Protocol implementation during the COVID-19 pandemic: experiences from a randomized trial of stress ulcer prophylaxis.

BACKGROUND: During the COVID-19 pandemic, many intensive care units (ICUs) halted research to focus on COVID-19-specific studies. OBJECTIVE: To describe the conduct of an international randomized trial of stress ulcer prophylaxis (Re-Evaluating the Inhibition of Stress Erosions in the ICU [REVISE]) during the pandemic, addressing enrolment patterns, center engagement, informed consent processes, data collection, a COVID-specific substudy, patient transfers, and data monitoring. METHODS: REVISE is a randomized trial among mechanically ventilated patients, comparing pantoprazole 40 mg IV to placebo on the primary efficacy outcome of clinically important upper gastrointestinal bleeding and the primary safety outcome of 90-day mortality. We documented protocol implementation status from March 11th 2020-August 30th 2022. RESULTS: The Steering Committee did not change the scientific protocol. From the first enrolment on July 9th 2019 to March 10th 2020 (8 months preceding the pandemic), 267 patients were enrolled in 18 centers. From March 11th 2020-August 30th 2022 (30 months thereafter), 41 new centers joined; 59 were participating by August 30th 2022 which enrolled 2961 patients. During a total of 1235 enrolment-months in the pandemic phase, enrolment paused for 106 (8.6%) months in aggregate (median 3 months, interquartile range 2;6). Protocol implementation involved a shift from the a priori consent model pre-pandemic (188, 58.8%) to the consent to continue model (1615, 54.1%, p < 0.01). In one new center, an opt-out model was approved. The informed consent rate increased slightly (80.7% to 85.0%, p = 0.05). Telephone consent encounters increased (16.6% to 68.2%, p < 0.001). Surge capacity necessitated intra-institutional transfers; receiving centers continued protocol implementation whenever possible. We developed a nested COVID-19 substudy. The Methods Centers continued central statistical monitoring of trial metrics. Site monitoring was initially remote, then in-person when restrictions lifted. CONCLUSION: Protocol implementation adaptations during the pandemic included a shift in the consent model, a sustained high consent rate, and launch of a COVID-19 substudy. Recruitment increased as new centers joined, patient transfers were optimized, and monitoring methods were adapted.

Adjudication of a primary trial outcome: Results of a calibration exercise and protocol for a large international trial.

Background: Ascertainment of the severity of the primary outcome of upper gastrointestinal (GI) bleeding is integral to stress ulcer prophylaxis trials. This protocol outlines the adjudication process for GI bleeding events in an international trial comparing pantoprazole to placebo in critically ill patients (REVISE: Re-Evaluating the Inhibition of Stress Erosions). The primary objective of the adjudication process is to assess episodes submitted by participating sites to determine which fulfil the definition of the primary efficacy outcome of clinically important upper GI bleeding. Secondary objectives are to categorize the bleeding severity if deemed not clinically important, and adjudicate the bleeding site, timing, investigations, and treatments. Methods: Research coordinators follow patients daily for any suspected clinically important upper GI bleeding, and submit case report forms, doctors' and nurses' notes, laboratory, imaging, and procedural reports to the methods center. An international central adjudication committee reflecting diverse specialty backgrounds conducted an initial calibration exercise to delineate the scope of the adjudication process, review components of the definition, and agree on how each criterion will be considered fulfilled. Henceforth, bleeding events will be stratified by study drug, and randomly assigned to adjudicator pairs (blinded to treatment allocation, and study center). Results: Crude agreement, chance-corrected agreement, or chance-independent agreement if data have a skewed distribution will be calculated. Conclusions: Focusing on consistency and accuracy, central independent blinded duplicate adjudication of suspected clinically important upper GI bleeding events will determine which events fulfil the definition of the primary efficacy outcome for this stress ulcer prophylaxis trial. Registration: NCT03374800 (REVISE: Re-Evaluating the Inhibition of Stress Erosions).

Proton pump inhibitors for gastrointestinal bleeding prophylaxis in critically ill patients: A systematic review protocol.

BACKGROUND: Proton pump inhibitors (PPIs) are the most commonly prescribed drugs for preventing upper gastrointestinal bleeding in critically ill patients. However, concerns have arisen about the possible harms of using PPIs, including potentially increased risk of pneumonia, Clostridioides difficile infection, and more seriously, an increased risk of death in the most severely ill patients. Triggered by the REVISE trial, which is a forthcoming large randomized trial comparing pantoprazole to placebo in invasively mechanically ventilated patients, we will conduct this systematic review to evaluate the efficacy and safety of PPIs versus no prophylaxis for critically ill patients. METHODS: We will systematically search randomized trials that compared gastrointestinal bleeding prophylaxis with PPIs versus placebo or no prophylaxis in adults in the intensive care unit (ICU). Pairs of reviewers will independently screen the literature, and for those eligible trials, extract data and assess risk of bias. We will perform meta-analyses using a random-effects model, and calculate relative risks for dichotomous outcomes and mean differences for continuous outcomes, and the associated 95% confidence intervals. We will conduct subgroup analysis to explore whether the impact of PPIs on mortality differs in more and less severely ill patients. We will assess certainty of evidence using the GRADE approach. DISCUSSION: This systematic review will provide the most up-to-date evidence regarding the merits and limitations of stress ulcer prophylaxis with PPIs in critically ill patients in contemporary practice.

A Randomized Noninferiority Trial to Compare Enteral to Parenteral Phosphate Replacement on Biochemistry, Waste, and Environmental Impact and Healthcare Cost in Critically Ill Patients With Mild to Moderate Hypophosphatemia.

OBJECTIVES: Hypophosphatemia occurs frequently. Enteral, rather than IV, phosphate replacement may reduce fluid replacement, cost, and waste. DESIGN: Prospective, randomized, parallel group, noninferiority clinical trial. SETTING: Single center, 42-bed state trauma, medical and surgical ICUs, from April 20, 2022, to July 1, 2022. PATIENTS: Patients with serum phosphate concentration between 0.3 and 0.75 mmol/L. INTERVENTIONS: We randomized patients to either enteral or IV phosphate replacement using electronic medical record-embedded program. MEASUREMENT AND MAIN RESULTS: Our primary outcome was serum phosphate at 24 hours with a noninferiority margin of 0.2 mmol/L. Secondary outcomes included cost savings and environmental waste reduction and additional IV fluid administered. The modified intention-to-treat cohort comprised 131 patients. Baseline phosphate concentrations were similar between the two groups. At 24 hours, mean (sd) serum phosphate concentration were enteral 0.89 mmol/L (0.24 mmol/L) and IV 0.82 mmol/L (0.28 mmol/L). This difference was noninferior at the margin of 0.2 mmol/L (difference, 0.07 mmol/L; 95% CI, -0.02 to 0.17 mmol/L). When assigned IV replacement, patients received 408 mL (372 mL) of solvent IV fluid. Compared with IV replacement, the mean cost per patient was ten-fold less with enteral replacement ($3.7 [$4.0] vs. IV: $37.7 [$31.4]; difference = $34.0 [95% CI, $26.3-$41.7]) and weight of waste was less (7.7 g [8.3 g] vs. 217 g [169 g]; difference = 209 g [95% CI, 168-250 g]). CO2 emissions were 60-fold less for comparable phosphate replacement (enteral: 2 g producing 14.2 g and 20 mmol of potassium dihydrogen phosphate producing 843 g of CO2 equivalents). CONCLUSIONS: Enteral phosphate replacement in ICU is noninferior to IV replacement at a margin of 0.2 mmol/L but leads to a substantial reduction in cost and waste.

Association between protocol change to a higher-protein formula with lower energy targets and nutrient delivery in critically ill patients with COVID-19: A retrospective cohort study.

BACKGROUND: Guidelines recommend prioritizing protein provision while avoiding excessive energy delivery to critically ill patients with coronavirus disease 2019 (COVID-19), but there are no prospective studies evaluating such a targeted approach in this group. We aimed to evaluate the effect of a "higher-protein formula protocol" on protein, energy, and volume delivery when compared with standard nutrition protocol. METHODS: This was a retrospective cohort study of adult patients with COVID-19 who received mechanical ventilation for >72 h and enteral nutrition. Before October 2021, the standard nutrition protocol for patients was 0.7 ml/kg/h ideal body weight (IBW) of a 63 g/L protein and 1250 kcal/L formula. From October 2021, we implemented a higher-protein formula protocol for patients with COVID-19. The initial prescription was 0.5 ml/kg/h IBW of a 100 g/L protein and 1260 kcal/L formula with greater emphasis on energy targets being directed by indirect calorimetry when possible. Measured outcomes included protein, energy, and volume delivered. RESULTS: There were 114 participants (standard protocol, 48; higher-protein protocol, 66) with 1324 days of nutrition support. The median (95% CI) differences in protein, energy, and volume delivery between targeted and standard protocol periods were 0.08 g/kg/day (-0.02 to 0.18 g/kg/day), -1.71 kcal/kg/day (-3.64 to 0.21 kcal/kg/day) and -1.5 ml/kg/day (-2.9 to -0.1 ml/kg/day). Thirty-three patients (standard protocol, 7; higher-protein protocol, 26) had 44 indirect calorimetry assessments. There was no difference in measured energy expenditure over time (increased by 0.49 kcal/kg/day [-0.89 to 1.88 kcal/kg/day]). CONCLUSION: Implementation of a higher-protein formula protocol to patients with COVID-19 modestly reduced volume administration without impacting protein and energy delivery.

Plasma beta-hydroxy-beta-methylbutyrate availability after enteral administration during critical illness after trauma: An exploratory study.

BACKGROUND: During critical illness skeletal muscle wasting occurs rapidly. Although beta-hydroxy-beta-methylbutyrate (HMB) is a potential treatment to attenuate this process, the plasma appearance and muscle concentration is uncertain. METHODS: This was an exploratory study nested within a blinded, parallel group, randomized clinical trial in which critically ill patients after trauma received enteral HMB (3 g daily) or placebo. Plasma samples were collected at 0, 60, and 180 min after study supplement administration on day 1. Needle biopsies of the vastus lateralis muscle were collected (baseline and day 7 of the HMB treatment intervention period). An external standard curve was used to calculate HMB concentrations in plasma and muscle. RESULTS: Data were available for 16 participants (male n = 12 (75%), median [interquartile range] age 50 [29-58] years) who received placebo and 18 participants (male n = 14 (78%), age 49 [34-55] years) who received HMB. Plasma HMB concentrations were similar at baseline but increased after HMB (T = 60 min: placebo 0.60 [0.44-1.31] µM; intervention 51.65 [22.76-64.72] µM). Paired muscle biopsies were collected from 11 participants (placebo n = 7, HMB n = 4). Muscle HMB concentrations were similar at baseline between groups (2.35 [2.17-2.95]; 2.07 [1.78-2.31] µM). For participants in the intervention group who had the repeat biopsy within 4 h of HMB administration, concentrations were greater (7.2 and 12.3 µM) than those who had the repeat biopsy >4 h after HMB (2.7 and 2.1 µM). CONCLUSION: In this exploratory study, enteral HMB administration increased plasma HMB availability. The small sample size limits interpretation of the muscle HMB findings.

Patient-important upper gastrointestinal bleeding in the ICU: A mixed-methods study of patient and family perspectives.

INTRODUCTION: The objective of this study was to create a definition of patient-important upper gastrointestinal bleeding during critical illness as an outcome for a randomized trial. DESIGN: This was a sequential mixed-methods qualitative-dominant multi-center study with an instrument-building aim. In semi-structured individual interviews or focus groups we elicited views from survivors of critical illness and family members of patients in the intensive care unit (ICU) regarding which features indicate important gastrointestinal bleeding. Quantitative demographic characteristics were collected. We analyzed qualitative data using inductive content analysis to develop a definition for patient-important upper gastrointestinal bleeding. SETTING: Canada and the United States. PARTICIPANTS: 51 ICU survivors and family members of ICU patients. RESULTS: Participants considered gastrointestinal bleeding to be important if it resulted in death, disability, or prolonged hospitalization. The following also signaled patient-important upper gastrointestinal bleeding: blood transfusion, vasopressors, endoscopy, CT-angiography, or surgery. Whether an intervention evinced concern depended on its effectiveness, side-effects, invasiveness and accessibility; contextual influences included participant familiarity and knowledge of interventions and trust in the clinical team. CONCLUSIONS: Survivors of critical illness and family members described patient-important upper gastrointestinal bleeding differently than current definitions of clinically-important upper gastrointestinal bleeding.

Clinician- and Patient-Identified Solutions to Reduce the Fragmentation of Post-ICU Care in Australia.

BACKGROUND: Critical care survivors experience multiple care transitions, with no formal follow-up care pathway. RESEARCH QUESTION: What are the potential solutions to improve the communication between treating teams and integration of care following an ICU admission, from the perspective of patients, their caregivers, intensivists, and general practitioners (GPs) from diverse socioeconomic areas? STUDY DESIGN AND METHODS: This study included a qualitative design using semi-structured interviews with intensivists, GPs, and patients and caregivers. Framework analysis was used to analyze data and to identify solutions to improve the integration of care following hospital discharge. Patients were previously mechanically ventilated for > 24 h in the ICU and had access to a video-enabled device. Clinicians were recruited from hospital networks and a state-wide GP network. RESULTS: Forty-six interviews with clinicians, patients, and caregivers were completed (15 intensivists, 8 GPs, 15 patients, and 8 caregivers). Three higher level feedback loops were identified that comprised 10 themes. Feedback loop 1 was an ICU and primary care collaboration. It included the following: (1) developing collaborative relationships between the ICU and primary care; (2) providing interprofessional education and resources to support primary care; and (3) improving role clarity for patient follow-up care. Feedback loop 2 was developing mechanisms for improved communication across the care continuum. It included: (4) timely, concise information-sharing with primary care on post-ICU recovery; (5) survivorship-focused information-sharing across the continuum of care; (6) empowering patients and caregivers in self-management; and (7) creation of a care coordinator role for survivors. Feedback loop 3 was learning from post-ICU outcomes to improve future care. It included: (8) developing comprehensive post-ICU care pathways; (9) enhancing support for patients following a hospital stay; and (10) integration of post-ICU outcomes within the ICU to improve clinician morale and understanding. INTERPRETATION: Practical solutions to enhance the quality of survivorship for critical care survivors and their caregivers were identified. These themes are mapped to a novel conceptual model that includes key feedback loops for health system improvements and foci for future interventional trials to improve ICU survivorship outcomes.

In-person peer support for critical care survivors: The ICU REcovery Solutions cO-Led through surVivor Engagement (ICURESOLVE) pilot randomised controlled trial.

BACKGROUND: Peer support is a promising intervention to mitigate post-ICU disability, however there is a paucity of rigorously designed studies. OBJECTIVES: The objective of this study was to establish feasibility of an in-person, co-designed, peer-support model. METHODS: Prospective, randomised, adaptive, single-centre pilot trial with blinded outcome assessment, conducted at a university-affiliated hospital in Melbourne, Australia. Intensive care unit survivors (and their nominated caregiver, where survivor and caregiver are referred to as a dyad), >18 years of age, able to speak and understand English and participate in phone surveys, were eligible. Participants were randomised to the peer-support model (six sessions, fortnightly) or usual care (no follow-up or targeted information). Two sequential models were piloted: 1. Early (2-3 weeks post hospital discharge) 2. Later (4-6 weeks post hospital discharge). Primary outcome was feasibility of implementation measured by recruitment, intervention attendance, and outcome completion. Secondary outcomes included post-traumatic stress and social support. RESULTS: Of the 231 eligible patients, 80 participants were recruited. In the early model we recruited 38 participants (28 patients, 10 carers; 18 singles, 10 dyads), with an average (standard deviation) age of 60 (18) years; 55 % were female. Twenty-two participants (58 %) were randomised to intervention. Participants in the early intervention model attended a median (interquartile range) of 0 (0-1) sessions (total 24 sessions), with 53% (n = 20) completing the main secondary outcome of interest (Impact of Event Scale) at the baseline and 37 % (n = 14) at the follow-up. For the later model we recruited 42 participants (32 patients, 10 carers; 22 singles, 10 dyads), with an average (standard deviation) age of 60.4 (15.4) years; 50 % were female. Twenty-one participants (50 %) were randomised to intervention. The later intervention model attended a median (interquartile range) of 1 (0-5) sessions (total: 44 sessions), with the main secondary outcome impact of events scale (IES-R) completed by 41 (98 %) participants at baseline and 29 (69 %) at follow-up. CONCLUSIONS: In this pilot trial, a peer-support model that required in-person attendance delivered in a later posthospital phase of recovery appeared more feasible than an early model. Further research should investigate alternative modes of intervention delivery to improve feasibility (ACTRN12621000737831).

Feasibility of Embedding a Randomised Clinical Trial (RCT) into an Electronic Medical Record (EMR) for Patients Admitted to an Intensive Care Unit (ICU).

To establish the feasibility of embedding an RCT into EMR in the ICU, we evaluated the route of phosphate replacement. The EMR screened 207 patients who met the inclusion criteria from 20 April 2022 to 30 June 2022. 162 patients were randomised and 145 patients allocated to treatment. Our study showed that it was feasible to embed screening, randomisation, and treatment allocation for an RCT within an EMR in the ICU.

Perioperative management of long-acting glucagon-like peptide-1 (GLP-1) receptor agonists: concerns for delayed gastric emptying and pulmonary aspiration.

Prescriptions and use of glucagon-like peptide-1 (GLP-1) receptor agonists are increasing dramatically, as indications are expanding from the treatment of diabetes mellitus to weight loss for people with obesity. As GLP-1 receptor agonists delay gastric emptying, perioperative healthcare practitioners could be concerned about an increased risk for pulmonary aspiration during general anaesthesia. We summarise relevant medical literature and provide evidence-based recommendations for perioperative care for people taking GLP-1 receptor agonists. GLP-1 receptor agonists delay gastric emptying; however, ongoing treatment attenuates this effect. The risk of aspiration during general anaesthesia is unknown. However, we advise caution in patients who recently commenced on GLP-1 receptor agonists. After over 12 weeks of treatment, standard fasting times likely suffice to manage the risk of pulmonary aspiration for most otherwise low-risk patients.

Models of intensive care unit follow-up care and feasibility of intervention delivery: A systematic review.

BACKGROUND: The optimal model of outpatient intensive care unit (ICU) follow-up care remains uncertain, and there is limited evidence of benefit. RESEARCH QUESTION: The objective of this research is to describe existing models of outpatient ICU follow-up care, quantify participant recruitment and retention, and describe facilitators of patient engagement. STUDY DESIGN & METHODS: A systematic search of the MEDLINE and EMBASE databases was undertaken in June 2021. Two independent reviewers screened titles, abstracts, and full texts against eligibility criteria. Studies of adults with any outpatient ICU follow-up were included. Studies were excluded if published before 1990, not published in English, or of paediatric patients. Quantitative data were extracted using predefined data fields. Key themes were extracted from qualitative studies. Risk of bias was assessed. RESULTS: A total of 531 studies were screened. Forty-seven studies (32 quantitative and 15 qualitative studies) with a total of 5998 participants were included. Of 33 quantitative study interventions, the most frequently reported model of care was in-person hospital-based interventions (n = 27), with 10 hybrid (part in-hospital, part remote) interventions. Literature was limited for interventions without hospital attendance (n = 6), including telehealth and diaries. The median ranges of rates of recruitment, rates of intervention delivery, and retention to outcome assessment for hospital-based interventions were 51.5% [24-94%], 61.9% [8-100%], and 52% [8.1-82%], respectively. Rates were higher for interventions without hospital attendance: 82.6% [60-100%], 68.5% [59-89%], and 75% [54-100%]. Facilitators of engagement included patient-perceived value of follow-up, continuity of care, intervention accessibility and flexibility, and follow-up design. Studies had a moderate risk of bias. INTERPRETATION: Models of post-ICU care without in-person attendance at the index hospital potentially have higher rates of recruitment, intervention delivery success, and increased participant retention when compared to hospital-based interventions. PROSPERO REGISTRATION: CRD42021260279.

REVISE: re-evaluating the inhibition of stress erosions in the ICU-statistical analysis plan for a randomized trial.

BACKGROUND: The REVISE (Re-Evaluating the Inhibition of Stress Erosions in the ICU) trial will evaluate the impact of the proton pump inhibitor pantoprazole compared to placebo in invasively ventilated critically ill patients. OBJECTIVE: To outline the statistical analysis plan for the REVISE trial. METHODS: REVISE is a randomized clinical trial ongoing in intensive care units (ICUs) internationally. Patients ≥ 18 years old, receiving invasive mechanical ventilation, and expected to remain ventilated beyond the calendar day after randomization are allocated to either 40 mg pantoprazole intravenously or placebo while mechanically ventilated. RESULTS: The primary efficacy outcome is clinically important upper GI bleeding; the primary safety outcome is 90-day mortality. Secondary outcomes are ventilator-associated pneumonia, Clostridioides difficile infection, new renal replacement therapy, ICU and hospital mortality, and patient-important GI bleeding. Tertiary outcomes are total red blood cells transfused, peak serum creatinine concentration, and duration of mechanical ventilation, ICU, and hospital length of stay. Following an interim analysis of results from 2400 patients (50% of 4800 target sample size), the data monitoring committee recommended continuing enrolment. CONCLUSIONS: This statistical analysis plan outlines the statistical analyses of all outcomes, sensitivity analyses, and subgroup analyses. REVISE will inform clinical practice and guidelines worldwide. TRIAL REGISTRATION: www. CLINICALTRIALS: gov NCT03374800. November 21, 2017.

Angiotensin II treatment is associated with improved oxygenation in ARDS patients with refractory vasodilatory shock.

BACKGROUND: The physiological effects of renin-angiotensin system modulation in acute respiratory distress syndrome (ARDS) remain controversial and have not been investigated in randomized trials. We sought to determine whether angiotensin-II treatment is associated with improved oxygenation in shock-associated ARDS. METHODS: Post-hoc subgroup analysis of the Angiotensin Therapy for High Output Shock (ATHOS-3) trial. We studied patients who met modified Berlin ARDS criteria at enrollment. The primary outcome was PaO2/FiO2-ratio (P:F) at 48-h adjusted for baseline P:F. Secondary outcomes included oxygenation index, ventilatory ratio, PEEP, minute-ventilation, hemodynamic measures, patients alive and ventilator-free by day-7, and mortality. RESULTS: Of 81 ARDS patients, 34 (42%) and 47 (58%) were randomized to angiotensin-II or placebo, respectively. In angiotensin-II patients, mean P:F increased from 155 mmHg (SD: 69) at baseline to 265 mmHg (SD: 160) at hour-48 compared with no change with placebo (148 mmHg (SD: 63) at baseline versus 164 mmHg (SD: 74) at hour-48)(baseline-adjusted difference: + 98.4 mmHg [95%CI 35.2-161.5], p = 0.0028). Similarly, oxygenation index decreased by - 6.0 cmH2O/mmHg at hour-48 with angiotensin-II versus - 0.4 cmH2O/mmHg with placebo (baseline-adjusted difference: -4.8 cmH2O/mmHg, [95%CI - 8.6 to - 1.1], p = 0.0273). There was no difference in PEEP, minute ventilation, or ventilatory ratio. Twenty-two (64.7%) angiotensin-II patients had sustained hemodynamic response to treatment at hour-3 versus 17 (36.2%) placebo patients (absolute risk-difference: 28.5% [95%CI 6.5-47.0%], p = 0.0120). At day-7, 7/34 (20.6%) angiotensin-II patients were alive and ventilator-free versus 5/47(10.6%) placebo patients. Day-28 mortality was 55.9% in the angiotensin-II group versus 68.1% in the placebo group. CONCLUSIONS: In post-hoc analysis of the ATHOS-3 trial, angiotensin-II was associated with improved oxygenation versus placebo among patients with ARDS and catecholamine-refractory vasodilatory shock. These findings provide a physiologic rationale for trials of angiotensin-II as treatment for ARDS with vasodilatory shock. TRIAL REGISTRATION: ClinicalTrials.Gov Identifier: NCT02338843 (Registered January 14th 2015).

REVISE: Re-Evaluating the Inhibition of Stress Erosions in the ICU: a randomised trial protocol.

INTRODUCTION: The Re-Evaluating the Inhibition of Stress Erosions (REVISE) Trial aims to determine the impact of the proton pump inhibitor pantoprazole compared with placebo on clinically important upper gastrointestinal (GI) bleeding in the intensive care unit (ICU), 90-day mortality and other endpoints in critically ill adults. The objective of this report is to describe the rationale, methodology, ethics and management of REVISE. METHODS AND ANALYSIS: REVISE is an international, randomised, concealed, stratified, blinded parallel-group individual patient trial being conducted in ICUs in Canada, Australia, Saudi Arabia, UK, US, Kuwait, Pakistan and Brazil. Patients≥18 years old expected to remain invasively mechanically ventilated beyond the calendar day after enrolment are being randomised to either 40 mg pantoprazole intravenously or an identical placebo daily while mechanically ventilated in the ICU. The primary efficacy outcome is clinically important upper GI bleeding within 90 days of randomisation. The primary safety outcome is 90-day all-cause mortality. Secondary outcomes include rates of ventilator-associated pneumonia, Clostridioides difficile infection, new renal replacement therapy, ICU and hospital mortality, and patient-important GI bleeding. Tertiary outcomes are total red blood cells transfused, peak serum creatinine level in the ICU, and duration of mechanical ventilation, ICU and hospital stay. The sample size is 4800 patients; one interim analysis was conducted after 2400 patients had complete 90-day follow-up; the Data Monitoring Committee recommended continuing the trial. ETHICS AND DISSEMINATION: All participating centres receive research ethics approval before initiation by hospital, region or country, including, but not limited to - Australia: Northern Sydney Local Health District Human Research Ethics Committee and Mater Misericordiae Ltd Human Research Ethics Committee; Brazil: Comissão Nacional de Ética em Pesquisa; Canada: Hamilton Integrated Research Ethics Board; Kuwait: Ministry of Health Standing Committee for Coordination of Health and Medical Research; Pakistan: Maroof Institutional Review Board; Saudi Arabia: Ministry of National Guard Health Affairs Institutional Review Board: United Kingdom: Hampshire B Research Ethics Committee; United States: Institutional Review Board of the Nebraska Medical Centre. The results of this trial will inform clinical practice and guidelines worldwide. TRIAL REGISTRATION NUMBER: NCT03374800.

Protocol summary and statistical analysis plan for the low oxygen intervention for cardiac arrest injury limitation (LOGICAL) trial.

Background: The effect of conservative vs. liberal oxygen therapy on outcomes of intensive care unit (ICU) patients with hypoxic ischaemic encephalopathy (HIE) is uncertain and will be evaluated in the Low Oxygen Intervention for Cardiac Arrest injury Limitation (LOGICAL) trial. Objective: The objective of this study was to summarise the protocol and statistical analysis plans for the LOGICAL trial. Design setting and participants: LOGICAL is a randomised clinical trial in adults in the ICU who are comatose with suspected HIE (i.e., those who have not obeyed commands following return of spontaneous circulation after a cardiac arrest where there is clinical concern about possible brain damage). The LOGICAL trial will include 1400 participants and is being conducted as a substudy of the Mega Randomised registry trial comparing conservative vs. liberal oxygenation targets in adults receiving unplanned invasive mechanical ventilation in the ICU (Mega-ROX). Main outcome measures: The primary outcome is survival with favourable neurological function at 180 days after randomisation as measured with the Extended Glasgow Outcome Scale (GOS-E). A favourable neurological outcome will be defined as a GOS-E score of lower moderate disability or better (i.e. a GOS-E score of 5-8). Secondary outcomes include survival time, day 180 mortality, duration of invasive mechanical ventilation, ICU length of stay, hospital length of stay, the proportion of patients discharged home, quality of life assessed at day 180 using the EQ-5D-5L, and cognitive function assessed at day 180 using the Montreal Cognitive Assessment (MoCA-blind). Conclusions: The LOGICAL trial will provide reliable data on the impact of conservative vs. liberal oxygen therapy in ICU patients with suspected HIE following resuscitation from a cardiac arrest. Prepublication of the LOGICAL protocol and statistical analysis plan prior to trial conclusion will reduce the potential for outcome-reporting or analysis bias. Trial registration: Australian and New Zealand Clinical Trials Registry (ACTRN12621000518864).

Study protocol for TARGET protein: The effect of augmented administration of enteral protein to critically ill adults on clinical outcomes: A cluster randomised, cross-sectional, double cross-over, clinical trial.

Background: It is unknown whether increasing dietary protein to 1.2-2.0 g/kg/day as recommended in international guidelines compared to current practice improves outcomes in intensive care unit (ICU) patients. The TARGET Protein trial will evaluate this. Objective: To describe the study protocol for the TARGET Protein trial. Design setting and participants: TARGET Protein is a cluster randomised, cross-sectional, double cross-over, pragmatic clinical trial undertaken in eight ICUs in Australia and New Zealand. Each ICU will be randomised to use one of two trial enteral formulae for three months before crossing over to the other formula, which is then repeated, with enrolment continuing at each ICU for 12 months. All patients aged ≥16 years in their index ICU admission commencing enteral nutrition will be eligible for inclusion. Eligible patients will receive the trial enteral formula to which their ICU is allocated. The two trial enteral formulae are isocaloric with a difference in protein dose: intervention 100g/1000 ml and comparator 63g/1000 ml. Staggered recruitment commenced in May 2022. Main outcomes measures: The primary outcome is days free of the index hospital and alive at day 90. Secondary outcomes include days free of the index hospital at day 90 in survivors, alive at day 90, duration of invasive ventilation, ICU and hospital length of stay, incidence of tracheostomy insertion, renal replacement therapy, and discharge destination. Conclusion: TARGET Protein aims to determine whether augmented enteral protein delivery reduces days free of the index hospital and alive at day 90. Trial registration: Australian New Zealand Clinical Trials Registry (ACTRN12621001484831).

Aggression, violence and threatening behaviour during critical illness.

Objective: This article aims to quantify prevalence of patient aggression or threatened/actual violence during critical illness. Design: This is a retrospective cohort study. Setting: This study was conducted in single adult trauma intensive care unit (ICU). Participants: Patients aged 18 years or over, admitted between January 2015 and December 2020, who triggered a "Code Grey" response due to aggression or threatened/actual violence. Main outcome measure: The primary outcome was prevalence of Code Grey events. Secondary outcomes included unadjusted and adjusted (logistic mixed model) effects of patient demographics, diagnoses and severity of illness on Code Grey events. Results: There were 16175 ICU admissions relating to 14085 patients and 807 Code Grey events involving 379 (2.7%) patients. The observed count of events increased progressively from 2015 (n = 77) to 2020 (n = 204). For patients with a Code Grey, the median count of events was 3 (range 1-33). Independent predictors of at least one ICU Code Grey event included male sex (OR 2.5; 95% CI 1.8 to 3.4), young age (most elevated odds ratio in patients 20-30 years), admission from the emergency department (OR 2.8, 95% CI 2.1 to 3.6) and a trauma diagnosis (OR 1.4, 95% CI 1.1 to 1.9). Code Grey patients had longer admissions with a reduced risk of death. Conclusions: The prevalence of Code Grey events in ICU appears to be increasing. Patients may have repeated events. Younger male patients admitted to ICU via the emergency department with a trauma or medical diagnosis are at greatest risk of a Code Grey event.

Cell-free DNA as a potential biomarker for acute myocardial infarction: A systematic review and meta-analysis.

Background: Tissue necrosis releases cell-free deoxyribonucleic acid (cfDNA), leading to rapid increases in plasma concentration with clearance independent of kidney function. Aim: To explore the diagnostic role of cfDNA in acute myocardial infarction (AMI). Methods: This systematic review and meta-analysis included studies of cfDNA in patients with AMI and a comparator group without AMI. The quality assessment of diagnostic accuracy studies-2 (QUADAS-2) tool was used, with AMI determined from the criteria of the original study. Standardised mean differences (SMD) were obtained using a random-effects inverse variance model. Heterogeneity was reported as I2. Pooled sensitivity and specificity were computed using a bivariate model. The area under the curve (AUC) was estimated from a hierarchical summary receiver operating characteristics curve. Results: Seventeen studies were identified involving 1804 patients (n = 819 in the AMI group, n = 985 in the comparator group). Circulating cfDNA concentrations were greater in the AMI group (SMD 3.47 (95%CI: 2.54-4.41, p < 0.001)). The studies were of variable methodological quality with substantial heterogeneity (I2 = 98%, p < 0.001), possibly due to the differences in cfDNA quantification methodologies (Chi2 25.16, p < 0.001, I2 = 92%). Diagnostic accuracy was determined using six studies (n = 804), which yielded a sensitivity of 87% (95%CI: 72%-95%) and specificity of 96% (95%CI: 92%-98%). The AUC was 0.96 (95%CI: 0.93-0.98). Two studies reported a relationship between peak cfDNA and peak troponin. No studies reported data for patients with pre-existing kidney impairment. Conclusion: Plasma cfDNA appears to be a reliable biomarker of myocardial injury. Inferences from existing results are limited owing to methodology heterogeneity.