From ICU Syndromes to ICU Subphenotypes: Consensus Report and Recommendations For Developing Precision Medicine in ICU.

Critical care uses syndromic definitions to describe patient groups for clinical practice and research. There is growing recognition that a "precision medicine" approach is required and that integrated biologic and physiologic data identify reproducible subpopulations that may respond differently to treatment. This article reviews the current state of the field and considers how to successfully transition to a precision medicine approach. In order to impact clinical care, identified subpopulations must do more than differentiate prognosis. They must differentiate response to treatment, ideally by defining subgroups with distinct functional or pathobiological mechanisms (endotypes). There are now multiple examples of reproducible subpopulations of sepsis, acute respiratory distress syndrome, and acute kidney or brain injury described using clinical, physiological, and/or biological data. Many of these subpopulations have demonstrated the potential to define differential treatment response, largely in retrospective studies, and that the same treatment-responsive subpopulations may cross multiple clinical syndromes (treatable traits). To bring about a change in clinical practice, a precision medicine approach must be evaluated in prospective clinical studies requiring novel adaptive trial designs. Several such studies are underway but there are multiple challenges to be tackled. Such subpopulations must be readily identifiable and be applicable to all critically ill populations around the world. Subdividing clinical syndromes into subpopulations will require large patient numbers. Global collaboration of investigators, clinicians, industry and patients over many years will therefore be required to transition to a precision medicine approach and ultimately realize treatment advances seen in other medical fields. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Estimated glomerular filtration rate among intensive care unit survivors: From the removal of race coefficient to cystatin C-based equations.

PURPOSE: Black race coefficient used in serum creatinine (sCr)-based estimated glomerular filtration rate (eGFR) calculation may perpetuate racial disparities. Among intensive care unit (ICU) survivors, sCr overestimates kidney function due to sarcopenia. Cystatin C (cysC) is a race- and muscle mass-independent eGFR marker. We investigated the impact of removing the race coefficient from sCr-based eGFR and compared cysC- and sCr-based eGFR in ICU survivors. MATERIALS AND METHODS: Among 30,920 patients from 2 institutions in the Bronx and Boston, eGFR was calculated at hospital discharge using sCr-based equations with and without race coefficient (eGFRsCr2009 and eGFRsCr2021). In a subset with available cysC between ICU admission and 1-year follow-up, sCr- and cysC-based estimates were compared. RESULTS: eGFRsCr2021 was higher than eGFRsCr2009 by a median of 4 ml/min/1.73 m2 among non-Black patients and lower by a median of 8 ml/min/1.73 m2 among Black patients. Removing race coefficient reclassified 12.9% of non-Black subjects and 16.1% of Black subjects to better and worse eGFR category, respectively, and differentially impacted the prevalence of kidney dysfunction between the institutions due to differences in racial composition. Among 51 patients with available cysC (108 measurements), cysC-based estimates were lower than sCr-based estimates (median difference 9 to 16 ml/min/1.73 m2), resulting in reclassification to worse eGFR category in 34% to 53.5% of measurements. CONCLUSIONS: Among ICU survivors, removal of race coefficient leads to lower eGFR in Black patients and may contribute to overestimation of kidney function in non-Black patients. While cysC is rarely used, estimates based on this marker are significantly lower than those based on sCr.

Design and implementation of the hospital airway resuscitation trial.

Guidelines for the management of in-hospital cardiac arrest resuscitation are often drawn from evidence generated in out-of-hospital cardiac arrest populations and applied to the in-hospital setting. Approach to airway management during resuscitation is one example of this phenomenon, with the recommendation to place either a supraglottic airway or endotracheal tube when performing advanced airway management during in-hospital cardiac arrest based mainly in clinical trials conducted in the out-of-hospital setting. The Hospital Airway Resuscitation Trial (HART) is a pragmatic cluster-randomized superiority trial comparing a strategy of first choice supraglottic airway to a strategy of first choice endotracheal intubation during resuscitation from in-hospital cardiac arrest. The design includes a number of innovative elements such as a highly pragmatic design drawing from electronic health records and a novel primary outcome measure for cardiac arrest trials-alive-and-ventilator free days. Many of the topics explored in the design of HART have wide relevance to other trials in in-hospital cardiac arrest populations.

"Postponing it Any Later Would not be so Great": A Cognitive Interview Study of How Physicians Decide to Initiate Goals of Care Discussions in the Hospital.

BACKGROUND: There are missed opportunities to discuss goals and preferences for care with seriously ill patients in the acute care setting. It is unknown which factors most influence clinician decision-making about communication at the point of care. OBJECTIVE: This study utilized a cognitive-interviewing technique to better understand what leads clinicians to decide to have a goals of care (GOC) discussion in the acute care setting. METHODS: A convenience sample of 15 oncologists, intensivists and hospitalists were recruited from a single academic medical center in a large urban area. Participants completed a cognitive interview describing their thought process when deciding whether to engage in GOC discussions in clinical vignettes. RESULTS: 6 interconnected factors emerged as important in determining how likely the physician was to consider engaging in GOC at that time; (1) the participants' mental model of GOC, (2) timing of GOC related to stability, acuity and reversibility of the patient's condition, (3) clinical factors such as uncertainty, prognosis and recency of diagnosis, (4) patient factors including age and emotional state, (5) participants' role on the care team, and (6) clinician factors such as emotion and communication skill level. CONCLUSION: Participants were hesitant to commit to the present moment as the right time for GOC discussions based on variations in clinical presentation. Clinical decision support systems that include more targeted information about risk of clinical deterioration and likelihood of reversal of the acute condition may prompt physicians to discuss GOC, but more support for managing discomfort with uncertainty is also needed.

Long short-term memory model identifies ARDS and in-hospital mortality in both non-COVID-19 and COVID-19 cohort.

OBJECTIVE: To identify the risk of acute respiratory distress syndrome (ARDS) and in-hospital mortality using long short-term memory (LSTM) framework in a mechanically ventilated (MV) non-COVID-19 cohort and a COVID-19 cohort. METHODS: We included MV ICU patients between 2017 and 2018 and reviewed patient records for ARDS and death. Using active learning, we enriched this cohort with MV patients from 2016 to 2019 (MV non-COVID-19, n=3905). We collected a second validation cohort of hospitalised patients with COVID-19 in 2020 (COVID+, n=5672). We trained an LSTM model using 132 structured features on the MV non-COVID-19 training cohort and validated on the MV non-COVID-19 validation and COVID-19 cohorts. RESULTS: Applying LSTM (model score 0.9) on the MV non-COVID-19 validation cohort had a sensitivity of 86% and specificity of 57%. The model identified the risk of ARDS 10 hours before ARDS and 9.4 days before death. The sensitivity (70%) and specificity (84%) of the model on the COVID-19 cohort are lower than MV non-COVID-19 cohort. For the COVID-19 + cohort and MV COVID-19 + patients, the model identified the risk of in-hospital mortality 2.4 days and 1.54 days before death, respectively. DISCUSSION: Our LSTM algorithm accurately and timely identified the risk of ARDS or death in MV non-COVID-19 and COVID+ patients. By alerting the risk of ARDS or death, we can improve the implementation of evidence-based ARDS management and facilitate goals-of-care discussions in high-risk patients. CONCLUSION: Using the LSTM algorithm in hospitalised patients identifies the risk of ARDS or death.

Thiamine for Renal Protection in Septic Shock (TRPSS): A Randomized, Placebo-controlled, Clinical Trial.

Rationale: Kidney injury is common and associated with worse outcomes in patients with septic shock. Mitochondrial resuscitation with thiamine (vitamin B1) may attenuate septic kidney injury. Objectives: To assess whether thiamine supplementation attenuates kidney injury in septic shock. Methods: The TRPSS (Thiamine for Renal Protection in Septic Shock) trial was a multicenter, randomized, placebo-controlled trial of thiamine versus placebo in septic shock. The primary outcome was change in serum creatinine between enrollment and 72 hours after enrollment. Measurements and Main Results: Eighty-eight patients were enrolled (42 patients received the intervention, and 46 received placebo). There was no significant between-groups difference in creatinine at 72 hours (mean difference, -0.57 mg/dl; 95% confidence interval, -1.18, 0.04; P = 0.07). There was no difference in receipt of kidney replacement therapy (14.3% vs. 21.7%, P = 0.34), acute kidney injury (as defined by stage 3 of the Kidney Disease: Improving Global Outcomes acute kidney injury scale; 54.7% vs. 73.9%, P = 0.07), or mortality (35.7% vs. 54.3%, P = 0.14) between the thiamine and placebo groups. Patients who received thiamine had more ICU-free days (median [interquartile range]: 22.5 [0.0-25.0] vs. 0.0 [0.0-23.0], P < 0.01). In the thiamine-deficient cohort (27.4% of patients), there was no difference in rates of kidney failure (57.1% thiamine vs. 81.5% placebo) or in-hospital mortality (28.6% vs. 68.8%) between groups. Conclusions: In the TRPSS trial, there was no statistically significant difference in the primary outcome of change in creatinine over time. Patients who received thiamine had more ICU-free days, but there was no difference in other secondary outcomes. Clinical trial registered with www.clinicaltrials.gov (NCT03550794).

Resuscitation in the First 3 Hours of Sepsis-Induced Hypotension Varies by Patient and Hospital Factors.

Patient and hospital factors affects how we resuscitate patients in the first 3 hours of sepsis-induced hypotension. OBJECTIVES: To evaluate variability in compliance to the 3-hour surviving sepsis campaign (SSC) bundle and explore the association of early compliance with subsequent shock and in-hospital mortality. DESIGN: Retrospective cohort study between September 2017 and February 2018. SETTING: Thirty-four academic medical centers. PARTICIPANTS: A subgroup sepsis-induced hypotensive patients from a larger shock cohort study. MAIN OUTCOMES AND MEASURES: Compliance to SSC bundle that was defined as receiving appropriate antibiotics, 30 mL/kg of crystalloid or initiation of vasopressors, and lactate, obtained in the first 3 hours following sepsis-induced hypotension. RESULTS: We included 977 patients with septic-induced hypotension. Bundle compliance was 43.8%, with the lowest compliance to fluid or vasopressor components (56%). Patients with high Sequential Organ Failure Assessment scores and physiologic assessments were more likely to receive compliant care, as were patients with sepsis-induced hypotension onset in the emergency department (ED) or admitted to mixed medical-surgical ICUs. SSC compliance was not associated with in-hospital mortality (adjusted odds ratio, 0.72; 95% CI, 0.47-1.10). The site-to-site variability contributed to SSC compliance (intraclass correlation coefficient [ICC], 0.15; 95% CI, 0.07-0.3) but not in-hospital mortality (ICC, 0.02; 95% CI, 0.001-0.24). Most patients remained in shock after 3 hours of resuscitation (SSC compliant 81.1% and noncompliant 53.7%). Mortality was higher among patients who were persistently hypotensive after 3 hours of resuscitation for both the SSC compliant (persistent hypotension 37% vs not hypotensive 27.2%; p = 0.094) and noncompliant (30.1% vs 18.2%; p = 0.001, respectively). CONCLUSIONS AND RELEVANCE: Patients with a higher severity of illness and sepsis-induced hypotension identified in the ED were more likely to receive SSC-compliant care. SSC compliance was not associated with in-hospital mortality after adjusting for patient- and hospital-level differences. Higher mortality is seen among those who remain in shock after initial resuscitation, regardless of SSC compliance.

Assessing a standardized decision-making algorithm for blood culture collection in the intensive care unit.

PURPOSE: Blood cultures are commonly ordered for patients with low risk of bacteremia. Indications for obtaining blood cultures are often broad and ill defined, and decision algorithms for appropriate blood cultures have not been comprehensively evaluated in critically-ill populations. METHODS: We conducted a retrospective analysis to assess the frequency of inappropriate blood cultures in the ICUs at Montefiore Medical Center based on an evidence-based guidance algorithm. Blood cultures were reviewed against this algorithm to determine their appropriateness. We calculated the prevalence of inappropriate blood culture and explored the reasons for these collected cultures. RESULTS: 300 patients were randomly selected from an initial cohort of 3370 patients. 294 patients were included and of these, 167 patients had at least 1 blood culture drawn. 125 patients had one or more inappropriate blood culture. 61.4% of blood cultures drawn were assessed to be inappropriate. The most common reason for inappropriate cultures was a culture drawn as a result of isolated fever or leukocytosis. CONCLUSION: In a cohort of critically-ill patients, inappropriate blood cultures were common. The indications for blood cultures are often not evidence-based, and evidence-based algorithms to guide the collection of blood cultures may offer a way to decrease inappropriate culture orders.

Triglyceride Concentrations and Their Relationship to Sedation Choice and Outcomes in Mechanically Ventilated Patients Receiving Propofol.

Rationale: Propofol is a first-line sedative agent in the intensive care unit (ICU) but may be associated with hypertriglyceridemia and pancreatitis. To date, the relationship between propofol-induced hypertriglyceridemia and pancreatitis, as well as clinician responses to propofol-induced hypertriglyceridemia, have not been comprehensively studied. Objectives: To assess the incidence of hypertriglyceridemia and pancreatitis in patients receiving continuous propofol infusions in the ICU and to describe the association between hypertriglyceridemia and the use of nonpropofol continuous sedative infusions. Methods: This was a retrospective observational cohort study conducted at three urban academic hospitals within a single health system. Findings were additionally validated using the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database containing data from a separate tertiary care hospital. Mechanically ventilated adult patients who received a continuous propofol infusion between 2016 and 2021 were included. The primary exposure was serum triglyceride concentration, and hypertriglyceridemia was defined as a triglyceride concentration greater than 400 mg/dl. Outcomes included new-onset pancreatitis as well as receipt of midazolam, dexmedetomidine, or ketamine after the triglyceride measurement. The incidence of pancreatitis was compared between groups using a Fisher's Exact test. Multivariable logistic regression was used to assess the association between dichotomized triglyceride concentration and alternative sedative use. Results: In the primary cohort of 7,037 patients, 1,724 (24.5%) had one or more triglyceride concentration measured. Of these, 1,365 (79.2%) had a maximum concentration of less than 400 mg/dl, and 359 (20.8%) had a maximum concentration of greater than 400 mg/dl. Compared with patients with low triglyceride concentrations, patients with high triglyceride concentrations were more likely to receive a continuous infusion of midazolam (37.0% vs. 16.4%; adjusted odds ratio [aOR], 3.1; 95% confidence interval [CI], 2.2-4.4; P < 0.01), ketamine (22.8% vs. 6.9%; aOR, 3.5; 95% CI, 2.3-5.3; P < 0.01), and dexmedetomidine (57.7% vs. 46.6%; aOR, 1.5; 95% CI, 1.1-2.0; P < 0.01). Rates of midazolam infusion increased as triglyceride concentrations exceeded 500 mg/dl. Forty-four (0.6%) patients developed pancreatitis after propofol initiation, of which 4 (9.1%) were considered related to propofol-associated hypertriglyceridemia. Findings were similar in the MIMIC-IV cohort. Conclusions: Propofol-associated hypertriglyceridemia is relatively common in mechanically ventilated ICU patients who have triglycerides measured. Pancreatitis related to propofol-associated hypertriglyceridemia is rare. Patients who develop hypertriglyceridemia while receiving propofol are more likely to receive continuous infusions of other sedatives.

Utility of Screening for Cognitive Impairment at Hospital Discharge in Adult Survivors of Critical Illness.

BACKGROUND: Few studies have explored the utility of screening for cognitive impairment near hospital discharge in intensive care unit survivors. OBJECTIVES: To explore baseline and hospitalization characteristics associated with cognitive impairment at hospital discharge and the relationship between cognitive impairment and 6-month disability and mortality outcomes. METHODS: Hospital disability status and treatment variables were collected from 2 observational cohort studies. Patients were screened for cognitive impairment at hospital discharge using the Montreal Cognitive Assessment (MoCA)-Blind, and telephone follow-up was conducted 6 months after discharge to assess vital and physical disability status. RESULTS: Of 423 patients enrolled, 320 were alive at hospital discharge. A total of 213 patients (66.6%) were able to complete the MoCA near discharge; 47 patients (14.7%) could not complete it owing to cognitive impairment. In MoCA completers, the median (IQR) score was 17 (14-19). Older age (ß per year increase, -0.09 [95% CI, -0.13 to -0.05]) and blood transfusions during hospitalization (ß, -1.20 [95% CI, -2.26 to -0.14]) were associated with lower MoCA scores. At 6-month follow-up, 176 of 213 patients (82.6%) were alive, of whom 41 (23.3%) had new severe physical disabilities. Discharge MoCA score was not significantly associated with 6-month mortality (adjusted odds ratio, 1.03 [95% CI, 0.93-1.14]) but was significantly associated with risk of new severe disability at 6 months (adjusted odds ratio, 0.85 [95% CI, 0.76-0.94]). CONCLUSION: Assessing for cognitive impairment at hospital discharge may help identify intensive care unit survivors at higher risk of severe physical disabilities after critical illness.

Epidemiology of Organ Failure Before and During COVID-19 Pandemic Surge Conditions.

BACKGROUND: Understanding the distribution of organ failure before and during the COVID-19 pandemic surge can provide a deeper understanding of how the pandemic strained health care systems and affected outcomes. OBJECTIVE: To assess the distribution of organ failure in 3 New York City hospitals during the COVID-19 pandemic. METHODS: A retrospective cohort study of adult admissions across hospitals from February 1, 2020, through May 31, 2020, was conducted. The cohort was stratified into those admitted before March 17, 2020 (prepandemic) and those admitted on or after that date (SARS-CoV-2-positive and non-SARS-CoV-2). Sequential Organ Failure Assessment scores were computed every 2 hours for each admission. RESULTS: A total of 1 794 975 scores were computed for 20 704 admissions. Before and during the pandemic, renal failure was the most common type of organ failure at admission and respiratory failure was the most common type of hospital-onset organ failure. The SARS-CoV-2-positive group showed a 231% increase in respiratory failure compared with the prepandemic group. More than 65% of hospital-onset organ failure in the prepandemic group and 83% of hospital-onset respiratory failure in the SARS-CoV-2-positive group occurred outside intensive care units. The SARS-CoV-2-positive group showed a 341% increase in multiorgan failure compared with the prepandemic group. Compared with the prepandemic and non-SARS-CoV-2 patients, SARS-CoV-2-positive patients had significantly higher mortality for the same admission and maximum organ failure score. CONCLUSION: Most hospital-onset organ failure began outside intensive care units, with a marked increase in multiorgan failure during pandemic surge conditions and greater hospital mortality for the severity of organ failure.

Quantifying Utilitarian Outcomes to Inform Triage Ethics: Simulated Performance of a Ventilator Triage Protocol under Sars-CoV-2 Pandemic Surge Conditions.

BACKGROUND: Equitable protocols to triage life-saving resources must be specified prior to shortages in order to promote transparency, trust and consistency. How well proposed utilitarian protocols perform to maximize lives saved is unknown. We aimed to estimate the survival rates that would be associated with implementation of the New York State 2015 guidelines for ventilator triage, and to compare them to a first-come-first-served triage method. METHODS: We constructed a simulation model based on a modified version of the New York State 2015 guidelines compared to a first-come-first-served method under various hypothetical ventilator shortages. We included patients with SARs-CoV-2 infection admitted with respiratory failure requiring mechanical ventilation to three acute care hospitals in New York from 3/01/2020 and 5/27/2020. We estimated (1) survival rates, (2) number of excess deaths, (3) number of patients extubated early or not allocated a ventilator due to capacity constraints, (4) survival rates among patients not allocated a ventilator at triage or extubated early due to capacity constraints. RESULTS: 807 patients were included in the study. The simulation model based on a modified New York State policy did not decrease mortality, excess death or exclusion from ventilators compared to the first-come-first-served policy at every ventilator capacity we tested using COVID-19 surge cohort patients. Survival rates were similar at all the survival probabilities estimated. At the lowest ventilator capacity, the modified New York State policy has an estimated survival of 28.5% (CI: 28.4-28.6), compared to 28.1% (CI: 27.7-28.5) for the first-come-first-served policy. CONCLUSIONS: This simulation of a modified New York State guideline-based triage protocol revealed limitations in achieving the utilitarian goals these protocols are designed to fulfill. Quantifying these outcomes can inform a better balance among competing moral aims.

The Future of Critical Care: Optimizing Technologies and a Learning Healthcare System to Potentiate a More Humanistic Approach to Critical Care.

While technological innovations are the invariable crux of speculation about the future of critical care, they cannot replace the clinician at the bedside. This article summarizes the work of the Society of Critical Care Medicine-appointed multiprofessional task for the Future of Critical Care. The Task Force notes that critical care practice will be transformed by novel technologies, integration of artificial intelligence decision support algorithms, and advances in seamless data operationalization across diverse healthcare systems and geographic regions and within federated datasets. Yet, new technologies will be relevant and meaningful only if they improve the very human endeavor of caring for someone who is critically ill.

Modeling Outcomes Using Sequential Organ Failure Assessment (SOFA) Score-Based Ventilator Triage Guidelines During the COVID-19 Pandemic.

OBJECTIVE: To model performance of the Sequential Organ Failure Assessment (SOFA) score-based ventilator allocation guidelines during the COVID-19 pandemic. METHODS: A retrospective cohort study design was used. Study sites included 3 New York City hospitals in a single academic medical center. We included a random sample (205) of adult patients who were intubated (1002) from March 25, 2020, till April 29, 2020. Protocol criteria adapted from the New York State's 2015 guidelines were applied to determine which patients would have had mechanical ventilation withheld or withdrawn. RESULTS: 117 (57%) patients would have been identified for ventilator withdrawal or withholding based on the triage guidelines. Of those 117 patients, 28 (24%) survived hospitalization. Overall, 65 (32%) patients survived to discharge. CONCLUSION: Triage protocols aim to maximize survival by redirecting ventilators to those most likely to survive. Over 50% of this sample would have been identified as candidates for ventilator exclusion. Clinical judgment would therefore still be needed in ventilator reallocation, thus re-introducing bias and moral distress. This data suggests limited utility for SOFA score-based ventilator rationing. It raises the question of whether there is sufficient ethical justification to impose a life-ending decision based on a SOFA scoring method on some patients in order to offer potential benefit to a modest number of others.

Impact of ABCDE Bundle Implementation in the Intensive Care Unit on Specific Patient Costs.

OBJECTIVES: To measure the impact of full versus partial ABCDE bundle implementation on specific cost centers and related resource utilization. DESIGN: Retrospective cohort study. SETTING: Two medical ICUs within Montefiore Health System (Bronx, NY). PATIENTS: Four hundred and seventy-two mechanically ventilated patients admitted to the medical ICUs during a hospitalization which began and ended between January 1, 2013 and December 31, 2013. INTERVENTIONS: The full (A)wakening, (B)reathing, (C)oordination, (D)elirium Monitoring/Management and (E)arly Mobilization bundle was implemented in the intervention ICU while a portion of the bundle (A, B, and D components) was implemented in the comparison ICU. MEASUREMENTS AND MAIN RESULTS: Relative to the comparison ICU, implementation of the entire bundle in the intervention ICU was associated with a 27.3% (95% CI: 9.9%, 41.3%; P = 0.004) decrease in total hospital laboratory costs and a 2,888.6% (95% CI: 77.9%, 50,113.2%; P = 0.018) increase in total hospital physical therapy costs. Cost of total hospital medications, diagnostic radiology and respiratory therapy were unchanged. Relative to the comparison ICU, total hospital resource use decreased in the intervention ICU (incidence rate ratio [95% CI], laboratory: 0.68 [0.54, 0.87], P = 0.002; diagnostic radiology: 0.75 [0.59, 0.96], P = 0.020). CONCLUSIONS: Full ABCDE bundle implementation resulted in a decrease in total hospital laboratory costs and total hospital laboratory and diagnostic resource utilization while leading to an increase in physical therapy costs.

Current practice and evolving concepts in septic shock resuscitation.

Clinical and pathophysiological understanding of septic shock has progressed exponentially in the previous decades, translating into a steady decrease in septic shock-related morbidity and mortality. Even though large randomized, controlled trials have addressed fundamental aspects of septic shock resuscitation, many questions still exist. In this review, we will describe the current standards of septic shock resuscitation, but the emphasis will be placed on evolving concepts in different domains such as clinical resuscitation targets, adequate use of fluids and vasoactive drugs, refractory shock, and the use of extracorporeal therapies. Multiple research opportunities remain open, and collaborative endeavors should be performed to fill in these gaps.

The Impact of High-Flow Nasal Cannula Use on Patient Mortality and the Availability of Mechanical Ventilators in COVID-19.

Rationale: How to provide advanced respiratory support for coronavirus disease (COVID-19) to maximize population-level survival while optimizing mechanical ventilator access is unknown.Objectives: To evaluate the use of high-flow nasal cannula for COVID-19 on population-level mortality and ventilator availability.Methods: We constructed dynamical (deterministic) simulation models of high-flow nasal cannula and mechanical ventilation use for COVID-19 in the United States. Model parameters were estimated through consensus based on published literature, local data, and experience. We had the following two outcomes: 1) cumulative number of deaths and 2) days without any available ventilators. We assessed the impact of various policies for the use of high-flow nasal cannula (with or without "early intubation") versus a scenario in which high-flow nasal cannula was unavailable.Results: The policy associated with the fewest deaths and the least time without available ventilators combined the use of high-flow nasal cannula for patients not urgently needing ventilators with the use of early mechanical ventilation for these patients when at least 10% of ventilator supply was not in use. At the national level, this strategy resulted in 10,000-40,000 fewer deaths than if high-flow nasal cannula were not available. In addition, with moderate national ventilator capacity (30,000-45,000 ventilators), this strategy led to up to 25 (11.8%) fewer days without available ventilators. For a 250-bed hospital with 100 mechanical ventilators, the availability of 13, 20, or 33 high-flow nasal cannulas prevented 81, 102, and 130 deaths, respectively.Conclusions: The use of high-flow nasal cannula coupled with early mechanical ventilation when supply is sufficient results in fewer deaths and greater ventilator availability.

Prehospital Frailty and Screening Criteria for Palliative Care Services in Critically Ill Older Adults: An Observational Cohort Study.

Background: The use of formalized criteria (or triggers) for palliative care services (PCSs) has been associated with increased use of PCSs in the intensive care unit (ICU). Objective: To explore the utility/validity of frailty as a trigger for providing PCSs. Design: This is a prospective cohort study. Setting/Subjects: Older adults (age ≥50 years) admitted to ICUs were enrolled. Measurements: We measured frailty using the Clinical Frailty Scale. We reviewed electronic health records for the presence/absence of six evidence-based triggers, the use and quality of specialty palliative care (SPC), and markers of primary palliative care (PPC). We used descriptive statistics to describe the differences in PPC, SPC, and six-month mortality by frailty and by the presence/absence of triggers. Results: In a study population of 302 older adults, mean (standard deviation) age 67.2 years (10.5), 151 (50%) were frail and 105 (34.8%) had ≥1 trigger for PCSs. Of the 151 (55.6%) frail patients, 84 had no triggers for PCSs, despite a 46.4% six-month mortality in this group. Patients with ≥1 trigger had higher rates of SPC than those without (39.1% vs. 18.3%, p < 0.001); frail patients also had higher SPC than nonfrail patients (32.5% vs. 18.5%, p = 0.006). Patients with ≥1 trigger had higher rates of PPC than those without (66.7% vs. 44.2%, p < 0.001); no statistically significant difference in PPC was found by frailty (56.3% vs. 47.7%, p = 0.134). Conclusion: The rates of PCSs and six-month mortality by frailty are consistent with frailty being a valid trigger for PCSs in ICUs; the high prevalence of frailty relative to triggers suggests that ways to increase PCSs would be needed.