

Background: Corticosteroid injections (CSIs) are widely employed in facet and sacroiliac joint pain. Similar to CSIs at other sites (peripheral nerve blocks, joints, epidural), these injections are associated with potential adverse events. These multisociety consensus recommendations aim to develop evidence-based statements and recommendations on the safe use of CSIs in facet joint and sacroiliac joint injections.

Methods: Development of the consensus recommendations was approved by the American Society of Regional Anesthesia and Pain Medicine Board of Directors and several other societies that agreed to participate. The scope of statements and recommendations was agreed on to include safety of the injection technique (landmark-guided, ultrasound, or radiology-aided injections); effect of the addition of the corticosteroid on effectiveness (vs local anesthetic or saline); and adverse events related to the injection. Experts were assigned topics to perform a comprehensive literature review and draft statements and recommendations, which were refined and voted for consensus (>75% agreement) using a modified Delphi process. A modified version of the US Preventive Services Task Force grading of evidence and strength of recommendation was followed.

Results: All statements and recommendations were approved by all participants after four rounds of discussion. The Practice Guidelines Committees and Boards of Directors of the participating societies also approved all statements and recommendations. Injection of corticosteroid into the facet joint in patients with joint inflammation may relieve pain and improves function. Intra-articular, extra-articular (periarticular), and combined administration are effective for sacroiliac joint injections. No dose-response studies exist, but CSIs containing 10 mg of methylprednisolone or triamcinolone per facet joint and 40 mg per sacroiliac joint (SIJ) (or their respective pharmacologic equivalents) are reasonable.

Conclusions: In this practice recommendation, we provide statements and recommendations on facet and sacroiliac joint CSIs, the optimal doses, and intervals and criteria for repeating the CSIs in patients with facet joint and sacroiliac joint pain.

Background: Joint replacement is standard of care for chronic knee osteoarthritis, but can cause persistent postsurgical pain. Radiofrequency denervation helps treat chronic knee pain, though its effectiveness is lower in patients with knee arthroplasty than in those with native knees. Our goal was to compare genicular nerve targets in native and prosthetic cadaveric knees and see if targets need modification after arthroplasty.

Methods: 10 native and 10 prosthetic knees from deceased donors underwent latex arterial injection and detailed dissection of the genicular nerves, comparing their origin, course, target points, diameter, and proximity with arterial blood vessels.

Results: Minimal differences among genicular nerve targets were observed between the two groups. The prosthetic knees had fibrotic adhesions of the infrapatellar branch of the saphenous nerve (IPBSN) due to previous surgery, potentially causing postsurgical neuromas and neuritis. The average nerve diameter at target points was smaller in prosthetic than native knees. The distance from the target point to the joint line was shorter for the superomedial genicular nerve in the prosthetic knee group (4.00±0.43 cm vs 4.53±0.75 cm, p=0.005). Nine native and eight prosthetic knees lacked an arterial branch near the target point of the superolateral genicular nerve (SLGN).

Conclusion: Prosthetic knees share comparable genicular nerve anatomic locations with native knees but exhibit smaller nerve diameters and fibrosis of the IPBSN. The absence of a nearby arterial branch to the SLGN may reduce ultrasound targeting accuracy. Anatomical differences alone, however, do not fully explain the diminished pain relief observed after radiofrequency ablation.

Gastric ultrasound is a well-established point-of-care ultrasound (PoCUS) application that aids clinicians in the assessment of gastric content and risk of aspiration at the bedside. In recent years, with the increasing use of Glucagon-like-Peptide 1 (GLP-1) receptor agonists the utility of gastric PoCUS has been endorsed by several professional societies, particularly when fasting status is uncertain. However, 2%-5% of gastric ultrasound exams can yield indeterminate findings due to various reasons. In this educational article, we aim to highlight common pitfalls that can lead to misinterpretation of gastric ultrasound findings and offer troubleshooting strategies to enhance image acquisition and interpretation. Finally, we suggest alternative scanning planes that may be considered when the standard approach is not feasible or fails to provide sufficient information.

Introduction: Preclinical and clinical studies have shown enhanced analgesia when some adjuvant medications are combined with local anesthetics during peripheral nerve (PN) blockade. However, the effects of many adjuvants on individual PN fibers, that is, A-alpha/beta, A-delta, and C, remain poorly characterized.

Methods: Using ex vivo rat sciatic nerve electrophysiology, changes in action potential amplitude (AMP) and area under the curve (AUC) for A-alpha/beta, A-delta, and C fibers were used to determine the half-maximal effective concentrations (EC50) for four adjuvants (dexmedetomidine, magnesium, epinephrine, ketorolac) with and without bupivacaine. At a clinically relevant "high" concentration, each adjuvant's effects on AMP, AUC, and latency to 100% peak AMP were evaluated with and without bupivacaine, then statistically compared with control (no drug) and bupivacaine-alone conditions.

Results: EC50s for the four adjuvants were determined for some fibers: dexmedetomidine (A-alpha/beta, A-delta, C fibers), magnesium (A-delta fibers), epinephrine (C fibers), and ketorolac (A-alpha/beta and A-delta fibers). At the high concentrations, adjuvants alone produced few significant differences when compared with control, and adjuvants with bupivacaine produced few significant differences when compared with bupivacaine alone.

Discussion: Using ex vivo electrophysiology, we identified EC50s of dexmedetomidine, magnesium, epinephrine, and ketorolac for A-alpha/beta, A-delta, and/or C fiber AMP, demonstrating that these adjuvants have direct effects on PN fibers. Future investigations may benefit by testing different concentrations of adjuvants and bupivacaine in an in vivo model incorporating a broader range of time points.