Differential nerve blockade to explain anterior thoracic analgesia without sensory blockade after an erector spinae plane block may be wishful thinking.

Ultrasound-guided erector spinae plane block (ESPB) is currently used as a component of multimodal analgesic regimen in a multitude of indications but the mechanism by which it produces anterior thoracic analgesia remains a subject of controversy. This is primarily the result of ESPB's failure to consistently produce cutaneous sensory blockade (to pinprick and cold sensation) over the anterior hemithorax. Nevertheless, ESPB appears to provide 'clinically meaningful analgesia' in various clinical settings. Lately, it has been proposed that the discrepancy between clinical analgesia and cutaneous sensory blockade could be the result of differential nerve blockade at the level of the dorsal root ganglion. In particular, it is claimed that at a low concentration of local anesthetic, the C nerve fibers would be preferentially blocked than the Aδ nerve fibers. However, the proposal that isolated C fiber mediated analgesia with preserved Aδ fiber mediated cold and pinprick sensation after an ESPB is unlikely, has never been demonstrated and, thus, without sufficient evidence, cannot be attributed to the presumed analgesic effects of an ESPB.

Spinal sonography and central neuraxial blocks.

Central neuraxial blocks (CNBs), which include spinal, epidural, and combined spinal epidural injections, are indispensable techniques in the anesthesiologist's armamentarium. Indeed, in scenarios such as when dealing with the obstetric population, patients with obesity, or patients having respiratory compromise (e.g., lung disease or scoliosis), CNBs are the mainstay for anesthesia and/or analgesia. Traditionally, CNBs are performed using anatomical landmarks, which are simple, easy to master, and exceptionally successful in most cases. Nevertheless, there are notable limitations with this approach, especially in scenarios where CNBs are considered mandatory and vital. Any limitation of an anatomic landmark-based approach is an opportunity for an ultrasound-guided (USG) technique. This has become particularly true for CNBs, where recent advances in ultrasound technology and research data have addressed many of the shortcomings of the traditional anatomic landmark-based approaches. This article reviews the ultrasound imaging of the lumbosacral spine and its application for CNBs.

Ultrasound-guided selective trunk block: Evaluation of ipsilateral sensorimotor block dynamics, hemidiaphragmatic function and efficacy for upper extremity surgery. A single-centre cohort study.

BACKGROUND: Selectively locating and blocking the individual trunks of the brachial plexus with small volumes of local anaesthetic, a selective trunk block (SeTB), may produce anaesthesia of the entire upper extremity except for the T2 dermatome. OBJECTIVE: This study aimed to evaluate the effects of an ultrasound-guided (USG) SeTB on ipsilateral sensorimotor block dynamics, hemidiaphragmatic function, and efficacy as an all-purpose regional anaesthetic technique for upper extremity surgery. DESIGN: Prospective cohort study. SETTING: Single-centre, university hospital in Hong Kong, China from February 2021 to July 2021. PATIENTS: Thirty patients (aged 53.2 ±â€Š14.8 years and BMI 23.8 ±â€Š3.6 kg m - 2 ), ASA physical status I to III, scheduled for upper extremity surgery under a brachial plexus block. INTERVENTIONS: USG SeTB with 25 ml (7, 8 and 10 ml to the superior, middle and inferior trunks, respectively) of a 1 : 1 mixture of 2% lidocaine with 1 : 200 000 epinephrine and 0.5% levobupivacaine. MAIN OUTCOME MEASURES: Ipsilateral sensorimotor blockade of the suprascapular (only motor), axillary, radial, ulnar, median and musculocutaneous nerves were assessed at regular intervals for 45 min. Ipsilateral hemidiaphragmatic excursion was also measured, at 30 min after the SeTB, using M-mode ultrasound. The SeTB was considered a success if it was possible to complete surgery without any rescue analgesia or conversion to general anaesthesia. RESULTS: Complete motor blockade of the suprascapular nerve was achieved in median [range] 5 [5 to 15] min. Complete sensory and motor blockade were achieved in all the other 5 nerves in 17.5 [10 to 30] and 15 [10 to 30] min respectively. The SeTB was successful in 93% and ipsilateral hemidiaphragmatic paresis (HDP) was present in 82%, of patients. CONCLUSION: SeTB produces sensorimotor blockade of the entire upper extremity, causes ipsilateral HDP, and is effective as the sole anaesthetic for surgery from the proximal humerus to the hand. TRIAL REGISTRION: ClinicalTrials.gov, Trial Registration No: NCT04752410, Date submitted for Registration: 09 February 2021, Date first posted: 12 February 2021, Dates of patient enrolment: 19 February 2021 to 27 July 2021 ( https://clinicaltrials.gov/ct2/show/NCT04752410 ).

HDL cholesterol levels and susceptibility to COVID-19.

BACKGROUND: Host cell-membrane cholesterol, an important player in viral infections, is in constant interaction with serum high-density lipoprotein-cholesterol (HDL-C) and low-density lipoprotein-cholesterol (LDL-C). Low serum lipid levels during hospital admission are associated with COVID-19 severity. However, the effect of antecedent serum lipid levels on SARS-CoV-2 infection risk has not been explored. METHODS: From our retrospective cohort from the Arkansas Clinical Data-Repository, we used log-binomial regression to assess the risk of SARS-CoV-2 infection among the trajectories of lipid levels during the 2 years antecedent to COVID-19 testing, identified using group-based-trajectory modelling. We used mixed-effects linear regression to assess the serum lipid level trends followed up to the time of, and 2-months following COVID-19 testing. FINDINGS: Among the 11001 individuals with a median age of 59 years (IQR 46-70), 1340 (12.2%) tested positive for COVID-19. The highest trajectory for antecedent serum HDL-C was associated with the lowest SARS-CoV-2 infection risk (RR 0.63, 95%CI 0.46-0.86). Antecedent serum LDL-C, total cholesterol (TC), and triglycerides (TG) were not independently associated with SARS-CoV-2 infection risk. In COVID-19 patients, serum HDL-C (-7.7, 95%CI -9.8 to -5.5 mg/dL), and LDL-C (-6.29, 95%CI -12.2 to -0.37 mg/dL), but not TG levels, decreased transiently at the time of testing. INTERPRETATION: Higher antecedent serum HDL-C, but not LDL-C, TC, or TG, levels were associated with a lower SARS-CoV-2 infection risk. Serum HDL-C, and LDL-C levels declined transiently at the time of infection. Further studies are needed to determine the potential role of lipid-modulating therapies in the prevention and management of COVID-19. FUNDING: Research reported in this publication was supported by the National Center for Advancing Translational Sciences of the National Institutes of Health under Award Number UL1 TR003107.

Real-Time Ultrasound-Guided Spinal Injection Using a Transverse In-Plane Dependent Technique: A Case Series.

Ultrasound-guided (USG) spinal injection is generally performed using a paramedian sagittal oblique scan, with the patient in the lateral decubitus position, and the spinal needle inserted in-plane from the nondependent side. This report evaluated the feasibility of performing USG spinal injection, using an alternative transverse interspinous scan with in-plane needle insertion, a transverse in-plane dependent (TIPD) technique, in 30 adult patients undergoing elective surgery under spinal anesthesia. Dural puncture was successfully achieved in 29 of 30 (96.6%) patients with 2 (1-3) attempts in 5 (4-8) minutes using the TIPD technique. Multiple interspinous osteophytes accounted for technical failure in 1 patient.

The Retro Superior Costotransverse Ligament Space as a New Target for Ultrasound-Guided Intertransverse Process Block: A Report of 2 Cases.

An intertransverse process block (ITPB) is a paraspinal thoracic nerve block technique, where the local anesthetic (LA) is injected into the thoracic intertransverse tissue complex posterior to the superior costotransverse ligament (SCTL). Although an ITPB can be ultrasound-guided, it is performed using surrogate bony landmarks without even identifying the SCTL. This report describes a transverse ultrasound imaging technique to identify the retro-SCTL space and perform an ITPB with a retro-SCTL space injection, in 2 patients undergoing video-assisted thoracoscopic surgery. The resultant bilateral, symmetrical, thoracolumbar anesthesia was consistent with epidural spread of the LA and effective for perioperative analgesia.

Ultrasound-guided selective trunk block (SeTB): a cadaver anatomic study to evaluate the spread of dye after a simulated injection.

BACKGROUND AND OBJECTIVES: Recent reports suggest that a selective trunk block (SeTB) can produce sensorimotor blockade of the entire upper extremity, except for the T2 dermatome. There are no data demonstrating the anatomic mechanism of SeTB. This cadaver study aimed to evaluate the spread of an injectate after a simulated ultrasound-guided (USG) SeTB. METHODS: USG SeTB (n=7) was performed on both sides of the neck in four adult human cadavers with 25 mL of 0.1% methylene blue dye. Anatomic dissection was performed to document staining (deep, faint, and no stain) of the various elements of the brachial plexus from the level of the roots to the cords, including the phrenic, dorsal scapular, and long thoracic nerves. Only structures that were deeply stained were defined as being affected by the SeTB. RESULTS: All the trunks and divisions of the brachial plexus, as well as the ventral rami of C5-C7 and suprascapular nerve, were deeply stained in all (100%) the simulated injections. The ventral rami of C8 and T1 (86%), dorsal scapular and long thoracic nerve (71%), and the phrenic nerve (57%) were also deeply stained in a substantial number of the injections. CONCLUSION: This cadaver study demonstrates that an USG SeTB consistently affects all the trunks and divisions of the brachial plexus, as well as the suprascapular nerve. This study also establishes that SeTB may not be phrenic nerve sparing. Future research to evaluate the safety and efficacy of SeTB as an all-purpose brachial plexus block technique for upper extremity surgery is warranted. TRIAL REGISTRATION NUMBER: Registered at https://www.thaiclinicaltrials.org on December 13, 2021 under the trial registration number TCTR20211213005.

Association of Lipid Levels With COVID-19 Infection, Disease Severity and Mortality: A Systematic Review and Meta-Analysis.

Background: Coronavirus disease 2019 (COVID-19) ranges from asymptomatic infection to severe illness. Cholesterol in the host cell plasma membrane plays an important role in the SARS-CoV-2 virus entry into cells. Serum lipids, especially low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), are in constant interaction with the lipid rafts in the host cell membranes and can modify the interaction of virus with host cells and the resultant disease severity. Recent studies on serum lipid levels and COVID-19 disease severity lack consistency. Objectives: Our systematic review and meta-analysis compared the serum levels of total cholesterol (TC), LDL-C, HDL-C, and triglycerides (TG) between (1) COVID-19 patients vs. healthy controls; (2) severe vs. non-severe COVID-19 disease; (3) deceased vs. surviving COVID-19 patients. Methods: PRISMA guidelines were followed. We included peer-reviewed articles on observational (case-control and cohort) studies from PubMed and Embase published from the database inception until September 1, 2021. We used random-effects meta-analysis for pooled mean-differences (pMD) in lipid levels (mg/dL) for the above groups. Results: Among 441 articles identified, 29 articles (26 retrospective and 3 prospective cohorts), with an aggregate of 256,721 participants, were included. COVID-19 patients had lower TC (pMD-14.9, 95%CI-21.6 to -8.3) and HDL-C (pMD-6.9, 95%CI -10.2 to -3.7) levels (mg/dL). Severe COVID-19 patients had lower TC (pMD-10.4, 95%CI -18.7 to -2.2), LDL-C (pMD-4.4, 95%CI -8.4 to -0.42), and HDL-C (pMD-4.4, 95%CI -6.9 to -1.8) at admission compared to patients with non-severe disease. Deceased patients had lower TC (pMD-14.9, 95%CI -21.6 to -8.3), LDL-C (pMD-10.6, 95%CI -16.5 to -4.6) and HDL-C (pMD-2.5, 95%CI -3.9 to -1.0) at admission. TG levels did not differ based on COVID-19 severity or mortality. No publication bias was noted. Conclusion: We demonstrated lower lipid levels in patients with COVID-19 infection and an association with disease severity and mortality. Their potential role in COVID-19 pathogenesis and their utility as prognostic factors require further investigation.

Male Sex Is Associated With Worse Microbiological and Clinical Outcomes Following Tuberculosis Treatment: A Retrospective Cohort Study, a Systematic Review of the Literature, and Meta-analysis.

BACKGROUND: Although the incidence of tuberculosis is higher in men than in women, the relationship of sex with tuberculosis treatment outcomes has not been adequately studied. METHODS: We performed a retrospective cohort study and a systematic review and meta-analysis of observational studies during the last 10 years to assess sex differences in clinical and microbiological outcomes in tuberculosis. RESULTS: In our cohort of 2894 Taiwanese patients with drug-susceptible pulmonary tuberculosis (1975 male and 919 female), male patients had higher adjusted hazards of 9-month mortality due to all causes (hazard ratio, 1.43 [95% confidence interval (CI), 1.03-1.98]) and infections (1.70 [1.09-2.64]) and higher adjusted odds of 2-month sputum culture positivity (odds ratio [OR], 1.56 [95% CI, 1.05-2.33]) compared with female patients. Smear positivity at 2 months did not differ significantly (OR, 1.27 [95% CI, .71-2.27]) between the sexes. Among 7896 articles retrieved, 398 were included in our systematic review describing a total of 3 957 216 patients. The odds of all-cause mortality were higher in men than in women in the pooled unadjusted (OR, 1.26 [95% CI, 1.19-1.34]) and adjusted (1.31 [1.18-1.45]) analyses. Men had higher pooled odds of sputum culture (OR, 1.44 [95% CI, 1.14-1.81]) and sputum smear (1.58 [1.41-1.77]) positivity, both at the end of the intensive phase and on completion of treatment. CONCLUSIONS: Our retrospective cohort showed that male patients with tuberculosis have higher 9-month all-cause and infection-related mortality, with higher 2-month sputum culture positivity after adjustment for confounding factors. In our meta-analysis, male patients showed higher all-cause and tuberculosis-related mortality and higher sputum culture and smear positivity rates during and after tuberculosis treatment.

High-definition ultrasound imaging defines the paraneural sheath and fascial compartments surrounding the cords of the brachial plexus at the costoclavicular space and lateral infraclavicular fossa.

BACKGROUND AND OBJECTIVES: The paraneural sheath is a multilayered network of collagen fibers that surround the brachial plexus. Currently, there are no sonographic data on the paraneural sheath of the brachial plexus, which this study aimed to evaluate. METHODS: Ultrasound imaging datasets of 100 patients who received a costoclavicular brachial plexus block, using high-definition ultrasound imaging, were retrospectively reviewed. Video files, representing sonograms before and after the local anesthetic injection, from the costoclavicular space and lateral infraclavicular fossa were collated and reviewed by three experienced anesthesiologists. Frequency (yes/no) of ultrasound visualization of the paraneural sheath, septum, and the anterior and posterior compartments was assessed. Representative sonograms from the costoclavicular space and lateral infraclavicular fossa were visually correlated with archived cadaver microanatomic sections from the same location. RESULTS: Datasets of the 98 patients who achieved surgical anesthesia were evaluated. The paraneural sheath, septum, and the anterior and posterior compartments were visualized in 17.3%, 7.1%, 5.1% and 5.1%, respectively, at the costoclavicular space before the brachial plexus block; this contrasts (p<0.001) with their visibility post-block (94.9%, 75.5%, 75.5% and 75.5%, respectively). At the lateral infraclavicular fossa, the corresponding visibility of these structures post-block were 67.7%, 81.5%, 81.5% and 81.5%, respectively. Ultrasound images of the paraneural sheath and septum correlated well with that in the cadaver microanatomic sections. CONCLUSION: We have demonstrated the paraneural sheath and fascial compartments surrounding the cords of the brachial plexus at the costoclavicular space and lateral infraclavicular fossa using high-definition ultrasound imaging. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04370184), (https://www.clinicaltrials.gov/).