Intravenous Vitamin C in Adults with Sepsis in the Intensive Care Unit.

BACKGROUND: Studies that have evaluated the use of intravenous vitamin C in adults with sepsis who were receiving vasopressor therapy in the intensive care unit (ICU) have shown mixed results with respect to the risk of death and organ dysfunction. METHODS: In this randomized, placebo-controlled trial, we assigned adults who had been in the ICU for no longer than 24 hours, who had proven or suspected infection as the main diagnosis, and who were receiving a vasopressor to receive an infusion of either vitamin C (at a dose of 50 mg per kilogram of body weight) or matched placebo administered every 6 hours for up to 96 hours. The primary outcome was a composite of death or persistent organ dysfunction (defined by the use of vasopressors, invasive mechanical ventilation, or new renal-replacement therapy) on day 28. RESULTS: A total of 872 patients underwent randomization (435 to the vitamin C group and 437 to the control group). The primary outcome occurred in 191 of 429 patients (44.5%) in the vitamin C group and in 167 of 434 patients (38.5%) in the control group (risk ratio, 1.21; 95% confidence interval [CI], 1.04 to 1.40; P = 0.01). At 28 days, death had occurred in 152 of 429 patients (35.4%) in the vitamin C group and in 137 of 434 patients (31.6%) in the placebo group (risk ratio, 1.17; 95% CI, 0.98 to 1.40) and persistent organ dysfunction in 39 of 429 patients (9.1%) and 30 of 434 patients (6.9%), respectively (risk ratio, 1.30; 95% CI, 0.83 to 2.05). Findings were similar in the two groups regarding organ-dysfunction scores, biomarkers, 6-month survival, health-related quality of life, stage 3 acute kidney injury, and hypoglycemic episodes. In the vitamin C group, one patient had a severe hypoglycemic episode and another had a serious anaphylaxis event. CONCLUSIONS: In adults with sepsis receiving vasopressor therapy in the ICU, those who received intravenous vitamin C had a higher risk of death or persistent organ dysfunction at 28 days than those who received placebo. (Funded by the Lotte and John Hecht Memorial Foundation; LOVIT ClinicalTrials.gov number, NCT03680274.).

A Canadian survey of perceptions and practices related to ordering of blood tests in the intensive care unit.

PURPOSE: The ordering of routine blood test panels in advance is common in intensive care units (ICUs), with limited consideration of the pretest probability of finding abnormalities. This practice contributes to anemia, false positive results, and health care costs. We sought to understand practices and attitudes of Canadian adult intensivists regarding ordering of blood tests in critically ill patients. METHODS: We conducted a nationwide Canadian cross-sectional survey consisting of 15 questions assessing three domains (global perceptions, test ordering, daily practice), plus 11 demographic questions. The target sample was one intensivist per adult ICU in Canada. We summarized responses using descriptive statistics and present data as mean with standard deviation (SD) or count with percentage as appropriate. RESULTS: Over seven months, 80/131 (61%) physicians responded from 77 ICUs, 50% of which were from Ontario. Respondents had a mean (SD) clinical experience of 12 (9) years, and 61% worked in academic centres. When asked about their perceptions of how frequently unnecessary blood tests are ordered, 61% responded "sometimes" and 23% responded "almost always." Fifty-seven percent favoured ordering complete blood counts one day in advance. Only 24% of respondents believed that advanced blood test ordering frequently led to changes in management. The most common factors perceived to influence blood test ordering in the ICU were physician preferences, institutional patterns, and order sets. CONCLUSION: Most respondents to this survey perceived that unnecessary blood testing occurs in the ICU. The survey identified possible strategies to decrease the number of blood tests.

RéSUMé: OBJECTIF: La prescription à l'avance de tests sanguins de routine est courante dans les unités de soins intensifs (USI), avec une prise en compte limitée de la probabilité de découverte d'anomalies avant le test. Cette pratique contribue à l'anémie, aux résultats faussement positifs et aux coûts des soins de santé. Nous avons cherché à comprendre les pratiques et les attitudes des intensivistes pour adultes au Canada en ce qui concerne la prescription d'analyses sanguines chez la patientèle gravement malade. MéTHODE: Nous avons mené un sondage transversal à l'échelle nationale au Canada en posant 15 questions évaluant trois domaines (perceptions globales, commande de tests, pratique quotidienne), ainsi que 11 questions démographiques. L'échantillon cible était composé d'un·e intensiviste par unité de soins intensifs pour adultes au Canada. Nous avons résumé les réponses à l'aide de statistiques descriptives et présenté les données sous forme de moyennes avec écarts type (ET) ou de dénombrements avec pourcentages, selon le cas. RéSULTATS: Sur une période de sept mois, 80 médecins sur 131 (61%) ont répondu dans 77 unités de soins intensifs, dont 50% en Ontario. Les répondant·es avaient une expérience clinique moyenne (ET) de 12 (9) ans, et 61% travaillaient dans des centres universitaires. Lorsqu'on leur a demandé ce qu'ils ou elles pensaient de la fréquence à laquelle des tests sanguins inutiles étaient prescrits, 61% ont répondu « parfois ¼ et 23% ont répondu « presque toujours ¼. Cinquante-sept pour cent étaient en faveur de la réalisation d'une formule sanguine complète un jour à l'avance. Seulement 24% des personnes interrogées estimaient que la prescription de tests sanguins à l'avance entraînait fréquemment des changements dans la prise en charge. Les facteurs les plus souvent perçus comme influençant la prescription d'analyses sanguines à l'unité de soins intensifs étaient les préférences des médecins, les habitudes institutionnelles et les ensembles d'ordonnances. CONCLUSION: La plupart des répondant·es à ce sondage ont l'impression que des tests sanguins inutiles sont prescrits aux soins intensifs. L'enquête a permis d'identifier des stratégies possibles pour réduire le nombre de tests sanguins.

Comparative Effectiveness of Protective Ventilation Strategies for Moderate and Severe Acute Respiratory Distress Syndrome. A Network Meta-Analysis.

Rationale: Choosing the best ventilation strategy for acute respiratory distress syndrome (ARDS) is complex, yet it is highly relevant to clinicians during a respiratory pandemic. Objectives: To compare the effects of low Vt, high Vt, high positive end-expiratory pressure (PEEP), prone ventilation, high-frequency oscillation, and venovenous extracorporeal membrane oxygenation (VV ECMO) on mortality in ARDS. Methods: We performed a network meta-analysis of randomized trials. We applied the Grading of Recommendations Assessment, Development and Evaluation methodology to discern the relative effect of interventions on mortality. Measurements and Main Results: We analyzed 34 trials including 9,085 adults with primarily moderate-to-severe ARDS (median baseline PaO2/FiO2, 118; interquartile range, 110-143). Prone positioning combined with low Vt was the best strategy (risk ratio [RR], 0.74 [95% confidence interval (CI), 0.60-0.92] vs. low Vt; high certainty). VV ECMO was also rated among the best (RR, 0.78 [95% CI, 0.58-1.05] vs. low Vt; RR, 0.66; [95% CI, 0.49-0.88] vs. high Vt) but was rated with lower certainty because VV ECMO was restricted to very severe ARDS (mean baseline PaO2/FiO2<75). High PEEP combined with low Vt was rated intermediately (RR, 0.91 [95% CI, 0.81-1.03] vs. low Vt; low certainty; RR, 0.77 [95% CI, 0.65-0.91] vs. high Vt; moderate certainty). High Vt was rated worst (RR, 1.19 [95% CI, 1.02-1.37] vs. low Vt; moderate certainty), and we found no support for high-frequency oscillation or high Vt with prone ventilation. Conclusions: These findings suggest that combining low Vt with prone ventilation is associated with the greatest reduction in mortality for critically ill adults with moderate-to-severe ARDS.

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.

Organ Donation at the End of Life: Experiences From the 3 Wishes Project.

PURPOSE: The 3 Wishes Project (3WP) promotes holistic end-of-life care in the intensive care unit (ICU) to honor dying patients, support families, and encourage clinician compassion. Organ donation is a wish that is sometimes made by, or on behalf of, critically ill patients. Our objective was to describe the interface between the 3WP and organ donation as experienced by families, clinicians, and organ donation coordinators. METHODS: In a multicenter evaluation of the 3WP in 4 Canadian ICUs, we conducted a thematic analysis of transcripts from interviews and focus groups with clinicians, organ donation coordinators, and families of dying or died patients for whom donation was considered. RESULTS: We analyzed transcripts from 26 interviews and 2 focus groups with 18 family members, 17 clinicians, and 6 organ donation coordinators. The central theme describes the mutual goals of the 3WP and organ donation-emphasizing personhood and agency across the temporal continuum of care. During family decision-making, conversations encouraged by the 3WP can facilitate preliminary discussions about donation. During preparation for donation, memory-making activities supported by the 3WP redirect focus toward personhood. During postmortem family care, the 3WP supports families, including when donation is unsuccessful, and highlights aspirational pursuits of donation while encouraging reflections on other fulfilled wishes. CONCLUSIONS: Organ donation and the 3WP provide complementary opportunities to engage in value-based conversations during the dying process. The shared values of these programs may help to incorporate organ donation and death into a person's life narrative and incorporate new life into a person's death narrative.

Ventilator Weaning and Discontinuation Practices for Critically Ill Patients.

Importance: Although most critically ill patients receive invasive mechanical ventilation (IMV), few studies have characterized how IMV is discontinued in practice. Objective: To describe practice variation in IMV discontinuation internationally, associations between initial discontinuation events and outcomes, and factors associated with the use of select discontinuation strategies and failed initial spontaneous breathing trials (SBTs). Design, Setting, and Participants: Prospective, multinational, observational study of critically ill adults who received IMV for at least 24 hours from 142 intensive care units (ICUs) in 19 countries within 6 regions (27 in Canada, 23 in India, 22 in the UK, 26 in Europe, 21 in Australia/New Zealand, and 23 in the US). Exposures: Receiving IMV. Main Outcomes and Measures: Primary analyses characterized types of initial IMV discontinuation events (extubation, SBT, or tracheostomy) and associations with clinical outcomes (including duration of ventilation, ICU and hospital mortality, and ICU and hospital length of stay). Secondary analyses examined the associations between SBT outcome and SBT timing and clinical outcomes. Results: Among 1868 patients (median [interquartile range] age, 61.8 [48.9-73.1] years; 1173 [62.8%] men) 424 (22.7%) underwent direct extubation, 930 (49.8%) had an initial SBT (761 [81.8%] successful), 150 (8.0%) underwent direct tracheostomy, and 364 (19.5%) died before a weaning attempt. Across regions, there was variation in the use of written directives to guide care, daily screening, SBT techniques, ventilator modes, and the roles played by clinicians involved in weaning. Compared with initial direct extubation, patients who had an initial SBT had higher ICU mortality (20 [4.7%] vs 96 [10.3%]; absolute difference, 5.6% [95% CI, 2.6%-8.6%]), longer duration of ventilation (median of 2.9 vs 4.1 days; absolute difference, 1.2 days [95% CI, 0.7-1.6]), and longer ICU stay (median of 6.7 vs 8.1 days; absolute difference, 1.4 days [95% CI, 0.8-2.4]). Patients whose initial SBT failed (vs passed) had higher ICU mortality (29 [17.2%] vs 67 [8.8%]; absolute difference, 8.4% [95% CI, 2.0%-14.7%]), longer duration of ventilation (median of 6.1 vs 3.5 days; absolute difference, 2.6 days [95% CI, 1.6-3.6]), and longer ICU stay (median of 10.6 vs 7.7 days; absolute difference, 2.8 days [95% CI, 1.1-5.2]). Compared with patients who underwent early initial SBTs, patients who underwent late initial SBTs (>2.3 days after intubation) had longer duration of ventilation (median of 2.1 vs 6.1 days; absolute difference, 4.0 days [95% CI, 3.7-4.5]), longer ICU stay (median of 5.9 vs 10.8 days; absolute difference, 4.9 days [95% CI, 4.0-6.3]), and longer hospital stay (median of 14.3 vs 22.8 days; absolute difference, 8.5 days [95% CI, 6.0-11.0]). Conclusions and Relevance: In this observational study of invasive mechanical ventilation discontinuation in 142 ICUs in Canada, India, the UK, Europe, Australia/New Zealand, and the US from 2013 to 2016, weaning practices varied internationally. Trial Registration: ClinicalTrials.gov Identifier: NCT03955874.

Research Collaboration in Pediatric Critical Care Randomized Controlled Trials: A Social Network Analysis of Coauthorship.

OBJECTIVES: Clinical research is a collaborative enterprise; researchers benefit from the expertise, experience, and resources of their collaborators. We sought to describe the extent and patterns of collaboration among pediatric critical care trialists, and to identify the most influential individuals, centers, and countries. DESIGN: Social network analysis of coauthorship. DATA SOURCES: Publications of pediatric critical care randomized controlled trials (1986-2018). DATA EXTRACTION: We manually extracted the names of all authors and their affiliations. We used productivity (number of randomized controlled trials), influence (number of citations), and four measures of prominence in the social network (degree, betweenness, closeness, and eigenvector centrality) to identify the most influential individuals. MEASUREMENTS AND MAIN RESULTS: From 415 randomized controlled trials in pediatric critical care, we identified 2,176 trialists from 377 centers in 43 countries. The coauthorship network is highly disconnected and dominated by a single large cluster of trialists publishing 142 (34%) of the randomized controlled trials. However, 119 (29%) of the randomized controlled trials were published by 28 smaller clusters-a median (interquartile range) of 3 (2-4) randomized controlled trials each. The remaining 154 (37%) randomized controlled trials were coauthored by researchers publishing a single randomized controlled trial each. This overall structure has remained constant with the publication of new randomized controlled trials over 33 years. The most influential trialists and centers varied according to the metric we used; only one trialist and three centers ranked in the top 10 for all measures of influence. Thirty-five of the 40 trialists (88%) ranking in the top 10 of any of the measures were from the United States, the United Kingdom, and Canada. CONCLUSIONS: Pediatric critical care has made considerable progress in the number of trialists and randomized controlled trials, but the research enterprise remains highly clustered and fragmented, particularly geographically. Efforts to further increase the quantity and quality of research in the field should include steps to increase the level and range of collaboration.

Worldwide management of donors after neurological death: a systematic review and narrative synthesis of guidelines.

OBJECTIVE: The objectives of this study were to systematically identify and describe guidelines for the care of neurologically deceased donors and to evaluate their methodological quality, with the aim of informing and supporting the new Canadian guidelines for the management of organ donors. METHODOLOGY: Following a systematic search, we included any document endorsed by an organ donation organization, a professional society, or a government, that aims to direct the medical management of adult, neurologically deceased, multi-organ donors. We extracted recommendations pertaining to six domains: the autonomic storm, hemodynamic instability, hormone supplementation, ventilation, blood product transfusions, and general intensive care unit (ICU) care. Methodological quality of the guidelines was assessed by the validated AGREE-II tool. MAIN FINDINGS: This review includes 27 clinical practice guidelines representing 26 countries published between 1993 and 2019. Using the AGREE-II validated tool for the evaluation of guidelines' quality, documents generally scored well on their scope and clarity of presentation. Nevertheless, quality was limited in terms of the scientific rigor of guideline development. Recommendations varied substantially across the domains of managing the autonomic storm, subsequent management of hemodynamic instability, hormone therapy, mechanical ventilation, blood product transfusion, and general ICU care. We found consistent recommendations for low tidal volume ventilation subsequent to the publication of a landmark clinical trial. CONCLUSION: Highly inconsistent recommendations for deceased donor care summarized in this review likely reflect the relatively slow emergence of high-quality clinical research in this field, as well as a late uptake of recent validated guideline methodology. Even in this context of few randomized-controlled trials, our group supported the need for new Canadian guidelines for the management of organ donors that follow rigorous recognized methodology and grading of the evidence. TRIAL REGISTRATION: PROSPERO (CRD42018084012); registered 25 February 2016.

RéSUMé: OBJECTIF: Les objectifs de cette étude étaient d'identifier et de décrire de façon systématique les lignes directrices concernant les soins à prodiguer aux donneurs suivant un décès neurologique et d'évaluer leur qualité méthodologique, avec pour but d'informer et d'appuyer les nouvelles lignes directrices canadiennes de prise en charge des donneurs d'organes. MéTHODOLOGIE: À la suite d'une recherche systématique, nous avons inclus tout document endossé par un organisme de dons d'organes, une société professionnelle ou un gouvernement et ayant pour but d'orienter la prise en charge médicale des donneurs adultes d'organes multiples à la suite d'un décès neurologique. Nous avons extrait les recommandations touchant six domaines : la tempête catécholaminergique, l'instabilité hémodynamique, la supplémentation hormonale, la ventilation, les transfusions de produits sanguins et les soins généraux à l'unité de soins intensifs (USI). La qualité méthodologique des lignes directrices a été évaluée avec l'outil validé AGREE-II. CONSTATIONS PRINCIPALES: Cette revue porte sur 27 guides d'exercice cliniques représentant 26 pays et publiés entre 1993 et 2019. En se fondant sur l'outil validé AGREE-II pour l'évaluation de la qualité des lignes directrices, les documents ont en règle générale obtenu un bon score en ce qui touchait à leurs objectifs et à la clarté de leur présentation. Toutefois, la qualité était limitée en matière de rigueur scientifique employée pour la mise au point des lignes directrices. Les recommandations variaient considérablement concernant les questions pertinentes à la prise en charge de la tempête catécholaminergique, à la prise en charge subséquente de l'instabilité hémodynamique, à l'hormonothérapie, à la ventilation mécanique, à la transfusion de produits sanguins, et aux soins généraux à l'USI. À la suite de la publication d'une étude clinique importante, les recommandations concernant la ventilation à volume courant bas étaient constantes. CONCLUSION: Le manque de cohérence des lignes directrices touchant les soins aux donneurs décédés résumées dans cette revue est probablement le reflet de l'émergence relativement lente de recherches cliniques de qualité élevée dans ce domaine, ainsi que de l'adoption tardive des méthodologies récentes et validées pour l'élaboration de lignes directrices. Même dans le contexte actuel de rareté d'études randomisées contrôlées, notre groupe appuie la nécessité de nouvelles lignes directrices canadiennes concernant la prise en charge des donneurs d'organes qui respectent une méthodologie reconnue et rigoureuse ainsi qu'une classification des données probantes. ENREGISTREMENT DE L'éTUDE: PROSPERO (CRD42018084012); enregistrée le 25 février 2016.

Using bioimpedance analysis to assess intensive care unit patients with sepsis in the post-resuscitation period: a prospective multicentre observational study.

PURPOSE: Clinicians lack well-validated, non-invasive, objective tools to guide volume management in the post-resuscitative period. Bioimpedance analysis (BIA) represents a novel method for guiding fluid management. We studied the relationship of BIA vector length (VL), an indicator of volume status, to the need for mechanical ventilation in patients with sepsis. METHODS: This is a multicentre prospective observational study at four Canadian ICUs. We examined adult patients admitted to the ICU within 72 hr of a sepsis diagnosis. Patients underwent daily BIA measurements for 30 days, until discharge from the ICU, or until death. Our primary outcome was the ongoing need for invasive mechanical ventilation, and we examined the association with VL using a generalized estimating equation. Our secondary analyses were targeted to determine an association between VL and other measures of volume status and acute kidney injury (AKI). RESULTS: We enrolled 159 patients from four centres over 27 months. The mean (standard deviation [SD]) age was 64 (15) yr with a mean (SD) APACHE (acute physiology, age, chronic health evaluation) II score of 25 (10); 57% (n = 91) were male. A 50-unit (ohm·m) increase in VL over any time period was associated with a 30% decrease in the probability of requiring invasive mechanical ventilation (P < 0.03). Volume expansion, indicated by a shorter VL, correlated with higher edema scores (r = - 0.31; P < 0.001) and higher net 24-hr fluid balance (r = - 0.27, P < 0.001). Patients with AKI had a shorter overall VL (r = - 0.23; P = 0.003). CONCLUSIONS: An increase in VL over time is associated with a decrease in probability of requiring invasive mechanical ventilation. Vector length correlates with other commonly used volume assessment methods in post-resuscitation patients with sepsis.

Variability in deceased donor care in Canada: a report of the Canada-DONATE cohort study.

PURPOSE: Canadian donor management practices have not been reported. Our aim was to inform clinicians and other stakeholders about the range of current practices. METHODS: This prospective observational cohort study enrolled consecutive, newly consented organ donors from August 1 2015 to July 31 2018 at 27 academic and five community adult intensive care units in British Columbia, Alberta, Ontario, and Quebec. Research staff prospectively recorded donor management data. Provincial organ donation organizations verified the organs donated. We formally compared practices across provinces. RESULTS: Over a median collection period of eight months, 622 potential donors were classified at baseline as having neurologic determination of death (NDD donors; n = 403) or circulatory death (DCD donors; n = 219). Among NDD donors, 85.6% underwent apnea testing (rarely with carbon dioxide insufflation), 33.2% underwent ancillary testing, and subsequent therapeutic hypothermia (34-35°C) was rare. Neurologic determination of death donors were more hemodynamically unstable with most having received vasopressin and norepinephrine infusions, with a large majority having received high-dose corticosteroids and intravenous thyroxine. Among DCD donors, 61.6% received corticosteroids, and 8.9% received thyroxine. Most donors did not receive lung-protective ventilation strategies. Invasive procedures after donation consent included bronchoscopy (71.7%), cardiac catheterization (NDD donors only; 21.3%), and blood transfusions (19.3%). Physicians ordered intravenous antemortem heparin for 94.8% of DCD donors. The cohort donated 1,629 organs resulting in 1,532 transplants. Case selection, death determinations, and hormone, nutrition and heparin practices all varied across provinces. CONCLUSION: These study findings highlight areas for knowledge translation and further clinical research. Interprovincial discrepancies will likely pose unique challenges to national randomized trials. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03114436); registered 10 April, 2017.

RéSUMé: OBJECTIF: Les pratiques canadiennes de prise en charge des donneurs n'ont pas été rapportées. Notre objectif était d'informer les cliniciens et autres parties intéressées quant à l'éventail des pratiques actuelles. MéTHODE: Cette étude de cohorte observationnelle et prospective a recruté des donneurs d'organes consécutifs ayant récemment consenti au don entre le 1er août 2015 et le 31 juillet 2018 dans 27 unités de soins intensifs universitaires et cinq unités de soins intensifs pour adultes en milieu communautaire en Colombie-Britannique, en Alberta, en Ontario et au Québec. Le personnel de recherche a enregistré de manière prospective les données de prise en charge des donneurs. Les organismes de dons d'organes provinciaux ont vérifié les organes donnés. Nous avons formellement comparé les pratiques d'une province à l'autre. RéSULTATS: Sur une période médiane de collecte de huit mois, 622 donneurs potentiels ont été catégorisés au départ comme ayant un diagnostic de décès neurologique (donneurs DDN; n = 403) ou un décès cardiocirculatoire (donneurs DDC; n = 219). Parmi les donneurs DDN, 85,6 % ont subi un test d'apnée (rarement avec insufflation de dioxyde de carbone), 33,2 % ont subi des tests complémentaires, et une hypothermie thérapeutique subséquente (34-35°C) était rare. Les donneurs par diagnostic de décès neurologique étaient plus instables hémodynamiquement, la plupart ayant reçu des perfusions de vasopressine et de norépinéphrine, et une vaste majorité de ces donneurs ont reçu des corticostéroïdes à forte dose ainsi que de la thyroxine intraveineuse. Parmi les donneurs par DDC, 61,6 % avaient reçu des corticostéroïdes, et 8,9 % de la thyroxine. La plupart des donneurs n'avaient pas bénéficié de stratégies de ventilation protectrice des poumons. Les interventions invasives réalisées après le consentement au don comprenaient la bronchoscopie (71,7 %), le cathétérisme cardiaque (donneurs DDN seulement; 21,3 %) et les transfusions sanguines (19,3 %). Les médecins ont prescrit de l'héparine intraveineuse ante mortem chez 94,8 % des donneurs DDC. La cohorte a donné 1629 organes, résultant en 1532 greffes. La sélection de cas, la détermination de décès et les pratiques hormonales, nutritionnelles et hépariniques variaient toutes d'une province à l'autre. CONCLUSION: Ces résultats soulignent des domaines propices à la transmission de connaissances et aux recherches cliniques plus poussées. Les différences interprovinciales poseront probablement des défis uniques pour les études randomisées nationales. Enregistrement de l'étude : www.clinicaltrials.gov (NCT03114436); enregistrée le 10 avril 2017.

Atraumatic versus conventional lumbar puncture needles: a systematic review and meta-analysis.

BACKGROUND: Atraumatic needles have been proposed to lower complication rates after lumbar puncture. However, several surveys indicate that clinical adoption of these needles remains poor. We did a systematic review and meta-analysis to compare patient outcomes after lumbar puncture with atraumatic needles and conventional needles. METHODS: In this systematic review and meta-analysis, we independently searched 13 databases with no language restrictions from inception to Aug 15, 2017, for randomised controlled trials comparing the use of atraumatic needles and conventional needles for any lumbar puncture indication. Randomised trials comparing atraumatic and conventional needles in which no dural puncture was done (epidural injections) or without a conventional needle control group were excluded. We screened studies and extracted data from published reports independently. The primary outcome of postdural-puncture headache incidence and additional safety and efficacy outcomes were assessed by random-effects and fixed-effects meta-analysis. This study is registered with the International Prospective Register of Systematic Reviews, number CRD42016047546. FINDINGS: We identified 20 241 reports; after exclusions, 110 trials done between 1989 and 2017 from 29 countries, including a total of 31 412 participants, were eligible for analysis. The incidence of postdural-puncture headache was significantly reduced from 11·0% (95% CI 9·1-13·3) in the conventional needle group to 4·2% (3·3-5·2) in the atraumatic group (relative risk 0·40, 95% CI 0·34-0·47, p<0·0001; I2=45·4%). Atraumatic needles were also associated with significant reductions in the need for intravenous fluid or controlled analgesia (0·44, 95% CI 0·29-0·64; p<0·0001), need for epidural blood patch (0·50, 0·33-0·75; p=0·001), any headache (0·50, 0·43-0·57; p<0·0001), mild headache (0·52, 0·38-0·70; p<0·0001), severe headache (0·41, 0·28-0·59; p<0·0001), nerve root irritation (0·71, 0·54-0·92; p=0·011), and hearing disturbance (0·25, 0·11-0·60; p=0·002). Success of lumbar puncture on first attempt, failure rate, mean number of attempts, and the incidence of traumatic tap and backache did not differ significantly between the two needle groups. Prespecified subgroup analyses of postdural-puncture headache revealed no interactions between needle type and patient age, sex, use of prophylactic intravenous fluid, needle gauge, patient position, indication for lumbar puncture, bed rest after puncture, or clinician specialty. These results were rated high-quality evidence as examined using the grading of recommendations assessment, development, and evaluation. INTERPRETATION: Among patients who had lumbar puncture, atraumatic needles were associated with a decrease in the incidence of postdural-puncture headache and in the need for patients to return to hospital for additional therapy, and had similar efficacy to conventional needles. These findings offer clinicians and stakeholders a comprehensive assessment and high-quality evidence for the safety and efficacy of atraumatic needles as a superior option for patients who require lumbar puncture. FUNDING: None.

Frequency of Screening for Weaning From Mechanical Ventilation: Two Contemporaneous Proof-of-Principle Randomized Controlled Trials.

OBJECTIVES: It is unknown whether more frequent screening of invasively ventilated patients, identifies patients earlier for a spontaneous breathing trial, and shortens the duration of ventilation. We assessed the feasibility of conducting a large trial to evaluate screening frequency in critically ill adults in the North American context. DESIGN: We conducted two contemporaneous, multicenter, pilot, randomized controlled trials (the LibeRation from MEchanicaL VEntilAtion and ScrEening Frequency [RELEASE] and Screening Elderly PatieNts For InclusiOn in a Weaning [SENIOR] trials) to address concerns regarding the potential for higher enrollment, fewer adverse events, and better outcomes in younger patients. SETTING: Ten and 11 ICUs in Canada, respectively. PATIENTS: Parallel trials of younger (RELEASE < 65 yr) and older (SENIOR ≥ 65 yr) critically ill adults invasively ventilated for at least 24 hours. INTERVENTIONS: Each trial compared once daily screening to "at least twice daily" screening led by respiratory therapists. MEASUREMENTS AND MAIN RESULTS: In both trials, we evaluated recruitment (aim: 1-2 patients/month/ICU) and consent rates, reasons for trial exclusion, protocol adherence (target: ≥ 80%), crossovers (aim: ≤ 10%), and the effect of the alternative screening frequencies on adverse events and clinical outcomes. We included 155 patients (53 patients [23 once daily, 30 at least twice daily] in RELEASE and 102 patients [54 once daily, 48 at least twice daily] in SENIOR). Between trials, we found similar recruitment rates (1.32 and 1.26 patients/month/ICU) and reasons for trial exclusion, high consent and protocol adherence rates (> 92%), infrequent crossovers, and few adverse events. Although underpowered, at least twice daily screening was associated with a nonsignificantly faster time to successful extubation and more successful extubations but significantly increased use of noninvasive ventilation in both trials combined. CONCLUSIONS: Similar recruitment and consent rates, few adverse events, and comparable outcomes in younger and older patients support conduct of a single large trial in North American ICUs assessing the net clinical benefits associated with more frequent screening.

Patient and Family Engagement in the ICU. Untapped Opportunities and Underrecognized Challenges.

The call for meaningful patient and family engagement in health care and research is gaining impetus. Healthcare institutions and research funding agencies increasingly encourage clinicians and researchers to work actively with patients and their families to advance clinical care and research. Engagement is increasingly mandated by healthcare organizations and is becoming a prerequisite for research funding. In this article, we review the rationale and the current state of patient and family engagement in patient care and research in the ICU. We identify opportunities to strengthen engagement in patient care by promoting greater patient and family involvement in care delivery and supporting their participation in shared decision-making. We also identify challenges related to patient willingness to engage, barriers to participation, participant risks, and participant expectations. To advance engagement, clinicians and researchers can develop the science behind engagement in the ICU context and demonstrate its impact on patient- and process-related outcomes. In addition, we provide practical guidance on how to engage, highlight features of successful engagement strategies, and identify areas for future research. At present, enormous opportunities remain to enhance engagement across the continuum of ICU care and research.

A mixed-methods study of organ donation in the intensive care unit: 22 actionable practices to improve organ donation.

PURPOSE: Rates of organ donation vary between otherwise comparable intensive care units (ICUs) suggesting that the process of donation must vary between ICUs. The purpose of this study was to describe the process of organ donation from the perspective of ICU staff, identify important drivers of successful donation, and develop strategies to improve the process of donation. METHODS: We conducted qualitative interviews with 32 ICU staff, including physicians, nurses, and respiratory therapists, using an interview guide developed from previous studies on organ donation. Using a qualitative descriptive approach, we coded interviews using qualitative content analysis. We integrated findings from the interviews in a mixed-methods analysis with previously published data from a document analysis and cross-sectional survey to identify practices that may enhance organ donation in the ICU. RESULTS: Five major themes important to the organ donation process emerged from the interviews: i) staff relationship with organ donation coordinators; ii) standardized processes; iii) ICU staff beliefs; iv) integration of donation and high quality end-of-life care; v) feedback and staff support. In the mixed-methods analysis, we identified 22 actionable practices to enhance the process of organ donation in the ICU. CONCLUSION: Incorporating the perspectives of ICU staff, we were able to identify 22 practice changes that may have a significant cumulative impact on donation outcomes. Future research is required to evaluate whether these findings account for the variability of donation rates between otherwise comparable ICUs.

Driving pressure and survival in the acute respiratory distress syndrome.

BACKGROUND: Mechanical-ventilation strategies that use lower end-inspiratory (plateau) airway pressures, lower tidal volumes (VT), and higher positive end-expiratory pressures (PEEPs) can improve survival in patients with the acute respiratory distress syndrome (ARDS), but the relative importance of each of these components is uncertain. Because respiratory-system compliance (CRS) is strongly related to the volume of aerated remaining functional lung during disease (termed functional lung size), we hypothesized that driving pressure (ΔP=VT/CRS), in which VT is intrinsically normalized to functional lung size (instead of predicted lung size in healthy persons), would be an index more strongly associated with survival than VT or PEEP in patients who are not actively breathing. METHODS: Using a statistical tool known as multilevel mediation analysis to analyze individual data from 3562 patients with ARDS enrolled in nine previously reported randomized trials, we examined ΔP as an independent variable associated with survival. In the mediation analysis, we estimated the isolated effects of changes in ΔP resulting from randomized ventilator settings while minimizing confounding due to the baseline severity of lung disease. RESULTS: Among ventilation variables, ΔP was most strongly associated with survival. A 1-SD increment in ΔP (approximately 7 cm of water) was associated with increased mortality (relative risk, 1.41; 95% confidence interval [CI], 1.31 to 1.51; P<0.001), even in patients receiving "protective" plateau pressures and VT (relative risk, 1.36; 95% CI, 1.17 to 1.58; P<0.001). Individual changes in VT or PEEP after randomization were not independently associated with survival; they were associated only if they were among the changes that led to reductions in ΔP (mediation effects of ΔP, P=0.004 and P=0.001, respectively). CONCLUSIONS: We found that ΔP was the ventilation variable that best stratified risk. Decreases in ΔP owing to changes in ventilator settings were strongly associated with increased survival. (Funded by Fundação de Amparo e Pesquisa do Estado de São Paulo and others.).

Microbial dysbiosis and mortality during mechanical ventilation: a prospective observational study.

BACKGROUND: Host-associated microbial communities have important roles in tissue homeostasis and overall health. Severe perturbations can occur within these microbial communities during critical illness due to underlying diseases and clinical interventions, potentially influencing patient outcomes. We sought to profile the microbial composition of critically ill mechanically ventilated patients, and to determine whether microbial diversity is associated with illness severity and mortality. METHODS: We conducted a prospective, observational study of mechanically ventilated critically ill patients with a high incidence of pneumonia in 2 intensive care units (ICUs) in Hamilton, Canada, nested within a randomized trial for the prevention of healthcare-associated infections. The microbial profiles of specimens from 3 anatomical sites (respiratory, and upper and lower gastrointestinal tracts) were characterized using 16S ribosomal RNA gene sequencing. RESULTS: We collected 65 specimens from 34 ICU patients enrolled in the trial (29 endotracheal aspirates, 26 gastric aspirates and 10 stool specimens). Specimens were collected at a median time of 3 days (lower respiratory tract and gastric aspirates; interquartile range [IQR] 2-4) and 6 days (stool; IQR 4.25-6.75) following ICU admission. We observed a loss of biogeographical distinction between the lower respiratory tract and gastrointestinal tract microbiota during critical illness. Moreover, microbial diversity in the respiratory tract was inversely correlated with APACHE II score (r = - 0.46, p = 0.013) and was associated with hospital mortality (Median Shannon index: Discharged alive; 1.964 vs. Deceased; 1.348, p = 0.045). CONCLUSIONS: The composition of the host-associated microbial communities is severely perturbed during critical illness. Reduced microbial diversity reflects high illness severity and is associated with mortality. Microbial diversity may be a biomarker of prognostic value in mechanically ventilated patients. TRIAL REGISTRATION: ClinicalTrials.gov ID NCT01782755 . Registered February 4 2013.

Severity of Hypoxemia and Effect of High-Frequency Oscillatory Ventilation in Acute Respiratory Distress Syndrome.

RATIONALE: High-frequency oscillatory ventilation (HFOV) is theoretically beneficial for lung protection, but the results of clinical trials are inconsistent, with study-level meta-analyses suggesting no significant effect on mortality. OBJECTIVES: The aim of this individual patient data meta-analysis was to identify acute respiratory distress syndrome (ARDS) patient subgroups with differential outcomes from HFOV. METHODS: After a comprehensive search for trials, two reviewers independently identified randomized trials comparing HFOV with conventional ventilation for adults with ARDS. Prespecified effect modifiers were tested using multivariable hierarchical logistic regression models, adjusting for important prognostic factors and clustering effects. MEASUREMENTS AND MAIN RESULTS: Data from 1,552 patients in four trials were analyzed, applying uniform definitions for study variables and outcomes. Patients had a mean baseline PaO2/FiO2 of 114 ± 39 mm Hg; 40% had severe ARDS (PaO2/FiO2 <100 mm Hg). Mortality at 30 days was 321 of 785 (40.9%) for HFOV patients versus 288 of 767 (37.6%) for control subjects (adjusted odds ratio, 1.17; 95% confidence interval, 0.94-1.46; P = 0.16). This treatment effect varied, however, depending on baseline severity of hypoxemia (P = 0.0003), with harm increasing with PaO2/FiO2 among patients with mild-moderate ARDS, and the possibility of decreased mortality in patients with very severe ARDS. Compliance and body mass index did not modify the treatment effect. HFOV increased barotrauma risk compared with conventional ventilation (adjusted odds ratio, 1.75; 95% confidence interval, 1.04-2.96; P = 0.04). CONCLUSIONS: HFOV increases mortality for most patients with ARDS but may improve survival among patients with severe hypoxemia on conventional mechanical ventilation.

An Official American Thoracic Society/European Society of Intensive Care Medicine/Society of Critical Care Medicine Clinical Practice Guideline: Mechanical Ventilation in Adult Patients with Acute Respiratory Distress Syndrome.

BACKGROUND: This document provides evidence-based clinical practice guidelines on the use of mechanical ventilation in adult patients with acute respiratory distress syndrome (ARDS). METHODS: A multidisciplinary panel conducted systematic reviews and metaanalyses of the relevant research and applied Grading of Recommendations, Assessment, Development, and Evaluation methodology for clinical recommendations. RESULTS: For all patients with ARDS, the recommendation is strong for mechanical ventilation using lower tidal volumes (4-8 ml/kg predicted body weight) and lower inspiratory pressures (plateau pressure < 30 cm H2O) (moderate confidence in effect estimates). For patients with severe ARDS, the recommendation is strong for prone positioning for more than 12 h/d (moderate confidence in effect estimates). For patients with moderate or severe ARDS, the recommendation is strong against routine use of high-frequency oscillatory ventilation (high confidence in effect estimates) and conditional for higher positive end-expiratory pressure (moderate confidence in effect estimates) and recruitment maneuvers (low confidence in effect estimates). Additional evidence is necessary to make a definitive recommendation for or against the use of extracorporeal membrane oxygenation in patients with severe ARDS. CONCLUSIONS: The panel formulated and provided the rationale for recommendations on selected ventilatory interventions for adult patients with ARDS. Clinicians managing patients with ARDS should personalize decisions for their patients, particularly regarding the conditional recommendations in this guideline.