An all-inclusive model for predicting invasive bacterial infection in febrile infants age 7-60 days.

BACKGROUND: Invasive bacterial infections (IBIs) in febrile infants are rare but potentially devastating. We aimed to derive and validate a predictive model for IBI among febrile infants age 7-60 days. METHODS: Data were abstracted retrospectively from electronic records of 37 emergency departments (EDs) for infants with a measured temperature >=100.4 F who underwent an ED evaluation with blood and urine cultures. Models to predict IBI were developed and validated respectively using a random 80/20 dataset split, including 10-fold cross-validation. We used precision recall curves as the classification metric. RESULTS: Of 4411 eligible infants with a mean age of 37 days, 29% had characteristics that would likely have excluded them from existing risk stratification protocols. There were 196 patients with IBI (4.4%), including 43 (1.0%) with bacterial meningitis. Analytic approaches varied in performance characteristics (precision recall range 0.04-0.29, area under the curve range 0.5-0.84), with the XGBoost model demonstrating the best performance (0.29, 0.84). The five most important variables were serum white blood count, maximum temperature, absolute neutrophil count, absolute band count, and age in days. CONCLUSION: A machine learning model (XGBoost) demonstrated the best performance in predicting a rare outcome among febrile infants, including those excluded from existing algorithms. IMPACT: Several models for the risk stratification of febrile infants have been developed. There is a need for a preferred comprehensive model free from limitations and algorithm exclusions that accurately predicts IBIs. This is the first study to derive an all-inclusive predictive model for febrile infants aged 7-60 days in a community ED sample with IBI as a primary outcome. This machine learning model demonstrates potential for clinical utility in predicting IBI.

Automated analysis of unstructured clinical assessments improves emergency department triage performance: A retrospective deep learning analysis.

Objectives: Efficient and accurate emergency department (ED) triage is critical to prioritize the sickest patients and manage department flow. We explored the use of electronic health record data and advanced predictive analytics to improve triage performance. Methods: Using a data set of over 5 million ED encounters of patients 18 years and older across 21 EDs from 2016 to 2020, we derived triage models using deep learning to predict 2 outcomes: hospitalization (primary outcome) and fast-track eligibility (exploratory outcome), defined as ED discharge with <2 resource types used (eg, laboratory or imaging studies) and no critical events (eg, resuscitative medications use or intensive care unit [ICU] admission). We report area under the receiver operator characteristic curve (AUC) and 95% confidence intervals (CI) for models using (1) triage variables alone (demographics and vital signs), (2) triage nurse clinical assessment alone (unstructured notes), and (3) triage variables plus clinical assessment for each prediction target. Results: We found 12.7% of patients were hospitalized (n = 673,659) and 37.0% were fast-track eligible (n = 1,966,615). The AUC was lowest for models using triage variables alone: AUC 0.77 (95% CI 0.77-0.78) and 0.70 (95% CI 0.70-0.71) for hospitalization and fast-track eligibility, respectively, and highest for models incorporating clinical assessment with triage variables for both hospitalization and fast-track eligibility: AUC 0.87 (95% CI 0.87-0.87) for both prediction targets. Conclusion: Our findings highlight the potential to use advanced predictive analytics to accurately predict key ED triage outcomes. Predictive accuracy was optimized when clinical assessments were added to models using simple structured variables alone.

Clinical decision support to Optimize Care of patients with Atrial Fibrillation or flutter in the Emergency department: protocol of a stepped-wedge cluster randomized pragmatic trial (O'CAFÉ trial).

BACKGROUND: Management of adults with atrial fibrillation (AF) or atrial flutter in the emergency department (ED) includes rate reduction, cardioversion, and stroke prevention. Different approaches to these components of care may lead to variation in frequency of hospitalization and stroke prevention actions, with significant implications for patient experience, cost of care, and risk of complications. Standardization using evidence-based recommendations could reduce variation in management, preventable hospitalizations, and stroke risk. METHODS: We describe the rationale for our ED-based AF treatment recommendations. We also describe the development of an electronic clinical decision support system (CDSS) to deliver these recommendations to emergency physicians at the point of care. We implemented the CDSS at three pilot sites to assess feasibility and solicit user feedback. We will evaluate the impact of the CDSS on hospitalization and stroke prevention actions using a stepped-wedge cluster randomized pragmatic clinical trial across 13 community EDs in Northern California. DISCUSSION: We hypothesize that the CDSS intervention will reduce hospitalization of adults with isolated AF or atrial flutter presenting to the ED and increase anticoagulation prescription in eligible patients at the time of ED discharge and within 30 days. If our hypotheses are confirmed, the treatment protocol and CDSS could be recommended to other EDs to improve management of adults with AF or atrial flutter. TRIAL REGISTRATION: ClinicalTrials.gov NCT05009225 .  Registered on 17 August 2021.

Evaluation of the Emergency Severity Index in US Emergency Departments for the Rate of Mistriage.

Importance: Accurate emergency department (ED) triage is essential to prioritize the most critically ill patients and distribute resources appropriately. The most used triage system in the US is the Emergency Severity Index (ESI). Objectives: To derive and validate an algorithm to assess the rate of mistriage and to identify characteristics associated with mistriage. Design, Setting, and Participants: This retrospective cohort study created operational definitions for each ESI level that use ED visit electronic health record data to classify encounters as undertriaged, overtriaged, or correctly triaged. These definitions were applied to a retrospective cohort to assess variation in triage accuracy by facility and patient characteristics in 21 EDs within the Kaiser Permanente Northern California (KPNC) health care system. All ED encounters by patients 18 years and older between January 1, 2016, and December 31, 2020, were assessed for eligibility. Encounters with missing ESI or incomplete ED time variables and patients who left against medical advice or without being seen were excluded. Data were analyzed between January 1, 2021, and November 30, 2022. Exposures: Assigned ESI level. Main Outcomes and Measures: Rate of undertriage and overtriage by assigned ESI level based on a mistriage algorithm and patient and visit characteristics associated with undertriage and overtriage. Results: A total of 5 315 176 ED encounters were included. The mean (SD) patient age was 52 (21) years; 44.3% of patients were men and 55.7% were women. In terms of race and ethnicity, 11.1% of participants were Asian, 15.1% were Black, 21.4% were Hispanic, 44.0% were non-Hispanic White, and 8.5% were of other (includes American Indian or Alaska Native, Native Hawaiian or other Pacific Islander, and multiple races or ethnicities), unknown, or missing race or ethnicity. Mistriage occurred in 1 713 260 encounters (32.2%), of which 176 131 (3.3%) were undertriaged and 1 537 129 (28.9%) were overtriaged. The sensitivity of ESI to identify a patient with high-acuity illness (correctly assigning ESI I or II among patients who had a life-stabilizing intervention) was 65.9%. In adjusted analyses, Black patients had a 4.6% (95% CI, 4.3%-4.9%) greater relative risk of overtriage and an 18.5% (95% CI, 16.9%-20.0%) greater relative risk of undertriage compared with White patients, while Black male patients had a 9.9% (95% CI, 9.8%-10.0%) greater relative risk of overtriage and a 41.0% (95% CI, 40.0%-41.9%) greater relative risk of undertriage compared with White female patients. High relative risk of undertriage was found among patients taking high-risk medications (30.3% [95% CI, 28.3%-32.4%]) and those with a greater comorbidity burden (22.4% [95% CI, 20.1%-24.4%]) and recent intensive care unit utilization (36.7% [95% CI, 30.5%-41.4%]). Conclusions and Relevance: In this retrospective cohort study of over 5 million ED encounters, mistriage with ESI was common. Quality improvement should focus on limiting critical undertriage, optimizing resource allocation by patient need, and promoting equity.

Patient and Visit Characteristics Associated With Physical Restraint Use in the Emergency Department.

Objective Physical restraints are used in emergency departments (EDs) to address behavioral emergencies in situations in which less restrictive methods have failed. The objective of this study was to evaluate for associations between patient/visit characteristics and physical restraint use. Study Design This study was designed as a cross-sectional, retrospective study of all encounters at Kaiser Permanente Northern California EDs from January 1, 2016, to December 31, 2019, to evaluate differences in patient and visit characteristics between visits involving physical restraint use and those without. Methods Using electronic health record data, this study identified physical restraint use among ED encounters and extracted demographic, clinical, and facility characteristics. The authors calculated odds ratios for physical restraint placement, adjusting for patient and visit characteristics and accounting for within-patient clustering. Results Among 4,410,816 encounters (representing 1,791,673 patients), 6369 encounters (0.1%) involved physical restraint use among 5,554 patients (0.3%). Variables associated with the lowest odds of physical restraint included female sex, presentation to the ED in more recent years, and presence of intentional self-harm/suicidal ideation. Variables associated with the highest odds of physical restraint included higher visit acuity and weekend presentations to the ED. Discussion This study, which leveraged a large, diverse patient sample generalizable to the Northern California population, found several patient and visit characteristics associated with physical restraint use in the ED. Conclusion Results of this study may help identify patient groups and situational factors that are most likely to lead to physical restraint use and structural factors contributing to disparities in care, thereby informing interventions to reduce physical restraint use when possible.

Higher intensity of 72-h noninvasive cardiac test referral does not improve short-term outcomes among emergency department patients with chest pain.

BACKGROUND: It is unclear whether referral for cardiac noninvasive testing (NIT) following emergency department (ED) chest pain encounters improves short-term outcomes. METHODS: This was a retrospective cohort study of patients presenting with chest pain, without ST-elevation myocardial infarction or myocardial injury by serum troponin testing, between 2013 and 2019 to 21 EDs within an integrated health care system. We examined the association between NIT referral (within 72 h of the ED encounter) and a primary outcome of 60-day major adverse cardiac events (MACE). Secondary outcomes were 60-day MACE without coronary revascularization (MACE-CR) and 60-day all-cause mortality. To account for confounding by indication for NIT, we grouped patient encounters into ranked tertiles of NIT referral intensity based on the likelihood of 72-h NIT referral associated with the initially assigned emergency physician, relative to local peers and within discrete time periods. Associations between NIT referral-intensity tertile and outcomes were assessed using risk-adjusted multivariable logistic regression. RESULTS: Among 210,948 eligible patient encounters, 72-h NIT referral frequency was 11.9%, 18.3%, and 25.9% in low, intermediate, and high NIT referral-intensity encounters, respectively. Compared with the low referral-intensity tertile, there was a higher risk of 60-day MACE within the high referral-intensity tertile (odds ratio [OR] = 1.11, 95% confidence interval [CI] = 1.04 to 1.17) due to more coronary revascularizations without corresponding differences in MACE-CR or all-cause mortality. In analyses stratified by patients' estimated risk (HEART score; 50.5% lower risk, 38.7% moderate risk, 10.8% higher risk), the difference in 60-day MACE was primarily attributable to moderate-risk encounters (OR = 1.15, 95% CI = 1.08 to 1.24), with no differences among either lower- (OR = 1.10, 95% CI = 0.92 to 1.31) or higher- (OR = 1.01, 95% CI = 0.90 to 1.14) risk encounters. CONCLUSION: Higher referral intensity for 72-h NIT was associated with higher risk of coronary revascularization but no difference in adverse events within 60 days. These findings further call into question the urgency of NIT among ED patients without objective evidence of myocardial injury.

Graded Coronary Risk Stratification for Emergency Department Patients With Chest Pain: A Controlled Cohort Study.

Background Resource utilization among emergency department (ED) patients with possible coronary chest pain is highly variable. Methods and Results Controlled cohort study amongst 21 EDs of an integrated healthcare system examining the implementation of a graded coronary risk stratification algorithm (RISTRA-ACS [risk stratification for acute coronary syndrome]). Thirteen EDs had access to RISTRA-ACS within the electronic health record (RISTRA sites) beginning in month 24 of a 48-month study period (January 2016 to December 2019); the remaining 8 EDs served as contemporaneous controls. Study participants had a chief complaint of chest pain and serum troponin measurement in the ED. The primary outcome was index visit resource utilization (observation unit or hospital admission, or 7-day objective cardiac testing). Secondary outcomes were 30-day objective cardiac testing, 60-day major adverse cardiac events (MACE), and 60-day MACE-CR (MACE excluding coronary revascularization). Difference-in-differences analyses controlled for secular trends with stratification by estimated risk and adjustment for risk factors, ED physician and facility. A total of 154 914 encounters were included. Relative to control sites, 30-day objective cardiac testing decreased at RISTRA sites among patients with low (≤2%) estimated 60-day MACE risk (-2.5%, 95% CI -3.7 to -1.2%, P<0.001) and increased among patients with non-low (>2%) estimated risk (+2.8%, 95% CI +0.6 to +4.9%, P=0.014), without significant overall change (-1.0%, 95% CI -2.1 to 0.1%, P=0.079). There were no statistically significant differences in index visit resource utilization, 60-day MACE or 60-day MACE-CR. Conclusions Implementation of RISTRA-ACS was associated with better allocation of 30-day objective cardiac testing and no change in index visit resource utilization or 60-day MACE. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03286179.

Clinical characteristics of COVID-19 patients evaluated in the emergency department: A retrospective cohort study of 801 cases.

BACKGROUND: Coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has extracted devastating tolls. Despite its pervasiveness, robust information on disease characteristics in the emergency department (ED) and how that information predicts clinical course remain limited. METHODS: We conducted a retrospective cohort study of the first ED visit from SARS-CoV-2-positive patients in our health system, from February 21, 2020 to April 5, 2020. We reviewed each patient's ED visit(s) and included the first visit with symptoms consistent with COVID-19. We collected demographic, clinical, and treatment variables from electronic health records and structured manual chart review. We used multivariable logistic regression to examine the association between patient characteristics and 2 primary outcomes: a critical outcome and hospitalization from index visit. Our critical outcome was defined as death or advanced respiratory support (high flow nasal cannula or greater) within 21 days. RESULTS: Of the first 1030 encounters, 801 met our inclusion criteria: 15% were over age 75 years, 47% were female, and 24% were non-Hispanic white. We found 161 (20%) had a critical outcome and 393 (49%) were hospitalized. Independent predictors of a critical outcome included a history of hypertension, abnormal chest x-ray, elevated neutrophil to lymphocyte ratio, elevated blood urea nitrogen (BUN), measured fever, and abnormal respiratory vital signs (respiratory rate, oxygen saturation). Independent predictors of hospitalization included abnormal pulmonary auscultation, elevated BUN, measured fever, and abnormal respiratory vital signs. CONCLUSIONS: In this large, diverse study of ED patients with COVID-19, we have identified numerous clinical characteristics that have independent associations with critical illness and hospitalization.

Prospective Validation and Comparative Analysis of Coronary Risk Stratification Strategies Among Emergency Department Patients With Chest Pain.

Background Coronary risk stratification is recommended for emergency department patients with chest pain. Many protocols are designed as "rule-out" binary classification strategies, while others use graded-risk stratification. The comparative performance of competing approaches at varying levels of risk tolerance has not been widely reported. Methods and Results This is a prospective cohort study of adult patients with chest pain presenting between January 2018 and December 2019 to 13 medical center emergency departments within an integrated healthcare delivery system. Using an electronic clinical decision support interface, we externally validated and assessed the net benefit (at varying risk thresholds) of several coronary risk scores (History, ECG, Age, Risk Factors, and Troponin [HEART] score, HEART pathway, Emergency Department Assessment of Chest Pain Score Accelerated Diagnostic Protocol), troponin-only strategies (fourth-generation assay), unstructured physician gestalt, and a novel risk algorithm (RISTRA-ACS). The primary outcome was 60-day major adverse cardiac event defined as myocardial infarction, cardiac arrest, cardiogenic shock, coronary revascularization, or all-cause mortality. There were 13 192 patient encounters included with a 60-day major adverse cardiac event incidence of 3.7%. RISTRA-ACS and HEART pathway had the lowest negative likelihood ratios (0.06, 95% CI, 0.03-0.10 and 0.07, 95% CI, 0.04-0.11, respectively) and the greatest net benefit across a range of low-risk thresholds. RISTRA-ACS demonstrated the highest discrimination for 60-day major adverse cardiac event (area under the receiver operating characteristic curve 0.92, 95% CI, 0.91-0.94, P<0.0001). Conclusions RISTRA-ACS and HEART pathway were the optimal rule-out approaches, while RISTRA-ACS was the best-performing graded-risk approach. RISTRA-ACS offers promise as a versatile single approach to emergency department coronary risk stratification. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03286179.

Effect of Clinical Decision Support on Diagnostic Imaging for Pediatric Appendicitis: A Cluster Randomized Trial.

Importance: Appendicitis is the most common pediatric surgical emergency. Efforts to improve efficiency and quality of care have increased reliance on computed tomography (CT) and ultrasonography (US) in children with suspected appendicitis. Objective: To evaluate the effectiveness of an electronic health record-linked clinical decision support intervention, AppyCDS, on diagnostic imaging, health care costs, and safety outcomes for patients with suspected appendicitis. Design, Setting, and Participants: In this parallel, cluster randomized trial, 17 community-based general emergency departments (EDs) in California, Minnesota, and Wisconsin were randomized to the AppyCDS intervention group or usual care (UC) group. Patients were aged 5 to 20 years, presenting for an ED visit with right-sided or diffuse abdominal pain lasting 5 days or less. We excluded pregnant patients, those with a prior appendectomy, those with selected comorbidities, and those with traumatic injuries. The trial was conducted from October 2016 to July 2019. Interventions: AppyCDS prompted data entry at the point of care to estimate appendicitis risk using the pediatric appendicitis risk calculator (pARC). Based on pARC estimates, AppyCDS recommended next steps in care. Main Outcomes and Measures: Primary outcomes were CT, US, or any imaging (CT or US) during the index ED visit. Safety outcomes were perforations, negative appendectomies, and missed appendicitis. Costs were a secondary outcome. Ratio of ratios (RORs) for primary and safety outcomes and differences by group in cost were used to evaluate effectiveness of the clinical decision support tool. Results: We enrolled 3161 patients at intervention EDs and 2779 patients at UC EDs. The mean age of patients was 11.9 (4.6) years and 2614 (44.0%) were boys or young men. RORs for CT (0.94; 95% CI, 0.75-1.19), US (0.98; 95% CI, 0.84-1.14), and any imaging (0.96; 95% CI, 0.86-1.07) did not differ by study group. In an exploratory analysis conducted in 1 health system, AppyCDS was associated with a reduction in any imaging (ROR, 0.82; 95% CI, 0.73- 0.93) for patients with pARC score of 15% or less and a reduction in CT (ROR, 0.58; 95% CI, 0.45-0.74) for patients with a pARC score of 16% to 50%. Perforations, negative appendectomies, and cases of missed appendicitis by study phase did not differ significantly by study group. Costs did not differ overall by study group. Conclusions and Relevance: In this study, AppyCDS was not associated with overall reductions in diagnostic imaging; exploratory analysis revealed more appropriate use of imaging in patients with a low pARC score. Trial Registration: ClinicalTrials.gov Identifier: NCT02633735.

Automated Retrospective Calculation of the EDACS and HEART Scores in a Multicenter Prospective Cohort of Emergency Department Chest Pain Patients.

OBJECTIVES: Coronary risk scores are commonly applied to emergency department patients with undifferentiated chest pain. Two prominent risk score-based protocols are the Emergency Department Assessment of Chest pain Score Accelerated Diagnostic Protocol (EDACS-ADP) and the History, ECG, Age, Risk factors, and Troponin (HEART) pathway. Since prospective documentation of these risk determinations can be challenging to obtain, quality improvement projects could benefit from automated retrospective risk score classification methodologies. METHODS: EDACS-ADP and HEART pathway data elements were prospectively collected using a Web-based electronic clinical decision support (eCDS) tool over a 24-month period (2018-2019) among patients presenting with chest pain to 13 EDs within an integrated health system. Data elements were also extracted and processed electronically (retrospectively) from the electronic health record (EHR) for the same patients. The primary outcome was agreement between the prospective/eCDS and retrospective/EHR data sets on dichotomous risk protocol classification, as assessed by kappa statistics (ĸ). RESULTS: There were 12,110 eligible eCDS uses during the study period, of which 66 and 47% were low-risk encounters by EDACS-ADP and HEART pathway, respectively. Agreement on low-risk status was acceptable for EDACS-ADP (ĸ = 0.73, 95% confidence interval [CI] = 0.72 to 0.75) and HEART pathway (ĸ = 0.69, 95% CI = 0.68 to 0.70) and for the continuous scores (interclass correlation coefficients = 0.87 and 0.84 for EDACS and HEART, respectively). CONCLUSIONS: Automated retrospective determination of low risk status by either the EDACS-ADP or the HEART pathway provides acceptable agreement compared to prospective score calculations, providing a feasible risk adjustment option for use in large data set analyses.

Diagnostic Performance of Emergency Physician Gestalt for Predicting Acute Appendicitis in Patients Age 5 to 20 Years.

OBJECTIVES: Pediatric appendicitis remains a challenging diagnosis in the emergency department (ED). Available risk prediction algorithms may contribute to excessive ED imaging studies. Incorporation of physician gestalt assessment could help refine predictive tools and improve diagnostic imaging decisions. METHODS: This study was a subanalysis of a parent study that prospectively enrolled patients ages 5 to 20.9 years with a chief complaint of abdominal pain presenting to 11 community EDs within an integrated delivery system between October 1, 2016, and September 30, 2018. Prior to diagnostic imaging, attending emergency physicians enrolled patients with ≤5 days of right-sided or diffuse abdominal pain using a Web-based application embedded in the electronic health record. Predicted risk (gestalt) of acute appendicitis was prospectively entered using a sliding scale from 1% to 100%. As a planned secondary analysis, we assessed the performance of gestalt via c-statistics of receiver operating characteristic (ROC) curves; tested associations between gestalt performance and patient, physician, and facility characteristics; and examined clinical characteristics affecting gestalt estimates. RESULTS: Of 3,426 patients, 334 (9.8%) had confirmed appendicitis. Physician gestalt had excellent ROC curve characteristics (c-statistic = 0.83, 95% confidence interval = 0.81 to 0.85), performing particularly well in the low-risk strata (appendicitis rate = 1.1% in gestalt 1%-10% range, negative predictive value of 98.9% for appendicitis diagnosis). Physicians with ≥5 years since medical school graduation demonstrated improved gestalt performance over those with less experience (p = 0.007). All clinical characteristics tested, except pain <24 hours, were significantly associated with physician gestalt value (p < 0.05). CONCLUSION: Physician gestalt for acute appendicitis diagnosis performed well, especially in low-risk patients and when employed by experienced physicians.

Validation of the Pediatric Appendicitis Risk Calculator (pARC) in a Community Emergency Department Setting.

STUDY OBJECTIVE: The pediatric Appendicitis Risk Calculator (pARC) is a validated clinical tool for assessing a child's probability of appendicitis. Our objective was to assess the performance of the pARC in community emergency departments (EDs) and to compare its performance with that of the Pediatric Appendicitis Score (PAS). METHODS: We conducted a prospective validation study from October 1, 2016, to April 30, 2018, in 11 community EDs serving general populations. Patients aged 5 to 20.9 years and with a chief complaint of abdominal pain and less than or equal to 5 days of right-sided or diffuse abdominal pain were eligible for study enrollment. Our primary outcome was the presence or absence of appendicitis within 7 days of the index visit. We reported performance characteristics and secondary outcomes by pARC risk strata and compared the receiver operator characteristic (ROC) curves of the PAS and pARC. RESULTS: We enrolled 2,089 patients with a mean age of 12.4 years, 46% of whom were male patients. Appendicitis was confirmed in 353 patients (16.9%), of whom 55 (15.6%) had perforated appendixes. Fifty-four percent of patients had very low (<5%) or low (5% to 14%) predicted risk, 43% had intermediate risk (15% to 84%), and 4% had high risk (≥85%). In the very-low- and low-risk groups, 1.4% and 3.0% of patients had appendicitis, respectively. The area under the ROC curve was 0.89 (95% confidence interval 0.87 to 0.92) for the pARC compared with 0.80 (95% confidence interval 0.77 to 0.82) for the PAS. CONCLUSION: The pARC accurately assessed appendicitis risk for children aged 5 years and older in community EDs and the pARC outperformed the PAS.

Increasing Safe Outpatient Management of Emergency Department Patients With Pulmonary Embolism: A Controlled Pragmatic Trial.

Background: Many low-risk patients with acute pulmonary embolism (PE) in the emergency department (ED) are eligible for outpatient care but are hospitalized nonetheless. One impediment to home discharge is the difficulty of identifying which patients can safely forgo hospitalization. Objective: To evaluate the effect of an integrated electronic clinical decision support system (CDSS) to facilitate risk stratification and decision making at the site of care for patients with acute PE. Design: Controlled pragmatic trial. (ClinicalTrials.gov: NCT03601676). Setting: All 21 community EDs of an integrated health care delivery system (Kaiser Permanente Northern California). Patients: Adult ED patients with acute PE. Intervention: Ten intervention sites selected by convenience received a multidimensional technology and education intervention at month 9 of a 16-month study period (January 2014 to April 2015); the remaining 11 sites served as concurrent controls. Measurements: The primary outcome was discharge to home from either the ED or a short-term (<24-hour) outpatient observation unit based in the ED. Adverse outcomes included return visits for PE-related symptoms within 5 days and recurrent venous thromboembolism, major hemorrhage, and all-cause mortality within 30 days. A difference-in-differences approach was used to compare pre-post changes at intervention versus control sites, with adjustment for demographic and clinical characteristics. Results: Among 881 eligible patients diagnosed with PE at intervention sites and 822 at control sites, adjusted home discharge increased at intervention sites (17.4% pre- to 28.0% postintervention) without a concurrent increase at control sites (15.1% pre- and 14.5% postintervention). The difference-in-differences comparison was 11.3 percentage points (95% CI, 3.0 to 19.5 percentage points; P = 0.007). No increases were seen in 5-day return visits related to PE or in 30-day major adverse outcomes associated with CDSS implementation. Limitation: Lack of random allocation. Conclusion: Implementation and structured promotion of a CDSS to aid physicians in site-of-care decision making for ED patients with acute PE safely increased outpatient management. Primary Funding Source: Garfield Memorial National Research Fund and The Permanente Medical Group Delivery Science and Physician Researcher Programs.

Development and Validation of a Novel Pediatric Appendicitis Risk Calculator (pARC).

OBJECTIVES: We sought to develop and validate a clinical calculator that can be used to quantify risk for appendicitis on a continuous scale for patients with acute abdominal pain. METHODS: The pediatric appendicitis risk calculator (pARC) was developed and validated through secondary analyses of 3 distinct cohorts. The derivation sample included visits to 9 pediatric emergency departments between March 2009 and April 2010. The validation sample included visits to a single pediatric emergency department from 2003 to 2004 and 2013 to 2015. Variables evaluated were as follows: age, sex, temperature, nausea and/or vomiting, pain duration, pain location, pain with walking, pain migration, guarding, white blood cell count, and absolute neutrophil count. We used stepwise regression to develop and select the best model. Test performance of the pARC was compared with the Pediatric Appendicitis Score (PAS). RESULTS: The derivation sample included 2423 children, 40% of whom had appendicitis. The validation sample included 1426 children, 35% of whom had appendicitis. The final pARC model included the following variables: sex, age, duration of pain, guarding, pain migration, maximal tenderness in the right-lower quadrant, and absolute neutrophil count. In the validation sample, the pARC exhibited near perfect calibration and a high degree of discrimination (area under the curve: 0.85; 95% confidence interval: 0.83 to 0.87) and outperformed the PAS (area under the curve: 0.77; 95% confidence interval: 0.75 to 0.80). By using the pARC, almost half of patients in the validation cohort could be accurately classified as at <15% risk or ≥85% risk for appendicitis, whereas only 23% would be identified as having a comparable PAS of <3 or >8. CONCLUSIONS: In our validation cohort of patients with acute abdominal pain, the pARC accurately quantified risk for appendicitis.

Performance of Coronary Risk Scores Among Patients With Chest Pain in the Emergency Department.

BACKGROUND: Both the modified History, Electrocardiogram, Age, Risk factors and Troponin (HEART) score and the Emergency Department Assessment of Chest pain Score (EDACS) can identify patients with possible acute coronary syndrome (ACS) at low risk (<1%) for major adverse cardiac events (MACE). OBJECTIVES: The authors sought to assess the comparative accuracy of the EDACS (original and simplified) and modified HEART risk scores when using cardiac troponin I (cTnI) cutoffs below the 99th percentile, and obtain precise MACE risk estimates. METHODS: The authors conducted a retrospective study of adult emergency department (ED) patients evaluated for possible ACS in an integrated health care system between 2013 and 2015. Negative predictive values for MACE (composite of myocardial infarction, cardiogenic shock, cardiac arrest, and all-cause mortality) were determined at 60 days. Reclassification analyses were used to assess the comparative accuracy of risk scores and lower cTnI cutoffs. RESULTS: A total of 118,822 patients with possible ACS were included. The 3 risk scores' accuracies were optimized using the lower limit of cTnI quantitation (<0.02 ng/ml) to define low risk for 60-day MACE, with reclassification yields ranging between 3.4% and 3.9%, while maintaining similar negative predictive values (range 99.49% to 99.55%; p = 0.27). The original EDACS identified the largest proportion of patients as low risk (60.6%; p < 0.0001). CONCLUSIONS: Among ED patients with possible ACS, the modified HEART score, original EDACS, and simplified EDACS all predicted a low risk of 60-day MACE with improved accuracy using a cTnI cutoff below the 99th percentile. The original EDACS identified the most low-risk patients, and thus may be the preferred risk score.

Outpatient Management of Emergency Department Patients With Acute Pulmonary Embolism: Variation, Patient Characteristics, and Outcomes.

STUDY OBJECTIVE: Outpatient management of emergency department (ED) patients with acute pulmonary embolism is uncommon. We seek to evaluate the facility-level variation of outpatient pulmonary embolism management and to describe patient characteristics and outcomes associated with home discharge. METHODS: The Management of Acute Pulmonary Embolism (MAPLE) study is a retrospective cohort study of patients with acute pulmonary embolism undertaken in 21 community EDs from January 2013 to April 2015. We gathered demographic and clinical variables from comprehensive electronic health records and structured manual chart review. We used multivariable logistic regression to assess the association between patient characteristics and home discharge. We report ED length of stay, consultations, 5-day pulmonary embolism-related return visits and 30-day major hemorrhage, recurrent venous thromboembolism, and all-cause mortality. RESULTS: Of 2,387 patients, 179 were discharged home (7.5%). Home discharge varied significantly between EDs, from 0% to 14.3% (median 7.0%; interquartile range 4.2% to 10.9%). Median length of stay for home discharge patients (excluding those who arrived with a new pulmonary embolism diagnosis) was 6.0 hours (interquartile range 4.6 to 7.2 hours) and 81% received consultations. On adjusted analysis, ambulance arrival, abnormal vital signs, syncope or presyncope, deep venous thrombosis, elevated cardiac biomarker levels, and more proximal emboli were inversely associated with home discharge. Thirteen patients (7.2%) who were discharged home had a 5-day pulmonary embolism-related return visit. Thirty-day major hemorrhage and recurrent venous thromboembolism were uncommon and similar between patients hospitalized and those discharged home. All-cause 30-day mortality was lower in the home discharge group (1.1% versus 4.4%). CONCLUSION: Home discharge of ED patients with acute pulmonary embolism was uncommon and varied significantly between facilities. Patients selected for outpatient management had a low incidence of adverse outcomes.

Outcomes Following Possible Undiagnosed Aneurysmal Subarachnoid Hemorrhage: A Contemporary Analysis.

OBJECTIVES: Existing literature suggests that patients with aneurysmal subarachnoid hemorrhage (aSAH) and "sentinel" aSAH symptoms prompting healthcare evaluations prior to aSAH diagnosis are at increased risk of unfavorable neurologic outcomes and death. Accordingly, these encounters have been presumed to be unrecognized opportunities to diagnose aSAH and the worse outcomes representative of the added risks of delayed diagnoses. We sought to reinvestigate this paradigm among a contemporary cohort of patients with aSAH. METHODS: A case-control cohort was retrospectively assembled among patients diagnosed with aSAH between January 1, 2007 and June 30, 2013 within an integrated healthcare delivery system. Patients with a discrete clinical evaluation for headache or neck pain within 14 days prior to formal aSAH diagnosis were identified as cases, and the remaining patients served as controls. Modified Rankin Scale scores at 90 days and 1 year were determined by structured chart review. Multivariable logistic regression controlling for age, sex, ethnicity, presence of intracerebral or intraventricular hemorrhage at diagnosis, and aneurysm size was used to compare adjusted outcomes. Sensitivity analyses were performed using varying definitions of favorable neurologic outcomes, a restricted control subgroup of patients with normal mental status at hospital admission, inclusion of additional cases that were diagnosed outside of the integrated health system, and exclusion of patients without evidence of subarachnoid blood on initial noncontrast cranial computed tomography (CT) at the diagnostic encounter (i.e. "CT-negative" SAH). RESULTS: A total of 450 patients with aSAH were identified, 46 (10%) of whom had clinical evaluations for possible aSAH-related symptoms in the 14 days preceding formal diagnosis (cases). In contrast to prior reports, no differences were observed among cases compared to control patients in adjusted odds of death or unfavorable neurologic status at 90 days (0.35, 95% confidence interval [CI] = 0.11-1.15; 0.59, 95% CI = 0.22-1.60, respectively) or at 1 year (0.58, 95% CI = 0.19-1.73; 0.52, 95% CI = 0.18-1.51, respectively). Likewise, neither restricting the analysis to a control subgroup of patients with normal mental status at hospital admission, varying the dichotomous definition of unfavorable neurologic outcome, inclusion of cases diagnosed outside the integrated health system, or exclusion of patients with CT-negative SAH resulted in significant adjusted outcome differences. CONCLUSION: In a contemporary cohort of patients with aSAH, we observed no statistically significant increase in the adjusted odds of death or unfavorable neurologic outcomes among patients with clinical evaluations for possible aSAH-related symptoms in the 14 days preceding formal diagnosis of aSAH. While these findings cannot exclude a smaller risk difference than previously reported, they can help refine decision analyses and testing threshold determinations for patients with possible aSAH.

Risk stratifying emergency department patients with acute pulmonary embolism: Does the simplified Pulmonary Embolism Severity Index perform as well as the original?

INTRODUCTION: The Pulmonary Embolism Severity Index (PESI) is a validated prognostic score to estimate the 30-day mortality of emergency department (ED) patients with acute pulmonary embolism (PE). A simplified version (sPESI) was derived but has not been as well studied in the U.S. We sought to validate both indices in a community hospital setting in the U.S. and compare their performance in predicting 30-day all-cause mortality and classification of cases into low-risk and higher-risk categories. MATERIALS AND METHODS: This retrospective cohort study included adults with acute objectively confirmed PE from 1/2013 to 4/2015 across 21 community EDs. We evaluated the misclassification rate of the sPESI compared with the PESI. We assessed accuracy of both indices with regard to 30-day mortality. RESULTS: Among 3006 cases of acute PE, the 30-day all-cause mortality rate was 4.4%. The sPESI performed as well as the PESI in identifying low-risk patients: both had similar sensitivities, negative predictive values, and negative likelihood ratios. The sPESI, however, classified a smaller proportion of patients as low risk than the PESI (27.5% vs. 41.0%), but with similar low-risk mortality rates (<1%). Compared with the PESI, the sPESI overclassified 443 low-risk patients (14.7%) as higher risk, yet their 30-day mortality was 0.7%. The sPESI underclassified 100 higher-risk patients (3.3%) as low risk who also had a low mortality rate (1.0%). CONCLUSIONS: Both indices identified patients with PE who were at low risk for 30-day mortality. The sPESI, however, misclassified a significant number of low-mortality patients as higher risk, which could lead to unnecessary hospitalizations.