Outcomes of Regional Block in Revision Total Joint Arthroplasty for Prosthetic Joint Infection

INTRODUCTION

Infection is among the most common reasons for revision after a total joint arthroplasty (TJA) and is associated with notable morbidity and mortality rates. As the demand for TJA increases, a concurrent increase in the prevalence of periprosthetic joint infection (PJI) is also expected to rise. While previous studies have explored differences in postoperative outcomes between general and spinal anesthesia, there is limited data on the use of regional blocks in patients undergoing revision joint arthroplasty for PJI. This study evaluated the postoperative outcomes of patients undergoing revision TJA for PJI using regional blocks.

METHODS

Data from 518 patients were retrospectively collected. Patients included in the study had undergone revision TJA for PJI from January 2004 to January 2023 at a single institution. Patients undergoing same-day bilateral revisions, above-knee amputations, and aseptic revisions were excluded. Postoperative complications investigated included local complications, postoperative transfusion, wound complication, readmission, sepsis, systemic infection, spinal infection, death, persistent PJI, periprosthetic fracture, and unplanned revision surgery. Chi-square analysis was used to compare postoperative complications between procedures that used spinal or general anesthesia with regional blocks and those with spinal or general anesthesia without regional blocks.

RESULTS

Of the 518 patients who underwent revision TJA, 63 (12.2%) used a regional block. After surgery, 12.7% (n = 8) of patients with regional block and 23.5% (n = 107) of patients without regional block experienced persistent PJI (P = 0.076). No significant differences in wound complication (P = 0.333), readmission (P = 0.998), revision surgery (P = 0.783), and death (P = 0.588) were found between those with and without regional block use. Sepsis (P = 0.224), systemic infection (P = 0.220), and spinal infection (P = 0.998) rates within 1 year after revision TJA for PJI surgery were comparable between the two groups. No local infections were observed at the block site. A subanalysis comparing spinal and general anesthesia demonstrated comparable persistent PJI postoperatively and complication rates; however, spinal anesthesia use was associated with shorter length of stay (P = 0.003) and lower transfusion rates (P = 0.002).

CONCLUSION

The results of this study suggest that the use of regional block is not associated with an increased probability of postoperative persistent PJI, local wound complication, readmission, spinal/systemic/other infections, death, or revision surgery. Surgeons can comfortably choose regional block as a safe option for revision surgery for PJI. Consistent with previous research, patients who received spinal anesthesia had shorter hospital stays and lower transfusion rates when compared with those who received general anesthesia.

Regional anesthesia is safe for use in intramedullary nailing of low-energy tibial shaft fractures

PURPOSE

The purpose was to compare perioperative outcomes of patients who underwent general or regional anesthesia for intramedullary (IM) nailing of tibial shaft fractures (TSFs).

METHODS

Retrospective chart review was performed on a consecutive series of low-energy TSF patients who presented to a single academic medical center and a level 1 trauma center who underwent operative repair with a reamed IM nail. Collected information included demographics, injury information, anesthesia type (general or regional i.e. peripheral nerve block), intra-operative opiate consumption (converted to morphine milliequivalents [MME], and post-operative pain visual-analog scale [VAS] pain scores. Patients were divided into 3 groups based on the type of anesthesia received and univariate analysis was performed to compare the 3 groups.

RESULTS

Seventy-six patients were included, with an average age of 44.47±16.0 years. There were 38 (50 %) who were administered general anesthesia and 38 (50 %) who were administered regional anesthesia in the form of a peripheral nerve block. There were no differences between the groups with respect to demographics, medical co-morbidities, rate of open fractures or AO/OTA fracture classification. Regional anesthesia patients received less intra-operative MME than general anesthesia patients (17.57±10.6, 28.96±13.8, p < 0.001). Patients who received regional anesthesia also spent less time in the operating room, received less MME on post-operative day 1, and ambulated further on post-operative day 1, however none of these differences were statistically significant. There were no cases of missed post-operative compartment syndrome or complications related to the administration of the peripheral nerve block.

CONCLUSIONS

Regional anesthesia in TSF surgery received less intra-operative opioid requirements, without any untoward effects.

LEVEL OF EVIDENCE

Therapeutic Level III.

Association of anesthetic modality and other variables on 1-year functional patency of cephalic-based arteriovenous fistulae

OBJECTIVE

Some studies suggest that regional anesthesia provides better patency for arteriovenous fistula (AVF) for hemodialysis access as compared to local and general anesthesia. This study evaluates the impact of anesthetic modality on long term fistula function at 12 months.

METHODS

A retrospective review of patients undergoing cephalic vein-based hemodialysis access in consecutive cases between 2014 and 2019 was conducted from five safety net hospitals. The primary endpoint was functional patency at 12 months. Subset analysis individually evaluated cephalic-based lower forearm and wrist vs upper arm AVFs. Bivariate and multivariate logistic regression models evaluated the relationship between anesthetic modality and fistula function at 12 months.

RESULTS

There were 818 cephalic-based fistulas created during the study period. The overall 12-month functional patency rate was 78.7%, including an 81.3% patency for upper arm AVF and 73.3% for wrist AVF (P = .009). There was no statistically significant difference among patients with functional and nonfunctional AVFs at 12 months with respect to anesthetic modality when comparing regional, local, and general anesthesia (P = .343). Multivariate regression analysis identified that history of AVF/arteriovenous graft (odds ratio [OR], 0.24; P = .007), receiving intraoperative systemic anticoagulation (OR, 2.49; P < .001), and vein diameter (OR, 1.85; P = .039) as independently associated with AVF functional patency at 12 months.

CONCLUSIONS

There was no association between anesthetic modality and functional patency of cephalic-based AVFs at 12 months. Further studies are needed to better define which patients may benefit from regional anesthesia.

Comparison of regional vs. general anesthesia on the risk of dementia: a systematic review and meta-analysis

Background

Dementia is a gradual and ongoing cognitive decline due to damage to nerve cells in the brain. This meta-analysis aimed to assess the potential relationship between regional anesthesia (RA) and the risk of dementia.

Methods

Electronic databases including Embase, Medline, Google Scholar, and Cochrane Library were searched for studies investigating the association between RA and dementia risk from inception to March 2022. The primary outcome was the risk of dementia in patients who underwent RA (RA group) and those who received general anesthesia (GA group). Secondary outcomes included identifying other potential risk factors for dementia and comparing dementia risk between individuals receiving RA and those not receiving surgery/anesthesia (placebo group).

Results

Eight cohort studies published between 2014 and 2023 were included in this analysis. A meta-analysis of the available data demonstrated no differences in baseline characteristics and morbidities (i.e., age, male proportion, hypertension, diabetes, depression, and severe comorbidities) between the RA and GA groups (all p > 0.05). Initial analysis revealed that the risk of dementia was higher in the GA group than in the RA group (HR = 1.81, 95% CI = 1.29-2.55, p = 0.007, I 2 = 99%, five studies). However, when a study featuring a relatively younger population was excluded from the sensitivity analysis, the results showed a similar risk of dementia (HR, 1.17; p = 0.13) between the GA and RA groups. The pooled results revealed no difference in dementia risk between the RA and placebo groups (HR = 1.2, 95% CI = 0.69-2.07, p = 0.52, I 2 = 68%, three studies). Sensitivity analysis revealed that the evidence was not stable, suggesting that limited datasets precluded strong conclusions on this outcome. Anxiety, stroke history, hypertension, diabetes, hyperlipidemia, and diabetes are potential predictors of dementia.

Conclusion

Our results emphasize that, while RA could be protective against dementia risk compared to GA, the association between the type of anesthesia and dementia risk might vary among different age groups. Owing to the significant prevalence of dementia among older people and their surgical needs, further investigations are warranted to clarify the association between dementia risk and regional anesthesia.Systematic review registration: https://www.crd.york.ac.uk/prospero/, CRD42023411324.

Racial and ethnic disparities in regional anesthesia in the United States: A narrative review

BACKGROUND

Racial and ethnic disparities exist in the delivery of regional anesthesia in the United States. Anesthesiologists have ethical and economic obligations to address existing disparities in regional anesthesia care.

OBJECTIVES

Current evidence of racial and ethnic disparities in regional anesthesia utilization in adult patients in the United States is presented. Potential contributors and solutions to racial disparities are also discussed.

EVIDENCE REVIEW

Literature search was performed for studies examining racial and ethnic disparities in utilization of regional anesthesia, including neuraxial anesthesia and/or peripheral nerve blocks.

FINDINGS

While minoritized patients are generally less likely to receive regional anesthesia than white patients, the pattern of disparities for different racial/ethnic groups and for types of regional anesthetics can be complex and varied. Contributors to racial/ethnic disparities in regional anesthesia span hospital, provider, and patient-level factors. Potential solutions include standardization of regional anesthetic practices via Enhanced Recovery After Surgery (ERAS) pathways, increasing patient education, health literacy, language translation services, and improving diversity and cultural competency in the anesthesiology workforce.

CONCLUSION

Racial and ethnic disparities in regional anesthesia exist. Contributors and solutions to these disparities are multifaceted. Much work remains within the subspecialty of regional anesthesia to identify and address such disparities.

Efficacy and safety of ketamine as an adjuvant to regional anesthesia: A systematic review and meta-analysis of randomized controlled trials

STUDY OBJECTIVE

To identify whether adding ketamine to the local anesthetics (LA) in the regional anesthesia could prolong the duration of analgesia.

DESIGN

A Systematic review and meta-analysis of randomized controlled trials.

SETTING

The major dates were obtained in the operating room and the postoperative recovery ward.

PATIENTS

A total of 1011 patients at ASA physical status I and II were included in the analysis. Procedure performed including cesarean section, orthopedic, radical mastectomy, urological or lower abdominal surgery and intracavitary brachytherapy implants insertion.

INTERVENTIONS

After an extensive search of the electronic database, patients received regional anesthesia combined or not combined general anesthesia and with or without adding ketamine to LA were included in the analysis. The regional anesthesia includes spinal anesthesia, brachial plexus block, pectoral nerve block, transversus abdominis plane block and femoral and sciatic nerve block.

MEASUREMENT

The primary outcome was the duration of analgesia. Secondary outcomes were the duration and onset time of motor and sensory block as well as the ketamine-related adverse effect. Data are expressed in mean differences in continuous data and odds ratios (OR) for dichotomous data with 95% confidence intervals. The risk of bias of the included studies was evaluated using the revised Cochrane risk of bias tool for randomized trials. The quality of evidence for each outcome was rated according to the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) Working Group system.

MAIN RESULT

Twenty randomized controlled trials were included in the analysis. When ketamine was used as an adjuvant to LA, the duration of analgesia could be prolonged(172.21 min, 95% CI, 118.20 to 226.22; P<0.00001, I2 = 98%), especially in the peripheral nerve block(366.96 min, 95% CI, 154.19 to 579.74; P = 0.0007, I2 = 98%). Secondary outcomes showed ketamine could prolong the duration of sensory block(29.12 min, 95% CI, 10.22 to 48.01; P = 0.003, I2 = 96%) but no effect on the motor block(6.94 min, 95% CI,-2.65 to 16.53;P = 0.16, I2 = 84%), the onset time of motor and sensory block (motor onset time, -1.17 min, 95% CI, -2.67 to 0.34; P = 0.13, I2 = 100%; sensory onset time, -0.33 min, 95% CI,-0.87 to 0.20; P = 0.23, I2 = 96%) as well as the ketamine-related adverse effect(OR, 1.97, 95% CI,0.93 to 4.17;P = 0.08, I2 = 57%).

CONCLUSION

This study indicates that ketamine could be an ideal adjuvant to local anesthetics regardless of the types of anesthesia. Overall, the quality of the evidence is low.

Leading in the development, standardised evaluation, and adoption of artificial intelligence in clinical practice: regional anaesthesia as an example

A recent study by Suissa and colleagues explored the clinical relevance of a medical image segmentation metric (Dice metric) commonly used in the field of artificial intelligence (AI). They showed that pixel-wise agreement for physician identification of structures on ultrasound images is variable, and a relatively low Dice metric (0.34) correlated to a substantial agreement on subjective clinical assessment. We highlight the need to bring structure and clinical perspective to the evaluation of medical AI, which clinicians are best placed to direct.

Regional anaesthesia education for consultants and specialists in the UK: a mixed-methods analysis

BACKGROUND

Regional anaesthesia plays an important role in perioperative care, but gaps in proficiency persist among consultants and specialists. This study aimed to assess confidence levels in performing Plan A blocks among this cohort and to examine the barriers and facilitators influencing regional anaesthesia education.

METHODS

Utilising a mixed-methods design, we performed a quantitative survey to gauge self-reported confidence in performing Plan A blocks, coupled with qualitative interviews to explore the complexities of educational barriers and facilitators. UK consultant and specialist anaesthetists were included in the study.

RESULTS

A total of 369 survey responses were analysed. Only 22% of survey respondents expressed confidence in performing all Plan A blocks. Specialists (odds ratio [OR] 0.391, 95% confidence interval [CI] 0.179-0.855, P=0.016) and those in their roles for >10 yr (OR 0.551, 95% CI 0.327-0.927, P = 0.024) reported lower confidence levels. A purposive sample was selected for interviews, and data saturation was reached at 31 interviews. Peer-led learning emerged as the most effective learning modality for consultants and specialists. Barriers to regional anaesthesia education included apprehensions regarding complications, self-perceived incompetence, lack of continuing professional development time, insufficient support from the multidisciplinary team, and a lack of inclusivity within the regional anaesthesia community. Organisational culture had a substantial impact, with the presence of local regional anaesthesia champions emerging as a key facilitator.

CONCLUSIONS

This study highlights persistent perceived deficiencies in regional anaesthesia skills among consultants and specialists. We identified multiple barriers and facilitators, providing insights for targeted interventions aimed at improving regional anaesthesia education in this group.

Celebrating the state of the art and innovations in regional anaesthesia in the British Journal of Anaesthesia

To coincide with the annual scientific meeting of Regional Anaesthesia UK in London 2024, where there is a joint scientific session with the British Journal of Anaesthesia, a special regional anaesthesia edition of the journal has been produced. This editorial offers some highlights from the manuscripts contained within the special edition.

Examining disparities in regional anaesthesia and pain medicine

In high-resource countries, health disparities exist in both treatment approaches and health outcomes. Race and ethnicity can serve as proxies for other socioeconomic factors and social determinants of health such as income, education, social support, and residential neighbourhood, which strongly influence health outcomes and disparities. In regional anaesthesia and pain medicine, disparities exist across several surgical specialties including obstetrics, paediatrics, and orthopaedic surgery. Understanding these disparities will facilitate development of solutions aimed at eliminating disparities at the patient, physician/provider, and healthcare system levels.

Research priorities in regional anaesthesia: an international Delphi study

BACKGROUND

Regional anaesthesia use is growing worldwide, and there is an increasing emphasis on research in regional anaesthesia to improve patient outcomes. However, priorities for future study remain unclear. We therefore conducted an international research prioritisation exercise, setting the agenda for future investigators and funding bodies.

METHODS

We invited members of specialist regional anaesthesia societies from six continents to propose research questions that they felt were unanswered. These were consolidated into representative indicative questions, and a literature review was undertaken to determine if any indicative questions were already answered by published work. Unanswered indicative questions entered a three-round modified Delphi process, whereby 29 experts in regional anaesthesia (representing all participating specialist societies) rated each indicative question for inclusion on a final high priority shortlist. If ≥75% of participants rated an indicative question as 'definitely' include in any round, it was accepted. Indicative questions rated as 'definitely' or 'probably' by <50% of participants in any round were excluded. Retained indicative questions were further ranked based on the rating score in the final Delphi round. The final research priorities were ratified by the Delphi expert group.

RESULTS

There were 1318 responses from 516 people in the initial survey, from which 71 indicative questions were formed, of which 68 entered the modified Delphi process. Eleven 'highest priority' research questions were short listed, covering themes of pain management; training and assessment; clinical practice and efficacy; technology and equipment.

CONCLUSIONS

We prioritised unanswered research questions in regional anaesthesia. These will inform a coordinated global research strategy for regional anaesthesia and direct investigators to address high-priority areas.

Artificial intelligence for ultrasound scanning in regional anaesthesia: a scoping review of the evidence from multiple disciplines

BACKGROUND

Artificial intelligence (AI) for ultrasound scanning in regional anaesthesia is a rapidly developing interdisciplinary field. There is a risk that work could be undertaken in parallel by different elements of the community but with a lack of knowledge transfer between disciplines, leading to repetition and diverging methodologies. This scoping review aimed to identify and map the available literature on the accuracy and utility of AI systems for ultrasound scanning in regional anaesthesia.

METHODS

A literature search was conducted using Medline, Embase, CINAHL, IEEE Xplore, and ACM Digital Library. Clinical trial registries, a registry of doctoral theses, regulatory authority databases, and websites of learned societies in the field were searched. Online commercial sources were also reviewed.

RESULTS

In total, 13,014 sources were identified; 116 were included for full-text review. A marked change in AI techniques was noted in 2016-17, from which point on the predominant technique used was deep learning. Methods of evaluating accuracy are variable, meaning it is impossible to compare the performance of one model with another. Evaluations of utility are more comparable, but predominantly gained from the simulation setting with limited clinical data on efficacy or safety. Study methodology and reporting lack standardisation.

CONCLUSIONS

There is a lack of structure to the evaluation of accuracy and utility of AI for ultrasound scanning in regional anaesthesia, which hinders rigorous appraisal and clinical uptake. A framework for consistent evaluation is needed to inform model evaluation, allow comparison between approaches/models, and facilitate appropriate clinical adoption.

Dexmedetomidine Prolongs Lidocaine Intravenous Regional Anesthesia in Rats by Blocking the Hyperpolarization-Activated Cation Current

Purpose

Intravenous regional anesthesia (IVRA) using lidocaine provides effective localized analgesia but its duration is limited. The mechanism by which dexmedetomidine enhances lidocaine IVRA is unclear but may involve modulation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels.

Materials and Methods

Lidocaine IVRA with varying dexmedetomidine concentrations was performed in the tails of Sprague-Dawley rats. Tail-flick and tail-clamping tests assessed IVRA analgesia and anesthesia efficacy and duration. Contributions of α2 adrenergic receptors and HCN channels were evaluated by incorporating an α adrenergic receptor antagonist, the HCN channel inhibitor ZD7288, and the HCN channel agonist forskolin. Furthermore, whole-cell patch clamp electrophysiology quantified the effects of dexmedetomidine on HCN channels mediating hyperpolarization-activated cation current (Ih) in isolated dorsal root ganglion neurons.

Results

Dexmedetomidine dose-dependently extended lidocaine IVRA duration and analgesia, unaffected by α2 receptor blockade. The HCN channel inhibitor ZD7288 also prolonged lidocaine IVRA effects, while the HCN channel activator forskolin shortened effects. In dorsal root ganglion neurons, dexmedetomidine concentration-dependently inhibited Ih amplitude and shifted the voltage-dependence of HCN channel activation.

Conclusion

Dexmedetomidine prolongs lidocaine IVRA duration by directly inhibiting HCN channel activity, independent of α2 adrenergic receptor activation. This HCN channel inhibition represents a novel mechanism underlying the anesthetic and analgesic adjuvant effects of dexmedetomidine in IVRA.

Pecto-intercostal Fascial Plane Block: A Novel Technique for Analgesia in Patients with Sternal Dehiscence

ABSTRACT

Sternal wound complications following sternotomy need a multidisciplinary approach in high-risk postoperative cardiac surgical patients. Poorly controlled pain during surgical management of such wounds increases cardiovascular stress and respiratory complications. Multimodal analgesia including intravenous opioids, non-opioid analgesics, and regional anesthesia techniques, like central neuraxial blocks and fascial plane blocks, have been described. Pecto-intercostal fascial plane block (PIFB), a novel technique, has been effectively used in patients undergoing cardiac surgery. Under ultrasound (US) guidance PIFB is performed with the aim of depositing local anesthetic between two superficial muscles, namely the pectoralis major muscle and the external intercostal muscle. The authors report a series of five cases where US-guided bilateral PIFB was used in patients undergoing sternal wound debridement. Patients had excellent analgesia intraoperatively as well as postoperatively for 24 hours with minimal requirement of supplemental analgesia. None of the patients experienced complications due to PIFB administration. The authors concluded that bilateral PIFB can be effectively used as an adjunct to multimodal analgesia with general anesthesia and as a sole anesthesia technique in selected cases of sternal wound debridement.

Anesthetic Considerations in Combined TAVR and Aortic Endovascular Procedures, a Case Report

ABSTRACT

We report a case of simultaneous transcatheter aortic valve replacement and endovascular aneurysm repair. Our aim was to advocate the role of local and regional anesthesia as a key contributor in maintaining hemodynamic stability and avoiding abrupt blood pressure change. Endovascular combined procedures are gaining popularity for their numerous advantages. Nevertheless, they carry significant risks for their hemodynamic implications. It is imperative to acknowledge the modifications occurring after each correction and act accordingly. Different anesthesia approaches can dramatically influence hemodynamics; among all, we found local and regional anesthesia would better serve this objective.

Comparison of diffusion ranges at different local anesthetic volumes during superior laryngeal nerve block

OBJECTIVES

Ultrasound-guided superior laryngeal nerve (SLN) block is a practical and painless approach to avoid the hemodynamic stress response during endotracheal intubation and relieve sore throat after laryngeal surgery. The main purpose of this study was to establish an optimal dosage of local anesthetic when performing SLN block to help anesthetists balance analgesia and side effects.

METHODS

Twenty fresh larynx specimens were obtained immediately after resection and then injected with 2-, 3-, 4-, or 5- mL of a lidocaine-blue dye mixture at bilateral SLN puncture sites. Superficial areas of deposited blue dye were measured. Dye leakage and surrounding dyed tissue were recorded. Another 40 patients were included in the ultrasound investigation. Distances between the internal branch of the SLN (iSLN) and adjacent structures were calculated.

RESULTS

The dye spread area was greater with the administration of larger doses, especially to the visceral space. A 2- or 3-mL injection of local anesthetic was sufficient to infiltrate the SLN gap. A higher incidence of dye leaking out of the thyrohyoid membrane and anterior epiglottis space was observed; furthermore, there was substantially more dyed hyoid/thyroid cartilage with 4 and 5 mL of injected dye mixture than 2 mL. There was no significant difference between the specimen and ultrasound measurements of for length of iSLN-adjacent structures.

CONCLUSIONS

In the Chinese population, 2- or 3- mL of local anesthetic is a safe dose during SLN block. A larger volume could overflow from the cavity to cause complications. The thyrohyoid membrane combined with the superior laryngeal artery is a reliable target for positioning the iSLN during ultrasound-guided regional anesthesia.