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Breast Surgery

Tuesday, 22 October 2019

2019 IDSA Guidelines for Community Acquired Pneumonia in Adults: To HCAP, we just say fare thee well

by Jon-Emile S. Kenny 

New guidelines from the American Thoracic Society/Infectious Disease Society of America


The last American Thoracic Society/Infectious Disease Society of America [ATS/IDSA] guidelines on community acquired pneumonia [CAP] were published in 2007; it seems hard to remember the world at that time – free from the tweeting of medical information, free from the tweeting of world leaders.  Is 2019 better for everyone?  Worse?  For some?

The 2019 inception of the ATS/IDSA guidelines for CAP reserves a more pragmatic approach than its screed-like predecessor – clearly defining 16 high-yield clinical questions and answering them under the direction of the PICO framework.  Critically, the current recommendations make clear that:

This guideline focuses on patients in the United States who have not recently completed foreign travel…. on adults who do not have an immunocompromising condition, such as inherited or acquired immune deficiency or drug-induced neutropenia, including patients actively receiving cancer chemotherapy, patients infected with HIV with suppressed CD4 counts, and solid organ or bone marrow transplant recipients.”

Accordingly, and as mentioned in the 2016 update on hospital-acquired and ventilator-associated pneumonia, guidelines remain guidelines.  They are not sacrosanct; they needn’t be followed without falter in all patients, always; clinical judgement and individual patient characteristics are also guiding principles.  In my humble opinion, the only deontological imperative is that you are informed and the current IDSA CAP guidelines are an excellent fund of rational, practical information.

RBC Transfusion Strategies in the ICU: A Concise Review

by Cable, Casey A.; Razavi, Seyed Amirhossein; Roback, John D.; Murphy, David J. 

Objectives: To critically assess available high-level clinical studies regarding RBC transfusion strategies, with a focus on hemoglobin transfusion thresholds in the ICU.
Data Sources: Source data were obtained from a PubMed literature review.
Study Selection: English language studies addressing RBC transfusions in the ICU with a focus on the most recent relevant studies.
Data Extraction: Relevant studies were reviewed and the following aspects of each study were identified, abstracted, and analyzed: study design, methods, results, and implications for critical care practice.
Data Synthesis: Approximately 30–50% of ICU patients receive a transfusion during their hospitalization with anemia being the indication for 75% of transfusions. A significant body of clinical research evidence supports using a restrictive transfusion strategy (e.g., hemoglobin threshold < 7 g/dL) compared with a more liberal approach (e.g., hemoglobin threshold < 10 g/dL). A restrictive strategy (hemoglobin < 7 g/dL) is recommended in patients with sepsis and gastrointestinal bleeds. A slightly higher restrictive threshold is recommended in cardiac surgery (hemoglobin < 7.5 g/dL) and stable cardiovascular disease (hemoglobin < 8 g/dL). Although restrictive strategies are generally supported in hematologic malignancies, acute neurologic injury, and burns, more definitive studies are needed, including acute coronary syndrome. Massive transfusion protocols are the mainstay of treatment for hemorrhagic shock; however, the exact RBC to fresh frozen plasma ratio is still unclear. There are also emerging complimentary practices including nontransfusion strategies to avoid and treat anemia and the reemergence of whole blood transfusion.
Conclusions: The current literature supports the use of restrictive transfusion strategies in the majority of critically ill populations. Continued studies of optimal transfusion strategies in various patient populations, coupled with the integration of novel complementary ICU practices, will continue to enhance our ability to treat critically ill patients.

Impact of natural light exposure on delirium burden in adult patients receiving invasive mechanical ventilation in the ICU: a prospective study

by Roland Smonig, Eric Magalhaes, Lila Bouadma, Olivier Andremont, Etienne de Montmollin, Fatiah Essardy, Bruno Mourvillier, Jordane Lebut, Claire Dupuis, Mathilde Neuville, Mathilde Lermuzeaux, Jean-François Timsit and Romain Sonneville

Annals of Intensive Care volume 9, Article number: 120 (2019)

To determine whether potential exposure to natural light via windows is associated with reduced delirium burden in critically ill patients admitted to the ICU in a single room.
Prospective single-center study.
Medical ICU of a university hospital, Paris, France.
Adult patients receiving invasive mechanical ventilation.
Consecutive patients admitted to a single room with (LIGHT group) or without (DARK group) exposure to natural light via windows were evaluated for delirium. The primary endpoint was the incidence of delirium. Main secondary endpoints included incidence of severe agitation intervened with antipsychotics and incidence of hallucinations.
A total of 195 patients were included (LIGHT group: n = 110; DARK group: n = 85). The incidence of delirium was similar in the LIGHT group and the DARK group (64% vs. 71%; relative risk (RR) 0.89, 95% CI 0.73–1.09). Compared with the DARK group, patients from the LIGHT group were less likely to be intervened with antipsychotics for agitation episodes (13% vs. 25%; RR 0.52, 95% CI 0.27–0.98) and had less frequent hallucinations (11% vs. 22%; RR 0.49, 95% CI 0.24–0.98). In multivariate logistic regression analysis, natural light exposure was independently associated with a reduced risk of agitation episodes intervened with antipsychotics (adjusted odds ratio = 0.39; 95% CI 0.17–0.88).
Admission to a single room with potential exposure to natural light via windows was not associated with reduced delirium burden, as compared to admission to a single room without windows. However, natural light exposure was associated with a reduced risk of agitation episodes and hallucinations.

Emergency Department to ICU Time Is Associated With Hospital Mortality: A Registry Analysis of 14,788 Patients From Six University Hospitals in The Netherlands*

Groenland, Carline N. L.; Termorshuizen, Fabian; Rietdijk, Wim J. R.; van den Brule, Judith; Dongelmans, Dave A.; de Jonge, Evert; de Lange, Dylan W.; de Smet, Anne Marie G. A.; de Keizer, Nicolette F.; Weigel, Joachim D.; Jewbali, Lucia S. D.; Boersma, Eric; den Uil, Corstiaan A.

Objectives: Prolonged emergency department to ICU waiting time may delay intensive care treatment, which could negatively affect patient outcomes. The aim of this study was to investigate whether emergency department to ICU time is associated with hospital mortality.
Design, Setting, and Patients: We conducted a retrospective observational cohort study using data from the Dutch quality registry National Intensive Care Evaluation. Adult patients admitted to the ICU directly from the emergency department in six university hospitals, between 2009 and 2016, were included. Using a logistic regression model, we investigated the crude and adjusted (for disease severity; Acute Physiology and Chronic Health Evaluation IV probability) odds ratios of emergency department to ICU time on mortality. In addition, we assessed whether the Acute Physiology and Chronic Health Evaluation IV probability modified the effect of emergency department to ICU time on mortality. Secondary outcomes were ICU, 30-day, and 90-day mortality.
Interventions: None.
Measurements and Main Results: A total of 14,788 patients were included. The median emergency department to ICU time was 2.0 hours (interquartile range, 1.3–3.3 hr). Emergency department to ICU time was correlated to adjusted hospital mortality (p < 0.002), in particular in patients with the highest Acute Physiology and Chronic Health Evaluation IV probability and long emergency department to ICU time quintiles: odds ratio, 1.29; 95% CI, 1.02–1.64 (2.4–3.7 hr) and odds ratio, 1.54; 95% CI, 1.11–2.14 (> 3.7 hr), both compared with the reference category (< 1.2 hr). For 30-day and 90-day mortality, we found similar results. However, emergency department to ICU time was not correlated to adjusted ICU mortality (p = 0.20).
Conclusions: Prolonged emergency department to ICU time (> 2.4 hr) is associated with increased hospital mortality after ICU admission, mainly driven by patients who had a higher Acute Physiology and Chronic Health Evaluation IV probability. We hereby provide evidence that rapid admission of the most critically ill patients to the ICU might reduce hospital mortality.

A Machine Learning Algorithm to Predict Severe Sepsis and Septic Shock: Development, Implementation, and Impact on Clinical Practice*

by Giannini, Heather M.; Ginestra, Jennifer C.; Chivers, Corey; Draugelis, Michael; Hanish, Asaf; Schweickert, William D.; Fuchs, Barry D.; Meadows, Laurie; Lynch, Michael; Donnelly, Patrick J.; Pavan, Kimberly; Fishman, Neil O.; Hanson, C. William III; Umscheid, Craig A

Objectives: Develop and implement a machine learning algorithm to predict severe sepsis and septic shock and evaluate the impact on clinical practice and patient outcomes.
Design: Retrospective cohort for algorithm derivation and validation, pre-post impact evaluation. Setting: Tertiary teaching hospital system in Philadelphia, PA.
Patients: All non-ICU admissions; algorithm derivation July 2011 to June 2014 (n = 162,212); algorithm validation October to December 2015 (n = 10,448); silent versus alert comparison January 2016 to February 2017 (silent n = 22,280; alert n = 32,184).
Interventions: A random-forest classifier, derived and validated using electronic health record data, was deployed both silently and later with an alert to notify clinical teams of sepsis prediction. Measurement and Main Result: Patients identified for training the algorithm were required to have International Classification of Diseases, 9th Edition codes for severe sepsis or septic shock and a positive blood culture during their hospital encounter with either a lactate greater than 2.2 mmol/L or a systolic blood pressure less than 90 mm Hg. The algorithm demonstrated a sensitivity of 26% and specificity of 98%, with a positive predictive value of 29% and positive likelihood ratio of 13. The alert resulted in a small statistically significant increase in lactate testing and IV fluid administration. There was no significant difference in mortality, discharge disposition, or transfer to ICU, although there was a reduction in time-to-ICU transfer.
Conclusions: Our machine learning algorithm can predict, with low sensitivity but high specificity, the impending occurrence of severe sepsis and septic shock. Algorithm-generated predictive alerts modestly impacted clinical measures. Next steps include describing clinical perception of this tool and optimizing algorithm design and delivery.

Major asthma guideline update: ICS-LABA as-needed replaces albuterol

In their first major update in 30 years, newly published asthma guidelines recommend significant changes to the way physicians treat millions of patients diagnosed with asthma. The Global Initiative for Asthma (GINA) now advises that, in general:  Most people with asthma can now be prescribed just one inhaler: an inhaled corticosteroid-and-long-acting beta agonist (ICS-LABA) combination [... read more]

Physiological effects of high-flow oxygen in tracheostomized patients

by Daniele Natalini, Domenico L. Grieco, Maria Teresa Santantonio, Lucrezia Mincione, Flavia Toni, Gian Marco Anzellotti, Davide Eleuteri, Pierluigi Di Giannatale, Massimo Antonelli and Salvatore Maurizio Maggiore

Annals of Intensive Care volume 9, Article number: 114 (2019)

High-flow oxygen therapy via nasal cannula (HFOTNASAL) increases airway pressure, ameliorates oxygenation and reduces work of breathing. High-flow oxygen can be delivered through tracheostomy (HFOTTRACHEAL), but its physiological effects have not been systematically described. We conducted a cross-over study to elucidate the effects of increasing flow rates of HFOTTRACHEAL on gas exchange, respiratory rate and endotracheal pressure and to compare lower airway pressure produced by HFOTNASAL and HFOTTRACHEAL.
Twenty-six tracheostomized patients underwent standard oxygen therapy through a conventional heat and moisture exchanger, and then HFOTTRACHEAL through a heated humidifier, with gas flow set at 10, 30 and 50 L/min. Each step lasted 30 min; gas flow sequence during HFOTTRACHEAL was randomized. In five patients, measurements were repeated during HFOTTRACHEAL before tracheostomy decannulation and immediately after during HFOTNASAL. In each step, arterial blood gases, respiratory rate, and tracheal pressure were measured.
During HFOTTRACHEAL, PaO2/FiO2 ratio and tracheal expiratory pressure slightly increased proportionally to gas flow. The mean [95% confidence interval] expiratory pressure raise induced by 10-L/min increase in flow was 0.2 [0.1–0.2] cmH2O (ρ = 0.77, p < 0.001). Compared to standard oxygen, HFOTTRACHEAL limited the negative inspiratory swing in tracheal pressure; at 50 L/min, but not with other settings, HFOTTRACHEAL increased mean tracheal expiratory pressure by (mean difference [95% CI]) 0.4 [0.3–0.6] cmH2O, peak tracheal expiratory pressure by 0.4 [0.2–0.6] cmH2O, improved PaO2/FiO2 ratio by 40 [8–71] mmHg, and reduced respiratory rate by 1.9 [0.3–3.6] breaths/min without PaCO2 changes. As compared to HFOTTRACHEAL, HFOTNASAL produced higher tracheal mean and peak expiratory pressure (at 50 L/min, mean difference [95% CI]: 3 [1–5] cmH2O and 4 [1–7] cmH2O, respectively).
As compared to standard oxygen, 50 L/min of HFOTTRACHEAL are needed to improve oxygenation, reduce respiratory rate and provide small degree of positive airway expiratory pressure, which, however, is significantly lower than the one produced by HFOTNASAL.

Extracorporeal liver support in patients with liver failure: a systematic review and meta-analysis of randomized trials

Alshamsi, F., Alshammari, K., Belley-Cote, E. et al. Intensive Care Med (2019).

First online: 07.10.2019

Acute liver failure (ALF) and acute on chronic liver failure (ACLF) are associated with significant mortality and morbidity. Extracorporeal liver support (ECLS) devices have been used as a bridge to liver transplant; however, the efficacy and safety of ECLS are unclear. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to examine the efficacy and safety of ECLS in liver failure.
We searched MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials from inception through March 13, 2019. RCTs comparing ECLS to usual care in ALF or ACLF were included. We used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the certainty of the evidence.
We identified 25 RCTs (1796 patients). ECLS use was associated with reduction in mortality (RR 0.84; 95% CI 0.74, 0.96, moderate certainty) and improvement in hepatic encephalopathy (HE) (RR 0.71; 95% CI 0.60, 0.84, low certainty) in patients with ALF or ACLF. The effect of ECLS on hypotension (RR 1.46; 95% CI 0.98, 2.2, low certainty), bleeding (RR 1.21; 95% CI 0.88, 1.66, moderate certainty), thrombocytopenia (RR 1.62; 95% CI 1.0, 2.64, very low certainty) and line infection (RR 1.92; 95% CI 0.11, 33.44, low certainty) was uncertain.

ECLS may reduce mortality and improve HE in patients with ALF and ACLF. The effect on other outcomes is uncertain. However, the evidence is limited by risk of bias and imprecision, and larger trials are needed to better determine the effect of ECLS on patient-important outcomes.

Lactated Ringer’s Versus 4% Albumin on Lactated Ringer’s in Early Sepsis Therapy in Cancer Patients: A Pilot Single-Center Randomized Trial

by Park, Clarice Hyesuk Lee; de Almeida, Juliano Pinheiro; de Oliveira, Gisele Queiroz; Rizk, Stéphanie Itala; Fukushima, Julia Tizue; Nakamura, Rosana Ely; Mourão, Matheus Moraes; Galas, Filomena Regina Barbosa Gomes; Abdala, Edson; Pinheiro Freire, Maristela; Kalil Filho, Roberto; Costa Auler, Jose Otavio Jr; Nardelli, Pasquale; Martin, Greg S.; Landoni, Giovanni; Hajjar, Ludhmila Abrahao

Objective: To investigate the effects of the administration of 4% albumin on lactated Ringer’s, when compared with lactated Ringer’s alone, in the early phase of sepsis in cancer patients.
Design: Single-center, randomized, double-blind, controlled-parallel trial.
Setting: A tertiary care university cancer hospital.
Patients: Cancer patients with severe sepsis or septic shock. Interventions: Between October 2014 and December 2016, patients were randomly assigned to receive either bolus of albumin in a lactated Ringer’s solution or lactated Ringer’s solution alone during the first 6 hours of fluid resuscitation after intensive care medicine (ICU) admission. Primary outcome was defined as death from any cause at 7 days. Secondary outcomes were defined as death from any cause within 28 days, change in Sequence Organ Failure Assessment scores from baseline to day 7, days alive and free of mechanical ventilation, days alive and free of vasopressor, renal replacement therapy during ICU stay, and length of ICU and hospital stay.
Measurements and Main Results: A total of 360 patients were enrolled in the trial. At 7 days, 46 of 180 patients (26%) died in the albumin group and 40 of 180 (22%) died in the lactated Ringer’s group (p = 0.5). At 28 days, 96 of 180 patients (53%) died in the albumin group and 83 of 180 (46%) died in the lactated Ringer’s group (p = 0.2). No significant differences in secondary outcomes were observed.
Conclusions: Adding albumin to early standard resuscitation with lactated Ringer’s in cancer patients with sepsis did not improve 7-day survival.

Early prediction of noninvasive ventilation failure in COPD patients: derivation, internal validation, and external validation of a simple risk score

by Jun Duan, Shengyu Wang, Ping Liu, Xiaoli Han, Yao Tian, Fan Gao, Jing Zhou, Junhuan Mou, Qian Qin, Jingrong Yu, Linfu Bai, Lintong Zhou and Rui Zhang

Annals of Intensive Care volume 9, Article number: 108 (2019)

Early identification of noninvasive ventilation (NIV) failure is a promising strategy for reducing mortality in chronic obstructive pulmonary disease (COPD) patients. However, a risk-scoring system is lacking.
To develop a scale to predict NIV failure, 500 COPD patients were enrolled in a derivation cohort. Heart rate, acidosis (assessed by pH), consciousness (assessed by Glasgow coma score), oxygenation, and respiratory rate (HACOR) were entered into the scoring system. Another two groups of 323 and 395 patients were enrolled to internally and externally validate the scale, respectively. NIV failure was defined as intubation or death during NIV.
Using HACOR score collected at 1–2 h of NIV to predict NIV failure, the area under the receiver operating characteristic curves (AUC) was 0.90, 0.89, and 0.71 for the derivation, internal-validation, and external-validation cohorts, respectively. For the prediction of early NIV failure in these three cohorts, the AUC was 0.91, 0.96, and 0.83, respectively. In all patients with HACOR score > 5, the NIV failure rate was 50.2%. In these patients, early intubation (< 48 h) was associated with decreased hospital mortality (unadjusted odds ratio = 0.15, 95% confidence interval 0.05–0.39, p < 0.01).
HACOR scores exhibited good predictive power for NIV failure in COPD patients, particularly for the prediction of early NIV failure (< 48 h). In high-risk patients, early intubation was associated with decreased hospital mortality.

Randomized Clinical Trial of an ICU Recovery Pilot Program for Survivors of Critical Illness*

Bloom, Sarah L.; Stollings, Joanna L.; Kirkpatrick, Olivia; Wang, Li; Byrne, Daniel W.; Sevin, Carla M.; Semler, Matthew W.

Objectives: To examine the effect of an interdisciplinary ICU recovery program on process measures and clinical outcomes.
Design: A prospective, single-center, randomized pilot trial.
Setting: Academic, tertiary-care medical center.
Patients: Adult patients admitted to the medical ICU for at least 48 hours with a predicted risk of 30-day same-hospital readmission of at least 15%.
Interventions: Patients randomized to the ICU recovery program group were offered a structured 10-intervention program, including an inpatient visit by a nurse practitioner, an informational pamphlet, a 24 hours a day, 7 days a week phone number for the recovery team, and an outpatient ICU recovery clinic visit with a critical care physician, nurse practitioner, pharmacist, psychologist, and case manager. For patients randomized to the usual care group, all aspects of care were determined by treating clinicians.
Measurements and Main Results: Among the primary analysis of enrolled patients who survived to hospital discharge, patients randomized to the ICU recovery program (n = 111) and usual care (n = 121) were similar at baseline. Patients in the ICU recovery program group received a median of two interventions compared with one intervention in the usual care group (p < 0.001). A total of 16 patients (14.4%) in the ICU recovery program group and 26 patients (21.5%) in the usual care group were readmitted to the study hospital within 30 days of discharge (p = 0.16). For these patients, the median time to readmission was 21.5 days (interquartile range, 11.5–26.2 d) in the ICU recovery program group and 7 days (interquartile range, 4–21.2 d) in the usual care group (p = 0.03). Four patients (3.6%) in the ICU recovery program and 14 patients (11.6%) in the usual care group were readmitted within 7 days of hospital discharge (p = 0.02). The composite outcome of death or readmission within 30 days of hospital discharge occurred in 20 patients (18%) in the ICU recovery program group and 36 patients (29.8%) in usual care group (p = 0.04).
Conclusions: This randomized pilot trial found that a multidisciplinary ICU recovery program could deliver more interventions for post ICU recovery than usual care. The finding of longer time-to-readmission with an ICU recovery program should be examined in future trials.

Continuous Renal Replacement Therapy in Pediatric Severe Sepsis: A Propensity Score-Matched Prospective Multicenter Cohort Study in the PICU

by Miao, Huijie; Shi, Jingyi; Wang, Chunxia; Lu, Guoping; Zhu, Xiaodong; Wang, Ying; Cui, Yun; Zhang, Yucai 

Objectives: Continuous renal replacement therapy becomes available utilization for pediatric critically ill, but the impact of mortality rate in severe sepsis remains no consistent conclusion. The aim of the study is to assess the effect of continuous renal replacement therapy in pediatric patients with severe sepsis and the impact this therapy may have on their mortality.
Design: Propensity score-matched cohort study analyzing data prospectively collected by the PICUs over 2 years (2016–2018).
Setting: Four PICUs of tertiary university children’s hospital in China. Patients: The consecutive patients with severe sepsis admitted to study PICUs were enrolled from July 2016 to June 2018. Interventions: The patients were divided into the continuous renal replacement therapy group and the conventional (noncontinuous renal replacement therapy) group.
Measurements and Main Results: A total of 324 patients with severe sepsis were enrolled. The hospital mortality rate was 35.6% (64/180) in the continuous renal replacement therapy group and 47.9% (69/144) in the noncontinuous renal replacement therapy group. After propensity score adjustment, the hospital mortality rate was 21.3% (29/136) in the continuous renal replacement therapy group and 32.4% (44/136) in the noncontinuous renal replacement therapy group. In subgroup analysis, the relative risk of dying was 0.447 (95% CI, 0.208–0.961) only in patients complicated by acute respiratory distress syndrome (p = 0.037), but not in patients with shock, acute kidney injury, acute liver dysfunction, encephalopathy, and fluid overload greater than 10%. The mean duration of continuous renal replacement therapy was 45 hours (26–83 hr) with an ultrafiltration rate of 50 mL/kg/hr. The level of interleukin-6 was decreased, and the percent of natural killer cells (%) was improved in the continuous renal replacement therapy group compared with the noncontinuous renal replacement therapy group. Furthermore, continuous renal replacement therapy was an independently significant risk factor for hospital mortality in pediatric patients with severe sepsis, and the interval between continuous renal replacement therapy initiation and PICU admission was an independent risk factor for hospital mortality in patients receiving continuous renal replacement therapy.
Conclusions: Continuous renal replacement therapy with an ultrafiltration rate of 50 mL/kg/hr decreases hospital mortality rate in pediatric severe sepsis, especially in patients with acute respiratory distress syndrome.

A Core Outcome Set for Critical Care Ventilation Trials

by Blackwood, Bronagh; Ringrow, Suzanne; Clarke, Mike; Marshall, John C.; Connolly, Bronwen; Rose, Louise; McAuley, Daniel F

Objectives: Our objective was to obtain international consensus on a set of core outcome measures that should be recorded in all clinical trials of interventions intended to modify the duration of ventilation for invasively mechanically ventilated patients in the ICU.
Design: A two-stage consensus process was undertaken between December 2015 and January 2018. Stage 1 included an online three-round Delphi study and three consensus meetings. Stage 2 included three consensus meetings.
Setting: The setting was international, including Europe, North and South America, Australia, Asia, and Africa.
Participants: Organization members representing intensive care survivors and carers; nursing, allied health professionals, and critical care physicians; clinical trials groups and trial investigators; and industry.
Interventions: None.
Measurements and Main Results: Delphi study outcomes were scored by participants from one (least important) to nine (most important). Consensus criteria for including the outcome in the core set were more than 70% of responses rating the outcome above seven and not more than 15% rating the outcome less than 3. From 222 participants, 183 from 38 organizations in 27 countries contributed to the consensus process. Stage 1: Delphi response rates from 200 participants ranged from 89% to 90% across three rounds. Forty-seven outcomes were ranked as follows: 19 met consensus criteria for inclusion and were considered at three consensus meetings (33 participants). Six outcomes were agreed for the core set as follows: extubation, reintubation, duration of mechanical ventilation, length of stay, health-related quality of life, and mortality. Stage 2: Three consensus meetings (37 participants) agreed on the measures for each outcome.
Conclusions: We used rigorous and well-established methods to develop a core outcome set for use in all clinical trials evaluating interventions intended to modify duration of mechanical ventilation. This core outcome set will inform the design of future trials in this field by strengthening methodological quality and improving comparability across trials.