Regional Anesthesia and Pain Medicine最新文献

Introduction: Patients hospitalized for headache treatment pose unique challenges to the healthcare system. Currently, there is a lack of evidence-based guidance on management. This practice advisory aims to fill this critical gap by systematically reviewing the existing literature and providing comprehensive, evidence-based recommendations for managing headache patients during hospitalization.

Methods: In February 2023, the American Society of Regional Anesthesia and Pain Medicine approved this practice advisory proposal. The steering committee selected committee members based on clinical and research expertise in the field of headache medicine. Nine questions were formulated by the committee, and each question was assigned to a group composed of 3-4 members. A systematic literature search for each question was performed in Medline, Embase, Cochrane Database of Systematic Reviews and Web of Science on June 21, 2023. The results from each search were imported into separate Covidence projects for screening, data extraction, and risk of bias assessment. Additionally, relevant systematic reviews (SR) were screened. Each group submitted a structured narrative review along with statements and recommendations based on the US Preventive Services Task Force (USPSTF) format for grading of evidence. While the USPSTF framework was used, including the language in the recommendations, the formal USPSTF methodology, including the SR with meta-analysis and summary tables with forest plots, was not followed because of low overall evidence quality. The interim draft was shared electronically with each collaborator, who was requested to vote anonymously using two rounds of the modified Delphi approach. A consensus recommendation required >75% agreement.

Results: The panel generated 12 statements and 17 recommendations, along with their strength and certainty of evidence. Following two rounds of Delphi voting, a high consensus was achieved for all statements and recommendations. Most statements received a low-to-moderate level of certainty, and all but one recommendation received grade B or C, which was consistent with the lack of randomized controlled trials supporting most of the drugs in this document.

Conclusions: This evidence-based practice advisory provides a foundational step toward standardizing inpatient headache care and highlights existing gaps in the literature that should be addressed through rigorous prospective randomized studies.

Background: Clinical studies suggest that long-term conventional spinal cord stimulation (LT-SCS) for painful diabetic peripheral neuropathy (PDPN) is initially effective but may decline in efficacy over time. Preclinical studies indicate that LT-SCS alleviates mechanical hypersensitivity and enhances hind paw blood flow in PDPN rats, suggesting nociceptive system plasticity. This study hypothesized that LT-SCS induces peripheral hind paw small-fiber sprouting and reduces central protein expression of glial and P2X4 brain-derived neurotrophic factor (BDNF) pathway markers.

Methods: Diabetes was induced via Streptozotocin injection in 32 rats, with 16 developing PDPN and receiving a quadrupolar lead implant. LT-SCS was applied for 4 weeks, 12 hours per day. Pain behavior was assessed using the Von Frey test for mechanical hypersensitivity and the mechanical conflict avoidance system for motivational aspects of pain. Fiber sprouting was assessed via immunohistochemical analysis of nerve fibers in the hind paw skin. Protein expression in the spinal cord was assessed using western blotting.

Results: LT-SCS increased the baseline threshold of mechanical hypersensitivity in PDPN animals, consistent with previous findings, but showed no effects on motivational aspects of pain. Hind paw tissue analysis revealed significantly increased intraepidermal nerve fiber density of PGP9.5 fibers in LT-SCS animals compared with Sham-SCS animals. Protein analysis showed significantly decreased pro-BDNF expression in LT-SCS animals compared with Sham-SCS animals.

Conclusion: LT-SCS induces structural changes in both peripheral and central components of the nociceptive system in PDPN animals. These changes may contribute to observed behavioral modifications, elucidating mechanisms underlying LT-SCS efficacy in PDPN management.

Background: There is scarce literature regarding the use of continuous peripheral nerve blocks in acute burn patients, who may be at higher risk for catheter-related complications, including infection. We sought to describe our center's experience and infection rate with continuous perineural catheters in the setting of pain management for patients suffering from burns.

Methods: A retrospective observational study was performed including all patients admitted to an American Burn Association-verified regional burn center between January 2018 and July 2023 who received a continuous peripheral nerve block for an acute burn injury.

Results: There were 281 patients in the study cohort who received 484 perineural catheters. The cohort was 52% men with a median age of 39 years (IQR 30-55). A catheter-associated infection, defined as a clinical diagnosis by the treating physicians requiring the need for treatment with antibiotics or surgical debridement, was identified in six perineural catheters (1.2%, 95% CI 0% to 2.2%) involving six different patients (2.1%, 95% CI 0% to 3.8%). The median total body surface area burned was 5% (IQR 2-9%) and 20% of patients had full-thickness burns. The most commonly used catheters were infraclavicular (49%), popliteal sciatic (29%), femoral (19%), and adductor canal (17%). One-third (33%) of patients did not require operating room debridement as the block provided sufficient analgesia for bedside debridement. The median duration of catheter use was 6 days (IQR 4-8). There were no documented cases of nerve injury or toxicity, vascular injury, or local anesthetic systemic toxicity.

Conclusions: In our practice, continuous perineural catheters in the setting of acute burns are associated with an infection rate comparable to other surgical populations.

Introduction: Postoperative pain after laparoscopic abdominal surgery remains complex. While lateral quadratus lumborum (QL) block and transversus abdominus plane (TAP) block are similar techniques, no studies have examined if one technique has greater dermatomal spread.

Methods: Laparoscopic colorectal surgical patients were randomized to lateral QL or TAP blocks. Dermatomal anesthetic spread, as measured by loss of sensation to temperature in the postanesthesia care unit, was the primary outcome. If a clear level of dermatomal anesthesia could not be defined, the block was categorized as "indeterminate." Secondary outcomes included opioid consumption, pain scores, and opioid-related side effects.

Results: 153 patients completed the study (75 QL and 78 TAP). Mean (95% CI) number of dermatomes with loss of sensation to ice was greater in subjects randomized to QL (4.2 (3.7 to 4.8)) versus TAP (2.7 (2.2 to 3.2); p=0.0001), and the QL group was more likely to have loss of sensation above T8 (p=0.01) and T10 (p=0.02). Indeterminate block was more often noted with TAP blocks (p<0.0001). Opioid consumption at 24 hours, pain scores, and opioid-related side effects did not differ.

Discussion: Compared with TAP blocks, QL blocks had greater dermatomal anesthesia spread and lower rates of an indeterminate block. However, differences in pain and opioid consumption were not noted. The clinical importance of these findings should be investigated in future trials.

Trial registration number: NCT03490357.

Background: Many patients with brachial plexus avulsion (BPA) suffer from neuropathic pain, but the mechanism remains elusive. Modifications of histones, the proteins responsible for organizing DNA, may play an important role in neuropathic pain. Lysine demethylase 4A (KDM4A), an essential component of histone demethylase, can modify the function of chromatin and thus regulate the vital gene expressions. However, the mechanism by which KDM4A regulates neuropathic pain following BPA remains unclear.

Methods: The pain model was developed in adult rats that received BPA surgery. Western blot, ELISA, and reverse transcription-PCR were used to examine the protein and mRNA levels of targeted genes. Immunofluorescence studies were conducted to analyze their cellular distribution in the spinal cord. Pharmacological and genetic methods were used to modulate the expression of KDM4A. Co-immunoprecipitation and chromatin immunoprecipitation PCR were used to assess the binding potential between KDM4A and the promoter of brain-derived neurotrophic factor (BDNF).

Results: KDM4A and BDNF levels were significantly upregulated in the ipsilateral spinal cord dorsal horn in the BPA group compared with the sham surgery group. Additionally, knockdown of KDM4A decreased BDNF expression and microgliosis and reduced neuropathic pain-like behaviors in BPA rats. Conversely, KDM4A overexpression increased BDNF expression and microgliosis and exacerbated neuropathic pain. BDNF inhibitors and activators also regulated the activation of spinal microglia and neuropathic pain. Importantly, we showed that KDM4A modulates BDNF expression by regulating the methylation of histone 3 lysine 9 and histone 3 lysine 36 in its promoter region.

Conclusion: Current findings suggest that the upregulation of KDM4A increases BDNF expression in the spinal cord in rats after BPA, contributing to microgliosis, neuroinflammation, and neuropathic pain.

Innervation of the shoulder joint is complex and remains poorly understood among regional anesthesiologists and chronic pain specialists. Current literature supports the important contribution of the axillary nerve to the total innervation of the shoulder, as well as its blockade for perioperative pain and denervation for chronic shoulder pain. However, a description of the entire course of the axillary nerve, the corresponding optimal targets, and the sonoanatomy pertinent to pain intervention is lacking. This educational article discusses in detail the functional anatomy and sonographic identification of possible windows for axillary nerve intervention. We discuss the contribution, extent, and type of innervation the axillary nerve provides to the shoulder joint, which is often misunderstood. Ultimately, this article serves to stimulate thoughts and ideas for future research in an area where literature is scarce.

Background: While superficial parasternal intercostal plane blocks can improve analgesia after cardiac surgery, the optimal site and the number of injections remain uncertain. This study aimed to compare the efficacy of single versus double injections of superficial parasternal blocks, hypothesizing that double injections would achieve superior cutaneous sensory blockade.

Methods: 70 cardiac patients undergoing median sternotomy were randomly assigned to receive either single or double injections of superficial parasternal blocks bilaterally. Each patient received 40 mL of 0.25% bupivacaine with epinephrine 5 µg/mL and dexamethasone 10 mg. The single-injection group received 20 mL/side at the third costal cartilage, while the double-injection group received 10 mL/injection at the second and fourth costal cartilages. The primary outcome was a successful block, defined as sensory loss in the T2-T6 dermatomes. Secondary outcomes included sensory block of T1, T7, and T8 dermatomes, block-related complications, intraoperative hemodynamics, postoperative pain intensity, opioid consumption, and recovery quality.

Results: Double injections achieved an overall higher success rate compared with the single-injection technique (81% vs 51%, relative risk 1.6; 95% CI 1.2, 2.0; p<0.001). Additionally, higher blockade percentages were observed in dermatomes T1 (83% vs 59%, p=0.003), T7 (67% vs 46%, p=0.017), and T8 (61% vs 39%, p=0.011) with double injections. Other secondary outcomes did not differ significantly between groups.

Conclusions: Compared with single injection, double injections of superficial parasternal blocks provided more reliable coverage of the T2-T6 dermatomes, crucial for median sternotomy. However, no differences were observed in intraoperative hemodynamic effects or postoperative pain control after cardiac surgery.

Trial registration number: TCTR20230408004.

Background and aims: Minimally invasive repair of pectus excavatum is associated with intense postoperative pain. We aimed to evaluate the effectiveness of percutaneous intercostal cryoanalgesia according to the different timing of its preoperative application. Outcome variables included pain, drug consumption, time to mobilization, and hospital length of stay.

Methods: Retrospective data analyzed from a single pediatric institution, involving a series of consecutive patients who underwent pectus surgery. Group 1: 18 patients received thoracic epidural analgesia. Group 2: 11 patients underwent cryoanalgesia on the same day of surgery and epidural analgesia as a bridge to cryoanalgesia onset. Group 3: 13 patients underwent earlier preoperative intercostal cryoanalgesia with a median of 6 days (IQR 3-6) before surgery. All groups received rescue systemic analgesia.

Results: Pain scores were similar among groups. The incidence of severe pain decreased in Group 3 versus Group 1 (38% vs 78%) (p<0.05). Ropivacaine epidural cumulative dose (mg/kg) decreased in Group 2 versus Group 1: 16 (IQR 12-23) versus 27 (IQR 22-35) (p<0.01). Cumulative oral morphine equivalent dose (mg/kg) decreased among groups: 12 (IQR 9.3-17), 8 (IQR 4.2-12), and 0.2 (IQR 0.0-0.3) (p<0.001) for Groups 1-3, respectively. Length of stay (days) also decreased among Groups 1-3, respectively: 7 (IQR 6-7), 6 (IQR 5-7), and 4 (IQR 4-5) (p<0.001).

Conclusions: This exploratory observational study suggests that the timing of cryoanalgesia may play a crucial role in its efficacy, with earlier placement being associated with improvements in pain, opioid utilization, and length of stay.