Regional Anesthesia and Pain Medicine最新文献

Background and objectives: Chronic knee pain, including postarthroplasty knee pain, is a major cause of morbidity. Radiofrequency ablation of genicular nerve branches is a treatment option. The literature to date has demonstrated and recommended consistent rhizotomy targets in the coronal and axial position of the three primary genicular nerve branches (superomedial genicular nerve, superolateral genicular nerve, inferomedial genicular nerve). The debate on genicular nerve positions focuses on the anterior-posterior courses of the nerve branches.

Methods: The sagittal positions of the three primary genicular neurovascular bundles were measured in 28 consecutive knee MRI and described relative to the total anterior-posterior depth of the bony cortex. Standard radiofrequency capture radius at the classic rhizotomy targets sites was compared with identified nerve position to report proportion of observed nerves within the capture radius.

Results: The genicular neurovascular bundles were found further posterior than classic landmark targets. Proportion of visualized nerve branches captured by classic rhizotomy target radius varied by genicular nerve branch.

Conclusions: This study supports updated guidance on genicular rhizotomy targets. Nerve localization studies using MRI data may be a promising avenue in future nerve localization research pertinent to rhizotomy.

Background: Different approaches to the obturator nerve have been described. However, few have focused on the injection point inferior the iliopubic ramus, specifically at the exit of the obturator canal. This study aims to anatomically evaluate the ultrasound-guided obturator nerve block at the exit of the obturator canal, detailing anatomical landmarks and solution distribution.

Methods: This anatomical study was conducted using 10 cadavers to generate 20 hemipelvis samples. Ultrasound references were utilized to identify the obturator canal, iliopubic ramus, pectineus and external obturator muscles, and the obturator membrane. An ultrasound-guided obturator nerve block was performed using a low-frequency convex probe for initial identification and a high-frequency linear transducer for the injection of a methylene blue solution. Subsequent dissections were performed to evaluate the distribution of the dye within the obturator nerve.

Results: The injection of methylene blue consistently stained the common trunk and anterior branch of the obturator nerve in 100% of the cases and the posterior branch in 80% of the samples. Intrapelvic staining was observed in 65% of the specimens, indicating effective diffusion of the dye. Key anatomical landmarks, such as the iliopubic ramus and the obturator membrane, were crucial for accurate identification and injection.

Conclusion: In conclusion, sagittal approaches using the iliopubic ramus as an anatomical reference achieve the most complete obturator nerve block. Our anatomical study details the structures of the obturator canal and access to the obturator nerve at its exit. Future studies are needed to confirm its safety and efficacy.

Background: While many medical specialties have established links between bibliometric indices, academic rank, leadership roles, and National Institutes of Health (NIH) funding, there exists a gap within the field of pain medicine. The purpose of our study is to examine the impact of research productivity (h-index, m-index, publications, citations), professional degrees (PhD, MPH, MBA), leadership positions (program director, division chief, chairman), and faculty demographics (gender, nationality of training) on attaining NIH grant funding among pain medicine faculty.

Methods: A complete list of 98 civilian pain medicine programs was included in the study. Between September 1, 2022, and December 30, 2022, departmental websites were accessed to accrue a list of pain medicine faculty listings. Publicly available information was used to extract research productivities, professional degrees, leadership positions, faculty demographics, and NIH grant funding. Descriptive statistics were used for analysis, with NIH funding status as the primary outcome.

Results: A total of 696 pain physicians within the academic community were identified. Markers of research productivity such as a higher h- or m-index, larger number of publications and citations, PhD status, and being senior faculty (full professor, division chief, or chairman) were independently associated with NIH funding. There was no statistical difference (p>0.05) among males and females in the number of R grants received.

Conclusions: We have identified many factors associated with NIH funding status and failed to find significant gender disparities in NIH funding. These findings allow for chronic pain programs to have another set of tools to attract, promote, and retain faculty.

Background/importance: Local anesthetic (LA) mixtures are used in peripheral nerve blocks (PNB) to improve onset, though study results remain conflicting.

Objective: This systematic review and meta-analysis compared the efficacy outcomes of long-acting LA to their mixture with shorter-acting LA in ultrasound-guided PNB. The primary outcome was sensory block onset.

Evidence review: We searched WoS, Scopus, MEDLINE, EMBASE, BVS/LILACS, and Cochrane databases from 1998 to 2024 for randomized controlled trials (RCTs). We conducted a random-effects meta-analysis, evaluated the risk of bias (RoB) with RoB 2.0, performed sensitivity analyses, assessed non-reporting bias with DOI plots and Luis Furuya-Kanamori index, and evaluated strength of evidence with Grading of Recommendations Assessment, Development and Evaluations.

Findings: We included 10 RCTs (516 participants). Mixture of LA may have no effect on sensory block onset (mean difference (MD) -1.62 min, 95% CI: -4.04 to 0.81; I²=81.50%, 95% CI: 62.82% to 90.80%; prediction interval (PI)=-7.78 to 4.55; very low certainty) and motor block onset (MD -5.60 min; 95% CI: -14.54 to 3.33, I²=98.89%, 95% CI: 98.50% to 99.18%; PI=-31.90 to 20.69; very low certainty), while it may reduce the duration of sensory block (MD -2.16 hours, 95% CI: -4.16 to -0.17; I²=90.77%, 95% CI: 84.22% to 94.60%; PI=-7.24 to 2.92; very low certainty).

Conclusions: LA mixtures may not affect sensory and motor block onset in ultrasound-guided PNB but could shorten the duration of sensory blockade.

Background: The perioperative use of methadone is increasing because of its favorable effects on postoperative analgesia and opioid consumption. Methadone can cause QTc interval prolongation, increasing the risk of Torsades de Pointes. The effect of an intraoperative loading dose of methadone on intraoperative QTc interval prolongation is unknown.

Methods: A retrospective observational cohort study of patients aged ≥18 years who underwent major non-cardiopulmonary surgery was conducted. Patients receiving an intraoperative loading dose of methadone were assigned to the methadone group; others formed the non-methadone group. Single-lead ECGs (II) were analyzed using a wavelet-based QTc interval algorithm to obtain 1- min average QTc interval values at baseline and intraoperatively. The outcome measure was the occurrence of any intraoperative 1- min averaged time windows that exceeded the predefined thresholds of 500 ms (primary), increase of ≥30 ms from baseline and increase of ≥60 ms from baseline (secondary). Propensity score matching was performed.

Results: A total of 637 patients were included, and after propensity score matching (1:1 ratio), 244 patients were analyzed. A QTc interval >500 ms (23.8% vs 23.0%; p=0.88), an increase of ≥30 ms from baseline (67.8% vs 75.0%; p=0.22), and an increase of ≥60 ms from baseline (29.7% vs 22.4%; p=0.21) occurred equally in the non-methadone group compared with the methadone group. The percentage of intraoperative time spent above threshold was significantly higher in the non-methadone group for the>500 ms threshold (p=0.004).

Conclusion: The implementation of methadone for perioperative pain management was not associated with an increased incidence of intraoperative QTc interval prolongation.

Background: Substance use among surgical patients is common and correlated with greater postoperative opioid use. However, the association of preoperative substance use on postoperative pain is unknown. In this context, a brief, validated tool such as the Tobacco, Alcohol, Prescription medication, and other Substance use (TAPS) Questionnaire could provide valuable information to assess the risk of poor postoperative pain control.

Methods: We prospectively identified adults aged 18 years and older undergoing common surgical procedures between December 2018 and July 2023 across three institutions. Patients completed the TAPS measure prior to surgery. A positive TAPS screen was defined as tobacco use ≥monthly, heavy alcohol use ≥monthly, any use of recreational drugs, or any use of prescription medication not as prescribed. The primary outcome was 'worst' overall pain (on a scale of 0-10, 0=no pain, 10=worst pain imaginable) at three time points: prior to surgery, 2 weeks postoperatively, and 1 month postoperatively. Mixed linear models were used to determine the association between TAPS Score and pain over time, adjusting for patient factors.

Results: In this cohort of 4410 individuals, 42.2% reported unhealthy substance use using TAPS in the 12 months prior to surgery. After adjusting for patient factors, participants who screened positively on TAPS reported higher worst overall pain scores than those with negative TAPS screens at baseline (3.51 vs 3.15, p<0.001) and at 1 month postoperatively (2.66 vs 2.41, p=0.036). No significant difference was observed at 2 weeks after surgery.

Conclusions: Preoperative substance use is common and is correlated with higher levels of patient-reported pain after surgery, but within minimal clinically important differences. These findings are preliminary and require confirmation. Risky substance use has an important impact on postoperative recovery, and the perioperative window provides an opportunity to assess and intervene in unhealthy substance use.

Introduction: Vagus Associated Neurogenic Cough Occurring due to Unilateral Vascular Encroachment of its Root (VANCOUVER) syndrome is a recently described neurovascular compression syndrome causing neurogenic cough due to a vascular compression of the vagus nerve at the brainstem. Some patients with VANCOUVER syndrome can lateralize the tickling sensation causing their irresistible cough; others cannot. For those who cannot lateralize their symptoms, a diagnostic vagus nerve block is required. This paper highlights the technique of percutaneous cervical vagus nerve block and its use in the diagnostic protocol for VANCOUVER syndrome.

Methods: The medical records of two patients who underwent a vagus nerve block were reviewed. The percutaneous cervical vagus nerve block was performed in the supine position, under ultrasound guidance with an in-plane needle technique as an outpatient procedure. Hemodynamic parameters and clinical effects were monitored.

Results: Both patients were identified as potentially having VANCOUVER syndrome but could not lateralize their sensory symptoms. Each underwent unilateral vagus nerve block and returned for the contralateral procedure several weeks later. Both had temporary resolution of their cough following vagus nerve block ipsilateral to the intracranial vagus nerve compression but no effect following contralateral vagus nerve block. During the effects of the vagus nerve block, the patients had temporary vocal hoarseness, ipsilateral Horner syndrome, but no hemodynamic disturbances.

Conclusion: Vagus nerve block can confirm the diagnosis and lateralize the affected nerve in patients with VANCOUVER syndrome who cannot lateralize their symptoms. As the awareness of this syndrome increases, the procedure will become more common. An understanding of ultrasound-guided cervical anatomy is required for its safe use.

Background: Contrast epidurography is an objective and reliable imaging modality to confirm the appropriate placement of thoracic epidural catheters for postoperative analgesia. To date, no large studies have reported failure rates of catheter placement as confirmed by contrast epidurography, nor have they associated patient and procedural factors.

Methods: This was a single-center retrospective study analyzing failure rates and associated patient and procedural factors for thoracic epidural catheters placed using a conventional landmark-based technique and confirmed by contrast epidurography. All epidural contrast studies taken over a 5-year study period were analyzed along with potential predictors of failure, including patient age, sex, body mass index, a diagnosis of thoracic scoliosis, patient positioning, needle approach, training level of primary operator, and fellowship training of the supervising anesthesiologist.

Results: 1017 epidural contrast studies were included for analysis. The failure rate after initial catheter placement was 12.2%. For catheters placed as a second attempt to "rescue" a failed initial attempt, the failure rate was 24.0%. Multivariable logistic regression analysis showed a greater odds of failed placement associated with obesity compared with regular weight (adjusted OR (aOR): 1.9, 95% CI 1.12 to 3.3) and older age compared with age <55 (aOR for age 55-74: 2.78, 95% CI 1.39 to 6.21; aOR for age ≥75: 4.16, 95% CI 1.94 to 9.77).

Conclusions: Failure rates for thoracic epidural catheter placement as confirmed by contrast epidurography at a teaching institution are reported. Age≥55 and obesity are both associated with a greater odds of failed placement.