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JMIR Res Protoc ; 11(5): e36261, 2022 05 20.
Article in English | MEDLINE | ID: covidwho-1862513


BACKGROUND: The LOVIT (Lessening Organ Dysfunction with Vitamin C) trial is a blinded multicenter randomized clinical trial comparing high-dose intravenous vitamin C to placebo in patients admitted to the intensive care unit with proven or suspected infection as the main diagnosis and receiving a vasopressor. OBJECTIVE: We aim to describe a prespecified statistical analysis plan (SAP) for the LOVIT trial prior to unblinding and locking of the trial database. METHODS: The SAP was designed by the LOVIT principal investigators and statisticians, and approved by the steering committee and coinvestigators. The SAP defines the primary and secondary outcomes, and describes the planned primary, secondary, and subgroup analyses. RESULTS: The SAP includes a draft participant flow diagram, tables, and planned figures. The primary outcome is a composite of mortality and persistent organ dysfunction (receipt of mechanical ventilation, vasopressors, or new renal replacement therapy) at 28 days, where day 1 is the day of randomization. All analyses will use a frequentist statistical framework. The analysis of the primary outcome will estimate the risk ratio and 95% CI in a generalized linear mixed model with binomial distribution and log link, with site as a random effect. We will perform a secondary analysis adjusting for prespecified baseline clinical variables. Subgroup analyses will include age, sex, frailty, severity of illness, Sepsis-3 definition of septic shock, baseline ascorbic acid level, and COVID-19 status. CONCLUSIONS: We have developed an SAP for the LOVIT trial and will adhere to it in the analysis phase. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/36261.

Can J Anaesth ; 69(3): 343-352, 2022 03.
Article in English | MEDLINE | ID: covidwho-1694251


PURPOSE: The COVID-19 pandemic has caused intensive care units (ICUs) to reach capacities requiring triage. A tool to predict mortality risk in ventilated patients with COVID-19 could inform decision-making and resource allocation, and allow population-level comparisons across institutions. METHODS: This retrospective cohort study included all mechanically ventilated adults with COVID-19 admitted to three tertiary care ICUs in Toronto, Ontario, between 1 March 2020 and 15 December 2020. Generalized estimating equations were used to identify variables predictive of mortality. The primary outcome was the probability of death at three-day intervals from the time of ICU admission (day 0), with risk re-calculation every three days to day 15; the final risk calculation estimated the probability of death at day 15 and beyond. A numerical algorithm was developed from the final model coefficients. RESULTS: One hundred twenty-seven patients were eligible for inclusion. Median ICU length of stay was 26.9 (interquartile range, 15.4-52.0) days. Overall mortality was 42%. From day 0 to 15, the variables age, temperature, lactate level, ventilation tidal volume, and vasopressor use significantly predicted mortality. Our final clinical risk score had an area under the receiver-operating characteristics curve of 0.9 (95% confidence interval [CI], 0.8 to 0.9). For every ten-point increase in risk score, the relative increase in the odds of death was approximately 4, with an odds ratio of 4.1 (95% CI, 2.9 to 5.9). CONCLUSION: Our dynamic prediction tool for mortality in ventilated patients with COVID-19 has excellent diagnostic properties. Notwithstanding, external validation is required before widespread implementation.

RéSUMé: OBJECTIF: En raison de la pandémie de COVID-19, les unités de soins intensifs (USI) ont atteint des taux d'occupation nécessitant un triage. Un outil pour prédire le risque de mortalité chez les patients sous ventilation atteints de COVID-19 pourrait éclairer la prise de décision et l'attribution des ressources tout en permettant des comparaisons populationnelles entre les établissements. MéTHODE: Cette étude de cohorte rétrospective a inclus tous les adultes atteints de COVID-19 sous ventilation mécanique admis dans trois USI de centres de soins tertiaires à Toronto, en Ontario, entre le 1er mars 2020 et le 15 décembre 2020. Des équations d'estimation généralisées ont été utilisées pour identifier les variables prédictives de mortalité. Le critère d'évaluation principal était la probabilité de décès à des intervalles de trois jours à partir du moment de l'admission à l'USI (jour 0), avec un nouveau calcul du risque tous les trois jours jusqu'au jour 15; le calcul final du risque a estimé la probabilité de décès au jour 15 et au-delà. Un algorithme numérique a été mis au point à partir des coefficients du modèle final. RéSULTATS: Cent vingt-sept patients étaient éligibles à l'inclusion. La durée médiane de séjour à l'USI était de 26,9 jours (écart interquartile, 15,4 à 52,0). La mortalité globale était de 42 %. Du jour 0 au jour 15, les variables que sont l'âge, la température, les taux de lactate, le volume courant de ventilation et l'utilisation de vasopresseurs ont constitué des prédicteurs significatifs de mortalité. Notre score de risque clinique final avait une aire sous la courbe ROC de 0,9 (intervalle de confiance [IC] à 95 %, 0,8 à 0,9). Pour chaque augmentation de dix points du score de risque, l'augmentation relative des risques de décès était d'environ 4, avec un rapport de cotes de 4,1 (IC 95 %, 2,9 à 5,9). CONCLUSION: Notre outil de prédiction dynamique de la mortalité pour les patients ventilés atteints de COVID-19 possède d'excellentes propriétés diagnostiques. Néanmoins, une validation externe est nécessaire avant sa mise en œuvre généralisée.

COVID-19 , Adult , Hospital Mortality , Humans , Intensive Care Units , Pandemics , Respiration, Artificial , Retrospective Studies , Risk Factors , SARS-CoV-2
PLoS One ; 16(10): e0258368, 2021.
Article in English | MEDLINE | ID: covidwho-1468173


Effective treatment of respiratory infections continues to be a major challenge. In high doses (≥160 ppm), inhaled Nitric Oxide (iNO) has been shown to act as a broad-spectrum antimicrobial agent, including its efficacy in vitro for coronavirus family. However, the safety of prolonged in vivo implementation of high-dose iNO therapy has not been studied. Herein we aim to explore the feasibility and safety of delivering continuous high-dose iNO over an extended period of time using an in vivo animal model. Yorkshire pigs were randomized to one of the following two groups: group 1, standard ventilation; and group 2, standard ventilation + continuous iNO 160 ppm + methylene blue (MB) as intravenous bolus, whenever required, to maintain metHb <6%. Both groups were ventilated continuously for 6 hours, then the animals were weaned from sedation, mechanical ventilation and followed for 3 days. During treatment, and on the third post-operative day, physiologic assessments were performed to monitor lung function and other significative markers were assessed for potential pulmonary or systemic injury. No significant change in lung function, or inflammatory markers were observed during the study period. Both gas exchange function, lung tissue cytokine analysis and histology were similar between treated and control animals. During treatment, levels of metHb were maintained <6% by administration of MB, and NO2 remained <5 ppm. Additionally, considering extrapulmonary effects, no significant changes were observed in biochemistry markers. Our findings showed that high-dose iNO delivered continuously over 6 hours with adjuvant MB is clinically feasible and safe. These findings support the development of investigations of continuous high-dose iNO treatment of respiratory tract infections, including SARS-CoV-2.

Anti-Infective Agents/administration & dosage , Nitric Oxide/administration & dosage , Administration, Inhalation , Animals , Cytokines/analysis , Cytokines/blood , Drug Evaluation, Preclinical , Hemodynamics , Hemoglobin A/analysis , Lung/metabolism , Lung/pathology , Male , Methemoglobin/analysis , Methylene Blue/administration & dosage , Models, Animal , Nitrates/analysis , Nitrites/analysis , Swine
Respir Care ; 66(5): 814-821, 2021 May.
Article in English | MEDLINE | ID: covidwho-1395146


BACKGROUND: The growing proportion of elderly intensive care patients constitutes a public health challenge. The benefit of critical care in these patients remains unclear. We compared outcomes in elderly versus very elderly subjects receiving mechanical ventilation. METHODS: In total, 5,557 mechanically ventilated subjects were included in our post hoc retrospective analysis, a subgroup of the VENTILA study. We divided the cohort into 2 subgroups on the basis of age: very elderly subjects (age ≥ 80 y; n = 1,430), and elderly subjects (age 65-79 y; n = 4,127). A propensity score on being very elderly was calculated. Evaluation of associations with 28-d mortality was done with logistic regression analysis. RESULTS: Very elderly subjects were clinically sicker as expressed by higher SAPS II scores (53 ± 18 vs 50 ± 18, P < .001), and their rates of plateau pressure < 30 cm H2O were higher, whereas other parameters did not differ. The 28-d mortality was higher in very elderly subjects (42% vs 34%, P < .001) and remained unchanged after propensity score adjustment (adjusted odds ratio 1.31 [95% CI 1.16-1.49], P < .001). CONCLUSIONS: Age was an independent and unchangeable risk factor for death in mechanically ventilated subjects. However, survival rates of very elderly subjects were > 50%. Denial of critical care based solely on age is not justified. ( registration NCT02731898.).

Critical Illness , Respiration, Artificial , Aged , Humans , Intensive Care Units , Retrospective Studies , Risk Factors , Simplified Acute Physiology Score
Lancet Respir Med ; 9(6): 655-664, 2021 06.
Article in English | MEDLINE | ID: covidwho-1209411


The pleiotropic cytokine interleukin-6 (IL-6) has been implicated in the pathogenesis of COVID-19, but uncertainty remains about the potential benefits and harms of targeting IL-6 signalling in patients with the disease. The efficacy and safety of tocilizumab and sarilumab, which block the binding of IL-6 to its receptor, have been tested in adults with COVID-19-related acute respiratory illness in randomised trials, with important differences in trial design, characteristics of included patients, use of co-interventions, and outcome measurement scales. In this Series paper, we review the clinical and methodological heterogeneity of studies of IL-6 receptor antagonists, and consider how this heterogeneity might have influenced reported treatment effects. Timing from clinical presentation to treatment, severity of illness, and concomitant use of corticosteroids are among the factors that might have contributed to apparently inconsistent results. With an understanding of the sources of variability in these trials, available evidence could be applied to guide clinical decision making and to inform the enrichment of future studies.

Antibodies, Monoclonal, Humanized/pharmacology , COVID-19 , Clinical Trials as Topic , Receptors, Interleukin-6/antagonists & inhibitors , Antibodies, Monoclonal, Humanized/immunology , COVID-19/immunology , COVID-19/therapy , Clinical Trials as Topic/methods , Clinical Trials as Topic/statistics & numerical data , Humans , Patient Selection , Receptors, Interleukin-6/immunology , SARS-CoV-2
N Engl J Med ; 384(16): 1503-1516, 2021 04 22.
Article in English | MEDLINE | ID: covidwho-1101724


BACKGROUND: Coronavirus disease 2019 (Covid-19) is associated with immune dysregulation and hyperinflammation, including elevated interleukin-6 levels. The use of tocilizumab, a monoclonal antibody against the interleukin-6 receptor, has resulted in better outcomes in patients with severe Covid-19 pneumonia in case reports and retrospective observational cohort studies. Data are needed from randomized, placebo-controlled trials. METHODS: In this phase 3 trial, we randomly assigned patients who were hospitalized with severe Covid-19 pneumonia in a 2:1 ratio receive a single intravenous infusion of tocilizumab (at a dose of 8 mg per kilogram of body weight) or placebo. Approximately one quarter of the participants received a second dose of tocilizumab or placebo 8 to 24 hours after the first dose. The primary outcome was clinical status at day 28 on an ordinal scale ranging from 1 (discharged or ready for discharge) to 7 (death) in the modified intention-to-treat population, which included all the patients who had received at least one dose of tocilizumab or placebo. RESULTS: Of the 452 patients who underwent randomization, 438 (294 in the tocilizumab group and 144 in the placebo group) were included in the primary and secondary analyses. The median value for clinical status on the ordinal scale at day 28 was 1.0 (95% confidence interval [CI], 1.0 to 1.0) in the tocilizumab group and 2.0 (non-ICU hospitalization without supplemental oxygen) (95% CI, 1.0 to 4.0) in the placebo group (between-group difference, -1.0; 95% CI, -2.5 to 0; P = 0.31 by the van Elteren test). In the safety population, serious adverse events occurred in 103 of 295 patients (34.9%) in the tocilizumab group and in 55 of 143 patients (38.5%) in the placebo group. Mortality at day 28 was 19.7% in the tocilizumab group and 19.4% in the placebo group (weighted difference, 0.3 percentage points; 95% CI, -7.6 to 8.2; nominal P = 0.94). CONCLUSIONS: In this randomized trial involving hospitalized patients with severe Covid-19 pneumonia, the use of tocilizumab did not result in significantly better clinical status or lower mortality than placebo at 28 days. (Funded by F. Hoffmann-La Roche and the Department of Health and Human Services; COVACTA number, NCT04320615.).

Antibodies, Monoclonal, Humanized/therapeutic use , COVID-19/drug therapy , Receptors, Interleukin-6/antagonists & inhibitors , Adult , Aged , Antibodies, Monoclonal, Humanized/adverse effects , COVID-19/complications , COVID-19/mortality , COVID-19/therapy , Double-Blind Method , Female , Hospital Mortality , Hospitalization , Humans , Infusions, Intravenous , Intensive Care Units , Male , Middle Aged , Respiration, Artificial , Treatment Failure