Stress Ulcer Prophylaxis during Invasive Mechanical Ventilation.

BACKGROUND: Whether proton-pump inhibitors are beneficial or harmful for stress ulcer prophylaxis in critically ill patients undergoing invasive ventilation is unclear. METHODS: In this international, randomized trial, we assigned critically ill adults who were undergoing invasive ventilation to receive intravenous pantoprazole (at a dose of 40 mg daily) or matching placebo. The primary efficacy outcome was clinically important upper gastrointestinal bleeding in the intensive care unit (ICU) at 90 days, and the primary safety outcome was death from any cause at 90 days. Multiplicity-adjusted secondary outcomes included ventilator-associated pneumonia, Clostridioides difficile infection, and patient-important bleeding. RESULTS: A total of 4821 patients underwent randomization in 68 ICUs. Clinically important upper gastrointestinal bleeding occurred in 25 of 2385 patients (1.0%) receiving pantoprazole and in 84 of 2377 patients (3.5%) receiving placebo (hazard ratio, 0.30; 95% confidence interval [CI], 0.19 to 0.47; P<0.001). At 90 days, death was reported in 696 of 2390 patients (29.1%) in the pantoprazole group and in 734 of 2379 patients (30.9%) in the placebo group (hazard ratio, 0.94; 95% CI, 0.85 to 1.04; P = 0.25). Patient-important bleeding was reduced with pantoprazole; all other secondary outcomes were similar in the two groups. CONCLUSIONS: Among patients undergoing invasive ventilation, pantoprazole resulted in a significantly lower risk of clinically important upper gastrointestinal bleeding than placebo, with no significant effect on mortality. (Funded by the Canadian Institutes of Health Research and others; REVISE ClinicalTrials.gov number, NCT03374800.).

Definitions, rates and associated mortality of ICU-acquired pneumonia: A multicenter cohort study.

INTRODUCTION: We aimed to analyze intensive care unit (ICU)-acquired pneumonia according to 7 definitions, estimating associated hospital mortality. METHODS: This cohort study was nested within an international randomized trial, evaluating the effect of probiotics on ICU-acquired pneumonia in 2650 mechanically ventilated adults. Each clinically suspected pneumonia was adjudicated by two physicians blinded to allocation and center. The primary outcome was ventilator-associated pneumonia (VAP) informed by ventilation for ≥2 days, new, progressive or persistent infiltrate plus 2 of: temperature > 38 °C or < 36 °C; leukopenia (<3 × 10(Fernando et al., 20206)/L) or leukocytosis (>10 × 10(Fernando et al., 20206)/L); and purulent sputum. We also used 6 other definitions estimating the risk of hospital mortality. RESULTS: The frequency of ICU-acquired pneumonia varied by definition: the trial primary outcome VAP (21.6%), Clinical Pulmonary Infection Score (CPIS) (24.9%), American College Chest Physicians (ACCP) (25.0%), International Sepsis Forum (ISF) (24.4%), Reducing Oxidative Stress Study (REDOXS) (17.6%), Centers for Disease Control (CDC) (7.8%), and invasively microbiologically confirmed (1.9%). The trial primary outcome VAP (HR 1.31 [1.08, 1.60]), ISF (HR 1.32 [1.09,1.60]), CPIS (HR 1.30 [1.08,1.58]) and ACCP definitions (HR 1.22 [1.00,1.47]) were associated with hospital mortality. CONCLUSIONS: Rates of ICU-acquired pneumonia vary by definition and are associated with differential increased risk of death.

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.).

Monitoring and auditing protocol adherence, data integrity and ethical conduct of a randomized clinical trial: A case study.

PURPOSE: To categorize, quantify and interpret findings documented in feedback letters of monitoring or auditing visits for an investigator-initiated, peer-review funded multicenter randomized trial testing probiotics for critically ill patients. MATERIALS & METHODS: In 37 Canadian centers, monitoring and auditing visits were performed by 3 trained individuals; findings were reported in feedback letters. At trial termination, we performed duplicate content analysis on letters, categorizing observations first into unique findings, followed by 10 pre-determined trial quality management domains. We further classified each observation into a) missing operational records, b) errors in process, and potential threats to c) data integrity, d) patient privacy or e) safety. RESULTS: Across 37 monitoring or auditing visits, 75 unique findings were categorized into 10 domains. Most frequently, observations were in domains of training documentation (180/566 [32%]) and the informed consent process (133/566 [23%]). Most observations were missing operational records (438/566 [77%]) rather than errors in process (128/566 [23%]). Of 75 findings, 13 (62/566 observations [11%]) posed a potential threat to data integrity, 1 (1/566 observation [0.18%]) to patient privacy, and 9 (49/566 observations [8.7%]) to patient safety. CONCLUSIONS: Monitoring and auditing findings predominantly concerned missing documentation with minimal threats to data integrity, patient privacy or safety. TRIAL REGISTRATION: PROSPECT (Probiotics: Prevention of Severe Pneumonia and Endotracheal Colonization Trial): NCT02462590.

Evolution of practice patterns in the management of acute respiratory distress syndrome: A secondary analysis of two successive randomized controlled trials.

PURPOSE: We sought to examine changes in acute respiratory distress syndrome (ARDS) management over a 12-year period of two successive randomized trials. METHODS: Analyses included baseline data, from eligible patients, prior to influence of trial protocols, and daily study data, from randomized patients, of variables not determined by trial protocols. Mixed linear regressions examined changes in practice year-on-year. RESULTS: A total of 2376 patients met the inclusion criteria. Over the 12-year period, baseline tidal volume index decreased (9.0 to 7.0 ml/kg, p < 0.001), plateau pressures decreased (30.8 to 29.0 cmH2O, p < 0.05), and baseline positive end-expiratory pressures increased (10.8 to 13.2 cmH2O, p < 0.001). Volume-controlled ventilation declined from 29.4 to 14.0% (p < 0.01). Use of corticosteroids increased (baseline: 7.7 to 30.3%; on study: 32.6 to 61.2%; both p < 0.001), as did neuromuscular blockade (baseline: 12.3 to 24.5%; on study: 55.5 to 70.0%; both p < 0.01). Inhaled nitric oxide use increased (24.9 to 65.8%, p < 0.05). We observed no significant change in prone positioning (16.2 to 18.9%, p = 0.70). CONCLUSIONS: Clear trends were apparent in tidal volume, airway pressures, ventilator modes, adjuncts and rescue therapies. With the exception of prone positioning, and outside the context of rescue therapy, these trends appear consistent with the evolving literature on ARDS management.

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.

Motivators and Stressors for Canadian Research Coordinators in Critical Care: The MOTIVATE Survey.

BACKGROUND: Critical care research coordinators implement study protocols in intensive care units, yet little is known about their experiences. OBJECTIVE: To identify the responsibilities, stressors, motivators, and job satisfaction of critical care research coordinators in Canada. METHODS: Responses to a self-administered survey were collected in order to identify and understand factors that motivate and stress research coordinators and enhance their job satisfaction. Items were generated in 5 domains (demographics, job responsibilities, stressors, motivators, and satisfaction). Face validity pretesting was conducted and clinical sensibility was evaluated. Items were rated on 5-point Likert scales. Descriptive analyses were used to report results. RESULTS: The response rate was 78% (66 of 85). Most critical care research coordinators (71%) were employed full time; they were engaged in 9 studies (7 academic, 2 industry); and 49% were nurses. Of 30 work responsibilities, the most frequently cited were submitting ethics applications (89%), performing data entry (89%), and attending meetings (87%). Highest-rated stressors were unrealistic workload and weekend/holiday screening; highest-rated motivators were a positive work environment and team spirit. Overall, 26% were "very satisfied" and 53% were "satisfied" with their jobs. CONCLUSIONS: Critical care research coordinators in Canada indicate that, despite significant work responsibilities, they are satisfied with their jobs thanks to positive work environments and team spirit.

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.

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.

Hamilton-DONATE: a city-wide pilot observational study of the ICU management of deceased organ donors.

PURPOSE: Improving the medical care of deceased organ donors to increase transplant rates and improve allograft function requires an understanding of the current epidemiology and clinical practices of deceased donation within intensive care units (ICUs). Herein, we report the results of our investigation into the feasibility of a multicentre prospective cohort study addressing the afformentioned issues. METHODS: We conducted a 12-month prospective observational cohort study in six ICUs and one coronary care unit in Hamilton, Canada. We included consecutive children and adults following consent for deceased organ donation (including neurologic determination of death [NDD] or donation after circulatory death [DCD]). Intensive care unit research staff recorded donor management data from hospital records, extending from one day prior to the consent for organ donation up to the time of organ retrieval. The provincial Organ Donation Organization (ODO) supplemented these data and, additionally, provided data on corresponding organ recipients. We identified, evaluated, and measured three potential obstacles to the feasibility of a national cohort study: obtaining authorization to implement the study with a waiver of research consent, accessibility of transplant recipient data, and the time required to complete very detailed case report forms (CRFs), with valuable lessons learned for implementation in future projects. RESULTS: The local Research Ethics Board and the ODO Privacy Office both authorized the recording of donor and recipient study data with a waiver of research consent. Sixty-seven consecutive consented donors were included (31 NDD and 36 DCD donors); 50 of them provided 144 organs for transplantation to 141 recipients. We identified the age and sex of the recipients as well as the location and date of transplant for all organ recipients in Ontario; however, we obtained no recipient data for six organs transported outside of Ontario. Intensive care unit research staff estimated that future CRF completion will require five to seven hours per patient. CONCLUSION: The Hamilton-DONATE pilot study supports the feasibility of a larger cohort study to describe the epidemiology and clinical practices related to deceased donor care in Canada. TRIAL REGISTRATION: wwwclinicaltrials.gov (NCT02902783). Registered 16 September 2016.

Canada-DONATE study protocol: a prospective national observational study of the medical management of deceased organ donors.

INTRODUCTION: Research on the management of deceased organ donors aims to improve the number and quality of transplants and recipient outcomes. In Canada, this research is challenged by regionalisation of donation services within provinces and the geographical, clinical and administrative separation of donation from transplantation services. This study aims to build a national platform for future clinical trials in donor management. Objectives are to engage collaborators at donation hospitals and organ donation organisations (ODOs) across Canada, describe current practices, evaluate the effectiveness of donation-specific interventions and assess the feasibility of future clinical trials. METHODS AND ANALYSIS: This ongoing prospective observational study of the medical management of deceased organ donors will enrol more than 650 consented potential donors from adult intensive care units at 33 hospital sites across Canada, each participating for 12 months. ODOs ensure enrolment of consecutive eligible participants. Research staff record detailed data about participants, therapies, organ assessments, death declaration procedures and adverse clinical exposures from the time of donation consent to organ recovery. ODOs provide reasons that organs are declined, dates and places of transplantation, and recipient age and sex.Descriptive analyses will summarise current practices. Effectiveness analyses will examine donation-specific interventions with respect to the number of transplants, using multilevel regression models to account for clustering by donor, hospitals and ODOs. Feasibility analyses will focus on acceptance of the research consent model; participation of academic and community hospitals as well as ODOs; and accessibility of recipient data. ETHICS AND DISSEMINATION: This study uses a waiver of research consent. Hospitals will receive reports on local practices benchmarked to (1) national practices and (2) national donor management guidelines. We will report findings to donation and transplant collaborators (ie, clinicians, researchers, ODOs) and publish in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03114436.

Management of Acute Respiratory Distress Syndrome and Refractory Hypoxemia. A Multicenter Observational Study.

RATIONALE: Clinicians' current practice patterns in the management of acute respiratory distress syndrome (ARDS) and refractory hypoxemia are not well described. OBJECTIVES: To describe mechanical ventilation strategies and treatment adjuncts for adults with ARDS, including refractory hypoxemia. METHODS: This was a prospective cohort study (March 2014-February 2015) of mechanically ventilated adults with moderate-to-severe ARDS requiring an FiO2 of 0.50 or greater in 24 intensive care units. RESULTS: We enrolled 664 patients: 222 (33%) with moderate and 442 (67%) with severe ARDS. On Study Day 1, mean Vt was 7.5 (SD = 2.1) ml/kg predicted body weight (n = 625); 80% (n = 501) received Vt greater than 6 ml/kg. Mean positive end-expiratory pressure (PEEP) was 10.5 (3.7) cm H2O (n = 653); 568 patients (87%) received PEEP less than 15 cm H2O. Treatment adjuncts were common (n = 440, 66%): neuromuscular blockers (n = 276, 42%), pulmonary vasodilators (n = 118, 18%), prone positioning (n = 67, 10%), extracorporeal life support (n = 29, 4%), and high-frequency oscillatory ventilation (n = 29, 4%). Refractory hypoxemia, defined as PaO2 less than 60 mm Hg on FiO2 of 1.0, occurred in 138 (21%) patients. At onset of refractory hypoxemia, mean Vt was 7.1 (SD = 2.0) ml/kg (n = 124); 95 patients (77%) received Vt greater than 6 ml/kg. Mean PEEP was 12.1 (SD = 4.4) cm H2O (n = 133); 99 patients (74%) received PEEP less than 15 cm H2O. Among patients with refractory hypoxemia, 91% received treatment adjuncts (126/138), with increased use of neuromuscular blockers (n = 87, 63%), pulmonary vasodilators (n = 57, 41%), and prone positioning (n = 32, 23%). CONCLUSIONS: Patients with moderate-to-severe ARDS receive treatment adjuncts frequently, especially with refractory hypoxemia. Paradoxically, therapies with less evidence supporting their use (e.g., pulmonary vasodilators) were over-used, whereas those with more evidence (e.g., prone positioning, neuromuscular blockade) were under-used. Patients received higher Vts and lower PEEP than would be suggested by the evidence.

Characteristics and Outcomes of Eligible Nonenrolled Patients in a Mechanical Ventilation Trial of Acute Respiratory Distress Syndrome.

RATIONALE: Patients eligible for randomized controlled trials may not be enrolled for various reasons. Nonenrollment may affect study generalizability and lengthen the time required for trial completion. OBJECTIVES: To describe characteristics and outcomes of eligible nonenrolled (ENE) patients in a multicenter trial of mechanical ventilation strategies. METHODS: Within the OSCILLATE trial of high-frequency oscillation (HFO) versus conventional ventilation (CV) in adults with adult respiratory distress syndrome, and with approval from research ethics boards, we collected a minimal dataset on patients who satisfied eligibility criteria but were not enrolled. We categorized ENE patients as ENE-HFO and ENE-CV based on receipt of HFO at any time. We used multivariable logistic regression to assess the association between ENE status and mortality. MEASUREMENTS AND MAIN RESULTS: A total of 548 patients were randomized, and 546 were ENE. The most common reasons for ENE were no consent (42%), physician refusal (24%), missed randomization window (15%), and current HFO use (14%). Compared with randomized patients in respective arms of the trial, ENE-HFO patients were younger and had worse lung injury, whereas ENE-CV patients had lower illness severity. ENE status was independently associated with mortality (adjusted odds ratio, 1.39; 95% confidence interval, 1.06-1.84; P = 0.02), with no significant interaction with ventilation treatment group. CONCLUSIONS: Nonenrollment was common, with approximately one ENE patient for every randomized patient. Our study suggests that enrollment in trials of mechanical ventilation may be associated with improved outcomes compared with standard care and highlights the need for prospective tracking and transparent reporting of ENE patients as part of trial management.

Coenrollment in a randomized trial of high-frequency oscillation: prevalence, patterns, predictors, and outcomes*.

OBJECTIVE: Enrollment of individual patients into more than one study has been poorly evaluated. The objective of this study was to describe the characteristics of patients, researchers and centers involved in coenrollment, studies precluding coenrollment, and the prevalence, patterns, predictors, and outcomes of coenrollment in a randomized clinical trial. DESIGN, SETTING, METHODS: We conducted an observational study nested within the OSCILLation for Acute Respiratory Distress Syndrome Treated Early Trial, which compared high-frequency oscillatory ventilation to conventional ventilation. We collected patient, center, and study data on coenrollment in randomized patients. Multilevel regression examined factors independently associated with coenrollment, considering clustering within centers. We examined the effect of coenrollment on safety and the trial outcome. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Overall, 127 of 548 randomized patients (23.2%) were coenrolled in 25 unique studies. Coenrollment was reported in 17 of 39 centers (43.6%). Patients were most commonly coenrolled in one additional randomized clinical trial (76; 59.8%). Coenrollment was less likely in older patients (odds ratio, 0.87; 95% CI, 0.76-0.997), and in ICUs with greater than 26 beds (odds ratio, 0.56; 95% CI, 0.34-0.94), and more likely by investigators with more than 11 years of experience (odds ratio, 1.73; 95% CI, 1.06-2.82), by research coordinators with more than 8 years of experience (odds ratio, 1.87; 95% CI, 1.11-3.18) and in Canada (odds ratio, 4.66; 95% CI, 1.43-15.15). Serious adverse events were similar between coenrolled high-frequency oscillatory ventilation and control patients. Coenrollment did not modify the treatment effect of high-frequency oscillatory ventilation on hospital mortality. CONCLUSIONS: Coenrollment occurred in 23% of patients, commonly in younger patients, in smaller centers with more research infrastructure, and in Canada. Coenrollment did not influence patient safety or trial results.

Wean earlier and automatically with new technology (the WEAN study). A multicenter, pilot randomized controlled trial.

RATIONALE: Automated weaning has not been compared with a paper-based weaning protocol in North America. OBJECTIVES: We conducted a pilot randomized trial comparing automated weaning with protocolized weaning in critically ill adults to evaluate clinician compliance and acceptance of the weaning and sedation protocols, recruitment, and impact on outcomes. METHODS: From August 2007 to October 2009, we enrolled critically ill adults requiring more than 24 hours of mechanical ventilation and at least partial reversal of the condition precipitating respiratory failure at nine Canadian intensive care units. We randomized patients who tolerated at least 30 minutes of pressure support and either failed or were not yet ready to undergo a spontaneous breathing trial to automated or protocolized weaning. Both groups used pressure support, included spontaneous breathing trials, used a common positive end-expiratory pressure-FI(O(2)) chart, sedation protocol, and criteria for extubation, reintubation, and noninvasive ventilation. MEASUREMENTS AND MAIN RESULTS: We recruited 92 patients (49 automated, 43 protocolized) over 26 months. Adherence to assigned weaning protocols and extreme sedation scale scores fell within prespecified thresholds. Combined physician-respiratory therapist and nurse acceptance scores of the study weaning and sedation protocols, respectively, were not significantly different. Automated weaning patients had significantly shorter median times to first successful spontaneous breathing trial (1.0 vs. 4.0 d; P < 0.0001), extubation (3.0 vs. 4.0 d; P = 0.02), and successful extubation (4.0 vs. 5.0 d; P = 0.01), and underwent fewer tracheostomies and episodes of protracted ventilation. CONCLUSIONS: Compared with a standardized protocol, automated weaning was associated with promising outcomes that warrant further investigation. Minor protocol modifications may increase compliance, facilitate recruitment, and enhance feasibility. Clinical trial registered with www.controlled-trials.com (ISRCTN43760151).

High-frequency oscillation in early acute respiratory distress syndrome.

BACKGROUND: Previous trials suggesting that high-frequency oscillatory ventilation (HFOV) reduced mortality among adults with the acute respiratory distress syndrome (ARDS) were limited by the use of outdated comparator ventilation strategies and small sample sizes. METHODS: In a multicenter, randomized, controlled trial conducted at 39 intensive care units in five countries, we randomly assigned adults with new-onset, moderate-to-severe ARDS to HFOV targeting lung recruitment or to a control ventilation strategy targeting lung recruitment with the use of low tidal volumes and high positive end-expiratory pressure. The primary outcome was the rate of in-hospital death from any cause. RESULTS: On the recommendation of the data monitoring committee, we stopped the trial after 548 of a planned 1200 patients had undergone randomization. The two study groups were well matched at baseline. The HFOV group underwent HFOV for a median of 3 days (interquartile range, 2 to 8); in addition, 34 of 273 patients (12%) in the control group received HFOV for refractory hypoxemia. In-hospital mortality was 47% in the HFOV group, as compared with 35% in the control group (relative risk of death with HFOV, 1.33; 95% confidence interval, 1.09 to 1.64; P=0.005). This finding was independent of baseline abnormalities in oxygenation or respiratory compliance. Patients in the HFOV group received higher doses of midazolam than did patients in the control group (199 mg per day [interquartile range, 100 to 382] vs. 141 mg per day [interquartile range, 68 to 240], P<0.001), and more patients in the HFOV group than in the control group received neuromuscular blockers (83% vs. 68%, P<0.001). In addition, more patients in the HFOV group received vasoactive drugs (91% vs. 84%, P=0.01) and received them for a longer period than did patients in the control group (5 days vs. 3 days, P=0.01). CONCLUSIONS: In adults with moderate-to-severe ARDS, early application of HFOV, as compared with a ventilation strategy of low tidal volume and high positive end-expiratory pressure, does not reduce, and may increase, in-hospital mortality. (Funded by the Canadian Institutes of Health Research; Current Controlled Trials numbers, ISRCTN42992782 and ISRCTN87124254, and ClinicalTrials.gov numbers, NCT00474656 and NCT01506401.).

High-frequency oscillation in adults: a utilization review.

OBJECTIVES: High-frequency oscillation is used for adults with acute lung injury/acute respiratory distress syndrome. Given the uncertain benefits, our objective was to describe contemporary patient selection, high-frequency oscillation utilization, and outcomes. DESIGN: Utilization review. SETTING: Ten academic centers (Ontario, Canada; January 1, 2005-January 31, 2007). PATIENTS: We included 190 consecutive adults treated with high-frequency oscillation and retrospectively abstracted data on patient demographics, gas exchange, hemodynamics, settings during conventional ventilation and high-frequency oscillation, adjunctive therapies, and outcomes. We used logistic regression to explore associations with oxygenation response and hemodynamic and ventilatory complications (2 hrs after high-frequency oscillation initiation) and mortality. Continuous data are reported as mean (sd) or median (quartile 1, quartile 3). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients (60.0% male; mean age, 52; sd 17) had predominantly acute lung injury/acute respiratory distress syndrome (89.8%) and were severely ill (mean Acute Physiology and Chronic Health Evaluation II score, 28; sd, 9) and hypoxemic (mean Pao2/Fio2, 80; sd, 42). High-frequency oscillation was started a median of 2 (1, 8) days after intubation and continued for a median of 3 (2, 7) days. During high-frequency oscillation, adjunctive treatments (neuromuscular blockade, 75.6%; recruitment maneuvers, 49.5%; nitric oxide, 34.0%; steroids, 63.1%) and new barotrauma or chest tube placement (23.5%) were common. Ten patients (5.3%) had technical complications; five required a new ventilator. Reasons for stopping high-frequency oscillation included death or withdrawal of life support (39.1%), significant improvement in respiratory failure (37.6%), and inadequate improvement (23.3%). One hundred and twenty-eight of 189 patients died in hospital. Most (62.5%) had a positive oxygenation response after 2 hrs of high-frequency oscillation (mean absolute increase in PaO2/FiO2, 22 [SD, 54]; 95% confidence interval of mean 14-31). A minority had lower PaO2/FiO2 (32.5%) or a hemodynamic (27.5%) or ventilatory (30.5%) complication. Older age, Acute Physiology and Chronic Health Evaluation II score, and Paco2 before high-frequency oscillation were independently associated with mortality. CONCLUSIONS: Most patients treated with high-frequency oscillation have acute respiratory distress syndrome and severe hypoxemia that modestly improves 2 hrs after high-frequency oscillation application. However, oxygenation worsens in some patients, complications are common, and mortality is high.

A study of the physiologic responses to a lung recruitment maneuver in acute lung injury and acute respiratory distress syndrome.

OBJECTIVE: To determine the magnitude, duration, and consistency of the effects of lung recruitment maneuvers (RMs) on oxygenation, lung mechanics, and comfort in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). METHODS: We conducted a prospective physiologic study at 3 tertiary-care hospitals. We enrolled 28 consecutive eligible patients with ARDS or ALI and a ratio of P(aO(2)) to fraction of inspired oxygen (P(aO(2))/F(IO(2))) or= 0.50. We performed RMs twice daily for 3 days. The first RM was at 35 cm H(2)O for 20 s. If initial response was equivocal, the clinician immediately administered another RM at a higher pressure (40 cm H(2)O, then 45 cm H(2)O) or for longer period (30 s, then 40 s), in a randomized order. Each patient had up to 6 sets of up to 3 RMs. RESULTS: Twenty-seven patients met the criteria for ARDS at baseline; 1 had ALI. There was no net effect on oxygenation or pulmonary mechanics following the first or subsequent RMs. The largest rise in P(aO(2)) was from 61 mm Hg to 71 mm Hg, and the largest decrease was 6 mm Hg following the first RM. Augmenting the inflation pressure or duration had no significant effect. These findings precluded analyses about predictors of response or consistency of response. Over the entire study of 122 RMs, 5 patients developed ventilator asynchrony, 3 appeared uncomfortable, 2 experienced transient hypotension, and 4 developed barotrauma that required intervention. CONCLUSIONS: These results do not support the addition of scheduled RMs to usual treatment for ALI or ARDS.