The response of Canada's clinical health research ecosystem to the COVID-19 pandemic.

BACKGROUND: The response of Canada's research community to the COVID-19 pandemic provides a unique opportunity to examine the country's clinical health research ecosystem. We sought to describe patterns of enrolment across Canadian Institutes of Health Research (CIHR)-funded studies on COVID-19. METHODS: We identified COVID-19 studies funded by the CIHR and that enrolled participants from Canadian acute care hospitals between January 2020 and April 2023. We collected information on study-and site-level variables from study leads, site investigators, and public domain sources. We described and evaluated factors associated with cumulative enrolment. RESULTS: We obtained information for 23 out of 26 (88%) eligible CIHR-funded studies (16 randomized controlled trials [RCTs] and 7 cohort studies). The 23 studies were managed by 12 Canadian and 3 international coordinating centres. Of 419 Canadian hospitals, 97 (23%) enrolled a total of 28 973 participants - 3876 in RCTs across 78 hospitals (median cumulative enrolment per hospital 30, interquartile range [IQR] 10-61), and 25 097 in cohort studies across 62 hospitals (median cumulative enrolment per hospital 158, IQR 6-348). Of 78 hospitals recruiting participants in RCTs, 13 (17%) enrolled 50% of all RCT participants, whereas 6 of 62 hospitals (9.7%) recruited 54% of participants in cohort studies. INTERPRETATION: A minority of Canadian hospitals enrolled the majority of participants in CIHR-funded studies on COVID-19. This analysis sheds light on the Canadian health research ecosystem and provides information for multiple key partners to consider ways to realize the full research potential of Canada's health systems.

Chronic Diarrhea Caused by a Klebsiella oxytoca Toxin Producer Strain Following Antibiotic-Associated Hemorrhagic Colitis: Successful Treatment by Fecal Microbiota Transplant.

Klebsiella oxytoca is a gram-negative bacterium found in fecal microbiota and known to cause several infections in humans, including antibiotic-associated hemorrhagic colitis. We present here a case of colitis caused by K. oxytoca toxin-producing strains that evolved in chronic diarrhea successfully treated by fecal microbiota transplant.

Multicenter Evaluation of Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) Spectroscopy-Based Method for Rapid Identification of Clinically Relevant Yeasts.

Fourier transform infrared (FTIR) spectroscopy has demonstrated applicability as a reagent-free whole-organism fingerprinting technique for both microbial identification and strain typing. For routine application of this technique in microbiology laboratories, acquisition of FTIR spectra in the attenuated total reflectance (ATR) mode simplifies the FTIR spectroscopy workflow, providing results within minutes after initial culture without prior sample preparation. In our previous central work, 99.7% correct species identification of clinically relevant yeasts was achieved by employing an ATR-FTIR-based method and spectral database developed by our group. In this study, ATR-FTIR spectrometers were placed in 6 clinical microbiology laboratories over a 16-month period and were used to collect spectra of routine yeast isolates for on-site identification to the species level. The identification results were compared to those obtained from conventional biochemical tests and/or matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Isolates producing discordant results were reanalyzed by routine identification methods, ATR-FTIR spectroscopy, and PCR gene sequencing of the D1/D2 and internal transcribed spacer (ITS) regions. Among the 573 routine clinical yeast isolates collected and identified by the ATR-FTIR-based method, 564 isolates (98.4%) were correctly identified at the species level, while the remaining isolates were inconclusive with no misidentifications. Due to the low prevalence of Candida auris in routine isolates, additional randomly selected C. auris (n = 24) isolates were obtained for evaluation and resulted in 100% correct identification. Overall, the data obtained in our multicenter evaluation study using multiple spectrometers and system operators indicate that ATR-FTIR spectroscopy is a reliable, cost-effective yeast identification technique that provides accurate and timely (∼3 min/sample) species identification promptly after the initial culture.

Evaluation of water gargle samples for SARS-CoV-2 detection using Abbott ID NOW COVID-19 assay.

The Abbott ID NOW™ COVID-19 assay has been shown as a reliable and sensitive alternative to reverse transcription-polymerase chain reaction (RT-PCR) testing from nasopharyngeal or nasal samples in symptomatic patients. Water gargle is an acceptable noninvasive alternative specimen for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) detection by RT-PCR. The objective of this study was to evaluate the performance of water gargle samples for the detection of SARS-CoV-2 using the ID NOW. Residual gargle samples were randomly selected among positive standard of care (SOC)-nucleic acid amplification test (NAAT) samples. For testing on ID NOW, the manufacturer's instructions were followed, except for the specimen addition step: 500 µl of the gargle specimen was added to the blue sample receiver with a pipette and gently mixed. Among the 202 positive samples by SOC-NAAT, 185 were positive by ID NOW (positive percent agreement [PPA]) = 91.6% (95% confidence interval [CI]: 86.9-95.0). For the 17 discordant samples, cycle threshold (Ct ) values were all ≥31.0. The PPA was significantly lower among asymptomatic patients (84.4%; 95% CI: 73.2-92.3) versus symptomatic patients (95.2%; 95% CI: 89.8-98.2). The performance of the ID NOW for the detection of SARS-CoV-2 infection on gargle samples is excellent when Ct values are <31.0 and for patients that have COVID-19 compatible symptoms.

Comparison of saliva with oral and nasopharyngeal swabs for SARS-CoV-2 detection on various commercial and laboratory-developed assays.

The accurate laboratory detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a crucial element in the fight against coronavirus disease 2019 (COVID-19). Reverse transcription-polymerase chain reaction testing on combined oral and nasopharyngeal swab (ONPS) suffers from several limitations, including the need for qualified personnel, the discomfort caused by invasive nasopharyngeal sample collection, and the possibility of swab and transport media shortage. Testing on saliva would represent an advancement. The aim of this study was to compare the concordance between saliva samples and ONPS for the detection of SARS-CoV-2 on various commercial and laboratory-developed tests (LDT). Individuals were recruited from eight institutions in Quebec, Canada, if they had SARS-CoV-2 RNA detected on a recently collected ONPS, and accepted to provide another ONPS, paired with saliva. Assays available in the different laboratories (Abbott RealTime SARS-CoV-2, Cobas® SARS-CoV-2, Simplexa™ COVID-19 Direct, Allplex™ 2019-nCoV, RIDA®GENE SARS-CoV-2, and an LDT preceded by three different extraction methods) were used to determine the concordance between saliva and ONPS results. Overall, 320 tests were run from a total of 125 saliva and ONPS sample pairs. All assays yielded similar sensitivity when saliva was compared to ONPS, with the exception of one LDT (67% vs. 93%). The mean difference in cycle threshold (∆C t ) was generally (but not significantly) in favor of the ONPS for all nucleic acid amplification tests. The maximum mean ∆​​​​​C t was 2.0, while individual ∆C t varied importantly from -17.5 to 12.4. Saliva seems to be associated with sensitivity similar to ONPS for the detection of SARS-CoV-2 by various assays.

SARS-CoV-2 seroprevalence in health care workers from 10 hospitals in Quebec, Canada: a cross-sectional study.

BACKGROUND: The COVID-19 pandemic has disproportionately affected health care workers. We sought to estimate SARS-CoV-2 seroprevalence among hospital health care workers in Quebec, Canada, after the first wave of the pandemic and to explore factors associated with SARS-CoV-2 seropositivity. METHODS: Between July 6 and Sept. 24, 2020, we enrolled health care workers from 10 hospitals, including 8 from a region with a high incidence of COVID-19 (the Montréal area) and 2 from low-incidence regions of Quebec. Eligible health care workers were physicians, nurses, orderlies and cleaning staff working in 4 types of care units (emergency department, intensive care unit, COVID-19 inpatient unit and non-COVID-19 inpatient unit). Participants completed a questionnaire and underwent SARS-CoV-2 serology testing. We identified factors independently associated with higher seroprevalence. RESULTS: Among 2056 enrolled health care workers, 241 (11.7%) had positive SARS-CoV-2 serology. Of these, 171 (71.0%) had been previously diagnosed with COVID-19. Seroprevalence varied among hospitals, from 2.4% to 3.7% in low-incidence regions to 17.9% to 32.0% in hospitals with outbreaks involving 5 or more health care workers. Higher seroprevalence was associated with working in a hospital where outbreaks occurred (adjusted prevalence ratio 4.16, 95% confidence interval [CI] 2.63-6.57), being a nurse or nursing assistant (adjusted prevalence ratio 1.34, 95% CI 1.03-1.74) or an orderly (adjusted prevalence ratio 1.49, 95% CI 1.12-1.97), and Black or Hispanic ethnicity (adjusted prevalence ratio 1.41, 95% CI 1.13-1.76). Lower seroprevalence was associated with working in the intensive care unit (adjusted prevalence ratio 0.47, 95% CI 0.30-0.71) or the emergency department (adjusted prevalence ratio 0.61, 95% CI 0.39-0.98). INTERPRETATION: Health care workers in Quebec hospitals were at high risk of SARS-CoV-2 infection, particularly in outbreak settings. More work is needed to better understand SARS-CoV-2 transmission dynamics in health care settings.

Hyperactivation of monocytes and macrophages in MCI patients contributes to the progression of Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the most common neurodegenerative disease ultimately manifesting as clinical dementia. Despite considerable effort and ample experimental data, the role of neuroinflammation related to systemic inflammation is still unsettled. While the implication of microglia is well recognized, the exact contribution of peripheral monocytes/macrophages is still largely unknown, especially concerning their role in the various stages of AD. OBJECTIVES: AD develops over decades and its clinical manifestation is preceded by subjective memory complaints (SMC) and mild cognitive impairment (MCI); thus, the question arises how the peripheral innate immune response changes with the progression of the disease. Therefore, to further investigate the roles of monocytes/macrophages in the progression of AD we assessed their phenotypes and functions in patients at SMC, MCI and AD stages and compared them with cognitively healthy controls. We also conceptualised an idealised mathematical model to explain the functionality of monocytes/macrophages along the progression of the disease. RESULTS: We show that there are distinct phenotypic and functional changes in monocyte and macrophage populations as the disease progresses. Higher free radical production upon stimulation could already be observed for the monocytes of SMC patients. The most striking results show that activation of peripheral monocytes (hyperactivation) is the strongest in the MCI group, at the prodromal stage of the disease. Monocytes exhibit significantly increased chemotaxis, free radical production, and cytokine production in response to TLR2 and TLR4 stimulation. CONCLUSION: Our data suggest that the peripheral innate immune system is activated during the progression from SMC through MCI to AD, with the highest levels of activation being in MCI subjects and the lowest in AD patients. Some of these parameters may be used as biomarkers, but more holistic immune studies are needed to find the best period of the disease for clinical intervention.

Bayesian Evaluation of Solana HSV 1+2/VZV Assay Compared to Viral Culture and Commercial PCR Assay for Cutaneous or Mucocutaneous Specimens.

Results from the Solana HSV 1+2/VZV assay for the detection of herpes simplex virus 1 (HSV-1), HSV-2, and varicella-zoster virus (VZV) in cutaneous or mucocutaneous specimens were compared with that of viral culture and a commercial PCR assay (RealStar alpha herpesvirus PCR kit). Three hundred two mucocutaneous specimens, for which HSV-1, HSV-2, or VZV viral culture or PCR detection have been requested, were randomly selected and prospectively processed on the Solana assay and viral culture or the RealStar assay. Discordant results between culture and the Solana assay were further analyzed using the RealStar assay. A Bayesian latent class model was developed to estimate the performance of each method. Viral culture detected 123 positive specimens (85 HSV-1, 36 HSV-2, and 2 VZV), while the Solana assay detected 27 additional positive specimens (4 HSV-1, 11 HSV-2, and 12 VZV), in agreement with the RealStar PCR assay. The estimated sensitivity of the Solana assay according to our model was 92.7% to 98.7%, 87.1% to 97.8%, and 94.9% to 98.8% (95% confidence interval [CI]) for HSV-1 HSV-2, and VZV, respectively, while the estimated sensitivity of viral culture was 85.2% to 95.0%, 73.6% to 89.6%, and 30.9% to 45.8% (95% CI), respectively. A nonsignificant tendency toward increased sensitivity was noted for the Solana assay compared with culture for HSV-1 and HSV-2, and the Solana assay was significantly more sensitive than culture for the detection of VZV. The Solana assay performed comparably to the RealStar assay. Processing time was reduced with the Solana assay compared with viral culture.

Severe MRSA Enterocolitis Caused by a Strain Harboring Enterotoxins D, G, and I.

We describe a case of methicillin-resistant Staphylococcus aureus (MRSA) enterocolitis in a healthy adult with previous antibiotic exposure. Colonoscopy revealed diffuse colitis and mild ileitis without ulceration. Stool cultures demonstrated abundant growth of MRSA and absent normal flora. Oral vancomycin treatment was effective and seems to be the consensus choice for therapy.

Molecular Epidemiology of a Vancomycin-Intermediate Heteroresistant Staphylococcus epidermidis Outbreak in a Neonatal Intensive Care Unit.

Coagulase-negative staphylococci (CoNS) have become the leading cause of bloodstream infections (BSIs) in intensive care units (ICUs), particularly in premature neonates. Vancomycin-intermediate heteroresistant CoNS (hVICoNS) have been identified as sources of BSIs worldwide, and their potential to emerge as significant pathogens in the neonatal ICU (NICU) remains uncertain. This study describes the molecular epidemiology of an outbreak of vancomycin-heteroresistant (hV) Staphylococcus epidermidis central-line-associated BSI (CLABSI) in a single tertiary care NICU and compares it to a second tertiary care NICU that had not been associated with an outbreak. Between November 2009 and April 2014, 119 S. epidermidis CLABSIs were identified in two tertiary care NICUs in Quebec, Canada. Decreased vancomycin susceptibility was identified in about 88% of all collected strains using Etest methods. However, discrepancies were found according to the Etest and population analysis profiling-area under the concentration-time curve (PAP-AUC) methods used. All strains were susceptible to linezolid, and a few isolates were nonsusceptible to daptomycin. Great genetic diversity was observed within the collection, with 31 pulsed-field gel electrophoresis (PFGE) patterns identified. The outbreak strains were all determined to be heteroresistant to vancomycin and were polyclonal. The study identified two major clones, PFGE patterns E and G, which were found in both NICUs across the 5-year study period. This suggests the persistence of highly successful clones that are well adapted to the hospital environment. hV S. epidermidis seems more common than currently realized in the NICU, and certain hV S. epidermidis clones can become endemic to the NICU. The reservoirs for these clones remain unknown at this time, and identification of the reservoirs is needed to better understand the impact of hV S. epidermidis in the NICU and to inform infection prevention strategies. In addition, there is a need to investigate and validate hV determination protocols for different species of CoNS.

A case report of a deep surgical site infection with Terrisporobacter glycolicus/T. Mayombei and review of the literature.

BACKGROUND: There are increasing data regarding Terrisporobacter glycolicus as an emerging anaerobic pathogen. However, the few published cases to date usually report it as part of a polymicrobial infection. Here, we describe the first reported monomicrobial surgical site infection with this bacterium. Identification methods, taxonomy, and clinical management of this rarely identified pathogen are also discussed. CASE PRESENTATION: A previously healthy 66-year-old sustained an open olecranon fracture of his left arm after trauma. He subsequently underwent open reduction and internal fixation (ORIF), with insertion of an olecranon locking plate and two locking screws. Ten days after surgery, the patient developed increasing pain at the surgical site and noted green discharge from the wound. Culture of the wound discharge yielded grew a pure Gram-positive anaerobe identified by the RapidANA® microbial identification system as C. difficile (profile 000010, 99.1 % probability). Reference laboratory testing identified the isolate as T. glycolicus/mayombei (previously designated as Clostridium glycolicum/mayombei) by 16S rRNA gene sequencing and as Clostridium glycolicum by MALDI-TOF mass spectrometry. The patient received an 8-week course of moxifloxacin and metronidazole with an excellent clinical response at 12 months' follow-up. CONCLUSIONS: We describe the case of a deep surgical site infection with T. glycolicus/mayombei (formerly known as Clostridium glycolicum and Clostridium mayombei, respectively), which extends our knowledge of the clinical spectrum of this pathogen. The isolate was misidentified by phenotypic identification methods.

Ultrasound-Guided Single-Injection Infraclavicular Block Versus Ultrasound-Guided Double-Injection Axillary Block: A Noninferiority Randomized Controlled Trial.

BACKGROUND: Single-injection ultrasound-guided infraclavicular block is a simple, reliable, and effective technique. A simplified double-injection ultrasound-guided axillary block technique with a high success rate recently has been described. It has the advantage of being performed in a superficial and compressible location, with a potentially improved safety profile. However, its effectiveness in comparison with single-injection infraclavicular block has not been established. We hypothesized that the double-injection ultrasound-guided axillary block would show rates of complete sensory block at 30 minutes noninferior to the single-injection ultrasound-guided infraclavicular block. METHODS: After approval by our research ethics committee and written informed consent, adults undergoing distal upper arm surgery were randomized to either group I, ultrasound-guided single-injection infraclavicular block, or group A, ultrasound-guided double-injection axillary block. In group I, 30 mL of 1.5% mepivacaine was injected posterior to the axillary artery. In group A, 25 mL of 1.5% mepivacaine was injected posteromedial to the axillary artery, after which 5 mL was injected around the musculocutaneous nerve. Primary outcome was the rate of complete sensory block at 30 minutes. Secondary outcomes were the onset of sensory and motor blocks, surgical success rates, performance times, and incidence of complications. All outcomes were assessed by a blinded investigator. The noninferiority of the double-injection ultrasound-guided axillary block was considered if the limits of the 90% confidence intervals (CIs) were within a 10% margin of the rate of complete sensory block of the infraclavicular block. RESULTS: At 30 minutes, the rate of complete sensory block was 79% in group A (90% CI, 71%-85%) compared with 91% in group I (90% CI, 85%-95%); the upper limit of CI of group A is thus included in the established noninferiority margin of 10%. The rate of complete sensory block was lower in group A (proportion difference of 12% [95% CI, 2-22]; P = 0.0091), as was surgical success rate (82% [95% CI, 74%-89%] vs 93% [95% CI, 86%-97%]; proportion difference of 11% [95% CI 1-20]; P = 0.0153). Sensory block onset also was slower in group A (log rank test P = 0.0020). Performance times were faster in group I (231 seconds [95% CI, 213-250]) than in group A (358 seconds [95% CI, 332-387]; P < 0.0001). No statistically significant difference was observed for vascular puncture, paresthesia during block performance, or procedure-related pain. No neurologic complication was noted at follow-up. CONCLUSIONS: We failed to demonstrate that the rate of complete sensory block of the double-injection axillary block is noninferior to the single-injection infraclavicular block. However, the rate of complete sensory block at 30 minutes is statistically significantly lower with the axillary block. The ultrasound-guided single-injection infraclavicular block thus seems to be the preferred technique over the axillary for upper arm anesthesia.

Earliest observation of the tetracycline destructase tet(X3).

Tigecycline is an antibiotic of last resort for infections with carbapenem-resistant Acinetobacter baumannii. Plasmids harboring variants of the tetracycline destructase gene tetX promote rising tigecycline resistance rates. We report the earliest observation of tet(X3) in a clinical strain predating tigecycline's commercialization, suggesting selective pressures other than tigecycline contributed to its emergence. IMPORTANCE: We present the earliest observation of a tet(X3)-positive bacterial strain, predating by many years the earliest reports of this gene so far. This finding is significant as tigecycline is an antibiotic of last resort for carbapenem-resistant Acinetobacter baumannii (CRAB), which the World Health Organization ranks as one of its top three critical priority pathogens, and tet(X3) variants have become the most prevalent genes responsible for enabling CRAB to become tigecycline resistant. Moreover, the tet(X3)-positive strain we report is the first and only to be found that predates the commercialization of tigecycline, an antibiotic that was thought to have contributed to the emergence of this resistance gene. Understanding the factors contributing to the origin and spread of novel antibiotic resistance genes is crucial to addressing the major global public health issue, which is antimicrobial resistance.

Distributed Statistical Analyses: A Scoping Review and Examples of Operational Frameworks Adapted to Health Analytics.

BACKGROUND: Data from multiple organizations are crucial for advancing learning health systems. However, ethical, legal, and social concerns may restrict the use of standard statistical methods that rely on pooling data. Although distributed algorithms offer alternatives, they may not always be suitable for health frameworks. OBJECTIVE: This paper aims to support researchers and data custodians in three ways: (1) providing a concise overview of the literature on statistical inference methods for horizontally partitioned data; (2) describing the methods applicable to generalized linear models (GLM) and assessing their underlying distributional assumptions; (3) adapting existing methods to make them fully usable in health settings. METHODS: A scoping review methodology was employed for the literature mapping, from which methods presenting a methodological framework for GLM analyses with horizontally partitioned data were identified and assessed from the perspective of applicability in health settings. Statistical theory was used to adapt methods and to derive the properties of the resulting estimators. RESULTS: From the review, 41 articles were selected, and six approaches were extracted for conducting standard GLM-based statistical analysis. However, these approaches assumed evenly and identically distributed data across nodes. Consequently, statistical procedures were derived to accommodate uneven node sample sizes and heterogeneous data distributions across nodes. Workflows and detailed algorithms were developed to highlight information-sharing requirements and operational complexity. CONCLUSIONS: This paper contributes to the field of health analytics by providing an overview of the methods that can be used with horizontally partitioned data, by adapting these methods to the context of heterogeneous health data and by clarifying the workflows and quantities exchanged by the methods discussed. Further analysis of the confidentiality preserved by these methods is needed to fully understand the risk associated with the sharing of summary statistics.

The Strain and the Clinical Outcome of Clostridioides difficile Infection: A Meta-analysis.

Background: The association between bacterial strains and clinical outcomes in Clostridioides difficile infection (CDI) has yielded conflicting results across studies. We conducted a systematic review and meta-analyses to assess the impact of these strains. Methods: Five electronic databases were used to identify studies reporting CDI severity, complications, recurrence, or mortality according to strain type from inception to June 2022. Random effect meta-analyses were conducted to assess outcome proportions and risk ratios (RRs). Results: A total of 93 studies were included: 44 reported recurrences, 50 reported severity or complications, and 55 reported deaths. Pooled proportions of complications were statistically comparable between NAP1/BI/R027 and R001, R078, and R106. Pooled attributable mortality was 4.8% with a gradation in patients infected with R014/20 (1.7%), R001 (3.8%), R078 (5.3%), and R027 (10.2%). Higher 30-day all-cause mortality was observed in patients infected with R001, R002, R027, and R106 (range, 20%-25%).NAP1/BI/R027 was associated with several unfavorable outcomes: recurrence 30 days after the end of treatment (pooled RR, 1.98; 95% CI, 1.02-3.84); admission to intensive care, colectomy, or CDI-associated death (1.88; 1.09-3.25); and 30-day attributable mortality (1.96; 1.23-3.13). The association between harboring the binary toxin gene and 30-day all-cause mortality did not reach significance (RR, 1.6 [0.9-2.9]; 7 studies). Conclusions: Numerous studies were excluded due to discrepancies in the definition of the outcomes and the lack of reporting of important covariates. NAP1/BI/R027, the most frequently reported and assessed strain, was associated with unfavorable outcomes. However, there were not sufficient data to reach significant conclusions on other strains.

Polyclonal outbreak of KPC-3-producing Enterobacter cloacae at a single hospital in Montreal, Quebec, Canada.

From September 2010 to December 2011, 26 KPC-3-producing Enterobacter cloacae isolates were identified from 16 patients at a single hospital. Analyses revealed the blaKPC gene to be localized on multiple plasmids in a diverse nonclonal E. cloacae genetic background. These findings highlight the potential complexity of a KPC outbreak at a single hospital.

Ultrasound-guided regional anesthesia for upper limb surgery.

PURPOSE: The purpose of this module is to review the main ultrasound-guided approaches used for regional anesthesia of the upper limb. PRINCIPAL FINDINGS: The anatomical configuration of the upper limb, with nerves often bundled around an artery, makes regional anesthesia of the arm both accessible and reliable. In-depth knowledge of upper limb anatomy is required to match the blocked territory with the surgical area. The interscalene block is the approach most commonly used for shoulder surgery. Supraclavicular, infraclavicular, and axillary blocks are indicated for elbow and forearm surgery. Puncture techniques have evolved dramatically with ultrasound guidance. Instead of targeting the nerves directly, it is now recommended to look for diffusion areas. Typically, local anesthetics are deposited around vessels, often as a single injection. Phrenic nerve block can occur with the interscalene and supraclavicular approaches. Ulnar nerve blockade is almost never achieved with the interscalene approach and not always present with a supraclavicular block. If ultrasound guidance is used, the risk for pneumothorax with a supraclavicular approach is reduced significantly. Nerve damage and vascular puncture are possible with all approaches. If an axillary approach is chosen, the consequences of vascular puncture can be minimized because this site is compressible. CONCLUSIONS: Upper limb regional anesthesia has gained in popularity because of its effectiveness and the safety profile associated with ultrasound-guided techniques.

Complications of single-injection ultrasound-guided infraclavicular block: a cohort study.

INTRODUCTION: In recent studies on ultrasound-guided infraclavicular block (ICB), the authors have favoured a single injection posterior to the axillary artery rather than multiple injections; however, procedural complications and success rates associated with single-injection ultrasound-guided ICB are not well known. We undertook an observational study to evaluate the success rates of experienced and non-experienced operators performing ICBs and to identify the complications associated with ultrasound-guided single-injection ICB. METHODS: We conducted an observational cohort study of all ultrasound-guided single-injection ICBs performed over a two-year period (2008-2010). We identified the subjects for our study using a local database and excluded patients younger than 18 yr and those who received a continuous ICB. Complications (non-neurological and neurological) and ICB success rates were the primary and secondary end points, respectively. We collected the following data from patients' charts: patient demographics, types of complications and their respective frequencies, and the experience of the clinician performing the ICBs, and we identified potential late complications by telephone interview. Using a seven-point Likert scale, two experts in regional anesthesia evaluated the likelihood of a relationship between the identified neurological signs or symptoms and the ICB. A neurologist then evaluated the complications identified as being potentially related to the ICB. Summary data were collated, and 95% confidence intervals (CI) were calculated. RESULTS: We reviewed 627 ICB procedures, and 496 (79%) patients received telephone interviews. Most patients were males who had undergone either plastic or orthopedic surgery. Mepivacaine 1.5% was used in 96% of cases with a median volume of 30 mL [interquartile range 30-38]. We identified 131 cases of neurological signs or symptoms. Four cases were retained as possible links to the ICB, but they underwent complete resolution of symptoms at the time of evaluation. Two possible cases of local anesthetic toxicity were observed. There was a 93% success rate (95% CI 91 to 95) and the results were comparable between the experienced and the non-experienced operators (94% vs 93%, respectively). DISCUSSION: We observed few complications associated with a single-injection ultrasound-guided ICB and a high success rate regardless of the operator's expertise. The technique appears to be reliable, easy to perform, and safe.

Phenotyping the Responses to Systemic Corticosteroids in the Management of Asthma Attacks (PRISMA): protocol for an observational and translational pilot study.

INTRODUCTION: Asthma and its associated exacerbation are heterogeneous. Although severe asthma attacks are systematically prescribed corticosteroids and often antibiotics, little is known about the variability of response to these therapies. Blood eosinophils and fractional exhaled nitric oxide (FeNO) are type 2 inflammation biomarkers that have established mechanistic, prognostic and theragnostic values in chronic asthma, but their utility in acute asthma is unclear. We speculate that the clinical and biological response to those treatments varies according to inflammometry and microbiological test results. METHODS AND ANALYSIS: An observational longitudinal pilot study with multimodal clinical and translational assessments will be performed on 50 physician-diagnosed ≥12-year-old asthmatics presenting with an asthma attack and 12 healthy controls, including blood eosinophil count (venous and point-of-care (POC) capillary blood), FeNO and testing for airway infection (sputum cultures and POC nasopharyngeal swabs). People with asthma will be assessed on day 0 and after a 7-day corticosteroid course, with home monitoring performed in between. The primary analysis will be the change in the forced expiratory volume in 1 s according to type 2 inflammatory status (blood eosinophils ≥0.15×109/L and/or FeNO ≥25 ppb) after treatment. Key secondary analyses will compare changes in symptom scores and the proportion of patients achieving a minimal clinically important difference. Exploratory analyses will assess the relationship between clinical, lung function, inflammatory and microbiome parameters; satisfaction plus reliability indices of POC tests; and sex-gender variability in treatment response. Ultimately, this pilot study will serve to plan a larger trial comparing the clinical and biological response to systemic corticosteroids according to inflammatory biomarkers, offering valuable guidance for more personalised therapeutic strategies in asthma attacks. ETHICS AND DISSEMINATION: The protocol has been approved by the Research Ethics Committee of the CIUSSS de l'Estrie-CHUS, Sherbrooke, Quebec, Canada (#2023-4687). Results will be communicated in an international meeting and submitted to a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT05870215).

Viruses - a major cause of amyloid deposition in the brain.

INTRODUCTION: Clinically, Alzheimer's disease (AD) is a syndrome with a spectrum of various cognitive disorders. There is a complete dissociation between the pathology and the clinical presentation. Therefore, we need a disruptive new approach to be able to prevent and treat AD. AREAS COVERED: In this review, the authors extensively discuss the evidence why the amyloid beta is not the pathological cause of AD which makes therefore the amyloid hypothesis not sustainable anymore. They review the experimental evidence underlying the role of microbes, especially that of viruses, as a trigger/cause for the production of amyloid beta leading to the establishment of a chronic neuroinflammation as the mediator manifesting decades later by AD as a clinical spectrum. In this context, the emergence and consequences of the infection/antimicrobial protection hypothesis are described. The epidemiological and clinical data supporting this hypothesis are also analyzed. EXPERT OPINION: For decades, we have known that viruses are involved in the pathogenesis of AD. This discovery was ignored and discarded for a long time. Now we should accept this fact, which is not a hypothesis anymore, and stimulate the research community to come up with new ideas, new treatments, and new concepts.