The Montreal Protocol protects the terrestrial carbon sink.

The control of the production of ozone-depleting substances through the Montreal Protocol means that the stratospheric ozone layer is recovering1 and that consequent increases in harmful surface ultraviolet radiation are being avoided2,3. The Montreal Protocol has co-benefits for climate change mitigation, because ozone-depleting substances are potent greenhouse gases4-7. The avoided ultraviolet radiation and climate change also have co-benefits for plants and their capacity to store carbon through photosynthesis8, but this has not previously been investigated. Here, using a modelling framework that couples ozone depletion, climate change, damage to plants by ultraviolet radiation and the carbon cycle, we explore the benefits of avoided increases in ultraviolet radiation and changes in climate on the terrestrial biosphere and its capacity as a carbon sink. Considering a range of strengths for the effect of ultraviolet radiation on plant growth8-12, we estimate that there could have been 325-690 billion tonnes less carbon held in plants and soils by the end of this century (2080-2099) without the Montreal Protocol (as compared to climate projections with controls on ozone-depleting substances). This change could have resulted in an additional 115-235 parts per million of atmospheric carbon dioxide, which might have led to additional warming of global-mean surface temperature by 0.50-1.0 degrees. Our findings suggest that the Montreal Protocol may also be helping to mitigate climate change through avoided decreases in the land carbon sink.

Prehospital Tranexamic Acid for Severe Trauma.

BACKGROUND: Whether prehospital administration of tranexamic acid increases the likelihood of survival with a favorable functional outcome among patients with major trauma and suspected trauma-induced coagulopathy who are being treated in advanced trauma systems is uncertain. METHODS: We randomly assigned adults with major trauma who were at risk for trauma-induced coagulopathy to receive tranexamic acid (administered intravenously as a bolus dose of 1 g before hospital admission, followed by a 1-g infusion over a period of 8 hours after arrival at the hospital) or matched placebo. The primary outcome was survival with a favorable functional outcome at 6 months after injury, as assessed with the use of the Glasgow Outcome Scale-Extended (GOS-E). Levels on the GOS-E range from 1 (death) to 8 ("upper good recovery" [no injury-related problems]). We defined survival with a favorable functional outcome as a GOS-E level of 5 ("lower moderate disability") or higher. Secondary outcomes included death from any cause within 28 days and within 6 months after injury. RESULTS: A total of 1310 patients were recruited by 15 emergency medical services in Australia, New Zealand, and Germany. Of these patients, 661 were assigned to receive tranexamic acid, and 646 were assigned to receive placebo; the trial-group assignment was unknown for 3 patients. Survival with a favorable functional outcome at 6 months occurred in 307 of 572 patients (53.7%) in the tranexamic acid group and in 299 of 559 (53.5%) in the placebo group (risk ratio, 1.00; 95% confidence interval [CI], 0.90 to 1.12; P = 0.95). At 28 days after injury, 113 of 653 patients (17.3%) in the tranexamic acid group and 139 of 637 (21.8%) in the placebo group had died (risk ratio, 0.79; 95% CI, 0.63 to 0.99). By 6 months, 123 of 648 patients (19.0%) in the tranexamic acid group and 144 of 629 (22.9%) in the placebo group had died (risk ratio, 0.83; 95% CI, 0.67 to 1.03). The number of serious adverse events, including vascular occlusive events, did not differ meaningfully between the groups. CONCLUSIONS: Among adults with major trauma and suspected trauma-induced coagulopathy who were being treated in advanced trauma systems, prehospital administration of tranexamic acid followed by an infusion over 8 hours did not result in a greater number of patients surviving with a favorable functional outcome at 6 months than placebo. (Funded by the Australian National Health and Medical Research Council and others; PATCH-Trauma ClinicalTrials.gov number, NCT02187120.).

Early Active Mobilization during Mechanical Ventilation in the ICU.

BACKGROUND: Intensive care unit (ICU)-acquired weakness often develops in patients who are undergoing invasive mechanical ventilation. Early active mobilization may mitigate ICU-acquired weakness, increase survival, and reduce disability. METHODS: We randomly assigned 750 adult patients in the ICU who were undergoing invasive mechanical ventilation to receive increased early mobilization (sedation minimization and daily physiotherapy) or usual care (the level of mobilization that was normally provided in each ICU). The primary outcome was the number of days that the patients were alive and out of the hospital at 180 days after randomization. RESULTS: The median number of days that patients were alive and out of the hospital was 143 (interquartile range, 21 to 161) in the early-mobilization group and 145 days (interquartile range, 51 to 164) in the usual-care group (absolute difference, -2.0 days; 95% confidence interval [CI], -10 to 6; P = 0.62). The mean (±SD) daily duration of active mobilization was 20.8±14.6 minutes and 8.8±9.0 minutes in the two groups, respectively (difference, 12.0 minutes per day; 95% CI, 10.4 to 13.6). A total of 77% of the patients in both groups were able to stand by a median interval of 3 days and 5 days, respectively (difference, -2 days; 95% CI, -3.4 to -0.6). By day 180, death had occurred in 22.5% of the patients in the early-mobilization group and in 19.5% of those in the usual-care group (odds ratio, 1.15; 95% CI, 0.81 to 1.65). Among survivors, quality of life, activities of daily living, disability, cognitive function, and psychological function were similar in the two groups. Serious adverse events were reported in 7 patients in the early-mobilization group and in 1 patient in the usual-care group. Adverse events that were potentially due to mobilization (arrhythmias, altered blood pressure, and desaturation) were reported in 34 of 371 patients (9.2%) in the early-mobilization group and in 15 of 370 patients (4.1%) in the usual-care group (P = 0.005). CONCLUSIONS: Among adults undergoing mechanical ventilation in the ICU, an increase in early active mobilization did not result in a significantly greater number of days that patients were alive and out of the hospital than did the usual level of mobilization in the ICU. The intervention was associated with increased adverse events. (Funded by the National Health and Medical Research Council of Australia and the Health Research Council of New Zealand; TEAM ClinicalTrials.gov number, NCT03133377.).

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.).

Impact of High Dose Early Mobilization on Outcomes for Patients with Diabetes: A Secondary Analysis of the TEAM Trial.

RATIONALE: Patients with diabetes represent almost 20% of all ICU admissions and might respond differently to high dose early active mobilization. OBJECTIVES: To assess whether diabetes modified the relationship between the dose of early mobilization on clinical outcomes in the TEAM trial. METHODS: All TEAM trial patients were included. The primary outcome was days alive and out of hospital at day 180. Secondary outcomes included 180-day mortality and long-term functional outcomes at day 180. Logistic and median regression models were used to explore the effect of high dose early mobilization on outcomes by diabetes status. MEASUREMENTS AND MAIN RESULTS: All 741 patients from the original trial were included. Of these, 159 patients (21.4%) had diabetes. Patients with diabetes had a lower number of days alive and out of hospital at day 180 (124 [0-153] vs. 147 [82-164], p = 0.013), and higher 180-day mortality (30% vs. 18%, p = 0.044). In patients receiving high dose early mobilization, days alive and out of hospital at day 180 was 73.0 (0.0 - 144.5) in patients with diabetes and 146.5 (95.8 - 163.0) in patients without diabetes (p for interaction = 0.108). However, in patients with diabetes, high dose early mobilization increased the odds of mortality at 180 days (adjusted odds ratio 3.47; 95% confidence interval [CI], 1.67-7.61, p value for interaction, 0.001). CONCLUSIONS: In this secondary analysis of the TEAM trial, in patients with diabetes, a high dose early mobilization strategy did not significantly decrease the number of days alive and out of hospital at day 180 but it increased 180-day mortality.

Hypothermia versus Normothermia after Out-of-Hospital Cardiac Arrest.

BACKGROUND: Targeted temperature management is recommended for patients after cardiac arrest, but the supporting evidence is of low certainty. METHODS: In an open-label trial with blinded assessment of outcomes, we randomly assigned 1900 adults with coma who had had an out-of-hospital cardiac arrest of presumed cardiac or unknown cause to undergo targeted hypothermia at 33°C, followed by controlled rewarming, or targeted normothermia with early treatment of fever (body temperature, ≥37.8°C). The primary outcome was death from any cause at 6 months. Secondary outcomes included functional outcome at 6 months as assessed with the modified Rankin scale. Prespecified subgroups were defined according to sex, age, initial cardiac rhythm, time to return of spontaneous circulation, and presence or absence of shock on admission. Prespecified adverse events were pneumonia, sepsis, bleeding, arrhythmia resulting in hemodynamic compromise, and skin complications related to the temperature management device. RESULTS: A total of 1850 patients were evaluated for the primary outcome. At 6 months, 465 of 925 patients (50%) in the hypothermia group had died, as compared with 446 of 925 (48%) in the normothermia group (relative risk with hypothermia, 1.04; 95% confidence interval [CI], 0.94 to 1.14; P = 0.37). Of the 1747 patients in whom the functional outcome was assessed, 488 of 881 (55%) in the hypothermia group had moderately severe disability or worse (modified Rankin scale score ≥4), as compared with 479 of 866 (55%) in the normothermia group (relative risk with hypothermia, 1.00; 95% CI, 0.92 to 1.09). Outcomes were consistent in the prespecified subgroups. Arrhythmia resulting in hemodynamic compromise was more common in the hypothermia group than in the normothermia group (24% vs. 17%, P<0.001). The incidence of other adverse events did not differ significantly between the two groups. CONCLUSIONS: In patients with coma after out-of-hospital cardiac arrest, targeted hypothermia did not lead to a lower incidence of death by 6 months than targeted normothermia. (Funded by the Swedish Research Council and others; TTM2 ClinicalTrials.gov number, NCT02908308.).

The future of hyperdiverse tropical ecosystems.

The tropics contain the overwhelming majority of Earth's biodiversity: their terrestrial, freshwater and marine ecosystems hold more than three-quarters of all species, including almost all shallow-water corals and over 90% of terrestrial birds. However, tropical ecosystems are also subject to pervasive and interacting stressors, such as deforestation, overfishing and climate change, and they are set within a socio-economic context that includes growing pressure from an increasingly globalized world, larger and more affluent tropical populations, and weak governance and response capacities. Concerted local, national and international actions are urgently required to prevent a collapse of tropical biodiversity.

Evolving Management Practices for Early Sepsis-induced Hypoperfusion: A Narrative Review.

Sepsis causes significant morbidity and mortality worldwide. Resuscitation is a cornerstone of management. This review covers five areas of evolving practice in the management of early sepsis-induced hypoperfusion: fluid resuscitation volume, timing of vasopressor initiation, resuscitation targets, route of vasopressor administration, and use of invasive blood pressure monitoring. For each topic, we review the seminal evidence, discuss the evolution of practice over time, and highlight questions for additional research. Intravenous fluids are a core component of early sepsis resuscitation. However, with growing concerns about the harms of fluid, practice is evolving toward smaller-volume resuscitation, which is often paired with earlier vasopressor initiation. Large trials of fluid-restrictive, vasopressor-early strategies are providing more information about the safety and potential benefit of these approaches. Lowering blood pressure targets is a means to prevent fluid overload and reduce exposure to vasopressors; mean arterial pressure targets of 60-65 mm Hg appear to be safe, at least in older patients. With the trend toward earlier vasopressor initiation, the need for central administration of vasopressors has been questioned, and peripheral vasopressor use is increasing, although it is not universally accepted. Similarly, although guidelines suggest the use of invasive blood pressure monitoring with arterial catheters in patients receiving vasopressors, blood pressure cuffs are less invasive and often sufficient. Overall, the management of early sepsis-induced hypoperfusion is evolving toward fluid-sparing and less-invasive strategies. However, many questions remain, and additional data are needed to further optimize our approach to resuscitation.

Public perception of participation in low-risk clinical trials in critical care using waived consent: a Canadian national survey.

PURPOSE: The acceptability of waiver of consent for participation in clinical research in intensive care unit (ICU) settings is uncertain. We sought to survey the Canadian public to assess levels of support, comfort, and acceptability for waived consent for low-risk clinical trials. METHODS: We performed a prospective cross-sectional survey of the Canadian public aged 18 yr or older. The survey was conducted by Ipsos between 19 and 23 November 2020. The survey content was derived from a literature review and in consultation with a patient and family partnership committee. The survey focused on attitudes and beliefs on waived consent for participation in low-risk clinical trials in ICU settings. The survey contained 35 items focused on sociodemographics, general health status, participation in medical research, and levels of support and comfort with research and with waived consent. The survey used a case study of a low-risk clinical trial intervention in ICU patients. Analysis was descriptive. RESULTS: We included 2,000 participants, 38% of whom reported experience with ICU and 16% with medical research. Participation in medical research was more common among those with postsecondary education, those with chronic disease, and those who were employed in health care. Most (80%) would support a model of waived consent for low-risk clinical trials, citing medical benefits (36%) and low perceived risk (34%). Most (77%) were comfortable with personally participating in a low-risk clinical trial. Most (80%) believed waived consent approaches were acceptable. Half (52%) believed the waived consent process should provide information about the research and include the option of opting out. When asked whether participants should always give full informed consent, regardless of the practicality or level of risk, 74% and 72% agreed, respectively. CONCLUSIONS: There is public support for models of waived consent for participation in low-risk pragmatic clinical trials in ICU settings in Canada; however, this is not universal. This information can inform and guide education, ethics, policy, and legal discussion on consent models.

RéSUMé: OBJECTIF: L'acceptabilité de la renonciation au consentement pour la participation à la recherche clinique à l'unité de soins intensifs (USI) est incertaine. Nous avons cherché à sonder la population canadienne afin d'évaluer les niveaux de soutien, de confort et d'acceptabilité de la renonciation au consentement pour les études cliniques à faible risque. MéTHODE: Nous avons réalisé un sondage transversal prospectif auprès de la population canadienne âgée de 18 ans et plus. Le sondage a été réalisé par Ipsos entre le 19 et le 23 novembre 2020. Le contenu du sondage a été élaboré à partir d'une revue de la littérature et en consultation avec un comité de partenariat composé de patient·es et de familles. Le sondage portait sur les attitudes et les croyances à l'égard de la renonciation au consentement pour participer à des études cliniques à faible risque dans les unités de soins intensifs. Le sondage comportait 35 questions axées sur les données sociodémographiques, l'état de santé général, la participation à la recherche médicale et les niveaux de soutien et de confort à l'égard de la recherche et de la renonciation au consentement. Le sondage s'est appuyé sur une étude de cas d'une intervention d'étude clinique à faible risque chez des patient·es des soins intensifs. L'analyse était descriptive. RéSULTATS: Nous avons inclus 2000 personnes, dont 38 % ont déclaré avoir eu des expériences en soins intensifs et 16 % en recherche médicale. La participation à la recherche médicale était plus fréquente chez les personnes ayant fait des études postsecondaires, celles atteintes de maladies chroniques et celles qui travaillaient dans le domaine des soins de santé. La plupart d'entre elles (80 %) appuieraient un modèle de renonciation au consentement pour les études cliniques à faible risque, citant les avantages médicaux (36 %) et le faible risque perçu (34 %). La majorité des personnes répondantes (77 %) étaient à l'aise à l'idée de participer personnellement à une étude clinique à faible risque. La plupart d'entre elles (80 %) croyaient que les approches fondées sur la renonciation au consentement étaient acceptables. La moitié (52 %) estimaient que le processus de renonciation au consentement devrait fournir des renseignements sur la recherche et inclure la possibilité de se retirer. Lorsqu'on leur a demandé si les participant·es devraient toujours donner un consentement éclairé complet, quel que soit l'aspect pratique ou le niveau de risque, 74 % et 72 % ont répondu par l'affirmative, respectivement. CONCLUSION: Il y a un appui public pour les modèles de renonciation au consentement quant à la participation à des études cliniques pragmatiques à faible risque dans les unités de soins intensifs au Canada; cet appui n'est toutefois pas universel. Ces renseignements peuvent éclairer et orienter l'éducation, l'éthique, les politiques et les discussions juridiques sur les modèles de consentement.

Individualized Treatment Effects of Oxygen Targets in Mechanically Ventilated Critically Ill Adults.

Importance: Among critically ill adults, randomized trials have not found oxygenation targets to affect outcomes overall. Whether the effects of oxygenation targets differ based on an individual's characteristics is unknown. Objective: To determine whether an individual's characteristics modify the effect of lower vs higher peripheral oxygenation-saturation (Spo2) targets on mortality. Design, Setting, and Participants: A machine learning model to predict the effect of treatment with a lower vs higher Spo2 target on mortality for individual patients was derived in the Pragmatic Investigation of Optimal Oxygen Targets (PILOT) trial and externally validated in the Intensive Care Unit Randomized Trial Comparing Two Approaches to Oxygen Therapy (ICU-ROX) trial. Critically ill adults received invasive mechanical ventilation in an intensive care unit (ICU) in the United States between July 2018 and August 2021 for PILOT (n = 1682) and in 21 ICUs in Australia and New Zealand between September 2015 and May 2018 for ICU-ROX (n = 965). Exposures: Randomization to a lower vs higher Spo2 target group. Main Outcome and Measure: 28-Day mortality. Results: In the ICU-ROX validation cohort, the predicted effect of treatment with a lower vs higher Spo2 target for individual patients ranged from a 27.2% absolute reduction to a 34.4% absolute increase in 28-day mortality. For example, patients predicted to benefit from a lower Spo2 target had a higher prevalence of acute brain injury, whereas patients predicted to benefit from a higher Spo2 target had a higher prevalence of sepsis and abnormally elevated vital signs. Patients predicted to benefit from a lower Spo2 target experienced lower mortality when randomized to the lower Spo2 group, whereas patients predicted to benefit from a higher Spo2 target experienced lower mortality when randomized to the higher Spo2 group (likelihood ratio test for effect modification P = .02). The use of a Spo2 target predicted to be best for each patient, instead of the randomized Spo2 target, would have reduced the absolute overall mortality by 6.4% (95% CI, 1.9%-10.9%). Conclusion and relevance: Oxygenation targets that are individualized using machine learning analyses of randomized trials may reduce mortality for critically ill adults. A prospective trial evaluating the use of individualized oxygenation targets is needed.

Sodium Bicarbonate for Metabolic Acidosis in the ICU: Results of a Pilot Randomized Double-Blind Clinical Trial.

OBJECTIVES: To identify the best population, design of the intervention, and to assess between-group biochemical separation, in preparation for a future phase III trial. DESIGN: Investigator-initiated, parallel-group, pilot randomized double-blind trial. SETTING: Eight ICUs in Australia, New Zealand, and Japan, with participants recruited from April 2021 to August 2022. PATIENTS: Thirty patients greater than or equal to 18 years, within 48 hours of admission to the ICU, receiving a vasopressor, and with metabolic acidosis (pH < 7.30, base excess [BE] < -4 mEq/L, and Pa co2 < 45 mm Hg). INTERVENTIONS: Sodium bicarbonate or placebo (5% dextrose). MEASUREMENTS AND MAIN RESULT: The primary feasibility aim was to assess eligibility, recruitment rate, protocol compliance, and acid-base group separation. The primary clinical outcome was the number of hours alive and free of vasopressors on day 7. The recruitment rate and the enrollment-to-screening ratio were 1.9 patients per month and 0.13 patients, respectively. Time until BE correction (median difference, -45.86 [95% CI, -63.11 to -28.61] hr; p < 0.001) and pH correction (median difference, -10.69 [95% CI, -19.16 to -2.22] hr; p = 0.020) were shorter in the sodium bicarbonate group, and mean bicarbonate levels in the first 24 hours were higher (median difference, 6.50 [95% CI, 4.18 to 8.82] mmol/L; p < 0.001). Seven days after randomization, patients in the sodium bicarbonate and placebo group had a median of 132.2 (85.6-139.1) and 97.1 (69.3-132.4) hours alive and free of vasopressor, respectively (median difference, 35.07 [95% CI, -9.14 to 79.28]; p = 0.131). Recurrence of metabolic acidosis in the first 7 days of follow-up was lower in the sodium bicarbonate group (3 [20.0%] vs. 15 [100.0%]; p < 0.001). No adverse events were reported. CONCLUSIONS: The findings confirm the feasibility of a larger phase III sodium bicarbonate trial; eligibility criteria may require modification to facilitate recruitment.

Atrial Fibrillation (AFIB) in the ICU: Incidence, Risk Factors, and Outcomes: The International AFIB-ICU Cohort Study.

OBJECTIVES: To assess the incidence, risk factors, and outcomes of atrial fibrillation (AF) in the ICU and to describe current practice in the management of AF. DESIGN: Multicenter, prospective, inception cohort study. SETTING: Forty-four ICUs in 12 countries in four geographical regions. SUBJECTS: Adult, acutely admitted ICU patients without a history of persistent/permanent AF or recent cardiac surgery were enrolled; inception periods were from October 2020 to June 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We included 1,423 ICU patients and analyzed 1,415 (99.4%), among whom 221 patients had 539 episodes of AF. Most (59%) episodes were diagnosed with continuous electrocardiogram monitoring. The incidence of AF was 15.6% (95% CI, 13.8-17.6), of which newly developed AF was 13.3% (11.5-15.1). A history of arterial hypertension, paroxysmal AF, sepsis, or high disease severity at ICU admission was associated with AF. Used interventions to manage AF were fluid bolus 19% (95% CI 16-23), magnesium 16% (13-20), potassium 15% (12-19), amiodarone 51% (47-55), beta-1 selective blockers 34% (30-38), calcium channel blockers 4% (2-6), digoxin 16% (12-19), and direct current cardioversion in 4% (2-6). Patients with AF had more ischemic, thromboembolic (13.6% vs 7.9%), and severe bleeding events (5.9% vs 2.1%), and higher mortality (41.2% vs 25.2%) than those without AF. The adjusted cause-specific hazard ratio for 90-day mortality by AF was 1.38 (95% CI, 0.95-1.99). CONCLUSIONS: In ICU patients, AF occurred in one of six and was associated with different conditions. AF was associated with worse outcomes while not statistically significantly associated with 90-day mortality in the adjusted analyses. We observed variations in the diagnostic and management strategies for AF.

The Effect of a Liberal Approach to Glucose Control in Critically Ill Patients with Type 2 Diabetes: A Multicenter, Parallel-Group, Open-Label Randomized Clinical Trial.

Rationale: Blood glucose concentrations affect outcomes in critically ill patients, but the optimal target blood glucose range in those with type 2 diabetes is unknown. Objectives: To evaluate the effects of a "liberal" approach to targeted blood glucose range during ICU admission. Methods: This mutlicenter, parallel-group, open-label randomized clinical trial included 419 adult patients with type 2 diabetes expected to be in the ICU on at least three consecutive days. In the intervention group intravenous insulin was commenced at a blood glucose >252 mg/dl and titrated to a target range of 180-252 mg/dl. In the comparator group insulin was commenced at a blood glucose >180 mg/dl and titrated to a target range of 108-180 mg/dl. The primary outcome was incident hypoglycemia (<72 mg/dl). Secondary outcomes included glucose metrics and clinical outcomes. Measurements and Main Results: By Day 28, at least one episode of hypoglycemia occurred in 10 of 210 (5%) patients assigned the intervention and 38 of 209 (18%) patients assigned the comparator (incident rate ratio, 0.21 [95% confidence interval (CI), 0.09 to 0.49]; P < 0.001). Those assigned the intervention had greater blood glucose concentrations (daily mean, minimum, maximum), less glucose variability, and less relative hypoglycemia (P < 0.001 for all comparisons). By Day 90, 62 of 210 (29.5%) in the intervention and 52 of 209 (24.9%) in the comparator group had died (absolute difference, 4.6 percentage points [95% CI, -3.9% to 13.2%]; P = 0.29). Conclusions: A liberal approach to blood glucose targets reduced incident hypoglycemia but did not improve patient-centered outcomes. Clinical trial registered with Australian New Zealand Clinical Trials Registry (ACTRN 12616001135404).

Oxygen targets and 6-month outcome after out of hospital cardiac arrest: a pre-planned sub-analysis of the targeted hypothermia versus targeted normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial.

BACKGROUND: Optimal oxygen targets in patients resuscitated after cardiac arrest are uncertain. The primary aim of this study was to describe the values of partial pressure of oxygen values (PaO2) and the episodes of hypoxemia and hyperoxemia occurring within the first 72 h of mechanical ventilation in out of hospital cardiac arrest (OHCA) patients. The secondary aim was to evaluate the association of PaO2 with patients' outcome. METHODS: Preplanned secondary analysis of the targeted hypothermia versus targeted normothermia after OHCA (TTM2) trial. Arterial blood gases values were collected from randomization every 4 h for the first 32 h, and then, every 8 h until day 3. Hypoxemia was defined as PaO2 < 60 mmHg and severe hyperoxemia as PaO2 > 300 mmHg. Mortality and poor neurological outcome (defined according to modified Rankin scale) were collected at 6 months. RESULTS: 1418 patients were included in the analysis. The mean age was 64 ± 14 years, and 292 patients (20.6%) were female. 24.9% of patients had at least one episode of hypoxemia, and 7.6% of patients had at least one episode of severe hyperoxemia. Both hypoxemia and hyperoxemia were independently associated with 6-month mortality, but not with poor neurological outcome. The best cutoff point associated with 6-month mortality for hypoxemia was 69 mmHg (Risk Ratio, RR = 1.009, 95% CI 0.93-1.09), and for hyperoxemia was 195 mmHg (RR = 1.006, 95% CI 0.95-1.06). The time exposure, i.e., the area under the curve (PaO2-AUC), for hyperoxemia was significantly associated with mortality (p = 0.003). CONCLUSIONS: In OHCA patients, both hypoxemia and hyperoxemia are associated with 6-months mortality, with an effect mediated by the timing exposure to high values of oxygen. Precise titration of oxygen levels should be considered in this group of patients. TRIAL REGISTRATION: clinicaltrials.gov NCT02908308 , Registered September 20, 2016.

Speed of cooling after cardiac arrest in relation to the intervention effect: a sub-study from the TTM2-trial.

BACKGROUND: Targeted temperature management (TTM) is recommended following cardiac arrest; however, time to target temperature varies in clinical practice. We hypothesised the effects of a target temperature of 33 °C when compared to normothermia would differ based on average time to hypothermia and those patients achieving hypothermia fastest would have more favorable outcomes. METHODS: In this post-hoc analysis of the TTM-2 trial, patients after out of hospital cardiac arrest were randomized to targeted hypothermia (33 °C), followed by controlled re-warming, or normothermia with early treatment of fever (body temperature, ≥ 37.8 °C). The average temperature at 4 h (240 min) after return of spontaneous circulation (ROSC) was calculated for participating sites. Primary outcome was death from any cause at 6 months. Secondary outcome was poor functional outcome at 6 months (score of 4-6 on modified Rankin scale). RESULTS: A total of 1592 participants were evaluated for the primary outcome. We found no evidence of heterogeneity of intervention effect based on the average time to target temperature on mortality (p = 0.17). Of patients allocated to hypothermia at the fastest sites, 71 of 145 (49%) had died compared to 68 of 148 (46%) of the normothermia group (relative risk with hypothermia, 1.07; 95% confidence interval 0.84-1.36). Poor functional outcome was reported in 74/144 (51%) patients in the hypothermia group, and 75/147 (51%) patients in the normothermia group (relative risk with hypothermia 1.01 (95% CI 0.80-1.26). CONCLUSIONS: Using a hospital's average time to hypothermia did not significantly alter the effect of TTM of 33 °C compared to normothermia and early treatment of fever.

Management of acute atrial fibrillation in the intensive care unit: An international survey.

BACKGROUND: Atrial fibrillation (AF) is common in intensive care unit (ICU) patients and is associated with poor outcomes. Different management strategies exist, but the evidence is limited and derived from non-ICU patients. This international survey of ICU doctors evaluated the preferred management of acute AF in ICU patients. METHOD: We conducted an international online survey of ICU doctors with 27 questions about the preferred management of acute AF in the ICU, including antiarrhythmic therapy in hemodynamically stable and unstable patients and use of anticoagulant therapy. RESULTS: A total of 910 respondents from 70 ICUs in 14 countries participated in the survey with 24%-100% of doctors from sites responding. Most ICUs (80%) did not have a local guideline for the management of acute AF. The preferred first-line strategy for the management of hemodynamically stable patients with acute AF was observation (95% of respondents), rhythm control (3%), or rate control (2%). For hemodynamically unstable patients, the preferred strategy was observation (48%), rhythm control (48%), or rate control (4%). Overall, preferred antiarrhythmic interventions included amiodarone, direct current cardioversion, beta-blockers other than sotalol, and magnesium in that order. A total of 67% preferred using anticoagulant therapy in ICU patients with AF, among whom 61% preferred therapeutic dose anticoagulants and 39% prophylactic dose anticoagulants. CONCLUSION: This international survey indicated considerable practice variation among ICU doctors in the clinical management of acute AF, including the overall management strategies and the use of antiarrhythmic interventions and anticoagulants.

Effect of Nitric Oxide via Cardiopulmonary Bypass on Ventilator-Free Days in Young Children Undergoing Congenital Heart Disease Surgery: The NITRIC Randomized Clinical Trial.

Importance: In children undergoing heart surgery, nitric oxide administered into the gas flow of the cardiopulmonary bypass oxygenator may reduce postoperative low cardiac output syndrome, leading to improved recovery and shorter duration of respiratory support. It remains uncertain whether nitric oxide administered into the cardiopulmonary bypass oxygenator improves ventilator-free days (days alive and free from mechanical ventilation). Objective: To determine the effect of nitric oxide applied into the cardiopulmonary bypass oxygenator vs standard care on ventilator-free days in children undergoing surgery for congenital heart disease. Design, Setting, and Participants: Double-blind, multicenter, randomized clinical trial in 6 pediatric cardiac surgical centers in Australia, New Zealand, and the Netherlands. A total of 1371 children younger than 2 years undergoing congenital heart surgery were randomized between July 2017 and April 2021, with 28-day follow-up of the last participant completed on May 24, 2021. Interventions: Patients were assigned to receive nitric oxide at 20 ppm delivered into the cardiopulmonary bypass oxygenator (n = 679) or standard care cardiopulmonary bypass without nitric oxide (n = 685). Main Outcomes and Measures: The primary end point was the number of ventilator-free days from commencement of bypass until day 28. There were 4 secondary end points including a composite of low cardiac output syndrome, extracorporeal life support, or death; length of stay in the intensive care unit; length of stay in the hospital; and postoperative troponin levels. Results: Among 1371 patients who were randomized (mean [SD] age, 21.2 [23.5] weeks; 587 girls [42.8%]), 1364 (99.5%) completed the trial. The number of ventilator-free days did not differ significantly between the nitric oxide and standard care groups, with a median of 26.6 days (IQR, 24.4 to 27.4) vs 26.4 days (IQR, 24.0 to 27.2), respectively, for an absolute difference of -0.01 days (95% CI, -0.25 to 0.22; P = .92). A total of 22.5% of the nitric oxide group and 20.9% of the standard care group developed low cardiac output syndrome within 48 hours, needed extracorporeal support within 48 hours, or died by day 28, for an adjusted odds ratio of 1.12 (95% CI, 0.85 to 1.47). Other secondary outcomes were not significantly different between the groups. Conclusions and Relevance: In children younger than 2 years undergoing cardiopulmonary bypass surgery for congenital heart disease, the use of nitric oxide via cardiopulmonary bypass did not significantly affect the number of ventilator-free days. These findings do not support the use of nitric oxide delivered into the cardiopulmonary bypass oxygenator during heart surgery. Trial Registration: anzctr.org.au Identifier: ACTRN12617000821392.

Effect of Selective Decontamination of the Digestive Tract on Hospital Mortality in Critically Ill Patients Receiving Mechanical Ventilation: A Randomized Clinical Trial.

Importance: Whether selective decontamination of the digestive tract (SDD) reduces mortality in critically ill patients remains uncertain. Objective: To determine whether SDD reduces in-hospital mortality in critically ill adults. Design, Setting, and Participants: A cluster, crossover, randomized clinical trial that recruited 5982 mechanically ventilated adults from 19 intensive care units (ICUs) in Australia between April 2018 and May 2021 (final follow-up, August 2021). A contemporaneous ecological assessment recruited 8599 patients from participating ICUs between May 2017 and August 2021. Interventions: ICUs were randomly assigned to adopt or not adopt a SDD strategy for 2 alternating 12-month periods, separated by a 3-month interperiod gap. Patients in the SDD group (n = 2791) received a 6-hourly application of an oral paste and administration of a gastric suspension containing colistin, tobramycin, and nystatin for the duration of mechanical ventilation, plus a 4-day course of an intravenous antibiotic with a suitable antimicrobial spectrum. Patients in the control group (n = 3191) received standard care. Main Outcomes and Measures: The primary outcome was in-hospital mortality within 90 days. There were 8 secondary outcomes, including the proportion of patients with new positive blood cultures, antibiotic-resistant organisms (AROs), and Clostridioides difficile infections. For the ecological assessment, a noninferiority margin of 2% was prespecified for 3 outcomes including new cultures of AROs. Results: Of 5982 patients (mean age, 58.3 years; 36.8% women) enrolled from 19 ICUs, all patients completed the trial. There were 753/2791 (27.0%) and 928/3191 (29.1%) in-hospital deaths in the SDD and standard care groups, respectively (mean difference, -1.7% [95% CI, -4.8% to 1.3%]; odds ratio, 0.91 [95% CI, 0.82-1.02]; P = .12). Of 8 prespecified secondary outcomes, 6 showed no significant differences. In the SDD vs standard care groups, 23.1% vs 34.6% had new ARO cultures (absolute difference, -11.0%; 95% CI, -14.7% to -7.3%), 5.6% vs 8.1% had new positive blood cultures (absolute difference, -1.95%; 95% CI, -3.5% to -0.4%), and 0.5% vs 0.9% had new C difficile infections (absolute difference, -0.24%; 95% CI, -0.6% to 0.1%). In 8599 patients enrolled in the ecological assessment, use of SDD was not shown to be noninferior with regard to the change in the proportion of patients who developed new AROs (-3.3% vs -1.59%; mean difference, -1.71% [1-sided 97.5% CI, -∞ to 4.31%] and 0.88% vs 0.55%; mean difference, -0.32% [1-sided 97.5% CI, -∞ to 5.47%]) in the first and second periods, respectively. Conclusions and Relevance: Among critically ill patients receiving mechanical ventilation, SDD, compared with standard care without SDD, did not significantly reduce in-hospital mortality. However, the confidence interval around the effect estimate includes a clinically important benefit. Trial Registration: ClinicalTrials.gov Identifier: NCT02389036.

Long-term costs and cost-effectiveness of adjunctive corticosteroids for patients with septic shock in New Zealand.

OBJECTIVE: The aim of the study was to determine whether adjunctive hydrocortisone reduced healthcare expenditure and was cost-effective compared with placebo in New Zealand patients in the Adjunctive Glucocorticoid Therapy in Patients with Septic Shock (ADRENAL) trial. DESIGN: This is a health economic analysis using data linkage to New Zealand Ministry of Health databases to determine resource use, costs, and cost-effectiveness for a 24-month period. SETTING: The study was conducted in New Zealand. PARTICIPANTS AND INTERVENTION: Patients with septic shock were randomised to receive a 7-day continuous infusion of 200 mg of hydrocortisone or placebo in the ADRENAL trial. MAIN OUTCOME MEASURES: Healthcare expenditure was associated with all hospital admissions, emergency department presentations, outpatient visits, and pharmacy expenditure. Effectiveness outcomes included mortality at 6 months and 24 months and quality of life at 6 months. Cost-effectiveness outcomes were assessed with reference to quality-adjusted life years gained at 6 months and life years gained at 24 months. RESULTS: Of 3800 patients in the ADRENAL trial, 419 (11.0%) were eligible, and 405 (96.7% of those eligible) were included. The mean total costs per patient over 24 months were $143,627 ± 100,890 and $143,772 ± 97,117 for the hydrocortisone and placebo groups, respectively (p = 0.99). Intensive care unit costs for the index admission were $50,492 and $62,288 per patient for the hydrocortisone and placebo groups, respectively (p = 0.09). The mean number of quality-adjusted life years gained at 6 months and mean number of life years gained at 24 months was not significantly different by treatment group, and the probability of hydrocortisone being cost-effective was 55% at 24 months. CONCLUSIONS: In New Zealand, adjunctive hydrocortisone did not reduce total healthcare expenditure or improve outcomes compared with placebo in patients with septic shock.