ORIGINAL RESEARCH Index to Predict In-hospital Mortality in Older Adults after Non-traumatic Emergency Department Intubations Kei Ouchi, MD, MPH*†‡ *Brigham and Women’s Hospital, Department of Emergency Medicine, Boston, Samuel Hohmann, PhD§¶ Massachusetts Tadahiro Goto, MD, MPH|| †Harvard Medical School, Department of Emergency Medicine, Boston, Massachusetts Peter Ueda, MD, PhD# ‡Ariadne Labs, Serious Illness Care Program, Boston, Massachusetts Emily L. Aaronson, MD|| §Vizient, Center for Advanced Analytics, Irving, Texas Daniel J. Pallin, MD, MPH*† ¶Rush University, Department of Health Systems Management, Chicago, Illinois Marcia A. Testa, PhD, MPH#** ||Massachusetts General Hospital, Department of Emergency Medicine, Boston, James A. Tulsky, MD††‡‡ Massachusetts Jeremiah D. Schuur, MD, MHS*† #Harvard T.H. Chan School of Public Health, Department of Global Health and Mara A. Schonberg, MD, MPH§§ Population, Boston, Massachusetts **Harvard T.H. Chan School of Public Health, Department of Biostatistics, Boston, Massachusetts ††Dana-Farber Cancer Institute, Department of Psychosocial Oncology and Palliative Care, Boston, Massachusetts ‡‡Brigham and Women’s Hospital, Department of Medicine, Division of Palliative Medicine, Boston, Massachusetts §§Beth Israel Deaconess Medical Center, Department of Medicine, Boston, Massachusetts Section Editor: Kathleen Walsh, DO, MS Submission history: Submitted December 14, 2016; Revision received February 10, 2017; Accepted February 15, 2017 Electronically published April 19, 2017 Full text available through open access at http://escholarship.org/uc/uciem_westjem DOI: 10.5811/westjem.2017.2.33325 Introduction: Our goal was to develop and validate an index to predict in-hospital mortality in older adults after non-traumatic emergency department (ED) intubations. Methods: We used Vizient administrative data from hospitalizations of 22,374 adults >75 years who underwent non-traumatic ED intubation from 2008-2015 at nearly 300 U.S. hospitals to develop and validate an index to predict in-hospital mortality. We randomly selected one half of participants for the development cohort and one half for the validation cohort. Considering 25 potential predictors, we developed a multivariable logistic regression model using least absolute shrinkage and selection operator method to determine factors associated with in-hospital mortality. We calculated risk scores using points derived from the final model’s beta coefficients. To evaluate calibration and discrimination of the final model, we used Hosmer-Lemeshow chi-square test and receiver-operating characteristic analysis and compared mortality by risk groups in the development and validation cohorts. Results: Death during the index hospitalization occurred in 40% of cases. The final model included six variables: history of myocardial infarction, history of cerebrovascular disease, history of metastatic cancer, age, admission diagnosis of sepsis, and admission diagnosis of stroke/ intracranial hemorrhage. Those with low-risk scores (<6) had 31% risk of in-hospital mortality while those with high-risk scores (>10) had 58% risk of in-hospital mortality. The Hosmer-Lemeshow chi-square of the model was 6.47 (p=0.09), and the c-statistic was 0.62 in the validation cohort. Conclusion: The model may be useful in identifying older adults at high risk of death after ED intubation. [West J Emerg Med. 2017;18(4)690-697.] Western Journal of Emergency Medicine 690 Volume 18, no. 4: June 2017 Ouchi et al. Index to Predict Mortality in Older Adults after Non-traumatic ED Intubations INTRODUCTION The vast majority (75%) of older adults with serious illness Population Health Research Capsule visit the emergency department (ED) in the last six months of their lives.1 Many of these patients often prioritize the quality of What do we already know about this issue? their life and quality of dying over simply living as long as Emergency physicians (EP) intuitively possible and fear health states worse than death.2,3 However, a understand the potential harm of ED recent systematic review revealed that the majority (56%-99%) of intubation for older adults, but we are unable older adults in the ED do not have advance directives available at to accurately predict the in-hospital mortality the time of ED presentation.4 Even if advance care planning for shared decision-making. occurred before ED arrival, it is rarely recorded in the medical record,5 and patients’ values and goals may change based on What was the research question? changing health states necessitating emergency physicians (EP) Can we develop an index to risk stratify to revisit patients’ goals.6 older adults for short-term mortality with the EPs often face much uncertainty about the potential benefit information available before intubation? of advanced medical interventions in patients near the end of their lives.7 During the brief and time-pressured ED encounter, What was the major finding of the study? it is often difficult to discern which treatments are not We developed an index to risk stratify older beneficial, especially for seriously ill older adults.8,9 EPs wish to adults that correctly sorts those who die from provide value-concordant care10 but do not feel adequately those who lived 62% of the time. trained to discuss goals of care with patients,11 especially when prognosis is uncertain.12 How does this improve population health? Endotracheal intubation, often performed in this population, EPs can use this information to paint the was designed to sustain life for patients in acute, reversible picture of potential harm of ED intubation for respiratory failure.13 However, large proportions of seriously ill older adults to aid in the shared decision- older adults suffer poor outcomes such as death on a ventilator or making process. chronic severe debility.14-16 Patients and caregivers providing consent in the acute setting are not well informed about the potential harm of this procedure and subsequent critical care since EPs themselves do not possess accurate prognostic information at the time of intubation. Patient-oriented decision aids have been used in the ED for a variety of conditions to facilitate shared decision-making with patients,17 yet none is available to help consortium of more than 117 principal members (academic older adults near the end of life decide whether or not to be medical centers) and more than 300 affiliate hospitals across the intubated or continue mechanical ventilation that was initiated United States, representing 95% of the nation’s non-profit prior to ED arrival. academic medical centers. Nearly 300 of these hospitals We sought to understand factors associated with in-hospital participate in the CDB/RM™, comprised of patient-level mortality of older adults receiving non-traumatic ED intubation. administrative data. The mission of Vizient is to allow Our objective was to create an index to predict in-hospital participating institutions to use the consortium data to accelerate mortality in older adults intubated in the ED for indications other organizational clinical performance.18 Data include patient than trauma. By creating an index to predict in-hospital mortality, demographics (age, sex, race, ethnicity), type of admission we hope to provide EPs with the necessary prognostic (elective, urgent, or emergent), procedure codes, diagnosis information to conduct a high quality, shared decision-making codes, length of stay and in-hospital mortality. Participating discussion with patients and/or their caregivers about whether or institutions submit all patient data monthly, and Vizient reviews not to undergo ED intubation or continue mechanical ventilation each data submission for quality. Diagnoses were coded using that was already started prior to ED arrival. the International Classification of Diseases, Ninth Revision, Clinical Modifications (ICD-9-CM).19 There is no funding METHODS source or sponsors in this study. Our institutional review board. Study Design and Setting approved this study. This is a retrospective cohort study using patient-level administrative data from Vizient Clinical Data Base/Resource Cohort Selection Manager™ (CDB/RM™). We obtained de-identified data We included adults aged ≥75 years who underwent ED regarding hospitalization after ED intubations. Vizient (formerly intubation at a CDB/RM™ participating site and had a known as the University HealthSystem Consortium) is a subsequent ED-originated hospital admission between Volume 18, no. 4: June 2017 691 Western Journal of Emergency Medicine Index to Predict Mortality in Older Adults after Non-traumatic ED Intubations Ouchi et al. January 1, 2008, and December 31, 2015. We excluded clinical judgment (e.g., combining chronic bronchitis and older adults with trauma as their admission diagnosis and symptoms involving respiratory system). Admission diagnoses those with out-of-hospital cardiac arrest or intubation. are typically determined by the clinician’s best assessment at the time of admission and may not be the final diagnoses of Study Sample the hospitalization. We chose to include them despite this We identified 22,374 individual patient records from CDB/ limitation because some are clinically highly correlated to RM™ that met our study criteria. We used Stata’s runiform such patients’ mortality (e.g., devastating CVA), and even if command to randomly select one half of the records to be in the our index could not be used prior to intubation such development cohort (n=10,789). We tested the reproducibility