Antipsychotics in the Treatment of Delirium in Critically Ill Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

OBJECTIVES: To conduct a systematic review and meta-analysis assessing whether the use of antipsychotic medications in critically ill adult patients with delirium impacts patient-important outcomes. DATA SOURCES: A medical librarian searched Ovid MEDLINE, EMBASE, APA PsycInfo, and Wiley's Cochrane Library as well as clinicaltrials.gov and the World Health Organization International Clinical Trials Registry Platform up to November 2023. STUDY SELECTION: Independently and in duplicate, reviewers screened abstracts and titles for eligibility, then full text of qualifying studies. We included parallel-group randomized controlled trials (RCTs) that included critically ill adult patients with delirium. The intervention group was required to receive antipsychotic medications at any dose, whereas the control group received usual care or placebo. DATA EXTRACTION: Reviewers extracted data independently and in duplicate using a piloted abstraction form. Statistical analyses were conducted using RevMan software (version 5.4). DATA SYNTHESIS: Five RCTs ( n = 1750) met eligibility criteria. The use of antipsychotic medications compared with placebo did not increase the number of delirium- or coma-free days (mean difference 0.90 d; 95% CI, -0.32 to 2.12; moderate certainty), nor did it result in a difference in mortality, duration of mechanical ventilation, ICU, or hospital length of stay. The use of antipsychotics did not result in an increased risk of adverse events (risk ratio 1.27; 95% CI, 0.71-2.30; high certainty). Subgroup analysis of typical versus atypical antipsychotics did not identify any subgroup effect for any outcome. CONCLUSIONS: In conclusion, our systematic review and meta-analysis demonstrated with moderate certainty that there is no difference in delirium- or coma-free days when delirious critically ill adults are treated with antipsychotic medications. Further studies in the subset of patients with hyperactive delirium may be of benefit.

Comparative effectiveness of alternative spontaneous breathing trial techniques: a systematic review and network meta-analysis of randomized trials.

BACKGROUND: The spontaneous breathing trial (SBT) technique that best balance successful extubation with the risk for reintubation is unknown. We sought to determine the comparative efficacy and safety of alternative SBT techniques. METHODS: We searched Medline, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to February 2023 for randomized or quasi-randomized trials comparing SBT techniques in critically ill adults and children and reported initial SBT success, successful extubation, reintubation (primary outcomes) and mortality (ICU, hospital, most protracted; secondary outcome) rates. Two reviewers screened, reviewed full-texts, and abstracted data. We performed frequentist random-effects network meta-analysis. RESULTS: We included 40 RCTs (6716 patients). Pressure Support (PS) versus T-piece SBTs was the most common comparison. Initial successful SBT rates were increased with PS [risk ratio (RR) 1.08, 95% confidence interval (CI) (1.05-1.11)], PS/automatic tube compensation (ATC) [1.12 (1.01 -1.25), high flow nasal cannulae (HFNC) [1.07 (1.00-1.13) (all moderate certainty), and ATC [RR 1.11, (1.03-1.20); low certainty] SBTs compared to T-piece SBTs. Similarly, initial successful SBT rates were increased with PS, ATC, and PS/ATC SBTs compared to continuous positive airway pressure (CPAP) SBTs. Successful extubation rates were increased with PS [RR 1.06, (1.03-1.09); high certainty], ATC [RR 1.13, (1.05-1.21); moderate certainty], and HFNC [RR 1.06, (1.02-1.11); high certainty] SBTs, compared to T-piece SBTs. There was little to no difference in reintubation rates with PS (vs. T-piece) SBTs [RR 1.05, (0.91-1.21); low certainty], but increased reintubation rates with PS [RR 2.84, (1.61-5.03); moderate certainty] and ATC [RR 2.95 (1.57-5.56); moderate certainty] SBTs compared to HFNC SBTs. CONCLUSIONS: SBTs conducted with pressure augmentation (PS, ATC, PS/ATC) versus without (T-piece, CPAP) increased initial successful SBT and successful extubation rates. Although SBTs conducted with PS or ATC versus HFNC increased reintubation rates, this was not the case for PS versus T-piece SBTs.

Venous congestion in septic shock quantified with point-of-care ultrasound: a pilot prospective multicentre cohort study.

PURPOSE: Venous congestion is a pathophysiologic state that can result in organ dysfunction, particularly acute kidney injury (AKI). We sought to evaluate the feasibility of performing a definitive observational study to determine the impact of venous congestion quantified using point-of-care ultrasound (POCUS) in patients with septic shock. METHODS: We conducted a prospective observational feasibility study at two intensive care units (ICUs). We recruited adult patients with septic shock within 12 hr of ICU admission. Using the validated Venous Excess Ultrasound Score (VEXUS), we quantified venous congestion on day 1 and day 3 of ICU admission. The primary feasibility outcome was successful completion rate of the two VEXUS scores. We performed a survival analysis to quantify the hazard of renal replacement therapy (RRT). RESULTS: We enrolled 75 patients from January 2022 to January 2023. The success rate of completion for VEXUS scans was 94.5% (95% confidence interval [CI], 89.5 to 97.6). Severe venous congestion was present in 19% (14/75) of patients on ICU admission day 1 and in 16% (10/61) of patients on day 3. Venous congestion on ICU admission may be associated with a higher risk of requiring RRT (unadjusted hazard ratio, 3.35; 95% CI, 0.94 to 11.88; P = 0.06). CONCLUSIONS: It is feasible to conduct a definitive observational study exploring the association between venous congestion quantified with POCUS and clinical outcomes in patients with septic shock. We hypothesize that venous congestion may be associated with an increased hazard of receiving RRT.

RéSUMé: OBJECTIF: La congestion veineuse est un état physiopathologique qui peut entraîner un dysfonctionnement des organes, en particulier une insuffisance rénale aiguë (IRA). Nous avons cherché à évaluer la faisabilité de la réalisation d'une étude observationnelle définitive pour déterminer l'impact de la congestion veineuse quantifiée à l'aide de l'échographie ciblée (POCUS) chez des patient·es en choc septique. MéTHODE: Nous avons réalisé une étude de faisabilité observationnelle prospective dans deux unités de soins intensifs (USI). Nous avons recruté des patient·es adultes souffrant d'un choc septique dans les 12 heures suivant leur admission aux soins intensifs. À l'aide du score VEXUS (score d'échographie de l'excès veineux) validé, nous avons quantifié la congestion veineuse au jour 1 et au jour 3 de leur admission aux soins intensifs. Le principal critère de faisabilité était le taux de réussite des deux scores VEXUS. Nous avons réalisé une analyse de survie pour quantifier le risque de thérapie de substitution rénale (TSR). RéSULTATS: Nous avons recruté 75 patient·es de janvier 2022 à janvier 2023. Le taux de réussite des scores VEXUS était de 94,5 % (intervalle de confiance [IC] à 95 %, 89,5 à 97,6). Une congestion veineuse sévère était présente chez 19 % (14/75) des patient·es au jour 1 d'admission aux soins intensifs et chez 16 % (10/61) des patient·es au jour 3. La congestion veineuse lors de l'admission aux soins intensifs peut être associée à un risque plus élevé de nécessiter une TSR (rapport de risque non ajusté, 3,35; IC 95 %, 0,94 à 11,88; P = 0,06). CONCLUSION: Il est possible de mener une étude observationnelle définitive explorant l'association entre la congestion veineuse quantifiée par POCUS et les devenirs cliniques chez les patient·es en choc septique. Nous émettons l'hypothèse que la congestion veineuse peut être associée à un risque accru de recevoir une thérapie de substitution rénale.

Nonsteroidal anti-inflammatory drugs for analgesia in intensive care units: a survey of Canadian critical care physicians.

PURPOSE: Opioids remain the mainstay of analgesia for critically ill patients, but its exposure is associated with negative effects including persistent use after discharge. Nonsteroidal anti-inflammatory drugs (NSAIDs) may be an effective alternative to opioids with fewer adverse effects. We aimed to describe beliefs and attitudes towards the use of NSAIDs in adult intensive care units (ICUs). METHODS: Our survey of Canadian ICU physicians was conducted using a web-based platform and distributed through the Canadian Critical Care Society (CCCS) email distribution list. We used previously described survey development methodology including question generation and reduction, pretesting, and clinical sensibility and pilot testing. RESULTS: We received 115 completed surveys from 321 CCCS members (36%). Nonsteroidal anti-inflammatory drugs use was most described as "rarely" (59 respondents, 51%) with the primary concern being adverse events (acute kidney injury [108 respondents, 94%] and gastrointestinal bleeding [92 respondents, 80%]). The primary preferred analgesic was acetaminophen (75 respondents, 65%) followed by opioids (40 respondents, 35%). Most respondents (91 respondents, 80%) would be willing to participate in a randomized controlled trial examining NSAID use in critical care. CONCLUSIONS: In our survey, Canadian critical care physicians did not mention commonly using NSAIDs primarily because of concerns about adverse events. Nevertheless, respondents were interested in further studying ketorolac, a commonly used NSAID outside of the ICU, in critically ill patients.

RéSUMé: OBJECTIF: Les opioïdes restent le pilier de l'analgésie pour les patient·es gravement malades, mais l'exposition à ces agents est associée à des effets négatifs, notamment à leur utilisation persistante après le congé de l'hôpital. Les anti-inflammatoires non stéroïdiens (AINS) pourraient constituer une alternative efficace aux opioïdes avec moins d'effets indésirables. Nous avons cherché à décrire les croyances et les attitudes à l'égard de l'utilisation des AINS dans les unités de soins intensifs (USI) pour adultes. MéTHODE: Notre sondage auprès des médecins intensivistes au Canada a été mené à l'aide d'une plateforme Web et distribué aux personnes sur la liste de distribution électronique de la Société canadienne de soins intensifs (SCSI). Nous avons utilisé une méthodologie d'élaboration d'enquêtes décrite précédemment, y compris la génération et la réduction de questions, les tests préalables, la sensibilité clinique et les tests pilotes. RéSULTATS: Nous avons reçu 115 sondages remplis par 321 membres de la SCSI (36 %). L'utilisation d'anti-inflammatoires non stéroïdiens a été décrite comme « rare ¼ (59 répondant·es, 51 %), la principale préoccupation étant les événements indésirables (insuffisance rénale aiguë [108 répondant·es, 94 %] et saignements gastro-intestinaux [92 répondant·es, 80 %]). Le principal analgésique préféré était l'acétaminophène (75 répondant·es, 65 %), suivi des opioïdes (40 répondant·es, 35 %). La plupart des répondant·es (91 répondant·es, 80 %) seraient prêt·es à participer à une étude randomisée contrôlée examinant l'utilisation des AINS en soins intensifs. CONCLUSION: Dans notre sondage, les médecins intensivistes au Canada n'ont pas mentionné l'utilisation courante d'AINS, principalement en raison de préoccupations concernant leurs effets indésirables. Néanmoins, les répondant·es étaient intéressé·es à étudier plus avant le kétorolac, un AINS couramment utilisé en dehors des soins intensifs, chez les patient·es gravement malades.

Mean Arterial Pressure Targets and Patient-Important Outcomes in Critically Ill Adults: A Systematic Review and Meta-Analysis of Randomized Trials.

OBJECTIVE: To conduct a systematic review and meta-analysis to determine whether targeting a higher mean arterial pressure (MAP) compared with a lower MAP in adults with shock results in differences in patient important outcomes. DATA SOURCES: We searched MEDLINE, EMBASE, the Cochrane Library, and ClinicalTrials.gov through May 2021. STUDY SELECTION: Titles and abstracts were screened independently and in duplicate to identify potentially eligible studies, then full text for final eligibility. We included parallel-group randomized controlled trials in adult patients with a diagnosis of shock requiring vasoactive medications. The higher MAP group was required to receive vasoactive medications to target a higher MAP as established by study authors, whereas the lower MAP group received vasoactive medications to target lower MAP. DATA EXTRACTION: In triplicate, reviewers independently extracted data using a prepiloted abstraction form. Statistical analyses were conducted using the RevMan software Version 5.3. DATA SYNTHESIS: Six randomized controlled trials (n = 3,690) met eligibility criteria. Targeting a higher MAP (75-85 mm Hg) compared with lower MAP of 65 mm Hg resulted in no difference in mortality (relative risk [RR], 1.06; 95% CI, 0.98-1.15; I2 = 0%; p = 0.12; moderate certainty. Targeting a higher MAP resulted in no difference in the risk of undergoing renal replacement therapy (RR, 0.96; 95% CI, 0.83-1.11; I2 = 24%; p = 0.57; moderate certainty); however, a subgroup analysis comparing patients with and without chronic hypertension demonstrated that a higher MAP may reduce the risk of undergoing renal replacement therapy (RR, 0.83; 95% CI, 0.71-0.98; I2 = 0%; p = 0.02). CONCLUSIONS: In conclusion, our systematic review and meta-analysis demonstrated with moderate certainty that there is no difference in mortality when a higher MAP is targeted in critically ill adult patients with shock. Further studies are needed to determine the impact of mean arterial pressure on need for renal replacement therapy in this population.

Nonmotile Subpopulations of Pseudomonas aeruginosa Repress Flagellar Motility in Motile Cells through a Type IV Pilus- and Pel-Dependent Mechanism.

The downregulation of Pseudomonas aeruginosa flagellar motility is a key event in biofilm formation, host colonization, and the formation of microbial communities, but the external factors that repress motility are not well understood. Here, we report that on soft agar, swarming motility can be repressed by cells that are nonmotile due to the absence of a flagellum or flagellar rotation. Mutants that lack either flagellum biosynthesis or rotation, when present at as little as 5% of the total population, suppressed swarming of wild-type cells. Non-swarming cells required functional type IV pili and the ability to produce Pel exopolysaccharide to suppress swarming by the flagellated wild type. Flagellated cells required only type IV pili, but not Pel production, for their swarming to be repressed by non-flagellated cells. We hypothesize that interactions between motile and nonmotile cells may enhance the formation of sessile communities, including those involving multiple genotypes, phenotypically diverse cells, and perhaps other species. IMPORTANCE Our study shows that, under the conditions tested, a small population of non-swarming cells can impact the motility behavior of a larger population. The interactions that lead to the suppression of swarming motility require type IV pili and a secreted polysaccharide, two factors with known roles in biofilm formation. These data suggest that interactions between motile and nonmotile cells may enhance the transition to sessile growth in populations and promote interactions between cells with different genotypes.

Effect of Awake Prone Positioning on Endotracheal Intubation in Patients With COVID-19 and Acute Respiratory Failure: A Randomized Clinical Trial.

Importance: The efficacy and safety of prone positioning is unclear in nonintubated patients with acute hypoxemia and COVID-19. Objective: To evaluate the efficacy and adverse events of prone positioning in nonintubated adult patients with acute hypoxemia and COVID-19. Design, Setting, and Participants: Pragmatic, unblinded randomized clinical trial conducted at 21 hospitals in Canada, Kuwait, Saudi Arabia, and the US. Eligible adult patients with COVID-19 were not intubated and required oxygen (≥40%) or noninvasive ventilation. A total of 400 patients were enrolled between May 19, 2020, and May 18, 2021, and final follow-up was completed in July 2021. Intervention: Patients were randomized to awake prone positioning (n = 205) or usual care without prone positioning (control; n = 195). Main Outcomes and Measures: The primary outcome was endotracheal intubation within 30 days of randomization. The secondary outcomes included mortality at 60 days, days free from invasive mechanical ventilation or noninvasive ventilation at 30 days, days free from the intensive care unit or hospital at 60 days, adverse events, and serious adverse events. Results: Among the 400 patients who were randomized (mean age, 57.6 years [SD, 12.83 years]; 117 [29.3%] were women), all (100%) completed the trial. In the first 4 days after randomization, the median duration of prone positioning was 4.8 h/d (IQR, 1.8 to 8.0 h/d) in the awake prone positioning group vs 0 h/d (IQR, 0 to 0 h/d) in the control group. By day 30, 70 of 205 patients (34.1%) in the prone positioning group were intubated vs 79 of 195 patients (40.5%) in the control group (hazard ratio, 0.81 [95% CI, 0.59 to 1.12], P = .20; absolute difference, -6.37% [95% CI, -15.83% to 3.10%]). Prone positioning did not significantly reduce mortality at 60 days (hazard ratio, 0.93 [95% CI, 0.62 to 1.40], P = .54; absolute difference, -1.15% [95% CI, -9.40% to 7.10%]) and had no significant effect on days free from invasive mechanical ventilation or noninvasive ventilation at 30 days or on days free from the intensive care unit or hospital at 60 days. There were no serious adverse events in either group. In the awake prone positioning group, 21 patients (10%) experienced adverse events and the most frequently reported were musculoskeletal pain or discomfort from prone positioning (13 of 205 patients [6.34%]) and desaturation (2 of 205 patients [0.98%]). There were no reported adverse events in the control group. Conclusions and Relevance: In patients with acute hypoxemic respiratory failure from COVID-19, prone positioning, compared with usual care without prone positioning, did not significantly reduce endotracheal intubation at 30 days. However, the effect size for the primary study outcome was imprecise and does not exclude a clinically important benefit. Trial Registration: ClinicalTrials.gov Identifier: NCT04350723.

Surviving Sepsis Campaign Guidelines on the Management of Adults With Coronavirus Disease 2019 (COVID-19) in the ICU: First Update.

BACKGROUND: The coronavirus disease 2019 pandemic continues to affect millions worldwide. Given the rapidly growing evidence base, we implemented a living guideline model to provide guidance on the management of patients with severe or critical coronavirus disease 2019 in the ICU. METHODS: The Surviving Sepsis Campaign Coronavirus Disease 2019 panel has expanded to include 43 experts from 14 countries; all panel members completed an electronic conflict-of-interest disclosure form. In this update, the panel addressed nine questions relevant to managing severe or critical coronavirus disease 2019 in the ICU. We used the World Health Organization's definition of severe and critical coronavirus disease 2019. The systematic reviews team searched the literature for relevant evidence, aiming to identify systematic reviews and clinical trials. When appropriate, we performed a random-effects meta-analysis to summarize treatment effects. We assessed the quality of the evidence using the Grading of Recommendations, Assessment, Development, and Evaluation approach, then used the evidence-to-decision framework to generate recommendations based on the balance between benefit and harm, resource and cost implications, equity, and feasibility. RESULTS: The Surviving Sepsis Campaign Coronavirus Diease 2019 panel issued nine statements (three new and six updated) related to ICU patients with severe or critical coronavirus disease 2019. For severe or critical coronavirus disease 2019, the panel strongly recommends using systemic corticosteroids and venous thromboprophylaxis but strongly recommends against using hydroxychloroquine. In addition, the panel suggests using dexamethasone (compared with other corticosteroids) and suggests against using convalescent plasma and therapeutic anticoagulation outside clinical trials. The Surviving Sepsis Campaign Coronavirus Diease 2019 panel suggests using remdesivir in nonventilated patients with severe coronavirus disease 2019 and suggests against starting remdesivir in patients with critical coronavirus disease 2019 outside clinical trials. Because of insufficient evidence, the panel did not issue a recommendation on the use of awake prone positioning. CONCLUSION: The Surviving Sepsis Campaign Coronavirus Diease 2019 panel issued several recommendations to guide healthcare professionals caring for adults with critical or severe coronavirus disease 2019 in the ICU. Based on a living guideline model the recommendations will be updated as new evidence becomes available.

The cuff leak test in critically ill patients: An international survey of intensivists.

BACKGROUND: The cuff leak test (CLT) is used to assess laryngeal edema prior to extubation. There is limited evidence for its diagnostic accuracy and conflicting guidelines surrounding its use in critically ill patients who do not have risk factors for laryngeal edema. The primary study aim was to describe intensivists' beliefs, attitudes, and practice regarding the use of the CLT. METHODS: A 13-item survey was developed, pilot-tested, and subjected to clinical sensibility testing. The survey was distributed electronically through MetaClinician®. Descriptive statistics and multivariable regression analysis were performed to examine associations between participant demographics and survey responses. RESULTS: 1184 practicing intensivists from 17 countries in North and South America, Europe, Oceania, and Asia participated. The majority (59%) of respondents reported rarely or never perform the CLT prior to extubating patients not at high risk of laryngeal edema, which correlated with 54% of respondents reporting they believed a failed CLT did not predict reintubation. Intensivists from the Middle East were 2.4 times more likely to request a CLT compared to those from North America. Intensivists with base training in medicine or emergency medicine were more likely to request a CLT prior to extubation compared to those with base training in anesthesiology. CONCLUSION: Use of the CLT prior to extubating patients not at high risk of laryngeal edema in the intensive care unit is highly variable. Practice appears to be influenced by country of practice and base specialty training.

Ethanol Decreases Pseudomonas aeruginosa Flagellar Motility through the Regulation of Flagellar Stators.

Pseudomonas aeruginosa frequently encounters microbes that produce ethanol. Low concentrations of ethanol reduced P. aeruginosa swim zone area by up to 45% in soft agar. The reduction of swimming by ethanol required the flagellar motor proteins MotAB and two PilZ domain proteins (FlgZ and PilZ). PilY1 and the type 4 pilus alignment complex (comprising PilMNOP) were previously implicated in MotAB regulation in surface-associated cells and were required for ethanol-dependent motility repression. As FlgZ requires the second messenger bis-(3'-5')-cyclic dimeric GMP (c-di-GMP) to represses motility, we screened mutants lacking genes involved in c-di-GMP metabolism and found that mutants lacking diguanylate cyclases SadC and GcbA were less responsive to ethanol. The double mutant was resistant to its effects. As published previously, ethanol also represses swarming motility, and the same genes required for ethanol effects on swimming motility were required for its regulation of swarming. Microscopic analysis of single cells in soft agar revealed that ethanol effects on swim zone area correlated with ethanol effects on the portion of cells that paused or stopped during the time interval analyzed. Ethanol increased c-di-GMP in planktonic wild-type cells but not in ΔmotAB or ΔsadC ΔgcbA mutants, suggesting c-di-GMP plays a role in the response to ethanol in planktonic cells. We propose that ethanol produced by other microbes induces a regulated decrease in P. aeruginosa motility, thereby promoting P. aeruginosa colocalization with ethanol-producing microbes. Furthermore, some of the same factors involved in the response to surface contact are involved in the response to ethanol.IMPORTANCE Ethanol is an important biologically active molecule produced by many bacteria and fungi. It has also been identified as a potential marker for disease state in cystic fibrosis. In line with previous data showing that ethanol promotes biofilm formation by Pseudomonas aeruginosa, here we report that ethanol reduces swimming motility using some of the same proteins involved in surface sensing. We propose that these data may provide insight into how microbes, via their metabolic byproducts, can influence P. aeruginosa colocalization in the context of infection and in other polymicrobial settings.

Minimal impact electro-injection of cells undergoing dynamic shape change reveals calpain activation.

The ability of neutrophils to rapidly change shape underlies their physiological functions of phagocytosis and spreading. A major problem in establishing the mechanism is that conventional microinjection of substances and indicators interferes with this dynamic cell behaviour. Here we show that electroinjection, a "no-touch" point-and-shoot means of introducing material into the cell, is sufficiently gentle to allow neutrophils to be injected whilst undergoing chemokinesis and spreading without disturbing cell shape change behaviour. Using this approach, a fluorogenic calpain-1 selective peptide substrate was introduced into the cytosol of individual neutrophils undergoing shape changes. These data showed that (i) physiologically elevated cytosolic Ca(2+) concentrations were sufficient to trigger calpain-1 activation, blockade of Ca(2+) influx preventing calpain activation and (ii) calpain-1 activity was elevated in spreading neutrophil. These findings provide the first direct demonstration of a physiological role for Ca(2+) elevation in calpain-1 activation and rapid cell spreading. Electroinjection of cells undergoing dynamic shape changes thus opens new avenues of investigation for defining the molecular mechanism underlying dynamic cell shape changes.

Spontaneous Breathing Trial Techniques for Extubating Adults and Children Who Are Critically Ill: A Systematic Review and Meta-Analysis.

Importance: Considerable controversy exists regarding the best spontaneous breathing trial (SBT) technique to use. Objective: To summarize trials comparing alternative SBTs. Data Sources: Several databases (MEDLINE [from inception to February 2023], the Cochrane Central Register of Controlled Trials [in February 2023], and Embase [from inception to February 2023] and 5 conference proceedings (from January 1990 to April 2023) were searched in this systematic review and meta-analysis. Study Selection: Randomized trials directly comparing SBT techniques in critically ill adults or children and reporting at least 1 clinical outcome were selected. Data Extraction and Synthesis: Paired reviewers independently screened citations, abstracted data, and assessed quality for the systematic review and meta-analysis using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA guidelines). Data were pooled using random-effects models. Main Outcomes and Measures: Primary outcomes included SBT success, extubation success, and reintubation. Results: The systematic review and meta-analysis identified 40 trials that included 6716 patients. Low-quality evidence (14 trials [n = 4459]) suggested that patients were not more likely to pass a pressure support (PS) compared with a T-piece SBT (risk ratio [RR], 1.04; 95% CI, 0.97-1.11; P = .31; I2 = 73%), unless 1 outlier trial accounting for all heterogeneity was excluded (RR, 1.09; 95% CI, 1.06-1.12; P < .001; I2 = 0% [13 trials; n = 3939]; moderate-quality evidence), but were significantly more likely to be successfully extubated (RR, 1.07; 95% CI, 1.04-1.10; P < .001; I2 = 0%; 16 trials [n = 4462]; moderate-quality evidence). Limited data (5 trials [n = 502]) revealed that patients who underwent automatic tube compensation/continuous positive airway pressure compared with PS SBTs had a significantly higher successful extubation rate (RR, 1.10; 95% CI, 1.00-1.21; P = .04; I2 = 0% [low-quality evidence]). Compared with T-piece SBTs, high-flow oxygen SBTs (3 trials [n = 386]) had significantly higher successful extubation (RR, 1.06; 95% CI, 1.00-1.11; P = .04; I2 = 0%) and lower reintubation (RR, 0.37; 95% CI, 0.21-0.65; P = <.001; I2 = 0% [both low-quality evidence]) rates. Credible subgroup effects were not found. Conclusions and Relevance: In this systematic review and meta-analysis, the findings suggest that patients undergoing PS compared with T-piece SBTs were more likely to be extubated successfully and more likely to pass an SBT, after exclusion of an outlier trial. Pressure support SBTs were not associated with increased risk of reintubation. Future trials should compare SBT techniques that maximize differences in inspiratory support.

How P. aeruginosa cells with diverse stator composition collectively swarm.

Swarming is a macroscopic phenomenon in which surface bacteria organize into a motile population. The flagellar motor that drives swarming in Pseudomonas aeruginosa is powered by stators MotAB and MotCD. Deletion of the MotCD stator eliminates swarming, whereas deletion of the MotAB stator enhances swarming. Interestingly, we measured a strongly asymmetric stator availability in the wild-type (WT) strain, with MotAB stators produced at an approximately 40-fold higher level than MotCD stators. However, utilization of MotCD stators in free swimming cells requires higher liquid viscosities, while MotAB stators are readily utilized at low viscosities. Importantly, we find that cells with MotCD stators are ~10× more likely to have an active motor compared to cells uses the MotAB stators. The spectrum of motility intermittency can either cooperatively shut down or promote flagellum motility in WT populations. In P. aeruginosa, transition from a static solid-like biofilm to a dynamic liquid-like swarm is not achieved at a single critical value of flagellum torque or stator fraction but is collectively controlled by diverse combinations of flagellum activities and motor intermittencies via dynamic stator utilization. Experimental and computational results indicate that the initiation or arrest of flagellum-driven swarming motility does not occur from individual fitness or motility performance but rather related to concepts from the "jamming transition" in active granular matter.IMPORTANCEIt is now known that there exist multifactorial influences on swarming motility for P. aeruginosa, but it is not clear precisely why stator selection in the flagellum motor is so important. We show differential production and utilization of the stators. Moreover, we find the unanticipated result that the two motor configurations have significantly different motor intermittencies: the fraction of flagellum-active cells in a population on average with MotCD is active ~10× more often than with MotAB. What emerges from this complex landscape of stator utilization and resultant motor output is an intrinsically heterogeneous population of motile cells. We show how consequences of stator recruitment led to swarming motility and how the stators potentially relate to surface sensing circuitry.

High-Flow Nasal Cannula Compared With Noninvasive Positive Pressure Ventilation in Acute Hypoxic Respiratory Failure: A Systematic Review and Meta-Analysis.

To evaluate the efficacy and cost-effectiveness of high-flow nasal cannula (HFNC) when compared with noninvasive positive pressure ventilation (NIPPV) in patients with acute hypoxic respiratory failure (AHRF). DATA SOURCES: We performed a comprehensive search of MEDLINE, Embase, CINAHL, the Cochrane library, and the international Health Technology Assessment database from inception to September 14, 2022. STUDY SELECTION: We included randomized control studies that compared HFNC to NIPPV in adult patients with AHRF. For clinical outcomes, we included only parallel group and crossover randomized control trials (RCTs). For economic outcomes, we included any study design that evaluated cost-effectiveness, cost-utility, or cost benefit analyses. DATA EXTRACTION: Clinical outcomes of interest included intubation, mortality, ICU and hospital length of stay (LOS), and patient-reported dyspnea. Economic outcomes of interest included costs, cost-effectiveness, and cost-utility. DATA SYNTHESIS: We included nine RCTs (n = 1,539 patients) and one cost-effectiveness study. Compared with NIPPV, HFNC may have no effect on the need for intubation (relative risk [RR], 0.93; 95% CI, 0.69-1.27; low certainty) and an uncertain effect on mortality (RR, 0.84; 95% CI, 0.59-1.21; very low certainty). In subgroup analysis, NIPPV delivered through the helmet interface-as opposed to the facemask interface-may reduce intubation compared with HFNC (p = 0.006; moderate credibility of subgroup effect). There was no difference in ICU or hospital LOS (both low certainty) and an uncertain effect on patient-reported dyspnea (very low certainty). We could make no conclusions regarding the cost-effectiveness of HFNC compared with NIPPV. CONCLUSIONS: HFNC and NIPPV may be similarly effective at reducing the need for intubation with an uncertain effect on mortality in hospitalized patients with hypoxemic respiratory failure. More research evaluating different interfaces in varying clinical contexts is needed to improve generalizability and precision of findings.

Conducting Prospective Research as a Trainee: Experiences with the DRIVE-SAFE Study.

Conducting clinical research during a 2-year critical care fellowship is a challenging endeavor. Fellows are often met with multiple barriers when considering clinical research projects during fellowship, including time, mentorship, resources, and clinical support. This paper presents the perspective and experiences of a group of critical care fellows who conducted the DRIVE-SAFE (Driving Pressure in Assisted Ventilation as a Predictor for Successful Liberation from Invasive Mechanical Ventilation) feasibility study, which aimed to determine measurable physiological variables that could be associated with lung injury and affect duration of mechanical ventilation. This paper provides a guide for trainees on how to conduct prospective clinical research at the bedside. We describe three key steps, including formulating a research question, developing appropriate methodology, and establishing outcomes. We also present the challenges that trainees may encounter when conducting prospective studies and how to overcome these challenges with proper mentorship, training, and collaboration with key stakeholders. These perspectives may provide useful guidance for current and future trainees interested in conducting prospective clinical research at the bedside.

Systemic Nonsteroidal Anti-Inflammatories for Analgesia in Postoperative Critical Care Patients: A Systematic Review and Meta-Analysis of Randomized Control Trials.

While opioids are part of usual care for analgesia in the ICU, there are concerns regarding excess use. This is a systematic review of nonsteroidal anti-inflammatory drugs (NSAIDs) use in postoperative critical care adult patients. DATA SOURCES: We searched Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, trial registries, Google Scholar, and relevant systematic reviews through March 2023. STUDY SELECTION: Titles, abstracts, and full texts were reviewed independently and induplicate by two investigators to identify eligible studies. We included randomized control trials (RCTs) that compared NSAIDs alone or as an adjunct to opioids for systemic analgesia. The primary outcome was opioid utilization. DATA EXTRACTION: In duplicate, investigators independently extracted study characteristics, patient demographics, intervention details, and outcomes of interest using predefined abstraction forms. Statistical analyses were conducted using Review Manager software Version 5.4. (The Cochrane Collaboration, Copenhagen, Denmark). DATA SYNTHESIS: We included 15 RCTs (n = 1,621 patients) for admission to the ICU for postoperative management after elective procedures. Adjunctive NSAID therapy to opioids reduced 24-hour oral morphine equivalent consumption by 21.4 mg (95% CI, 11.8-31.0 mg reduction; high certainty) and probably reduced pain scores (measured by Visual Analog Scale) by 6.1 mm (95% CI, 12.2 decrease to 0.1 increase; moderate certainty). Adjunctive NSAID therapy probably had no impact on the duration of mechanical ventilation (1.6 hr reduction; 95% CI, 0.4 hr to 2.7 reduction; moderate certainty) and may have no impact on ICU length of stay (2.1 hr reduction; 95% CI, 6.1 hr reduction to 2.0 hr increase; low certainty). Variability in reporting adverse outcomes (e.g., gastrointestinal bleeding, acute kidney injury) precluded their meta-analysis. CONCLUSIONS: In postoperative critical care adult patients, systemic NSAIDs reduced opioid use and probably reduced pain scores. However, the evidence is uncertain for the duration of mechanical ventilation or ICU length of stay. Further research is required to characterize the prevalence of NSAID-related adverse outcomes.

Doppler identified venous congestion in septic shock: protocol for an international, multi-centre prospective cohort study (Andromeda-VEXUS).

INTRODUCTION: Venous congestion is a pathophysiological state where high venous pressures cause organ oedema and dysfunction. Venous congestion is associated with worse outcomes, particularly acute kidney injury (AKI), for critically ill patients. Venous congestion can be measured by Doppler ultrasound at the bedside through interrogation of the inferior vena cava (IVC), hepatic vein (HV), portal vein (PV) and intrarenal veins (IRV). The objective of this study is to quantify the association between Doppler identified venous congestion and the need for renal replacement therapy (RRT) or death for patients with septic shock. METHODS AND ANALYSIS: This study is a prespecified substudy of the ANDROMEDA-SHOCK 2 (AS-2) randomised control trial (RCT) assessing haemodynamic resuscitation in septic shock and will enrol at least 350 patients across multiple sites. We will include adult patients within 4 hours of fulfilling septic shock definition according to Sepsis-3 consensus conference. Using Doppler ultrasound, physicians will interrogate the IVC, HV, PV and IRV 6-12 hours after randomisation. Study investigators will provide web-based educational sessions to ultrasound operators and adjudicate image acquisition and interpretation. The primary outcome will be RRT or death within 28 days of septic shock. We will assess the hazard of RRT or death as a function of venous congestion using a Cox proportional hazards model. Sub-distribution HRs will describe the hazard of RRT given the competing risk of death. ETHICS AND DISSEMINATION: We obtained ethics approval for the AS-2 RCT, including this observational substudy, from local ethics boards at all participating sites. We will report the findings of this study through open-access publication, presentation at international conferences, a coordinated dissemination strategy by investigators through social media, and an open-access workshop series in multiple languages. TRIAL REGISTRATION NUMBER: NCT05057611.

How individual P. aeruginosa cells with diverse stator distributions collectively form a heterogeneous macroscopic swarming population.

Swarming is a macroscopic phenomenon in which surface bacteria organize into a motile population. The flagellar motor that drives swarming in Pseudomonas aeruginosa is powered by stators MotAB and MotCD. Deletion of the MotCD stator eliminates swarming, whereas deletion of the MotAB stator enhances swarming. Interestingly, we measured a strongly asymmetric stator availability in the WT strain, with MotAB stators produced ∼40-fold more than MotCD stators. However, recruitment of MotCD stators in free swimming cells requires higher liquid viscosities, while MotAB stators are readily recruited at low viscosities. Importantly, we find that cells with MotCD stators are ∼10x more likely to have an active motor compared to cells without, so wild-type, WT, populations are intrinsically heterogeneous and not reducible to MotAB-dominant or MotCD-dominant behavior. The spectrum of motility intermittency can either cooperatively shut down or promote flagellum motility in WT populations. In P. aeruginosa , transition from a static solid-like biofilm to a dynamic liquid-like swarm is not achieved at a single critical value of flagellum torque or stator fraction but is collectively controlled by diverse combinations of flagellum activities and motor intermittencies via dynamic stator recruitment. Experimental and computational results indicate that the initiation or arrest of flagellum-driven swarming motility does not occur from individual fitness or motility performance but rather related to concepts from the 'jamming transition' in active granular matter. Importance: After extensive study, it is now known that there exist multifactorial influences on swarming motility in P. aeruginosa , but it is not clear precisely why stator selection in the flagellum motor is so important or how this process is collectively initiated or arrested. Here, we show that for P. aeruginosa PA14, MotAB stators are produced ∼40-fold more than MotCD stators, but recruitment of MotCD over MotAB stators requires higher liquid viscosities. Moreover, we find the unanticipated result that the two motor configurations have significantly different motor intermittencies, the fraction of flagellum-active cells in a population on average, with MotCD active ∼10x more often than MotAB. What emerges from this complex landscape of stator recruitment and resultant motor output is an intrinsically heterogeneous population of motile cells. We show how consequences of stator recruitment led to swarming motility, and how they potentially relate to surface sensing circuitry.

In vivo functional analysis and genetic modification of in vitro-derived mouse neutrophils.

Mature neutrophils are notoriously short-lived immune cells that cannot be genetically manipulated. Analysis of gene function therefore requires genetically modified animals, which is expensive, time-consuming, and costly in animal life. Analysis of gene function in neutrophils in a physiologically relevant context thus represents a significant problem in the field. We sought to overcome this obstruction in the field by developing a strategy for the analysis of gene function in neutrophils in a physiologically relevant context. Here, we demonstrate the functional relevance of in vitro conditional-Hoxb8 immortalized precursor-derived neutrophils. In vitro-derived neutrophils functionally resembled primary neutrophils, but critically, neutrophils generated in this way can be adoptively transferred into live animals and tracked during inflammatory responses using single-cell analysis to define functional attributes. We have validated this approach using CD11b-deficient neutrophils and replicated the key findings observed in gene-targeted animals and in naturally CD11b-deficient humans. Furthermore, we show that by retroviral transduction, one can generate stable alterations in the precursor cell lines and thus a continuous supply of functionally altered neutrophils. This novel technological advance offers for the first time the possibility of applying higher-throughput genetic modification and in vivo functional analysis to the neutrophil-lineage.