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1.
BMJ Open ; 14(5): e081118, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38719297

RESUMO

OBJECTIVE: To characterise sex and gender-based analysis (SGBA) and diversity metric reporting, representation of female/women participants in acute care trials and temporal changes in reporting before and after publication of the 2016 Sex and Gender Equity in Research guideline. DESIGN: Systematic review. DATA SOURCES: We searched MEDLINE for trials published in five leading medical journals in 2014, 2018 and 2020. STUDY SELECTION: Trials that enrolled acutely ill adults, compared two or more interventions and reported at least one clinical outcome. DATA ABSTRACTION AND SYNTHESIS: 4 reviewers screened citations and 22 reviewers abstracted data, in duplicate. We compared reporting differences between intensive care unit (ICU) and cardiology trials. RESULTS: We included 88 trials (75 (85.2%) ICU and 13 (14.8%) cardiology) (n=111 428; 38 140 (34.2%) females/women). Of 23 (26.1%) trials that reported an SGBA, most used a forest plot (22 (95.7%)), were prespecified (21 (91.3%)) and reported a sex-by-intervention interaction with a significance test (19 (82.6%)). Discordant sex and gender terminology were found between headings and subheadings within baseline characteristics tables (17/32 (53.1%)) and between baseline characteristics tables and SGBA (4/23 (17.4%)). Only 25 acute care trials (28.4%) reported race or ethnicity. Participants were predominantly white (78.8%) and male/men (65.8%). No trial reported gendered-social factors. SGBA reporting and female/women representation did not improve temporally. Compared with ICU trials, cardiology trials reported significantly more SGBA (15/75 (20%) vs 8/13 (61.5%) p=0.005). CONCLUSIONS: Acute care trials in leading medical journals infrequently included SGBA, female/women and non-white trial participants, reported race or ethnicity and never reported gender-related factors. Substantial opportunity exists to improve SGBA and diversity metric reporting and recruitment of female/women participants in acute care trials. PROSPERO REGISTRATION NUMBER: CRD42022282565.


Assuntos
Cuidados Críticos , Humanos , Feminino , Masculino , Cuidados Críticos/estatística & dados numéricos , Publicações Periódicas como Assunto/estatística & dados numéricos , Fatores Sexuais , Fator de Impacto de Revistas , Ensaios Clínicos como Assunto , Equidade de Gênero , Cardiologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-38713090

RESUMO

Oxidative phosphorylation is regulated by mitochondrial calcium (Ca2+) in health and disease. In physiological states, Ca2+ enters via the mitochondrial Ca2+ uniporter and rapidly enhances NADH and ATP production. However, maintaining Ca2+ homeostasis is critical: insufficient Ca2+ impairs stress adaptation, while Ca2+ overload can trigger cell death. In this review, we delve into recent insights further defining the relationship between mitochondrial Ca2+ dynamics and oxidative phosphorylation. Our focus is on how such regulation affects cardiac function in health and disease, including heart failure, ischemia-reperfusion, arrhythmias, catecholaminergic polymorphic ventricular tachycardia, mitochondrial cardiomyopathies, Barth syndrome, and Friedreich's ataxia. Several themes emerge from recent data. First, mitochondrial Ca2+ regulation is critical for fuel substrate selection, metabolite import, and matching of ATP supply to demand. Second, mitochondrial Ca2+ regulates both the production and response to reactive oxygen species (ROS), and the balance between its pro- and antioxidant effects is key to how it contributes to physiological and pathological states. Third, Ca2+ exerts localized effects on the electron transport chain (ETC), not through traditional allosteric mechanisms, but rather indirectly. These effects hinge on specific transporters, such as the uniporter or the Na+-Ca2+ exchanger and may not be noticeable acutely, contributing differently to phenotypes depending on whether Ca2+ transporters are acutely or chronically modified. Perturbations in these novel relationships during disease states may either serve as compensatory mechanisms or exacerbate impairments in oxidative phosphorylation. Consequently, targeting mitochondrial Ca2+ holds promise as a therapeutic strategy for a variety of cardiac diseases characterized by contractile failure or arrhythmias.

3.
Crit Care Explor ; 6(4): e1071, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38567382

RESUMO

OBJECTIVES: We postulate that corticosteroid-related side effects in critically ill patients are similar across sepsis, acute respiratory distress syndrome (ARDS), and community-acquired pneumonia (CAP). By pooling data across all trials that have examined corticosteroids in these three acute conditions, we aim to examine the side effects of corticosteroid use in critical illness. DATA SOURCES: We performed a comprehensive search of MEDLINE, Embase, Centers for Disease Control and Prevention library of COVID research, CINAHL, and Cochrane center for trials. STUDY SELECTION: We included randomized controlled trials (RCTs) that compared corticosteroids to no corticosteroids or placebo in patients with sepsis, ARDS, and CAP. DATA EXTRACTION: We summarized data addressing the most described side effects of corticosteroid use in critical care: gastrointestinal bleeding, hyperglycemia, hypernatremia, superinfections/secondary infections, neuropsychiatric effects, and neuromuscular weakness. DATA SYNTHESIS: We included 47 RCTs (n = 13,893 patients). Corticosteroids probably have no effect on gastrointestinal bleeding (relative risk [RR], 1.08; 95% CI, 0.87-1.34; absolute risk increase [ARI], 0.3%; moderate certainty) or secondary infections (RR, 0.97; 95% CI, 0.89-1.05; absolute risk reduction, 0.5%; moderate certainty) and may have no effect on neuromuscular weakness (RR, 1.22; 95% CI, 1.03-1.45; ARI, 1.4%; low certainty) or neuropsychiatric events (RR, 1.19; 95% CI, 0.82-1.74; ARI, 0.5%; low certainty). Conversely, they increase the risk of hyperglycemia (RR, 1.21; 95% CI, 1.11-1.31; ARI, 5.4%; high certainty) and probably increase the risk of hypernatremia (RR, 1.59; 95% CI, 1.29-1.96; ARI, 2.3%; moderate certainty). CONCLUSIONS: In ARDS, sepsis, and CAP, corticosteroids are associated with hyperglycemia and probably with hypernatremia but likely have no effect on gastrointestinal bleeding or secondary infections. More data examining effects of corticosteroids, particularly on neuropsychiatric outcomes and neuromuscular weakness, would clarify the safety of this class of drugs in critical illness.

4.
Crit Care Med ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38488422

RESUMO

OBJECTIVES: To conduct a systematic review and meta-analysis assessing whether the use of antipsychotic medications in critically ill adult patients with delirium impacts patient-important outcomes. DATA SOURCES: A medical librarian searched Ovid MEDLINE, EMBASE, APA PsycInfo, and Wiley's Cochrane Library as well as clinicaltrials.gov and the World Health Organization International Clinical Trials Registry Platform up to November 2023. STUDY SELECTION: Independently and in duplicate, reviewers screened abstracts and titles for eligibility, then full text of qualifying studies. We included parallel-group randomized controlled trials (RCTs) that included critically ill adult patients with delirium. The intervention group was required to receive antipsychotic medications at any dose, whereas the control group received usual care or placebo. DATA EXTRACTION: Reviewers extracted data independently and in duplicate using a piloted abstraction form. Statistical analyses were conducted using RevMan software (version 5.4). DATA SYNTHESIS: Five RCTs ( n = 1750) met eligibility criteria. The use of antipsychotic medications compared with placebo did not increase the number of delirium- or coma-free days (mean difference 0.90 d; 95% CI, -0.32 to 2.12; moderate certainty), nor did it result in a difference in mortality, duration of mechanical ventilation, ICU, or hospital length of stay. The use of antipsychotics did not result in an increased risk of adverse events (risk ratio 1.27; 95% CI, 0.71-2.30; high certainty). Subgroup analysis of typical versus atypical antipsychotics did not identify any subgroup effect for any outcome. CONCLUSIONS: In conclusion, our systematic review and meta-analysis demonstrated with moderate certainty that there is no difference in delirium- or coma-free days when delirious critically ill adults are treated with antipsychotic medications. Further studies in the subset of patients with hyperactive delirium may be of benefit.

5.
bioRxiv ; 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38352459

RESUMO

The established clinical therapy for the treatment of acute myocardial infarction is primary percutaneous coronary intervention (PPCI) to restore blood flow to the ischemic myocardium. PPCI is effective at reperfusing the ischemic myocardium, however the rapid re-introduction of oxygenated blood also can cause ischemia-reperfusion (I/R) injury. Reperfusion injury is the culprit for up to half of the final myocardial damage, but there are no clinical interventions to reduce I/R injury. We previously demonstrated that inhibiting the lactate exporter, monocarboxylate transporter 4 (MCT4), and re-directing pyruvate towards oxidation can blunt isoproterenol-induced hypertrophy. Based on this finding, we hypothesized that the same pathway might be important during I/R. Here, we establish that the pyruvate-lactate metabolic axis plays a critical role in determining myocardial salvage following injury. Post-I/R injury, the mitochondrial pyruvate carrier (MPC), required for pyruvate oxidation, is upregulated in the surviving myocardium following I/R injury. MPC loss in cardiomyocytes caused more cell death with less myocardial salvage, which was associated with an upregulation of MCT4 in the myocardium at risk of injury. We deployed a pharmacological strategy of MCT4 inhibition with a highly selective compound (VB124) at the time of reperfusion. This strategy normalized reactive oxygen species (ROS), mitochondrial membrane potential (Δψ), and Ca 2+ , increased pyruvate entry to TCA cycle, and improved myocardial salvage and functional outcomes following I/R injury. Altogether, our data suggest that normalizing the pyruvate-lactate metabolic axis via MCT4 inhibition is a promising pharmacological strategy to mitigate I/R injury.

6.
JAMA Netw Open ; 7(2): e2356794, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38393729

RESUMO

Importance: Considerable controversy exists regarding the best spontaneous breathing trial (SBT) technique to use. Objective: To summarize trials comparing alternative SBTs. Data Sources: Several databases (MEDLINE [from inception to February 2023], the Cochrane Central Register of Controlled Trials [in February 2023], and Embase [from inception to February 2023] and 5 conference proceedings (from January 1990 to April 2023) were searched in this systematic review and meta-analysis. Study Selection: Randomized trials directly comparing SBT techniques in critically ill adults or children and reporting at least 1 clinical outcome were selected. Data Extraction and Synthesis: Paired reviewers independently screened citations, abstracted data, and assessed quality for the systematic review and meta-analysis using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA guidelines). Data were pooled using random-effects models. Main Outcomes and Measures: Primary outcomes included SBT success, extubation success, and reintubation. Results: The systematic review and meta-analysis identified 40 trials that included 6716 patients. Low-quality evidence (14 trials [n = 4459]) suggested that patients were not more likely to pass a pressure support (PS) compared with a T-piece SBT (risk ratio [RR], 1.04; 95% CI, 0.97-1.11; P = .31; I2 = 73%), unless 1 outlier trial accounting for all heterogeneity was excluded (RR, 1.09; 95% CI, 1.06-1.12; P < .001; I2 = 0% [13 trials; n = 3939]; moderate-quality evidence), but were significantly more likely to be successfully extubated (RR, 1.07; 95% CI, 1.04-1.10; P < .001; I2 = 0%; 16 trials [n = 4462]; moderate-quality evidence). Limited data (5 trials [n = 502]) revealed that patients who underwent automatic tube compensation/continuous positive airway pressure compared with PS SBTs had a significantly higher successful extubation rate (RR, 1.10; 95% CI, 1.00-1.21; P = .04; I2 = 0% [low-quality evidence]). Compared with T-piece SBTs, high-flow oxygen SBTs (3 trials [n = 386]) had significantly higher successful extubation (RR, 1.06; 95% CI, 1.00-1.11; P = .04; I2 = 0%) and lower reintubation (RR, 0.37; 95% CI, 0.21-0.65; P = <.001; I2 = 0% [both low-quality evidence]) rates. Credible subgroup effects were not found. Conclusions and Relevance: In this systematic review and meta-analysis, the findings suggest that patients undergoing PS compared with T-piece SBTs were more likely to be extubated successfully and more likely to pass an SBT, after exclusion of an outlier trial. Pressure support SBTs were not associated with increased risk of reintubation. Future trials should compare SBT techniques that maximize differences in inspiratory support.


Assuntos
Estado Terminal , Desmame do Respirador , Adulto , Criança , Humanos , Estado Terminal/terapia , Desmame do Respirador/métodos , Oxigênio , Pressão Positiva Contínua nas Vias Aéreas , Intubação Intratraqueal
8.
Crit Care Med ; 52(5): e219-e233, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38240492

RESUMO

RATIONALE: New evidence is available examining the use of corticosteroids in sepsis, acute respiratory distress syndrome (ARDS) and community-acquired pneumonia (CAP), warranting a focused update of the 2017 guideline on critical illness-related corticosteroid insufficiency. OBJECTIVES: To develop evidence-based recommendations for use of corticosteroids in hospitalized adults and children with sepsis, ARDS, and CAP. PANEL DESIGN: The 22-member panel included diverse representation from medicine, including adult and pediatric intensivists, pulmonologists, endocrinologists, nurses, pharmacists, and clinician-methodologists with expertise in developing evidence-based Clinical Practice Guidelines. We followed Society of Critical Care Medicine conflict of interest policies in all phases of the guideline development, including task force selection and voting. METHODS: After development of five focused Population, Intervention, Control, and Outcomes (PICO) questions, we conducted systematic reviews to identify the best available evidence addressing each question. We evaluated the certainty of evidence using the Grading of Recommendations Assessment, Development, and Evaluation approach and formulated recommendations using the evidence-to-decision framework. RESULTS: In response to the five PICOs, the panel issued four recommendations addressing the use of corticosteroids in patients with sepsis, ARDS, and CAP. These included a conditional recommendation to administer corticosteroids for patients with septic shock and critically ill patients with ARDS and a strong recommendation for use in hospitalized patients with severe CAP. The panel also recommended against high dose/short duration administration of corticosteroids for septic shock. In response to the final PICO regarding type of corticosteroid molecule in ARDS, the panel was unable to provide specific recommendations addressing corticosteroid molecule, dose, and duration of therapy, based on currently available evidence. CONCLUSIONS: The panel provided updated recommendations based on current evidence to inform clinicians, patients, and other stakeholders on the use of corticosteroids for sepsis, ARDS, and CAP.


Assuntos
Síndrome do Desconforto Respiratório , Sepse , Choque Séptico , Adulto , Humanos , Criança , Choque Séptico/tratamento farmacológico , Sepse/tratamento farmacológico , Corticosteroides/uso terapêutico , Síndrome do Desconforto Respiratório/tratamento farmacológico , Cuidados Críticos , Estado Terminal/terapia
9.
Crit Care Explor ; 6(1): e1000, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38250247

RESUMO

OBJECTIVES: To perform a systematic review and meta-analysis to assess the efficacy and safety of corticosteroids in patients with sepsis. DATA SOURCES: We searched PubMed, Embase, and the Cochrane Library, up to January 10, 2023. STUDY SELECTION: We included randomized controlled trials (RCTs) comparing corticosteroids with placebo or standard care with sepsis. DATA EXTRACTION: The critical outcomes of interest included mortality, shock reversal, length of stay in the ICU, and adverse events. DATA ANALYSIS: We performed both a pairwise and dose-response meta-analysis to evaluate the effect of different corticosteroid doses on outcomes. We used Grading of Recommendations Assessment, Development and Evaluation to assess certainty in pooled estimates. DATA SYNTHESIS: We included 45 RCTs involving 9563 patients. Corticosteroids probably reduce short-term mortality (risk ratio [RR], 0.93; 95% CI, 0.88-0.99; moderate certainty) and increase shock reversal at 7 days (RR, 1.24; 95% CI, 1.11-1.38; high certainty). Corticosteroids may have no important effect on duration of ICU stay (mean difference, -0.6 fewer days; 95% CI, 1.48 fewer to 0.27 more; low certainty); however, probably increase the risk of hyperglycemia (RR, 1.13; 95% CI, 1.08-1.18; moderate certainty) and hypernatremia (RR, 1.64; 95% CI, 1.32-2.03; moderate certainty) and may increase the risk of neuromuscular weakness (RR, 1.21; 95% CI, 1.01-1.45; low certainty). The dose-response analysis showed a reduction in mortality with corticosteroids with optimal dosing of approximately 260 mg/d of hydrocortisone (RR, 0.90; 95% CI, 0.83-0.98) or equivalent. CONCLUSIONS: We found that corticosteroids may reduce mortality and increase shock reversal but they may also increase the risk of hyperglycemia, hypernatremia, and neuromuscular weakness. The dose-response analysis indicates optimal dosing is around 260 mg/d of hydrocortisone or equivalent.

10.
Can J Anaesth ; 71(1): 118-126, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37884773

RESUMO

PURPOSE: We sought to understand the beliefs and practices of Canadian intensivists regarding their use of ketamine as a sedative in critically ill patients and to gauge their interest in a randomized controlled trial (RCT) examining its use in the intensive care unit (ICU). METHODS: We designed and validated an electronic self-administered survey examining the use of ketamine as a sedative infusion for ICU patients. We surveyed 400 physician members of the Canadian Critical Care Society (CCCS) via email between February and April 2022 and sent three reminders at two-week intervals. The survey was redistributed in January 2023 to improve the response rate. RESULTS: We received 87/400 (22%) completed questionnaires. Most respondents reported they rarely use ketamine as a continuous infusion for sedation or analgesia in the ICU (52/87, 58%). Physicians reported the following conditions would make them more likely to use ketamine: asthma exacerbation (73/87, 82%), tolerance to opioids (68/87, 77%), status epilepticus (44/87, 50%), and severe acute respiratory distress syndrome (33/87, 38%). Concern for side-effects that limited respondents' use of ketamine include adverse psychotropic effects (61/87, 69%) and delirium (47/87, 53%). The majority of respondents agreed there is need for an RCT to evaluate ketamine as a sedative infusion in the ICU (62/87, 71%). CONCLUSION: This survey of Canadian intensivists illustrates that use of ketamine as a continuous infusion for sedation is limited, and is at least partly driven by concerns of adverse psychotropic effects. Canadian physicians endorse the need for a trial investigating the safety and efficacy of ketamine as a sedative for critically ill patients.


RéSUMé: OBJECTIF: Nous avons cherché à comprendre les croyances et les pratiques des intensivistes pratiquant au Canada concernant leur utilisation de la kétamine comme sédatif chez la patientèle gravement malade et à évaluer leur intérêt pour une étude randomisée contrôlée (ERC) examinant son utilisation à l'unité de soins intensifs (USI). MéTHODE: Nous avons mis au point et validé un sondage électronique auto-administré examinant l'utilisation de la kétamine comme perfusion sédative pour les patient·es aux soins intensifs. Nous avons envoyé le sondage à 400 médecins membres de la Société canadienne de soins intensifs (SCCC) par courriel entre février et avril 2022 et envoyé trois rappels à intervalles de deux semaines. Le sondage a été redistribué en janvier 2023 afin d'améliorer le taux de réponse. RéSULTATS: Nous avons reçu 87 questionnaires remplis sur 400 (22 %). La plupart des personnes répondantes ont déclaré qu'elles utilisaient rarement la kétamine en perfusion continue pour la sédation ou l'analgésie à l'USI (52/87, 58 %). Les médecins ont déclaré que les conditions suivantes les rendraient plus susceptibles d'utiliser de la kétamine : une exacerbation de l'asthme (73/87, 82 %), une tolérance aux opioïdes (68/87, 77 %), un état de mal épileptique (44/87, 50 %) et un syndrome de détresse respiratoire aigu (33/87, 38 %). Les inquiétudes quant aux effets secondaires qui ont limité l'utilisation de la kétamine par les répondant·es comprennent les effets psychotropes indésirables (61/87, 69 %) et le delirium (47/87, 53 %). La majorité des personnes répondantes étaient d'accord qu'une ERC est nécessaire pour évaluer la kétamine en tant que perfusion sédative à l'USI (62/87, 71 %). CONCLUSION: Cette enquête menée auprès d'intensivistes au Canada montre que l'utilisation de la kétamine comme perfusion continue pour la sédation est limitée, au moins en partie en raison d'inquiétudes liées aux effets psychotropes indésirables. Les médecins pratiquant au Canada reconnaissent la nécessité d'une étude sur l'innocuité et l'efficacité de la kétamine comme sédatif pour la patientèle gravement malade.


Assuntos
Ketamina , Humanos , Ketamina/efeitos adversos , Estado Terminal , Canadá , Unidades de Terapia Intensiva , Hipnóticos e Sedativos , Inquéritos e Questionários
11.
Am J Respir Crit Care Med ; 209(1): 24-36, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38032683

RESUMO

Background: This document updates previously published Clinical Practice Guidelines for the management of patients with acute respiratory distress syndrome (ARDS), incorporating new evidence addressing the use of corticosteroids, venovenous extracorporeal membrane oxygenation, neuromuscular blocking agents, and positive end-expiratory pressure (PEEP). Methods: We summarized evidence addressing four "PICO questions" (patient, intervention, comparison, and outcome). A multidisciplinary panel with expertise in ARDS used the Grading of Recommendations, Assessment, Development, and Evaluation framework to develop clinical recommendations. Results: We suggest the use of: 1) corticosteroids for patients with ARDS (conditional recommendation, moderate certainty of evidence), 2) venovenous extracorporeal membrane oxygenation in selected patients with severe ARDS (conditional recommendation, low certainty of evidence), 3) neuromuscular blockers in patients with early severe ARDS (conditional recommendation, low certainty of evidence), and 4) higher PEEP without lung recruitment maneuvers as opposed to lower PEEP in patients with moderate to severe ARDS (conditional recommendation, low to moderate certainty), and 5) we recommend against using prolonged lung recruitment maneuvers in patients with moderate to severe ARDS (strong recommendation, moderate certainty). Conclusions: We provide updated evidence-based recommendations for the management of ARDS. Individual patient and illness characteristics should be factored into clinical decision making and implementation of these recommendations while additional evidence is generated from much-needed clinical trials.


Assuntos
Bloqueadores Neuromusculares , Síndrome do Desconforto Respiratório , Adulto , Humanos , Corticosteroides/uso terapêutico , Pulmão , Bloqueadores Neuromusculares/uso terapêutico , Respiração com Pressão Positiva , Síndrome do Desconforto Respiratório/tratamento farmacológico
12.
bioRxiv ; 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38014208

RESUMO

Mitochondrial ion channels are essential for energy production and cell survival. To avoid depleting the electrochemical gradient used for ATP synthesis, channels so far described in the mitochondrial inner membrane open only briefly, are highly ion-selective, have restricted tissue distributions, or have small currents. Here, we identify a mitochondrial inner membrane conductance that has strikingly different behavior from previously described channels. It is expressed ubiquitously, and transports cations non-selectively, producing a large, up to nanoampere-level, current. The channel does not lead to inner membrane uncoupling during normal physiology because it only becomes active at depolarized voltages. It is inhibited by external Ca2+, corresponding to the intermembrane space, as well as amiloride. This large, ubiquitous, non-selective, amiloride-sensitive (LUNA) current appears most active when expression of the mitochondrial calcium uniporter is minimal, such as in the heart. In this organ, we find that LUNA current magnitude increases two- to threefold in multiple mouse models of injury, an effect also seen in cardiac mitochondria from human patients with heart failure with reduced ejection fraction. Taken together, these features lead us to speculate that LUNA current may arise from an essential protein that acts as a transporter under physiological conditions, but becomes a channel under conditions of mitochondrial stress and depolarization.

13.
Biochem Soc Trans ; 51(4): 1661-1673, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37641565

RESUMO

While mitochondria oxidative phosphorylation is broadly regulated, the impact of mitochondrial Ca2+ on substrate flux under both physiological and pathological conditions is increasingly being recognized. Under physiologic conditions, mitochondrial Ca2+ enters through the mitochondrial Ca2+ uniporter and boosts ATP production. However, maintaining Ca2+ homeostasis is crucial as too little Ca2+ inhibits adaptation to stress and Ca2+ overload can trigger cell death. In this review, we discuss new insights obtained over the past several years expanding the relationship between mitochondrial Ca2+ and oxidative phosphorylation, with most data obtained from heart, liver, or skeletal muscle. Two new themes are emerging. First, beyond boosting ATP synthesis, Ca2+ appears to be a critical determinant of fuel substrate choice between glucose and fatty acids. Second, Ca2+ exerts local effects on the electron transport chain indirectly, not via traditional allosteric mechanisms. These depend critically on the transporters involved, such as the uniporter or the Na+-Ca2+ exchanger. Alteration of these new relationships during disease can be either compensatory or harmful and suggest that targeting mitochondrial Ca2+ may be of therapeutic benefit during diseases featuring impairments in oxidative phosphorylation.


Assuntos
Cálcio , Fosforilação Oxidativa , Morte Celular , Mitocôndrias , Trifosfato de Adenosina
14.
Crit Care Explor ; 5(7): e0938, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37396930

RESUMO

While opioids are part of usual care for analgesia in the ICU, there are concerns regarding excess use. This is a systematic review of nonsteroidal anti-inflammatory drugs (NSAIDs) use in postoperative critical care adult patients. DATA SOURCES: We searched Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, trial registries, Google Scholar, and relevant systematic reviews through March 2023. STUDY SELECTION: Titles, abstracts, and full texts were reviewed independently and induplicate by two investigators to identify eligible studies. We included randomized control trials (RCTs) that compared NSAIDs alone or as an adjunct to opioids for systemic analgesia. The primary outcome was opioid utilization. DATA EXTRACTION: In duplicate, investigators independently extracted study characteristics, patient demographics, intervention details, and outcomes of interest using predefined abstraction forms. Statistical analyses were conducted using Review Manager software Version 5.4. (The Cochrane Collaboration, Copenhagen, Denmark). DATA SYNTHESIS: We included 15 RCTs (n = 1,621 patients) for admission to the ICU for postoperative management after elective procedures. Adjunctive NSAID therapy to opioids reduced 24-hour oral morphine equivalent consumption by 21.4 mg (95% CI, 11.8-31.0 mg reduction; high certainty) and probably reduced pain scores (measured by Visual Analog Scale) by 6.1 mm (95% CI, 12.2 decrease to 0.1 increase; moderate certainty). Adjunctive NSAID therapy probably had no impact on the duration of mechanical ventilation (1.6 hr reduction; 95% CI, 0.4 hr to 2.7 reduction; moderate certainty) and may have no impact on ICU length of stay (2.1 hr reduction; 95% CI, 6.1 hr reduction to 2.0 hr increase; low certainty). Variability in reporting adverse outcomes (e.g., gastrointestinal bleeding, acute kidney injury) precluded their meta-analysis. CONCLUSIONS: In postoperative critical care adult patients, systemic NSAIDs reduced opioid use and probably reduced pain scores. However, the evidence is uncertain for the duration of mechanical ventilation or ICU length of stay. Further research is required to characterize the prevalence of NSAID-related adverse outcomes.

16.
Basic Res Cardiol ; 118(1): 20, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37212935

RESUMO

SMYD1, a striated muscle-specific lysine methyltransferase, was originally shown to play a key role in embryonic cardiac development but more recently we demonstrated that loss of Smyd1 in the murine adult heart leads to cardiac hypertrophy and failure. However, the effects of SMYD1 overexpression in the heart and its molecular function in the cardiomyocyte in response to ischemic stress are unknown. In this study, we show that inducible, cardiomyocyte-specific overexpression of SMYD1a in mice protects the heart from ischemic injury as seen by a > 50% reduction in infarct size and decreased myocyte cell death. We also demonstrate that attenuated pathological remodeling is a result of enhanced mitochondrial respiration efficiency, which is driven by increased mitochondrial cristae formation and stabilization of respiratory chain supercomplexes within the cristae. These morphological changes occur concomitant with increased OPA1 expression, a known driver of cristae morphology and supercomplex formation. Together, these analyses identify OPA1 as a novel downstream target of SMYD1a whereby cardiomyocytes upregulate energy efficiency to dynamically adapt to the energy demands of the cell. In addition, these findings highlight a new epigenetic mechanism by which SMYD1a regulates mitochondrial energetics and functions to protect the heart from ischemic injury.


Assuntos
Músculo Esquelético , Miócitos Cardíacos , Animais , Camundongos , Cardiomegalia/metabolismo , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Miócitos Cardíacos/metabolismo
17.
Crit Care Explor ; 5(4): e0892, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37007904

RESUMO

To evaluate the efficacy and cost-effectiveness of high-flow nasal cannula (HFNC) when compared with noninvasive positive pressure ventilation (NIPPV) in patients with acute hypoxic respiratory failure (AHRF). DATA SOURCES: We performed a comprehensive search of MEDLINE, Embase, CINAHL, the Cochrane library, and the international Health Technology Assessment database from inception to September 14, 2022. STUDY SELECTION: We included randomized control studies that compared HFNC to NIPPV in adult patients with AHRF. For clinical outcomes, we included only parallel group and crossover randomized control trials (RCTs). For economic outcomes, we included any study design that evaluated cost-effectiveness, cost-utility, or cost benefit analyses. DATA EXTRACTION: Clinical outcomes of interest included intubation, mortality, ICU and hospital length of stay (LOS), and patient-reported dyspnea. Economic outcomes of interest included costs, cost-effectiveness, and cost-utility. DATA SYNTHESIS: We included nine RCTs (n = 1,539 patients) and one cost-effectiveness study. Compared with NIPPV, HFNC may have no effect on the need for intubation (relative risk [RR], 0.93; 95% CI, 0.69-1.27; low certainty) and an uncertain effect on mortality (RR, 0.84; 95% CI, 0.59-1.21; very low certainty). In subgroup analysis, NIPPV delivered through the helmet interface-as opposed to the facemask interface-may reduce intubation compared with HFNC (p = 0.006; moderate credibility of subgroup effect). There was no difference in ICU or hospital LOS (both low certainty) and an uncertain effect on patient-reported dyspnea (very low certainty). We could make no conclusions regarding the cost-effectiveness of HFNC compared with NIPPV. CONCLUSIONS: HFNC and NIPPV may be similarly effective at reducing the need for intubation with an uncertain effect on mortality in hospitalized patients with hypoxemic respiratory failure. More research evaluating different interfaces in varying clinical contexts is needed to improve generalizability and precision of findings.

18.
J Gen Intern Med ; 38(11): 2593-2606, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37076606

RESUMO

INTRODUCTION: International guidelines provide heterogenous guidance on use of corticosteroids for community-acquired pneumonia (CAP). METHODS: We performed a systematic review of randomized controlled trials examining corticosteroids in hospitalized adult patients with suspected or probable CAP. We performed a pairwise and dose-response meta-analysis using the restricted maximum likelihood (REML) heterogeneity estimator. We assessed the certainty of the evidence using GRADE methodology and the credibility of subgroups using the ICEMAN tool. RESULTS: We identified 18 eligible studies that included 4661 patients. Corticosteroids probably reduce mortality in more severe CAP (RR 0.62 [95% CI 0.45 to 0.85]; moderate certainty) with possibly no effect in less severe CAP (RR 1.08 [95% CI 0.83 to 1.42]; low certainty). We found a non-linear dose-response relationship between corticosteroids and mortality, suggesting an optimal dose of approximately 6 mg of dexamethasone (or equivalent) for a duration of therapy of 7 days (RR 0.44 [95% 0.30 to 0.66]). Corticosteroids probably reduce the risk of requiring invasive mechanical ventilation (RR 0.56 [95% CI 0.42 to 74] and probably reduce intensive care unit (ICU) admission (RR 0.65 [95% CI 0.43 to 0.97]) (both moderate certainty). Corticosteroids may reduce the duration of hospitalization and ICU stay (both low certainty). Corticosteroids may increase the risk of hyperglycemia (RR 1.76 [95% CI 1.46 to 2.14]) (low certainty). CONCLUSION: Moderate certainty evidence indicates that corticosteroids reduce mortality in patients with more severe CAP, the need for invasive mechanical ventilation, and ICU admission.


Assuntos
Corticosteroides , Pneumonia Bacteriana , Adulto , Humanos , Corticosteroides/uso terapêutico , Hospitalização , Respiração Artificial , Unidades de Terapia Intensiva , Pneumonia Bacteriana/tratamento farmacológico
19.
Front Med (Lausanne) ; 10: 1075797, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36824605

RESUMO

Purpose: The helmet is a novel interface for delivering non-invasive ventilation (NIV). We conducted a case series to characterize introduction of the helmet interface in both COVID and non-COVID patients at two-centres. Methods: We enrolled all patients with respiratory failure admitted to the Juravinski Hospital (Hamilton, Canada) and St. Joseph's Health Center (Syracuse, New York) between November 1, 2020 and June 30, 2021 who used the helmet interface (Intersurgical StarMed) as part of this introduction into clinical practice. We collected patient demographics, reason for respiratory failure, NIV settings, device-related complications and outcomes. We report respiratory therapist's initial experiences with the helmet using descriptive results. Results: We included 16 patients with a mean age of 64.3 ± 10.9 years. The most common etiology for respiratory failure was pneumonia (81.3%). The median duration of NIV during the ICU admission was 67.5 (15.3, 80.8) hours, with a mean maximum PS of 13.9 ± 6.6 cm H2O and a mean maximum PEEP of 10.4 ± 5.1 cm H20. Three patients (18.7%) did not tolerate the helmet. Ten (62.5%) patients ultimately required intubation, and 7 (43.4%) patients died while in the ICU. The most common reason for intubation was worsening hypoxia (70%). No adverse events related to the helmet were recorded. Conclusion: Over the 8-month period of this study, we found that the helmet was well tolerated in over 80% of patients, although, more than half ultimately required intubation. Randomized controlled trials with this device are required to fully assess the efficacy of this interface.

20.
Sci Adv ; 9(8): eade7864, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36827367

RESUMO

Thermogenesis by uncoupling protein 1 (UCP1) is one of the primary mechanisms by which brown adipose tissue (BAT) increases energy expenditure. UCP1 resides in the inner mitochondrial membrane (IMM), where it dissipates membrane potential independent of adenosine triphosphate (ATP) synthase. Here, we provide evidence that phosphatidylethanolamine (PE) modulates UCP1-dependent proton conductance across the IMM to modulate thermogenesis. Mitochondrial lipidomic analyses revealed PE as a signature molecule whose abundance bidirectionally responds to changes in thermogenic burden. Reduction in mitochondrial PE by deletion of phosphatidylserine decarboxylase (PSD) made mice cold intolerant and insensitive to ß3 adrenergic receptor agonist-induced increase in whole-body oxygen consumption. High-resolution respirometry and fluorometry of BAT mitochondria showed that loss of mitochondrial PE specifically lowers UCP1-dependent respiration without compromising electron transfer efficiency or ATP synthesis. These findings were confirmed by a reduction in UCP1 proton current in PE-deficient mitoplasts. Thus, PE performs a previously unknown role as a temperature-responsive rheostat that regulates UCP1-dependent thermogenesis.


Assuntos
Fosfatidiletanolaminas , Prótons , Camundongos , Animais , Proteína Desacopladora 1/metabolismo , Fosfatidiletanolaminas/metabolismo , Mitocôndrias/metabolismo , Termogênese , Obesidade/metabolismo , Trifosfato de Adenosina/metabolismo , Camundongos Knockout
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