Helmet noninvasive ventilation compared to facemask noninvasive ventilation and high-flow nasal cannula in acute respiratory failure: a systematic review and meta-analysis.

BACKGROUND: Although small randomised controlled trials (RCTs) and observational studies have examined helmet noninvasive ventilation (NIV), uncertainty remains regarding its role. We conducted a systematic review and meta-analysis to examine the effect of helmet NIV compared to facemask NIV or high-flow nasal cannula (HFNC) in acute respiratory failure. METHODS: We searched multiple databases to identify RCTs and observational studies reporting on at least one of mortality, intubation, intensive care unit (ICU) length of stay, NIV duration, complications or comfort with NIV therapy. We assessed study risk of bias using the Cochrane Risk of Bias 2 tool for RCTs and the Ottawa-Newcastle Scale for observational studies, and rated certainty of pooled evidence using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) framework. RESULTS: We separately pooled data from 16 RCTs (n=949) and eight observational studies (n=396). Compared to facemask NIV, based on low certainty of evidence, helmet NIV may reduce mortality (relative risk 0.56, 95% CI 0.33-0.95) and intubation (relative risk 0.35, 95% CI 0.22-0.56) in both hypoxic and hypercapnic respiratory failure, but may have no effect on duration of NIV. There was an uncertain effect of helmet NIV on ICU length of stay and development of pressure sores. Data from observational studies were consistent with the foregoing findings but of lower certainty. Based on low and very low certainty data, helmet NIV may reduce intubation compared to HFNC, but its effect on mortality is uncertain. CONCLUSIONS: Compared to facemask NIV, helmet NIV may reduce mortality and intubation; however, the effect of helmet NIV compared to HFNC remains uncertain.

Blood Culture Results Before and After Antimicrobial Administration in Patients With Severe Manifestations of Sepsis: A Diagnostic Study.

Background: Administering antimicrobial agents before obtaining blood cultures could potentially decrease time to treatment and improve outcomes, but it is unclear how this strategy affects diagnostic sensitivity. Objective: To determine the sensitivity of blood cultures obtained shortly after initiation of antimicrobial therapy in patients with severe manifestations of sepsis. Design: Patient-level, single-group, diagnostic study. (ClinicalTrials.gov: NCT01867905). Setting: 7 emergency departments in North America. Participants: Adults with severe manifestations of sepsis, including systolic blood pressure less than 90 mm Hg or a serum lactate level of 4 mmol/L or more. Intervention: Blood cultures were obtained before and within 120 minutes after initiation of antimicrobial treatment. Measurements: Sensitivity of blood cultures obtained after initiation of antimicrobial therapy. Results: Of 3164 participants screened, 325 were included in the study (mean age, 65.6 years; 62.8% men) and had repeated blood cultures drawn after initiation of antimicrobial therapy (median time, 70 minutes [interquartile range, 50 to 110 minutes]). Preantimicrobial blood cultures were positive for 1 or more microbial pathogens in 102 of 325 (31.4%) patients. Postantimicrobial blood cultures were positive for 1 or more microbial pathogens in 63 of 325 (19.4%) patients. The absolute difference in the proportion of positive blood cultures between pre- and postantimicrobial testing was 12.0% (95% CI, 5.4% to 18.6%; P < 0.001). Sensitivity of postantimicrobial culture was 52.9% (CI, 42.8% to 62.9%). When the results of other microbiological cultures were included, microbial pathogens were found in 69 of 102 (67.6% [CI, 57.7% to 76.6%]) patients. Limitation: Only a proportion of screened patients were recruited. Conclusion: Among patients with severe manifestations of sepsis, initiation of empirical antimicrobial therapy significantly reduces the sensitivity of blood cultures drawn shortly after treatment initiation. Primary Funding Source: Vancouver Coastal Health, St. Paul's Hospital Foundation Emergency Department Support Fund, the Fonds de recherche Santé-Québec, and the Maricopa Medical Foundation.

A Case of Pericarditis and Pericardial Masses Associated With Mycobacterium Paragordonae.

Tuberculosis is a common cause of pericarditis worldwide and has been associated with pericardial masses. Non-tuberculous mycobacteria are uncommonly associated with cardiac disease, having primarily been described in cases of endocarditis. Here we describe a case of an immunocompetent patient with Mycobacterium paragordonae infection causing pericarditis with a large effusion containing pericardial masses. The patient presented with chest pain, hypoxia and biochemical evidence of inflammation (CRP 216.1 mg/L). This report illustrates a rare case of pericarditis with pericardial masses associated with non-tuberculous mycobacteria and the first example of pericarditis associated with M. paragordonae.

New-Onset Atrial Fibrillation After Transcatheter Aortic Valve Replacement: A Systematic Review and Meta-Analysis.

OBJECTIVES: The authors aimed to identify risk factors and outcomes associated with new-onset atrial fibrillation (NOAF) after transcatheter aortic valve replacement (TAVR). BACKGROUND: NOAF is a common complication after TAVR, although estimates of the precise occurrence are variable. This study sought to quantify the occurrence of NOAF after TAVR and to explore the outcomes and predictors associated with this complication. METHODS: We searched Medline, EMBASE, and the Cochrane database from 2016 to 2020 for articles that reported NOAF after TAVR. We extracted data for studies published before 2016 from a previous systematic review. We pooled data using a random effects model. RESULTS: We identified 179 studies with 241,712 total participants (55,271 participants with pre-existing atrial fibrillation (AF) were excluded) that reported NOAF from 2008 to 2020. The pooled occurrence of NOAF after TAVR was 9.9% (95% CI: 8.1%-12%). NOAF after TAVR was associated with a longer index hospitalization (mean difference = 2.66 days; 95% CI: 1.05-4.27), a higher risk of stroke in the first 30 days (risk ratio [RR]: 2.35; 95% CI: 2.12-2.61), 30-day mortality (RR: 1.76; 95% CI: 1.12-2.76), major or life-threatening bleeding (RR: 1.60; 95% CI: 1.39-1.84), and permanent pacemaker implantation (RR: 1.12; 95% CI: 1.05-1.18). Risk factors for the development of NOAF after TAVR included higher Society of Thoracic Surgeons score, transapical access, pulmonary hypertension, chronic kidney disease, peripheral vascular disease, and severe mitral regurgitation, suggesting that the risk for NOAF is highest in more comorbid TAVR patients. CONCLUSIONS: NOAF is common after TAVR. Whether AF after TAVR is a causal factor or a marker of sicker patients remains unclear.

The Usefulness of the Rapid Shallow Breathing Index in Predicting Successful Extubation: A Systematic Review and Meta-analysis.

BACKGROUND: Clinicians use several measures to ascertain whether individual patients will tolerate liberation from mechanical ventilation, including the rapid shallow breathing index (RSBI). RESEARCH QUESTION: Given varied use of different thresholds, patient populations, and measurement characteristics, how well does RSBI predict successful extubation? STUDY DESIGN AND METHODS: We searched six databases from inception through September 2019 and selected studies reporting the accuracy of RSBI in the prediction of successful extubation. We extracted study data and assessed quality independently and in duplicate. RESULTS: We included 48 studies involving RSBI measurements of 10,946 patients. Pooled sensitivity for RSBI of < 105 in predicting extubation success was moderate (0.83 [95% CI, 0.78-0.87], moderate certainty), whereas specificity was poor (0.58 [95% CI, 0.49-0.66], moderate certainty) with diagnostic ORs (DORs) of 5.91 (95% CI, 4.09-8.52). RSBI thresholds of < 80 or 80 to 105 yielded similar sensitivity, specificity, and DOR. These findings were consistent across multiple subgroup analyses reflecting different patient characteristics and operational differences in RSBI measurement. INTERPRETATION: As a stand-alone test, the RSBI has moderate sensitivity and poor specificity for predicting extubation success. Future research should evaluate its role as a permissive criterion to undergo a spontaneous breathing trial (SBT) for patients who are at intermediate pretest probability of passing an SBT. TRIAL REGISTRY: PROSPERO; No.: CRD42020149196; URL: www.crd.york.ac.uk/prospero/.

qSOFA does not predict bacteremia in patients with severe manifestations of sepsis.

BACKGROUND: Bloodstream infections in septic patients may be missed due to preceding antibiotic therapy prior to obtaining blood cultures. We leveraged the FABLED cohort study to determine if the quick Sequential Organ Failure Assessment (qSOFA) score could reliably identify patients at higher risk of bacteremia in patients who may have false negative blood cultures due to previously administered antibiotic therapy. METHODS: We conducted a multi-centre diagnostic study among adult patients with severe manifestations of sepsis. Patients were enrolled in one of seven participating centres between November 2013 and September 2018. All patients from the FABLED cohort had two sets of blood cultures drawn prior to the administration of antimicrobial therapy, as well as additional blood cultures within 4 hours of treatment initiation. Participants were categorized according to qSOFA score, with a score ≥2 being considered positive. RESULTS: Among 325 patients with severe manifestations of sepsis, a positive qSOFA score (defined as a score ≥2) on admission was 58% sensitive (95% CI 48% to 67%) and 41% specific (95% CI 34% to 48%) for predicting bacteremia. Among patients with negative post-antimicrobial blood cultures, a positive qSOFA score was 57% sensitive (95% CI 42% to 70%) and 42% specific (95% CI 35% to 49%) to detect patients who were originally bacteremic prior to the initiation of therapy. CONCLUSIONS: Our results suggest that the qSOFA score cannot be used to identify patients at risk for occult bacteremia due to the administration of antibiotics pre-blood culture.

HISTORIQUE: Les infections sanguines peuvent rester non diagnostiquées chez les patients septiques avant l'obtention des cultures sanguines, en raison d'une antibiothérapie antérieure. Les chercheurs ont puisé dans l'étude de cohorte FABLED pour déterminer si le score rapide de l'évaluation séquentielle d'insuffisance des organes (Sequential Organ Failure Assessment, qSOFA) pourrait dépister les patients à plus haut risque de bactériémie avec fiabilité, malgré la possibilité de cultures sanguines faussement négatives en raison d'une antibiothérapie antérieure. MÉTHODOLOGIE: Les chercheurs ont réalisé une étude diagnostique multicentrique chez des patients adultes ayant de graves manifestations de sepsis. Les patients ont été inscrits dans l'un des sept centres participants entre novembre 2013 et septembre 2018. Tous les patients de l'étude de cohorte FABLED avaient subi deux séries de cultures sanguines avant de recevoir une thérapie antimicrobienne, de même qu'une autre série de cultures sanguines dans les quatre heures suivant le début du traitement. Les participants ont été classés en fonction de leur score de qSOFA, un score d'au moins 2 étant considéré comme positif. RÉSULTATS: Chez les 325 patients ayant de graves manifestations de sepsis, un score de qSOFA positif (défini comme un score d'au moins 2) à l'admission était sensible à 58 % (IC à 95 %, 48 % à 67 %) et spécifique à 41 % (IC à 95 %, 34 % à 48 %) pour prédire la bactériémie. Chez les patients dont les cultures sanguines étaient négatives après la prise d'antimicrobiens, un score de qSOFA positif était sensible à 57 % (IC à 95 %, 42 % à 70 %) et spécifique à 42 % (IC à 95 %, 35 % à 49 %) pour dépister les patients atteints d'une bactériémie avant le début du traitement. CONCLUSIONS: Selon les résultats, le score de qSOFA ne peut pas être utilisé pour dépister les patients à risque de bactériémie occulte à cause de l'administration d'antibiotiques avant la culture sanguine.

Neither Blood Culture Positivity nor Time to Positivity Is Associated With Mortality Among Patients Presenting With Severe Manifestations of Sepsis: The FABLED Cohort Study.

BACKGROUND: Sepsis is a leading cause of morbidity, mortality, and health care costs worldwide. METHODS: We conducted a multicenter, prospective cohort study evaluating the yield of blood cultures drawn before and after empiric antimicrobial administration among adults presenting to the emergency department with severe manifestations of sepsis. Enrolled patients who had the requisite blood cultures drawn were followed for 90 days. We explored the independent association between blood culture positivity and its time to positivity in relation to 90-day mortality. RESULTS: Three hundred twenty-five participants were enrolled; 90-day mortality among the 315 subjects followed up was 25.4% (80/315). Mortality was associated with age (mean age [standard deviation] in those who died was 72.5 [15.8] compared with 62.9 [17.7] years among survivors; P < .0001), greater Charlson Comorbidity Index (2 [interquartile range {IQR}, 1-3] vs 1 [IQR, 0-3]; P = .008), dementia (13/80 [16.2%] vs 18/235 [7.7%]; P = .03), cancer (27/80 [33.8%] vs 47/235 [20.0%]; P = .015), positive quick Sequential Organ Failure Assessment score (57/80 [71.2%] vs 129/235 [54.9%]; P = .009), and normal white blood cell count (25/80 [31.2%] vs 42/235 [17.9%]; P = .02). The presence of bacteremia, persistent bacteremia after antimicrobial infusion, and shorter time to blood culture positivity were not associated with mortality. Neither the source of infection nor pathogen affected mortality. CONCLUSIONS: Although severe sepsis is an inflammatory condition triggered by infection, its 90-day survival is not influenced by blood culture positivity nor its time to positivity. CLINICAL TRIALS REGISTRATION: NCT01867905.

Real-world Time to Positivity of 2 Widely Used Commercial Blood Culture Systems in Patients With Severe Manifestations of Sepsis: An Analysis of the FABLED Study.

BACKGROUND: Of all microbiological tests performed, blood cultures have the most impact on patient care. Timely results are essential, especially in the management of sepsis. While there are multiple available blood culture systems on the market, they have never been compared in a prospective study in a critically ill population. METHODS: We performed an analysis of the FABLED study cohort to compare culture results and time to positivity (TTP) of 2 widely used blood culture systems: BacT/Alert and BACTEC. In this multisite prospective study, patients with severe manifestations of sepsis had cultures drawn before antibiotics using systematic enrollment criteria and blood drawing methodology allowing for minimization of pre-analytical biases. RESULTS: We enrolled 315 patients; 144 had blood cultures (47 positive) with BacT/Alert and 171 with BACTEC (53 positive). Patients whose blood cultures were processed using the BacT/Alert system were younger (median, 64 vs 70 years; P = .003), had a higher proportion of HIV (9.03% vs 1.75%; P = .008) and a lower qSOFA (P = .003). There were no statistically significant differences in the most commonly identified bacterial species. TTP was shorter for BACTEC (median [interquartile range {IQR}], 12.5 [10-14] hours) compared with BacT/Alert (median [IQR], 17 [14-21] hours; P < .0001). CONCLUSIONS: In this large prospective multi-centre study comparing the two blood culture systems among patients with severe manifestations of sepsis, and using a rigorous pre-analytical methodology, the BACTEC system yielded positive culture results 4.5 hours earlier than BacT/Alert. These results apply to commonly isolated bacteria. However, our study design did not allow direct comparison of TTP for unusual pathogens nor of clinical sensitivity between systems. More research is needed to determine the clinical implications of this finding.