Outcomes With Single-Site Dual-Lumen Versus Multisite Cannulation for Adults With COVID-19 Respiratory Failure Receiving Venovenous Extracorporeal Membrane Oxygenation

OBJECTIVES

To determine whether multisite versus single-site dual-lumen (SSDL) cannulation is associated with outcomes for COVID-19 patients requiring venovenous extracorporeal membrane oxygenation (VV-ECMO).

DESIGN

Retrospective analysis of the Extracorporeal Life Support Organization Registry. Propensity score matching (2:1 multisite vs SSDL) was used to control for confounders.

PATIENTS

The matched cohort included 2,628 patients (1,752 multisite, 876 SSDL) from 170 centers. The mean ( sd ) age in the entire cohort was 48 (11) years, and 3,909 (71%) were male. Patients were supported with mechanical ventilation for a median (interquartile range) of 79 (113) hours before VV-ECMO support.

INTERVENTIONS

None.

MEASUREMENTS

The primary outcome was 90-day survival. Secondary outcomes included survival to hospital discharge, duration of ECMO support, days free of ECMO support at 90 days, and complication rates.

MAIN RESULTS

There was no difference in 90-day survival (49.4 vs 48.9%, p = 0.66), survival to hospital discharge (49.8 vs 48.2%, p = 0.44), duration of ECMO support (17.9 vs 17.1 d, p = 0.82), or hospital length of stay after cannulation (28 vs 27.4 d, p = 0.37) between multisite and SSDL groups. More SSDL patients were extubated within 24 hours (4% vs 1.9%, p = 0.001). Multisite patients had higher ECMO flows at 24 hours (4.5 vs 4.1 L/min, p < 0.001) and more ECMO-free days at 90 days (3.1 vs 2.0 d, p = 0.02). SSDL patients had higher rates of pneumothorax (13.9% vs 11%, p = 0.03). Cannula site bleeding (6.4% vs 4.7%, p = 0.03), oxygenator failure (16.7 vs 13.4%, p = 0.03), and circuit clots (5.5% vs 3.4%, p = 0.02) were more frequent in multisite patients.

CONCLUSIONS

In this retrospective study of COVID-19 patients requiring VV-ECMO, 90-day survival did not differ between patients treated with a multisite versus SSDL cannulation strategy and there were only modest differences in major complication rates. These findings do not support the superiority of either cannulation strategy in this setting.

Propofol-Based Anesthesia Maintenance and/or Volatile Anesthetics during Intracranial Aneurysm Repair: A Comparative Analysis of Neurological Outcomes

BACKGROUND

Volatile and intravenous anesthetics have substantial effects on physiological functions, notably influencing neurological function and susceptibility to injury. Despite the importance of the anesthetic approach, data on its relative risks or benefits during surgical clipping or endovascular treatments for unruptured intracranial aneurysms (UIAs) remains scant. We investigated whether using volatile anesthetics alone or in combination with propofol infusion yields superior neurological outcomes following UIA obliteration.

METHODS

We retrospectively reviewed 1001 patients who underwent open or endovascular treatment for UIA, of whom 596 had short- and long-term neurological outcome data (modified Rankin Scale) recorded. Multivariable ordinal regression analysis was performed to examine the association between the anesthetic approach and outcomes.

RESULTS

Of 1001 patients, 765 received volatile anesthetics alone, while 236 received propofol infusion and volatile anesthetics (combined anesthetic group). Short-term neurological outcome data were available for 619 patients and long-term data for 596. No significant correlation was found between the anesthetic approach and neurologic outcomes, irrespective of the type of procedure (open craniotomy or endovascular treatment). The combined anesthetic group had a higher rate of ICU admission (p < 0.001) and longer ICU and hospital length of stay (LOS, p < 0.001). Similarly, a subgroup analysis revealed longer ICU and hospital LOS (p < 0.0001 and p < 0.001, respectively) in patients who underwent endovascular UIA obliteration under a combined anesthetic approach (n = 678).

CONCLUSIONS

The addition of propofol to volatile anesthetics during UIA obliteration does not provide short- or long-term benefits to neurologic outcomes. Compared to volatile anesthetics alone, the combination of propofol and volatile anesthetics may be associated with an increased rate of ICU admission, as well as longer ICU and hospital LOS.

Association of neurocognitive disorders with morbidity and mortality in older adults undergoing major surgery in the USA: a retrospective, population-based, cohort study

BACKGROUND

Neurocognitive disorders become increasingly common as patients age, and increasing numbers of surgical interventions are done on older patients. The aim of this study was to understand the clinical characteristics and outcomes of surgical patients with neurocognitive disorders in the USA in order to guide future targeted interventions for better care.

METHODS

This retrospective cohort study used claims data for US Medicare beneficiaries aged 65 years and older with a record of inpatient admission for a major diagnostic or therapeutic surgical procedure between Jan 1, 2017, and Dec 31, 2018. Data were retrieved through a data use agreement between Dartmouth Hitchcock Medical Center and US Centers for Medicare and Medicaid Services via the Research Data Assistance Center. The exposure of interest was the presence of a pre-existing neurocognitive disorder as defined by diagnostic code within 3 years of index hospital admission. The primary outcome was mortality at 30 days, 90 days, and 365 days from date of surgery among all patients with available data.

FINDINGS

Among 5 263 264 Medicare patients who underwent a major surgical procedure, 767 830 (14·59%) had a pre-existing neurocognitive disorder and 4 495 434 (85·41%) had no pre-existing neurocognitive disorder. Adjusting for demographic factors and comorbidities, patients with a neurocognitive disorder had higher 30-day (hazard ratio 1·24 [95% CI 1·23-1·25]; p<0·0001), 90-day (1·25 [1·24-1·26]; p<0·0001), and 365-day mortality (1·25 [1·25-1·26]; p<0·0001) compared with patients without a neurocognitive disorder.

INTERPRETATION

Our findings suggest that the presence of a neurocognitive disorder is independently associated with an increased risk of mortality. Identification of a neurocognitive disorder before surgery can help clinicians to better disclose risks and plan for patient care after hospital discharge.

FUNDING

Department of Anesthesiology and Perioperative Medicine at Dartmouth Hitchcock Medical Center.

Determinants of Professional Fulfillment and Burnout Among Intensivists: A National Survey by the Society of Critical Care Anesthesiologists in 2022

BACKGROUND

Increased burnout and decreased professional fulfillment among intensive care physicians is partly due to intensive care unit (ICU) workload. Although the SARS-CoV-2 (COVID-19) pandemic increased ICU workload, it also may have increased feelings of personal fulfillment due to positive public perceptions of physicians caring for COVID patients. We surveyed critical care anesthesiologists to identify the effect of provider demographics, ICU workload, and COVID-19-related workload, on professional fulfillment and burnout.

METHODS

We performed an exploratory survey of 606 members of the Society of Critical Care Anesthesiologists (SOCCA) in January and February 2022. We used the Stanford Professional Fulfillment Index (PFI) to grade levels of professional fulfillment and markers of burnout (ie, work exhaustion and disengagement). Univariable and multivariable models were used to identify associations between provider demographics and practice characteristics and professional fulfillment and work exhaustion.

RESULTS

One hundred and seventy-five intensivists (29%) responded. A total of 65% were male and 49% were between 36 and 45 years old. The overall median PFI score-0 (none) to 24 (most professional fulfillment)-was 17 (IQR, 1-24), with a wide distribution of responses. In multivariable analysis, factors associated with higher professional fulfillment included age >45 years ( P =.004), ≤15 weeks full-time ICU coverage in 2020 ( P =.02), role as medical director ( P =.01), and nighttime home call with supervision of in-house ICU fellows ( P =.01).

CONCLUSIONS

Professional fulfillment and work exhaustion in this cross-sectional survey were associated with several demographic and practice characteristics but not COVID-19-related workload, suggesting that COVID-19 workload may not have either positive or negative perceptions on professional fulfillment.

Intraoperative plasma proteomic changes in cardiac surgery: In search of biomarkers of post-operative delirium

PURPOSE

Delirium presents a significant healthcare burden. It complicates post-operative care in up to 50% of cardiac surgical patients with worse outcomes, longer hospital stays and higher cost of care. Moreover, the nature of delirium following cardiac surgery with cardiopulmonary bypass (CPB) remains unclear, the underlying pathobiology is poorly understood, status quo diagnostic methods are subjective, and diagnostic biomarkers are currently lacking.

OBJECTIVE

To identify diagnostic biomarkers of delirium and for insights into possible neuronal pathomechanisms.

EXPERIMENTAL DESIGN

Comparative proteomic analyses were performed on plasma samples from a nested matched cohort of patients who underwent cardiac surgery. Validation by targeted proteomics was performed in an independent set of samples. Biomarkers were assessed for biological functions and diagnostic accuracy.

RESULTS

Forty-seven percent of subjects demonstrated delirium. Of 3803 proteins identified from patient samples by multiplexed quantitative proteomics, 16 were identified as signatures of exposure to CPB, and 11 biomarkers distinguished delirium cases from non-cases (AuROC = 93%). Notable among these biomarkers are C-reactive protein, serum amyloid A-1 and cathepsin-B.

CONCLUSIONS AND CLINICAL RELEVANCE

The interplay of systemic and central inflammatory markers sheds new light on delirium pathogenesis. This work suggests that accurate identification of cases may be achievable using panels of biomarkers.

Timing of invasive mechanical ventilation and death in critically ill adults with COVID-19: A multicenter cohort study

PURPOSE

To investigate if the timing of initiation of invasive mechanical ventilation (IMV) for critically ill patients with COVID-19 is associated with mortality.

MATERIALS AND METHODS

The data for this study were derived from a multicenter cohort study of critically ill adults with COVID-19 admitted to ICUs at 68 hospitals across the US from March 1 to July 1, 2020. We examined the association between early (ICU days 1-2) versus late (ICU days 3-7) initiation of IMV and time-to-death. Patients were followed until the first of hospital discharge, death, or 90 days. We adjusted for confounding using a multivariable Cox model.

RESULTS

Among the 1879 patients included in this analysis (1199 male [63.8%]; median age, 63 [IQR, 53-72] years), 1526 (81.2%) initiated IMV early and 353 (18.8%) initiated IMV late. A total of 644 of the 1526 patients (42.2%) in the early IMV group died, and 180 of the 353 (51.0%) in the late IMV group died (adjusted HR 0.77 [95% CI, 0.65-0.93]).

CONCLUSIONS

In critically ill adults with respiratory failure from COVID-19, early compared to late initiation of IMV is associated with reduced mortality.

Reduced anticoagulation strategy is associated with a lower incidence of intracerebral hemorrhage in COVID-19 patients on extracorporeal membrane oxygenation

BACKGROUND

Optimal anticoagulation strategies for COVID-19 patients with the acute respiratory distress syndrome (ARDS) on venovenous extracorporeal membrane oxygenation (VV ECMO) remain uncertain. A higher incidence of intracerebral hemorrhage (ICH) during VV ECMO support compared to non-COVID-19 viral ARDS patients has been reported, with increased bleeding rates in COVID-19 attributed to both intensified anticoagulation and a disease-specific endotheliopathy. We hypothesized that lower intensity of anticoagulation during VV ECMO would be associated with a lower risk of ICH. In a retrospective, multicenter study from three academic tertiary intensive care units, we included patients with confirmed COVID-19 ARDS requiring VV ECMO support from March 2020 to January 2022. Patients were grouped by anticoagulation exposure into higher intensity, targeting anti-factor Xa activity (anti-Xa) of 0.3-0.4 U/mL, versus lower intensity, targeting anti-Xa 0.15-0.3 U/mL, cohorts. Mean daily doses of unfractionated heparin (UFH) per kg bodyweight and effectively measured daily anti-factor Xa activities were compared between the groups over the first 7 days on ECMO support. The primary outcome was the rate of ICH during VV ECMO support.

RESULTS

141 critically ill COVID-19 patients were included in the study. Patients with lower anticoagulation targets had consistently lower anti-Xa activity values over the first 7 ECMO days (p < 0.001). ICH incidence was lower in patients in the lower anti-Xa group: 4 (8%) vs 32 (34%) events. Accounting for death as a competing event, the adjusted subhazard ratio for the occurrence of ICH was 0.295 (97.5% CI 0.1-0.9, p = 0.044) for the lower anti-Xa compared to the higher anti-Xa group. 90-day ICU survival was higher in patients in the lower anti-Xa group, and ICH was the strongest risk factor associated with mortality (odds ratio [OR] 6.8 [CI 2.1-22.1], p = 0.001).

CONCLUSIONS

For COVID-19 patients on VV ECMO support anticoagulated with heparin, a lower anticoagulation target was associated with a significant reduction in ICH incidence and increased survival.

Proteomics for the Discovery of Clinical Delirium Biomarkers: A Systematic Review of Major Studies

Delirium represents a significant health care burden, diagnosed in more than 2 million elderly Americans each year. In the surgical population, delirium remains the most common complication among elderly patients, and is associated with longer hospital stays, higher costs of care, increased mortality, and functional impairment. The pathomechanism of disease is poorly understood, with current diagnostic approaches somewhat subjective and arbitrary, and definitive diagnostic biomarkers are currently lacking. Despite the recent interest in delirium research, biomarker discovery for it remains new. Most attempts to discover biomarkers are targeted studies that seek to assess the involvement of one or more members of a focused panel of candidates in delirium. For a more unbiased, system-biology view, we searched literature from Medical Literature Analysis and Retrieval System Online (MEDLINE), Cochrane Central, Web of Science, SCOPUS, and Dimensions between 2016 and 2021 for untargeted proteomic discovery studies for biomarkers of delirium conducted on human geriatric subjects. Two reviewers conducted an independent review of all search results and resolved discordance by consensus. From an overall search of 1172 publications, 8 peer-reviewed studies met our defined inclusion criteria. The 370 unique perioperative biomarkers identified in these reports are enriched in pathways involving activation of the immune system, inflammatory response, and the coagulation cascade. The most frequently identified biomarker was interleukin-6 (IL-6). By reviewing the distribution of protein biomarker candidates from these studies, we conclude that a panel of proteins, rather than a single biomarker, would allow for discriminating delirium cases from noncases. The paucity of hypothesis-generating studies in the peer-reviewed literature also suggests that a system-biology view of delirium pathomechanisms has yet to fully emerge.

Meeting Report: First Cardiovascular Outcomes Research in Perioperative Medicine Conference

The first Cardiovascular Outcomes Research in Perioperative Medicine (COR-PM) conference took place on May 13, 2022, in Palm Springs, CA, and online. Here, we: (1) summarize the background, objective, and aims of the COR-PM meeting; (2) describe the conduct of the meeting; and (3) outline future directions for scientific meetings aimed at fostering high-quality clinical research in the broader perioperative medicine community.

Nationwide Clinical Practice Patterns of Anesthesiology Critical Care Physicians: A Survey to Members of the Society of Critical Care Anesthesiologists

BACKGROUND

Despite the growing contributions of critical care anesthesiologists to clinical practice, research, and administrative leadership of intensive care units (ICUs), relatively little is known about the subspecialty-specific clinical practice environment. An understanding of contemporary clinical practice is essential to recognize the opportunities and challenges facing critical care anesthesia, optimize staffing patterns, assess sustainability and satisfaction, and strategically plan for future activity, scope, and training. This study surveyed intensivists who are members of the Society of Critical Care Anesthesiologists (SOCCA) to evaluate practice patterns of critical care anesthesiologists, including compensation, types of ICUs covered, models of overnight ICU coverage, and relationships between these factors. We hypothesized that variability in compensation and practice patterns would be observed between individuals.

METHODS

Board-certified critical care anesthesiologists practicing in the United States were identified using the SOCCA membership distribution list and invited to take a voluntary online survey between May and June 2021. Multiple-choice questions with both single- and multiple-select options were used for answers with categorical data, and adaptive questioning was used to clarify stem-based responses. Respondents were asked to describe practice patterns at their respective institutions and provide information about their demographics, salaries, effort in ICUs, as well as other activities.

RESULTS

A total of 490 participants were invited to take this survey, and 157 (response rate 32%) surveys were completed and analyzed. The majority of respondents were White (73%), male (69%), and younger than 50 years of age (82%). The cardiothoracic/cardiovascular ICU was the most common practice setting, with 69.5% of respondents reporting time working in this unit. Significant variability was observed in ICU practice patterns. Respondents reported spending an equal proportion of their time in clinical practice in the operating rooms and ICUs (median, 40%; interquartile range [IQR], 20%-50%), whereas a smaller proportion-primarily those who completed their training before 2009-reported administrative or research activities. Female respondents reported salaries that were $36,739 less than male respondents; however, this difference was not statistically different, and after adjusting for age and practice type, these differences were less pronounced (-$27,479.79; 95% confidence interval [CI], -$57,232.61 to $2273.03; P = .07).

CONCLUSIONS

These survey data provide a current snapshot of anesthesiology critical care clinical practice patterns in the United States. Our findings may inform decision-making around the initiation and expansion of critical care services and optimal staffing patterns, as well as provide a basis for further work that focuses on intensivist satisfaction and burnout.

Nighttime dexmedetomidine for delirium prevention in non-mechanically ventilated patients after cardiac surgery (MINDDS): A single-centre, parallel-arm, randomised, placebo-controlled superiority trial

BACKGROUND

The delirium-sparing effect of nighttime dexmedetomidine has not been studied after surgery. We hypothesised that a nighttime dose of dexmedetomidine would reduce the incidence of postoperative delirium as compared to placebo.

METHODS

This single-centre, parallel-arm, randomised, placebo-controlled superiority trial evaluated whether a short nighttime dose of intravenous dexmedetomidine (1 μg/kg over 40 min) would reduce the incidence of postoperative delirium in patients 60 years of age or older undergoing elective cardiac surgery with cardiopulmonary bypass. Patients were randomised to receive dexmedetomidine or placebo in a 1:1 ratio. The primary outcome was delirium on postoperative day one. Secondary outcomes included delirium within three days of surgery, 30-, 90-, and 180-day abbreviated Montreal Cognitive Assessment scores, Patient Reported Outcome Measures Information System quality of life scores, and all-cause mortality. The study was registered as NCT02856594 on ClinicalTrials.gov on August 5, 2016, before the enrolment of any participants.

FINDINGS

Of 469 patients that underwent randomisation to placebo (n = 235) or dexmedetomidine (n = 234), 75 met a prespecified drop criterion before the study intervention. Thus, 394 participants (188 dexmedetomidine; 206 placebo) were analysed in the modified intention-to-treat cohort (median age 69 [IQR 64, 74] years; 73.1% male [n = 288]; 26·9% female [n = 106]). Postoperative delirium status on day one was missing for 30 (7.6%) patients. Among those in whom it could be assessed, the primary outcome occurred in 5 of 175 patients (2.9%) in the dexmedetomidine group and 16 of 189 patients (8.5%) in the placebo group (OR 0.32, 95% CI: 0.10-0.83; P = 0.029). A non-significant but higher proportion of participants experienced delirium within three days postoperatively in the placebo group (25/177; 14.1%) compared to the dexmedetomidine group (14/160; 8.8%; OR 0.58; 95% CI, 0.28-1.15). No significant differences between groups were observed in secondary outcomes or safety.

INTERPRETATION

Our findings suggested that in elderly cardiac surgery patients with a low baseline risk of postoperative delirium and extubated within 12 h of ICU admission, a short nighttime dose of dexmedetomidine decreased the incidence of delirium on postoperative day one. Although non-statistically significant, our findings also suggested a clinical meaningful difference in the three-day incidence of postoperative delirium.

FUNDING

National Institute on Aging (R01AG053582).

Anesthetic Preferences for Cardiac Anesthesia: A Survey of the Society of Cardiovascular Anesthesiologists

BACKGROUND

Volatile anesthetics have been historically preferred for cardiac anesthesia, but the evidence for their superiority to intravenous agents is mixed. We conducted a survey to better understand the current state of practice and the rationale behind provider preferences for anesthesia for cardiac surgery with cardiopulmonary bypass. We hypothesized that anesthetic preference would vary considerably among surveyed providers without a clear majority, as would the rationale behind those preferences.

METHODS

Email invitations were sent to members of the Society of Cardiovascular Anesthesiologists, who were asked to identify the anesthetics or sedatives they typically prefer to administer during induction, prebypass, bypass, postbypass, and postoperative periods and why they prefer those agents. Members' beliefs regarding the importance of anesthetics on postoperative outcomes were also assessed.

RESULTS

Invitations were sent on 2 separate dates to 3328 and 3274 members, of whom 689 (21%) responded. The median (interquartile range [IQR]) respondent age was 45 (37-56) years, 79% were men, and 75% were fellowship trained. The most frequently chosen drug for induction was propofol (80%). Isoflurane was the most frequently selected primary agent for the prebypass (57%), bypass (62%), and postbypass periods (50%). Sevoflurane was the second most frequently selected (30%; 17%, and 24%, respectively). Propofol was the third most frequently selected agent for the bypass (14%) and postbypass periods (17%). Ease of use was the most frequently selected reason for administering isoflurane and sevoflurane for each period. During bypass, the second most frequently selected rationale for using isoflurane and sevoflurane was institutional practice. A total of 76% responded that the perfusionist typically delivers the bypass anesthetic. Ischemic preconditioning, organ protection, and postoperative cognitive function were infrequently selected as rationales for preferring the volatile anesthetics. Most respondents (73%) think that anesthetics have organ-protective properties, especially isoflurane (74%) and sevoflurane (59%), and 72% believed that anesthetic choice contributes to patient outcome. The median (IQR) agreement (0 = strongly disagree to 100 = strongly agree) was 72 (63-85) for the statement that "inhaled anesthetics are an optimal maintenance anesthetic for cardiac surgery."

CONCLUSIONS

In a survey of cardiac anesthesiologists, a majority of respondents indicated that they prefer volatile anesthetics for maintenance of anesthesia, that anesthetic selection impacts patient outcomes, and that volatile anesthetics have organ-protective properties. The members' rationales for preferring these agents possibly reflect that practical considerations, such as ease of use, effectiveness, and institutional practice, also influence anesthetic selection during cardiac surgery in addition to considerations such as organ protection.

The Acute Respiratory Distress Syndrome

Acute respiratory distress syndrome (ARDS) defines a clinical entity involving respiratory failure, hypoxemia, and bilateral pulmonary infiltrates on chest X-ray secondary to noncardiogenic pulmonary edema. Pathogenesis requires an initial insult that triggers a systemic inflammatory response, ultimately damaging lung parenchyma. Management is multifaceted, including treatment of the underlying disease process, lung-protective ventilation strategies, methods to prevent patient–ventilator dysynchrony, and strategies to improve ventilator:perfusion matching. Escalation to extracorporeal membrane oxygenation may even be required. Several therapies have not been shown to reduce mortality, including inhaled nitric oxide and high-frequency oscillatory ventilation. The mortality rate is high, and recovery is prolonged. There are many significant areas of ongoing research to better delineate patient, disease, and treatment-related factors that reduce morbidity and mortality in ARDS.

The Effect of Antiseizure Medication Administration on Mortality and Early Posttraumatic Seizures in Critically Ill Older Adults with Traumatic Brain Injury

BACKGROUND

Traumatic brain injury (TBI) is a major cause of morbidity and mortality in the United States. Older adults represent an understudied and growing TBI population. Current Brain Trauma Foundation guidelines support prophylactic antiseizure medication (ASM) administration to reduce the risk of early posttraumatic seizures (within 7 days of injury) in patients with severe TBI. Whether ASM decreases mortality or early seizure risk in this population remains unclear. This study addresses the knowledge gap regarding the impact of ASM administration on the risk of seizure or mortality after TBI in patients more than 65 years of age.

METHODS

This retrospective cohort study used a publicly available data set from the Medical Information Mart for Intensive Care-III from the Massachusetts Institute of Technology. Our cohort included patients 65 years or older with a primary exposure of early ASM administration with TBI resulting in an intensive care unit (ICU) admission in a level I trauma center from 2001 to 2012. A double-robust inverse propensity scale weighted model on the basis of proportional hazard and logistic regression models was created to assess the association between ASM administration and risk of death within 7 days of admission to the ICU. Secondary outcomes included 30-day mortality and 1-year mortality, early posttraumatic seizures, ICU length of stay, and hospital length of stay.

RESULTS

Of 1145 patients 65 years or older with TBI admitted to an ICU, 783 (68.4%) received ASM within the first 24 h. Patients meeting inclusion criteria were predominantly white (83.8%) and were male (52.3%), with a median (interquartile range) age of 81 (74-86) years. TBI severity, classified by Glasgow Coma Score, was predominantly mild (71.2%), followed by moderate (16.8%) and severe (11.3%). Patients who received ASM were less likely to have died at 7 days (adjusted death hazard ratio [HR] = 0.48 [95% confidence interval {CI} 0.28-0.88], P = 0.005), at 30 days (adjusted HR 0.67 [95% CI 0.45-0.99], P = 0.045), and at 1 year (adjusted HR 0.72 [95% CI 0.54-0.97], P = 0.029). Groups were not different in regard to seizure (adjusted seizure odds ratio 1.18 [95% CI 0.61-2.26]) compared with those who did not receive ASM.

CONCLUSIONS

Early ASM administration was associated with reduced mortality at 7 days, 30 days, and 1 year but did not decrease the risk of early seizures among older adults who presented with TBI at an ICU. This benefit was observed in mild, moderate, and severe TBI assessed by Glasgow Coma Score on presentation among patients 65 years old and older and suggests broader recommendations for the use of ASM in older adults who present with TBI of any severity at an ICU.

MUlticenter STudy of tissue plasminogen activator (alteplase) use in COVID‐19 severe respiratory failure (MUST COVID): A retrospective cohort study

Background

Few therapies exist to treat severe COVID‐19 respiratory failure once it develops. Given known diffuse pulmonary microthrombi on autopsy studies of COVID‐19 patients, we hypothesized that tissue plasminogen activator (tPA) may improve pulmonary function in COVID‐19 respiratory failure.

Methods

A multicenter, retrospective, observational study of patients with confirmed COVID‐19 and severe respiratory failure who received systemic tPA (alteplase) was performed. Seventy‐nine adults from seven medical centers were included in the final analysis after institutional review boards' approval; 23 were excluded from analysis because tPA was administered for pulmonary macroembolism or deep venous thrombosis. The primary outcome was improvement in the PaO₂/FiO₂ ratio from baseline to 48 h after tPA. Linear mixed modeling was used for analysis.

Results

tPA was associated with significant PaO₂/FiO₂ improvement at 48 h (estimated paired difference = 23.1 ± 6.7), which was sustained at 72 h (interaction term p < 0.00). tPA administration was also associated with improved National Early Warning Score 2 scores at 24, 48, and 72 h after receiving tPA (interaction term p = 0.00). D‐dimer was significantly elevated immediately after tPA, consistent with lysis of formed clot. Patients with declining respiratory status preceding tPA administration had more marked improvement in PaO₂/FiO₂ ratios than those who had poor but stable (not declining) respiratory status. There was one intracranial hemorrhage, which occurred within 24 h following tPA administration.

Conclusions

These data suggest tPA is associated with significant improvement in pulmonary function in severe COVID‐19 respiratory failure, especially in patients whose pulmonary function is in decline, and has an acceptable safety profile in this patient population.

Bleeding and thrombotic events in adults supported with venovenous extracorporeal membrane oxygenation: an ELSO registry analysis

PURPOSE

This study aimed at analyzing the prevalence, mortality association, and risk factors for bleeding and thrombosis events (BTEs) among adults supported with venovenous extracorporeal membrane oxygenation (VV-ECMO).

METHODS

We queried the Extracorporeal Life Support Organization registry for adults supported with VV-ECMO from 2010 to 2017. Multivariable logistic regression modeling was used to assess the association between BTEs and in-hospital mortality and the predictors of BTEs.

RESULTS

Among 7579 VV-ECMO patients meeting criteria, 40.2% experienced ≥ 1 BTE. Thrombotic events comprised 54.9% of all BTEs and were predominantly ECMO circuit thrombosis. BTE rates decreased significantly over the study period (p < 0.001). The inpatient mortality rate was 34.9%. Bleeding events (1.69 [1.49-1.93]) were more strongly associated with in-hospital mortality than thrombotic events (1.23 [1.08-1.41]) p < 0.01 for both. The BTEs most strongly associated with mortality were ischemic stroke (4.50 [2.55-7.97]) and medical bleeding, including intracranial (5.71 [4.02-8.09]), pulmonary (2.02 [1.54-2.67]), and gastrointestinal (1.54 [1.2-1.98]) hemorrhage, all p < 0.01. Risk factors for bleeding included acute kidney injury and pre-ECMO vasopressor support and for thrombosis were higher weight, multisite cannulation, pre-ECMO arrest, and higher PaCO₂ at ECMO initiation. Longer time on ECMO, younger age, higher pH, and earlier year of support were associated with bleeding and thrombosis.

CONCLUSIONS

Although decreasing over time, BTEs remain common during VV-ECMO and have a strong, cumulative association with in-hospital mortality. Thrombotic events are more frequent, but bleeding carries a higher risk of inpatient mortality. Differential risk factors for bleeding and thrombotic complications exist, raising the possibility of a tailored approach to VV-ECMO management.

Limited TCR repertoire and ENTPD1 dysregulation mark late-stage COVID-19

T cell exhaustion and dysfunction are hallmarks of severe COVID-19. To gain insights into the pathways underlying these alterations, we performed a comprehensive transcriptome analysis of peripheral-blood-mononuclear-cells (PBMCs), spleen, lung, kidney, liver, and heart obtained at autopsy from COVID-19 patients and matched controls, using the nCounter CAR-T-Characterization panel. We found substantial gene alterations in COVID-19-impacted organs, especially the lung where altered TCR repertoires are noted. Reduced TCR repertoires are also observed in PBMCs of severe COVID-19 patients. ENTPD1/CD39, an ectoenzyme defining exhausted T-cells, is upregulated in the lung, liver, spleen, and PBMCs of severe COVID-19 patients where expression positively correlates with markers of vasculopathy. Heightened ENTPD1/CD39 is paralleled by elevations in STAT-3 and HIF-1α transcription factors; and by markedly reduced CD39-antisense-RNA, a long-noncoding-RNA negatively regulating ENTPD1/CD39 at the post-transcriptional level. Limited TCR repertoire and aberrant regulation of ENTPD1/CD39 could have permissive roles in COVID-19 progression and indicate potential therapeutic targets to reverse disease.

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Transcriptome profiling of COVID-19 autoptic tissue and PBMC was carried out

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There is limited TCR repertoire in lung, kidney and PBMC of severe COVID-19 cases

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There are increased CD39 levels in PBMC of severe COVID-19 patients

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High HIF-1a and STAT-3 and low CD39-antisense might be linked with CD39 increase

Study of Alteplase for Respiratory Failure in SARS-CoV-2 COVID-19: A Vanguard Multicenter, Rapidly Adaptive, Pragmatic, Randomized Controlled Trial

Background

Pulmonary vascular microthrombi are a proposed mechanism of COVID-19 respiratory failure. We hypothesized that early administration of tissue plasminogen activator (tPA) followed by therapeutic heparin would improve pulmonary function in these patients.

Research Question

Does tPA improve pulmonary function in severe COVID-19 respiratory failure, and is it safe?

Study Design and Methods

Adults with COVID-19-induced respiratory failure were randomized from May14, 2020 through March 3, 2021, in two phases. Phase 1 (n = 36) comprised a control group (standard-of-care treatment) vs a tPA bolus (50-mg tPA IV bolus followed by 7 days of heparin; goal activated partial thromboplastin time [aPTT], 60-80 s) group. Phase 2 (n = 14) comprised a control group vs a tPA drip (50-mg tPA IV bolus, followed by tPA drip 2 mg/h plus heparin 500 units/h over 24 h, then heparin to maintain aPTT of 60-80 s for 7 days) group. Patients were excluded from enrollment if they had not undergone a neurologic examination or cross-sectional brain imaging within the previous 4.5 h to rule out stroke and potential for hemorrhagic conversion. The primary outcome was Pao₂ to Fio₂ ratio improvement from baseline at 48 h after randomization. Secondary outcomes included Pao₂ to Fio₂ ratio improvement of > 50% or Pao₂ to Fio₂ ratio of ≥ 200 at 48 h (composite outcome), ventilator-free days (VFD), and mortality.

Results

Fifty patients were randomized: 17 in the control group and 19 in the tPA bolus group in phase 1 and eight in the control group and six in the tPA drip group in phase 2. No severe bleeding events occurred. In the tPA bolus group, the Pao₂ to Fio₂ ratio values were significantly (P < .017) higher than baseline at 6 through 168 h after randomization; the control group showed no significant improvements. Among patients receiving a tPA bolus, the percent change of Pao₂ to Fio₂ ratio at 48 h (16.9% control [interquartile range (IQR), –8.3% to 36.8%] vs 29.8% tPA bolus [IQR, 4.5%-88.7%]; P = .11), the composite outcome (11.8% vs 47.4%; P = .03), VFD (0.0 [IQR, 0.0-9.0] vs 12.0 [IQR, 0.0-19.0]; P = .11), and in-hospital mortality (41.2% vs 21.1%; P = .19) did not reach statistically significant differences when compared with those of control participants. The patients who received a tPA drip did not experience benefit.

Interpretation

The combination of tPA bolus plus heparin is safe in severe COVID-19 respiratory failure. A phase 3 study is warranted given the improvements in oxygenation and promising observations in VFD and mortality.

Trial Registry

ClinicalTrials.gov; No.: NCT04357730; URL: www.clinicaltrials.gov

Serum Proteomics of Older Patients Undergoing Major Cardiac Surgery: Identification of Biomarkers Associated With Postoperative Delirium

Background

Postoperative delirium (POD) is an acute altered mental state commonly encountered after cardiac surgery. The pathophysiological mechanisms underlying POD remain unclear. We aimed to identify circulating proteins significantly altered after major cardiac surgery with cardiopulmonary bypass (CPB). We also aimed to enable inferences on associations with POD.

Methods

Serum and whole blood samples were collected before CPB (n = 16 patients; n = 8 with POD) and again from the same patients on postoperative day 1. All patients were clinically evaluated for POD on postoperative days 1–3. An aptamer-based proteomics platform (SOMAscan) was used to quantify serum protein abundance in patients with POD compared with non-POD controls. We also performed a lipopolysaccharide (LPS)-based in vitro functional analysis (TruCulture) on whole blood samples from patients with POD and non-POD controls to approximate surgical stress. Cytokine levels were determined using a Luminex immunoassay.

Results

Cardiac surgery with CPB resulted in a significant (p_adj < 0.01) change in 48.8% (637 out of 1,305) of proteins detected by SOMAscan. Gene set enrichment showed that the most impacted biological processes involved myeloid cell activation. Specifically, activation and degranulation of neutrophils were the top five highest-scoring processes. Pathway analyses with the Kyoto Encyclopedia of Genes and Genomes (KEGG) showed that metabolic enzymes, particularly those of glycolysis, were elevated in serum concentration after surgery. Several proteins were significantly increased postoperatively in patients diagnosed with POD relative to the non-POD controls, with interleukin-6 (IL-6) showing the greatest fold-change. LPS stimulation of whole blood samples confirmed these findings. Linear regression analysis showed a highly significant correlation between Confusion Assessment Method (CAM) scores and CPB-mediated changes in cGMP-inhibited 3′,5′-cyclic phosphodiesterase A (PDE3A).

Conclusions

Cardiac surgery with CPB resulted in inflammasome changes accompanied by unexpected increases in metabolic pathways. In exploratory analyses, we found that POD was associated with changes in the expression level of various proteins, most notably IL-6 and PDE3A. This study and ongoing protein biomarker studies will likely help quantify risk or confirm the diagnosis for POD and increase understanding of its pathophysiological mechanisms.

Serum Proteomics of Older Patients Undergoing Major Cardiac Surgery: Identification of Biomarkers Associated With Postoperative Delirium

BACKGROUND

Postoperative delirium (POD) is an acute altered mental state commonly encountered after cardiac surgery. The pathophysiological mechanisms underlying POD remain unclear. We aimed to identify circulating proteins significantly altered after major cardiac surgery with cardiopulmonary bypass (CPB). We also aimed to enable inferences on associations with POD.

METHODS

Serum and whole blood samples were collected before CPB (n = 16 patients; n = 8 with POD) and again from the same patients on postoperative day 1. All patients were clinically evaluated for POD on postoperative days 1-3. An aptamer-based proteomics platform (SOMAscan) was used to quantify serum protein abundance in patients with POD compared with non-POD controls. We also performed a lipopolysaccharide (LPS)-based in vitro functional analysis (TruCulture) on whole blood samples from patients with POD and non-POD controls to approximate surgical stress. Cytokine levels were determined using a Luminex immunoassay.

RESULTS

Cardiac surgery with CPB resulted in a significant (p_adj < 0.01) change in 48.8% (637 out of 1,305) of proteins detected by SOMAscan. Gene set enrichment showed that the most impacted biological processes involved myeloid cell activation. Specifically, activation and degranulation of neutrophils were the top five highest-scoring processes. Pathway analyses with the Kyoto Encyclopedia of Genes and Genomes (KEGG) showed that metabolic enzymes, particularly those of glycolysis, were elevated in serum concentration after surgery. Several proteins were significantly increased postoperatively in patients diagnosed with POD relative to the non-POD controls, with interleukin-6 (IL-6) showing the greatest fold-change. LPS stimulation of whole blood samples confirmed these findings. Linear regression analysis showed a highly significant correlation between Confusion Assessment Method (CAM) scores and CPB-mediated changes in cGMP-inhibited 3',5'-cyclic phosphodiesterase A (PDE3A).

CONCLUSIONS

Cardiac surgery with CPB resulted in inflammasome changes accompanied by unexpected increases in metabolic pathways. In exploratory analyses, we found that POD was associated with changes in the expression level of various proteins, most notably IL-6 and PDE3A. This study and ongoing protein biomarker studies will likely help quantify risk or confirm the diagnosis for POD and increase understanding of its pathophysiological mechanisms.

Machine Learning Prediction of Death in Critically Ill Patients With Coronavirus Disease 2019

OBJECTIVES

Critically ill patients with coronavirus disease 2019 have variable mortality. Risk scores could improve care and be used for prognostic enrichment in trials. We aimed to compare machine learning algorithms and develop a simple tool for predicting 28-day mortality in ICU patients with coronavirus disease 2019.

DESIGN

This was an observational study of adult patients with coronavirus disease 2019. The primary outcome was 28-day inhospital mortality. Machine learning models and a simple tool were derived using variables from the first 48 hours of ICU admission and validated externally in independent sites and temporally with more recent admissions. Models were compared with a modified Sequential Organ Failure Assessment score, National Early Warning Score, and CURB-65 using the area under the receiver operating characteristic curve and calibration.

SETTING

Sixty-eight U.S. ICUs.

PATIENTS

Adults with coronavirus disease 2019 admitted to 68 ICUs in the United States between March 4, 2020, and June 29, 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The study included 5,075 patients, 1,846 (36.4%) of whom died by day 28. eXtreme Gradient Boosting had the highest area under the receiver operating characteristic curve in external validation (0.81) and was well-calibrated, while k-nearest neighbors were the lowest performing machine learning algorithm (area under the receiver operating characteristic curve 0.69). Findings were similar with temporal validation. The simple tool, which was created using the most important features from the eXtreme Gradient Boosting model, had a significantly higher area under the receiver operating characteristic curve in external validation (0.78) than the Sequential Organ Failure Assessment score (0.69), National Early Warning Score (0.60), and CURB-65 (0.65; p < 0.05 for all comparisons). Age, number of ICU beds, creatinine, lactate, arterial pH, and Pao2/Fio2 ratio were the most important predictors in the eXtreme Gradient Boosting model.

CONCLUSIONS

eXtreme Gradient Boosting had the highest discrimination overall, and our simple tool had higher discrimination than a modified Sequential Organ Failure Assessment score, National Early Warning Score, and CURB-65 on external validation. These models could be used to improve triage decisions and clinical trial enrichment.

Aberrant CD39 levels and regulation mark COVID-19 late stage

Previous studies have reported immune cell exhaustion and perturbed T-cell immunity in novel-coronavirus-disease-19 (COVID-19). Heightened levels of CD39, an ectonucleotidase key to immunoregulation, are detected in CD4 and CD8 T-cells during viral infection where they correlate with worse disease outcome.

We performed a comprehensive transcriptome analysis of T-cell related gene pathways in PBMCs from 18 COVID-19 patients (6 convalescent, 6 with moderate disease and 6 with severe disease) and 6 healthy controls (HC); and in formalin-fixed autoptic tissue, obtained from the spleen, lung, kidney, liver and heart of 5 COVID-19 cases and 2 controls. Analysis was performed using nCounter CAR-T characterization panel (NanoString).

Our data show that in COVID-19 tissues there is a marked decrease in TCR diversity that is also present in PBMCs of severe patients, when compared with patients with moderate disease, convalescents and HC. A similar pattern is also noted when analyzing PBMCs for TCR signaling, Th1, Th17 and Treg-related transcripts. Heightened CD39 transcripts are detected in lung, liver and spleen of COVID-19 patients as well as in PBMCs obtained from patients with severe disease. A similar trend is observed for STAT-3, and HIF-1alpha, transcription factors that regulate CD39. Notably, CD39-AS RNA, a lncRNA that regulates CD39 at the post-transcriptional level, is markedly reduced in severe COVID-19 patients.

In conclusion, our data indicate systemic and local alterations in T-cell immunity in COVID-19. Aberrantly high levels of CD39 and related transcription factors and concomitant decreases in CD39-AS RNA in the late stage of disease suggest a role for CD39 and purinergic signaling in COVID-19 progression.

d-dimer and Death in Critically Ill Patients With Coronavirus Disease 2019

OBJECTIVES

Hypercoagulability may be a key mechanism for acute organ injury and death in patients with severe coronavirus disease 2019, but the relationship between elevated plasma levels of d-dimer, a biomarker of coagulation activation, and mortality has not been rigorously studied. We examined the independent association between d-dimer and death in critically ill patients with coronavirus disease 2019.

DESIGN

Multicenter cohort study.

SETTING

ICUs at 68 hospitals across the United States.

PATIENTS

Critically ill adults with coronavirus disease 2019 admitted to ICUs between March 4, 2020, and May 25, 2020, with a measured d-dimer concentration on ICU day 1 or 2.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary exposure was the highest normalized d-dimer level (assessed in four categories: < 2×, 2-3.9×, 4-7.9×, and ≥ 8× the upper limit of normal) on ICU day 1 or 2. The primary endpoint was 28-day mortality. Multivariable logistic regression was used to adjust for confounders. Among 3,418 patients (63.1% male; median age 62 yr [interquartile range, 52-71 yr]), 3,352 (93.6%) had a d-dimer concentration above the upper limit of normal. A total of 1,180 patients (34.5%) died within 28 days. Patients in the highest compared with lowest d-dimer category had a 3.11-fold higher odds of death (95% CI, 2.56-3.77) in univariate analyses, decreasing to a 1.81-fold increased odds of death (95% CI, 1.43-2.28) after multivariable adjustment for demographics, comorbidities, and illness severity. Further adjustment for therapeutic anticoagulation did not meaningfully attenuate this relationship (odds ratio, 1.73; 95% CI, 1.36-2.19).

CONCLUSIONS

In a large multicenter cohort study of critically ill patients with coronavirus disease 2019, higher d-dimer levels were independently associated with a greater risk of death.

Thrombosis, Bleeding, and the Observational Effect of Early Therapeutic Anticoagulation on Survival in Critically Ill Patients With COVID-19

BACKGROUND

Hypercoagulability may be a key mechanism of death in patients with coronavirus disease 2019 (COVID-19).

OBJECTIVE

To evaluate the incidence of venous thromboembolism (VTE) and major bleeding in critically ill patients with COVID-19 and examine the observational effect of early therapeutic anticoagulation on survival.

DESIGN

In a multicenter cohort study of 3239 critically ill adults with COVID-19, the incidence of VTE and major bleeding within 14 days after intensive care unit (ICU) admission was evaluated. A target trial emulation in which patients were categorized according to receipt or no receipt of therapeutic anticoagulation in the first 2 days of ICU admission was done to examine the observational effect of early therapeutic anticoagulation on survival. A Cox model with inverse probability weighting to adjust for confounding was used.

SETTING

67 hospitals in the United States.

PARTICIPANTS

Adults with COVID-19 admitted to a participating ICU.

MEASUREMENTS

Time to death, censored at hospital discharge, or date of last follow-up.

RESULTS

Among the 3239 patients included, the median age was 61 years (interquartile range, 53 to 71 years), and 2088 (64.5%) were men. A total of 204 patients (6.3%) developed VTE, and 90 patients (2.8%) developed a major bleeding event. Independent predictors of VTE were male sex and higher D-dimer level on ICU admission. Among the 2809 patients included in the target trial emulation, 384 (11.9%) received early therapeutic anticoagulation. In the primary analysis, during a median follow-up of 27 days, patients who received early therapeutic anticoagulation had a similar risk for death as those who did not (hazard ratio, 1.12 [95% CI, 0.92 to 1.35]).

LIMITATION

Observational design.

CONCLUSION

Among critically ill adults with COVID-19, early therapeutic anticoagulation did not affect survival in the target trial emulation.

PRIMARY FUNDING SOURCE

None.

Intraoperative Oxygen Concentration and Neurocognition after Cardiac Surgery

BACKGROUND

Despite evidence suggesting detrimental effects of perioperative hyperoxia, hyperoxygenation remains commonplace in cardiac surgery. Hyperoxygenation may increase oxidative damage and neuronal injury leading to potential differences in postoperative neurocognition. Therefore, this study tested the primary hypothesis that intraoperative normoxia, as compared to hyperoxia, reduces postoperative cognitive dysfunction in older patients having cardiac surgery.

METHODS

A randomized double-blind trial was conducted in patients aged 65 yr or older having coronary artery bypass graft surgery with cardiopulmonary bypass. A total of 100 patients were randomized to one of two intraoperative oxygen delivery strategies. Normoxic patients (n = 50) received a minimum fraction of inspired oxygen of 0.35 to maintain a Pao2 above 70 mmHg before and after cardiopulmonary bypass and between 100 and 150 mmHg during cardiopulmonary bypass. Hyperoxic patients (n = 50) received a fraction of inspired oxygen of 1.0 throughout surgery, irrespective of Pao2 levels. The primary outcome was neurocognitive function measured on postoperative day 2 using the Telephonic Montreal Cognitive Assessment. Secondary outcomes included neurocognitive function at 1, 3, and 6 months, as well as postoperative delirium, mortality, and durations of mechanical ventilation, intensive care unit stay, and hospital stay.

RESULTS

The median age was 71 yr (interquartile range, 68 to 75), and the median baseline neurocognitive score was 17 (16 to 19). The median intraoperative Pao2 was 309 (285 to 352) mmHg in the hyperoxia group and 153 (133 to 168) mmHg in the normoxia group (P < 0.001). The median Telephonic Montreal Cognitive Assessment score on postoperative day 2 was 18 (16 to 20) in the hyperoxia group and 18 (14 to 20) in the normoxia group (P = 0.42). Neurocognitive function at 1, 3, and 6 months, as well as secondary outcomes, were not statistically different between groups.

CONCLUSIONS

In this randomized controlled trial, intraoperative normoxia did not reduce postoperative cognitive dysfunction when compared to intraoperative hyperoxia in older patients having cardiac surgery. Although the optimal intraoperative oxygenation strategy remains uncertain, the results indicate that intraoperative hyperoxia does not worsen postoperative cognition after cardiac surgery.

EDITOR’S PERSPECTIVE

Association Between Early Treatment With Tocilizumab and Mortality Among Critically Ill Patients With COVID-19

IMPORTANCE

Therapies that improve survival in critically ill patients with coronavirus disease 2019 (COVID-19) are needed. Tocilizumab, a monoclonal antibody against the interleukin 6 receptor, may counteract the inflammatory cytokine release syndrome in patients with severe COVID-19 illness.

OBJECTIVE

To test whether tocilizumab decreases mortality in this population.

DESIGN, SETTING, AND PARTICIPANTS

The data for this study were derived from a multicenter cohort study of 4485 adults with COVID-19 admitted to participating intensive care units (ICUs) at 68 hospitals across the US from March 4 to May 10, 2020. Critically ill adults with COVID-19 were categorized according to whether they received or did not receive tocilizumab in the first 2 days of admission to the ICU. Data were collected retrospectively until June 12, 2020. A Cox regression model with inverse probability weighting was used to adjust for confounding.

EXPOSURES

Treatment with tocilizumab in the first 2 days of ICU admission.

MAIN OUTCOMES AND MEASURES

Time to death, compared via hazard ratios (HRs), and 30-day mortality, compared via risk differences.

RESULTS

Among the 3924 patients included in the analysis (2464 male [62.8%]; median age, 62 [interquartile range {IQR}, 52-71] years), 433 (11.0%) received tocilizumab in the first 2 days of ICU admission. Patients treated with tocilizumab were younger (median age, 58 [IQR, 48-65] vs 63 [IQR, 52-72] years) and had a higher prevalence of hypoxemia on ICU admission (205 of 433 [47.3%] vs 1322 of 3491 [37.9%] with mechanical ventilation and a ratio of partial pressure of arterial oxygen to fraction of inspired oxygen of <200 mm Hg) than patients not treated with tocilizumab. After applying inverse probability weighting, baseline and severity-of-illness characteristics were well balanced between groups. A total of 1544 patients (39.3%) died, including 125 (28.9%) treated with tocilizumab and 1419 (40.6%) not treated with tocilizumab. In the primary analysis, during a median follow-up of 27 (IQR, 14-37) days, patients treated with tocilizumab had a lower risk of death compared with those not treated with tocilizumab (HR, 0.71; 95% CI, 0.56-0.92). The estimated 30-day mortality was 27.5% (95% CI, 21.2%-33.8%) in the tocilizumab-treated patients and 37.1% (95% CI, 35.5%-38.7%) in the non-tocilizumab-treated patients (risk difference, 9.6%; 95% CI, 3.1%-16.0%).

CONCLUSIONS AND RELEVANCE

Among critically ill patients with COVID-19 in this cohort study, the risk of in-hospital mortality in this study was lower in patients treated with tocilizumab in the first 2 days of ICU admission compared with patients whose treatment did not include early use of tocilizumab. However, the findings may be susceptible to unmeasured confounding, and further research from randomized clinical trials is needed.

Prevalence of Clostridioides difficile Infection in Critically Ill Patients with Extreme Leukocytosis and Diarrhea

While early empiric antibiotic therapy is beneficial for patients presenting with sepsis, the presentation of sepsis from Clostridioides difficile (formerly Clostridium difficile) infection (CDI) has not been well studied in large cohorts. We sought to determine whether the combination of extreme leukocytosis and diarrhea was strongly predictive of CDI in a cohort of 8659 patients admitted to the intensive care unit. We found that CDI was present in 15.0% (95% CI, 12.1–18.3%) of patients with extreme leukocytosis and diarrhea and that mortality for those with CDI, diarrhea, and extreme leukocytosis was 33.8% (95% CI, 23.2–44.3%). These data support consideration of empiric treatment for CDI in unstable critically ill patients with extreme leukocytosis and diarrhea, along with treatment of other possible sources of sepsis as appropriate. Empiric treatment for CDI can usually be discontinued promptly, along with narrowing of other broad-spectrum antimicrobial coverage, if a sensitive C. difficile test is negative.

Interventional Pulmonology: A Brave New World

Interventional pulmonology is a dynamic and evolving field in respiratory medicine. Advances have improved the ability to diagnose and manage diseases of the airways. A shift toward early detection of malignant disease has generated a focus on innovative diagnostic techniques. With patient populations living longer with malignant and benign diseases, the role for interventional bronchoscopy has grown. In cancer groups, novel immunotherapies have improved the prospects of clinical outcomes and reignited a focus on optimizing patient performance status to enable access to anticancer therapy. This review discusses current and emerging diagnostic modalities and therapeutic approaches available to manage airway diseases.

Veno-venous extracorporeal membrane oxygenation allocation in the COVID-19 pandemic

Rapid global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the resultant clinical illness, coronavirus disease 2019 (COVID-19), drove the World Health Organization to declare COVID-19 a pandemic. Veno-venous Extra-Corporeal Membrane Oxygenation (VV-ECMO) is an established therapy for management of patients demonstrating the most severe forms of hypoxemic respiratory failure from COVID-19. However, features of COVID-19 pathophysiology and necessary length of treatment present distinct challenges for utilization of VV-ECMO within the current healthcare emergency. In addition, growing allocation concerns due to capacity and cost present significant challenges. Ethical and legal aspects pertinent to triage of this resource-intensive, but potentially life-saving, therapy in the setting of the COVID-19 pandemic are reviewed here. Given considerations relevant to VV-ECMO use, additional emphasis has been placed on emerging hospital resource scarcity and disproportionate representation of healthcare workers among the ill. Considerations are also discussed surrounding withdrawal of VV-ECMO and the role for early communication as well as consultation from palliative care teams and local ethics committees. In discussing how to best manage these issues in the COVID-19 pandemic at present, we identify gaps in the literature and policy important to clinicians as this crisis continues.

•

VV-ECMO may successfully treat respiratory failure due to COVID-19.

•

The coronavirus pandemic necessitates judicious use of this resource-intensive therapy.

•

Unique features of COVID-19, including isolation from surrogates, present challenges.

•

Providers face difficult triage decisions that must be communicated appropriately.

•

We review available resources and support tools for clinicians considering VV-ECMO.

Outcomes of critically ill solid organ transplant patients with COVID-19 in the United States

National data on patient characteristics, treatment, and outcomes of critically ill coronavirus disease 2019 (COVID-19) solid organ transplant (SOT) patients are limited. We analyzed data from a multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units (ICUs) at 68 hospitals across the United States from March 4 to May 8, 2020. From 4153 patients, we created a propensity score matched cohort of 386 patients, including 98 SOT patients and 288 non-SOT patients. We used a binomial generalized linear model (log-binomial model) to examine the association of SOT status with death and other clinical outcomes. Among the 386 patients, the median age was 60 years, 72% were male, and 41% were black. Death within 28 days of ICU admission was similar in SOT and non-SOT patients (40% and 43%, respectively; relative risk [RR] 0.92; 95% confidence interval [CI]: 0.70-1.22). Other outcomes and requirement for organ support including receipt of mechanical ventilation, development of acute respiratory distress syndrome, and receipt of vasopressors were also similar between groups. There was a trend toward higher risk of acute kidney injury requiring renal replacement therapy in SOT vs. non-SOT patients (37% vs. 27%; RR [95% CI]: 1.34 [0.97-1.85]). Death and organ support requirement were similar between SOT and non-SOT critically ill patients with COVID-19.

Factors Associated With Death in Critically Ill Patients With Coronavirus Disease 2019 in the US

Importance

The US is currently an epicenter of the coronavirus disease 2019 (COVID-19) pandemic, yet few national data are available on patient characteristics, treatment, and outcomes of critical illness from COVID-19.

Objectives

To assess factors associated with death and to examine interhospital variation in treatment and outcomes for patients with COVID-19.

Design, Setting, and Participants

This multicenter cohort study assessed 2215 adults with laboratory-confirmed COVID-19 who were admitted to intensive care units (ICUs) at 65 hospitals across the US from March 4 to April 4, 2020.

Exposures

Patient-level data, including demographics, comorbidities, and organ dysfunction, and hospital characteristics, including number of ICU beds.

Main Outcomes and Measures

The primary outcome was 28-day in-hospital mortality. Multilevel logistic regression was used to evaluate factors associated with death and to examine interhospital variation in treatment and outcomes.

Results

A total of 2215 patients (mean [SD] age, 60.5 [14.5] years; 1436 [64.8%] male; 1738 [78.5%] with at least 1 chronic comorbidity) were included in the study. At 28 days after ICU admission, 784 patients (35.4%) had died, 824 (37.2%) were discharged, and 607 (27.4%) remained hospitalized. At the end of study follow-up (median, 16 days; interquartile range, 8-28 days), 875 patients (39.5%) had died, 1203 (54.3%) were discharged, and 137 (6.2%) remained hospitalized. Factors independently associated with death included older age (≥80 vs <40 years of age: odds ratio [OR], 11.15; 95% CI, 6.19-20.06), male sex (OR, 1.50; 95% CI, 1.19-1.90), higher body mass index (≥40 vs <25: OR, 1.51; 95% CI, 1.01-2.25), coronary artery disease (OR, 1.47; 95% CI, 1.07-2.02), active cancer (OR, 2.15; 95% CI, 1.35-3.43), and the presence of hypoxemia (Pao2:Fio2<100 vs ≥300 mm Hg: OR, 2.94; 95% CI, 2.11-4.08), liver dysfunction (liver Sequential Organ Failure Assessment score of 2-4 vs 0: OR, 2.61; 95% CI, 1.30-5.25), and kidney dysfunction (renal Sequential Organ Failure Assessment score of 4 vs 0: OR, 2.43; 95% CI, 1.46-4.05) at ICU admission. Patients admitted to hospitals with fewer ICU beds had a higher risk of death (<50 vs ≥100 ICU beds: OR, 3.28; 95% CI, 2.16-4.99). Hospitals varied considerably in the risk-adjusted proportion of patients who died (range, 6.6%-80.8%) and in the percentage of patients who received hydroxychloroquine, tocilizumab, and other treatments and supportive therapies.

Conclusions and Relevance

This study identified demographic, clinical, and hospital-level risk factors that may be associated with death in critically ill patients with COVID-19 and can facilitate the identification of medications and supportive therapies to improve outcomes.

In-hospital cardiac arrest in critically ill patients with covid-19: multicenter cohort study

OBJECTIVES

To estimate the incidence, risk factors, and outcomes associated with in-hospital cardiac arrest and cardiopulmonary resuscitation in critically ill adults with coronavirus disease 2019 (covid-19).

DESIGN

Multicenter cohort study.

SETTING

Intensive care units at 68 geographically diverse hospitals across the United States.

PARTICIPANTS

Critically ill adults (age ≥18 years) with laboratory confirmed covid-19.

MAIN OUTCOME MEASURES

In-hospital cardiac arrest within 14 days of admission to an intensive care unit and in-hospital mortality.

RESULTS

Among 5019 critically ill patients with covid-19, 14.0% (701/5019) had in-hospital cardiac arrest, 57.1% (400/701) of whom received cardiopulmonary resuscitation. Patients who had in-hospital cardiac arrest were older (mean age 63 (standard deviation 14) v 60 (15) years), had more comorbidities, and were more likely to be admitted to a hospital with a smaller number of intensive care unit beds compared with those who did not have in-hospital cardiac arrest. Patients who received cardiopulmonary resuscitation were younger than those who did not (mean age 61 (standard deviation 14) v 67 (14) years). The most common rhythms at the time of cardiopulmonary resuscitation were pulseless electrical activity (49.8%, 199/400) and asystole (23.8%, 95/400). 48 of the 400 patients (12.0%) who received cardiopulmonary resuscitation survived to hospital discharge, and only 7.0% (28/400) survived to hospital discharge with normal or mildly impaired neurological status. Survival to hospital discharge differed by age, with 21.2% (11/52) of patients younger than 45 years surviving compared with 2.9% (1/34) of those aged 80 or older.

CONCLUSIONS

Cardiac arrest is common in critically ill patients with covid-19 and is associated with poor survival, particularly among older patients.

Effect of midodrine versus placebo on time to vasopressor discontinuation in patients with persistent hypotension in the intensive care unit (MIDAS): an international randomised clinical trial

PURPOSE

ICU discharge is often delayed by a requirement for intravenous vasopressor medications to maintain normotension. We hypothesised that the administration of midodrine, an oral α₁-adrenergic agonist, as adjunct to standard treatment shortens the duration of intravenous vasopressor requirement.

METHODS

In this multicentre, randomised, controlled trial including three tertiary referral hospitals in the US and Australia, we enrolled adult patients with hypotension requiring a single-agent intravenous vasopressor for ≥ 24 h. Subjects received oral midodrine (20 mg) or placebo every 8 h in addition to standard care until cessation of intravenous vasopressors, ICU discharge, or occurrence of adverse events. The primary outcome was time to vasopressor discontinuation. Secondary outcomes included time to ICU discharge readiness, ICU and hospital lengths of stay, and ICU readmission rates.

RESULTS

Between October 2012 and June 2019, 136 participants were randomised, of whom 132 received the allocated intervention and were included in the analysis (modified intention-to-treat approach). Time to vasopressor discontinuation was not different between midodrine and placebo groups (median [IQR], 23.5 [10-54] vs 22.5 [10.4-40] h; difference, 1 h; 95% CI - 10.4 to 12.3 h; p = 0.62). No differences in secondary endpoints were observed. Bradycardia occurred more often after midodrine administration (5 [7.6%] vs 0 [0%], p = 0.02).

CONCLUSION

Midodrine did not accelerate liberation from intravenous vasopressors and was not effective for the treatment of hypotension in critically ill patients.

Perioperative Considerations for Tracheostomies in the Era of COVID-19

The morbidity, mortality, and blistering pace of transmission of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to an unprecedented worldwide health crisis. Coronavirus disease 2019 (COVID-19), the disease produced by SARS-CoV-2 infection, is remarkable for persistent, severe respiratory failure requiring mechanical ventilation that places considerable strain on critical care resources. Because recovery from COVID-19-associated respiratory failure can be prolonged, tracheostomy may facilitate patient management and optimize the use of mechanical ventilators. Several important considerations apply to plan tracheostomies for COVID-19-infected patients. After performing a literature review of tracheostomies during the severe acute respiratory syndrome (SARS) and Middle East Respiratory Syndrome (MERS) outbreaks, we synthesized important learning points from these experiences and suggested an approach for perioperative teams involved in these procedures during the COVID-19 pandemic. Multidisciplinary teams should be involved in decisions regarding timing and appropriateness of the procedure. As the theoretical risk of disease transmission is increased during aerosol-generating procedures (AGPs), stringent infectious precautions are warranted. Personal protective equipment (PPE) should be available and worn by all personnel present during tracheostomy. The number of people in the room should be limited to those absolutely necessary. Using the most experienced available operators will minimize the total time that staff is exposed to an infectious aerosolized environment. An approach that secures the airway in the safest and quickest manner will minimize the time any part of the airway is open to the environment. Deep neuromuscular blockade (train-of-four ratio = 0) will facilitate surgical exposure and prevent aerosolization due to patient movement or coughing. For percutaneous tracheostomies, the bronchoscopist should be able to reintubate if needed. Closed-loop communication must occur at all times among members of the team. If possible, after tracheostomy is performed, waiting until the patient is virus-free before changing the cannula or downsizing may reduce the chances of health care worker infection. Tracheostomies in COVID-19 patients present themselves as extremely high risk for all members of the procedural team. To mitigate risk, systematic meticulous planning of each procedural step is warranted along with strict adherence to local/institutional protocols.

Economic Burden of Postoperative Neurocognitive Disorders Among US Medicare Patients

IMPORTANCE

Postoperative neurocognitive disorders (PNDs) after surgical procedures are common and may be associated with increased health care expenditures.

OBJECTIVE

To quantify the economic burden associated with a PND diagnosis in 1 year following surgical treatment among older patients in the United States.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used claims data from the Bundled Payments for Care Improvement Advanced Model from 4285 hospitals that submitted Medicare Fee-for-service (FFS) claims between January 2013 and December 2016. All Medicare patients aged 65 years or older who underwent an inpatient hospital admission associated with a surgical procedure, did not experience a PND before index admission, and were not undergoing dialysis or concurrently enrolled in Medicaid were included. Data were analyzed from October 2019 and May 2020.

EXPOSURES

PND, defined as an International Classification of Diseases, Ninth or Tenth Revision, diagnosis of delirium, mild cognitive impairment, or dementia within 1 year of discharge from the index surgical admission.

MAIN OUTCOMES AND MEASURES

The primary outcome was total inflation-adjusted Medicare postacute care payments within 1 year after the index surgical procedure.

RESULTS

A total of 2 380 473 patients (mean [SD] age, 75.36 (7.31) years; 1 336 736 [56.1%] women) who underwent surgical procedures were included, of whom 44 974 patients (1.9%) were diagnosed with a PND. Among all patients, most were White (2 142 157 patients [90.0%]), presenting for orthopedic surgery (1 523 782 patients [64.0%]) in urban medical centers (2 179 893 patients [91.6%]) that were private nonprofits (1 798 749 patients [75.6%]). Patients with a PND, compared with those without a PND, experienced a significantly longer hospital length of stay (mean [SD], 5.91 [6.01] days vs 4.29 [4.18] days; P < .001), were less likely to be discharged home (9947 patients [22.1%] vs 914 925 patients [39.2%]; P < .001), and had a higher incidence of mortality at 1 year after treatment (4580 patients [10.2%] vs 103 767 patients [4.4%]; P < .001). After adjusting for patient and hospital characteristics, the presence of a PND within 1 year of the index procedure was associated with an increase of $17 275 (95% CI, $17 058-$17 491) in cost in the 1-year postadmission period (P < .001).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that among older Medicare patients undergoing surgical treatment, a diagnosis of a PND was associated with an increase in health care costs for up to 1 year following the surgical procedure. Given the magnitude of this cost burden, PNDs represent an appealing target for risk mitigation and improvement in value-based health care.

Frailty in Critical Care Medicine: A Review

Traditional approaches to clinical risk assessment utilize age as a marker of increased vulnerability to stress. Relatively recent advancements in the study of aging have led to the concept of the frailty syndrome, which represents a multidimensional state of depleted physiologic and psychosocial reserve and clinical vulnerability that is related to but variably present with advancing age. The frailty syndrome is now a well-established clinical entity that serves as both a guide for clinical intervention and a predictor of poor outcomes in the primary and acute care settings. The biological aspects of the syndrome broadly represent a network of interrelated perturbations involving the age-related accumulation of molecular, cellular, and tissue damage that leads to multisystem dysregulation, functional decline, and disproportionately poor response to physiologic stress. Given the complexity of the underlying biologic processes, several well-validated approaches to define frailty clinically have been developed, each with distinct and reasonable considerations. Stemming from this background, the past several years have seen a number of observational studies conducted in intensive care units that have established that the determination of frailty is both feasible and prognostically useful in the critical care setting. Specifically, frailty as determined by several different frailty measurement tools appears associated with mortality, increased health care utilization, and disability, and has the potential to improve risk stratification of intensive care patients. While substantial variability in the implementation of frailty measurement likely limits the generalizability of specific findings, the overall prognostic trends may offer some assistance in guiding management decisions with patients and their families. Although no trials have assessed interventions to improve the outcomes of critically ill older people living with frailty, the particular vulnerability of this population offers a promising target for intervention in the future.

Circulating Factors in Trauma Plasma Activate Specific Human Immune Cell Subsets

BACKGROUND

Trauma causes tissue injury that results in the release of damage associated molecular patterns (DAMPs) and other mediators at the site of injury and systemically. Such mediators disrupt immune system homeostasis and may activate multicellular immune responses with downstream complications such as the development of infections and sepsis. To characterize these alterations, we used time-of-flight mass cytometry to determine how trauma plasma affects normal peripheral blood mononuclear cell (PBMC) activation to gain insights into the kinetics and nature of trauma-induced circulating factors on human immune cell populations. A better understanding of the components that activate cells in trauma may aid in the discovery of therapeutic targets.

METHODS

PBMCs from healthy volunteers were cultured with 5% plasma (healthy, trauma-1day, or trauma-3day) or known DAMPs for 24 h. Samples were stained with a broad immunophenotyping CyTOF antibody panel. Multiplex (Luminex) cytokine assays were used to measure differences in multiple cytokine levels in healthy and trauma plasma samples.

RESULTS

Plasma from day 1, but not day 3 trauma patients induced the acute expansion of CD11c+ NK cells and CD73+/CCR7+ CD8 T cell subpopulations. Additionally, trauma plasma did not induce CD4+ T cell expansion but did cause a phenotypic shift towards CD38+/CCR7+ expressing CD4+ T cells. Multiplex analysis of cytokines by Luminex showed increased levels of IL-1RA, IL-6 and IL-15 in trauma-1day plasma. Similar to trauma day 1 plasma, PBMC stimulation with known DAMPs showed activation and expansion of CD11c+ NK cells.

CONCLUSIONS

We hypothesized that circulating factors in trauma plasma would induce phenotypic activation of normal human immune cell subsets. Using an unbiased approach, we identified specific changes in immune cell subsets that respond to trauma plasma. Additionally, CD11c+ NK cells expanded in response to DAMPs and LPS, suggesting they may also be responding to similar components in trauma plasma. Collectively, our data demonstrate that the normal PBMC response to trauma plasma involves marked changes in specific subsets of NK and CD8+ T cell populations. Future studies will target the function of these trauma plasma reactive immune cell subsets. These findings have important implications for the field of acute traumatic injuries.

Prevention of Early Postoperative Decline: A Randomized, Controlled Feasibility Trial of Perioperative Cognitive Training

BACKGROUND

Postoperative delirium and postoperative cognitive dysfunction (POCD) are common after cardiac surgery and contribute to an increased risk of postoperative complications, longer length of stay, and increased hospital mortality. Cognitive training (CT) may be able to durably improve cognitive reserve in areas deficient in delirium and POCD and, therefore, may potentially reduce the risk of these conditions. We sought to determine the feasibility and potential efficacy of a perioperative CT program to reduce the incidence of postoperative delirium and POCD in older cardiac surgery patients.

METHODS

Randomized controlled trial at a single tertiary care center. Participants included 45 older adults age 60-90 undergoing cardiac surgery at least 10 days from enrollment. Participants were randomly assigned in a 1:1 fashion to either perioperative CT via a mobile device or a usual care control. The primary outcome of feasibility was evaluated by enrollment patterns and adherence to protocol. Secondary outcomes of postoperative delirium and POCD were assessed using the Confusion Assessment Method and the Montreal Cognitive Assessment, respectively. Patient satisfaction was assessed via a postoperative survey.

RESULTS

Sixty-five percent of eligible patients were enrolled. Median (interquartile range [IQR]) adherence (as a percentage of prescribed minutes played) was 39% (20%-68%), 6% (0%-37%), and 19% (0%-56%) for the preoperative, immediate postoperative, and postdischarge periods, respectively. Median (IQR) training times were 245 (136-536), 18 (0-40), and 122 (0-281) minutes for each period, respectively. The incidence of postoperative delirium (CT group 5/20 [25%] versus control 3/20 [15%]; P = .69) and POCD (CT group 53% versus control 37%; P = .33) was not significantly different between groups for either outcome in this limited sample. CT participants reported a high level of agreement (on a scale of 0-100) with statements that the program was easy to use (median [IQR], 87 [75-97]) and enjoyable (85 [79-91]). CT participants agreed significantly more than controls that their memory (median [IQR], 75 [54-82] vs 51 [49-54]; P = .01) and thinking ability (median [IQR], 78 [64-83] vs 50 [41-68]; P = .01) improved as a result of their participation in the study.

CONCLUSIONS

A CT program designed for use in the preoperative period is an attractive target for future investigations of cognitive prehabilitation in older cardiac surgery patients. Changes in the functionality of the program and enrichment techniques may improve adherence in future trials. Further investigation is necessary to determine the potential efficacy of cognitive prehabilitation to reduce the risk of postoperative delirium and POCD.

The Year in Cardiothoracic and Vascular Anesthesia: Selected Highlights from 2019

This highlights in our specialty for 2019 begin with the ongoing major developments in transcatheter valve interventions. Thereafter, the advances in left ventricular assist devices are reviewed. The recent focus on conduit selection and robotic options in coronary artery bypass surgery are then explored. Finally, this special articles closes with a discussion of pulmonary hypertension in noncardiac surgery, anesthetic technique in cardiac surgery, as well as postoperative pneumonia and its outcome consequences.

HO-1 and CD39: It Takes Two to Protect the Realm

Cellular protective mechanisms exist to ensure survival of the cells and are a fundamental feature of all cells that is necessary for adapting to changes in the environment. Indeed, evolution has ensured that each cell is equipped with multiple overlapping families of genes that safeguard against pathogens, injury, stress, and dysfunctional metabolic processes. Two of the better-known enzymatic systems, conserved through all species, include the heme oxygenases (HO-1/HO-2), and the ectonucleotidases (CD39/73). Each of these systems generates critical bioactive products that regulate the cellular response to a stressor. Absence of these molecules results in the cell being extremely predisposed to collapse and, in most cases, results in the death of the cell. Recent reports have begun to link these two metabolic pathways, and what were once exclusively stand-alone are now being found to be intimately interrelated and do so through their innate ability to generate bioactive products including adenosine, carbon monoxide, and bilirubin. These simple small molecules elicit profound cellular physiologic responses that impact a number of innate immune responses, and participate in the regulation of inflammation and tissue repair. Collectively these enzymes are linked not only because of the mitochondria being the source of their substrates, but perhaps more importantly, because of the impact of their products on specific cellular responses. This review will provide a synopsis of the current state of the field regarding how these systems are linked and how they are now being leveraged as therapeutic modalities in the clinic.

The development and validation of the Score for the Prediction of Postoperative Respiratory Complications (SPORC-2) to predict the requirement for early postoperative tracheal re-intubation: a hospital registry study

Postoperative pulmonary complications are associated with an increase in mortality, morbidity and healthcare utilisation. The Agency for Healthcare Research and Quality recommends risk assessment for postoperative respiratory complications in patients undergoing surgery. In this hospital registry study of adult patients undergoing non-cardiac surgery between 2005 and 2017 at two independent healthcare networks, a prediction instrument for early postoperative tracheal re-intubation was developed and externally validated. This was based on the development of the Score for Prediction Of Postoperative Respiratory Complications. For predictor selection, stepwise backward logistic regression and bootstrap resampling were applied. Development and validation cohorts were represented by 90,893 patients at Partners Healthcare and 67,046 patients at Beth Israel Deaconess Medical Center, of whom 699 (0.8%) and 587 (0.9%) patients, respectively, had their tracheas re-intubated. In addition to five pre-operative predictors identified in the Score for Prediction Of Postoperative Respiratory Complications, the final model included seven additional intra-operative predictors: early post-tracheal intubation desaturation; prolonged duration of surgery; high fraction of inspired oxygen; high vasopressor dose; blood transfusion; the absence of volatile anaesthetic use; and the absence of lung-protective ventilation. The area under the receiver operating characteristic curve for the new score was significantly greater than that of the original Score for Prediction Of Postoperative Respiratory Complications (0.84 [95%CI 0.82-0.85] vs. 0.76 [95%CI 0.75-0.78], respectively; p < 0.001). This may allow clinicians to develop and implement strategies to decrease the risk of early postoperative tracheal re-intubation.