Factors associated with a high-risk return visit to the emergency department: a case-crossover study

Evaluation of a Structured Review Process for Emergency Department Return Visits with Admission

BACKGROUND

Review of emergency department (ED) revisits with admission allows the identification of improvement opportunities. Applying a health equity lens to revisits may highlight potential disparities in care transitions. Universal definitions or practicable frameworks for these assessments are lacking. The authors aimed to develop a structured methodology for this quality assurance (QA) process, with a layered equity analysis.

METHODS

The authors developed a classification instrument to identify potentially preventable 72-hour returns with admission (PPRA-72), accounting for directed, unrelated, unanticipated, or disease progression returns. A second review team assessed the instrument reliability. A self-reported race/ethnicity (R/E) and language algorithm was developed to minimize uncategorizable data. Disposition distribution, return rates, and PPRA-72 classifications were analyzed for disparities using Pearson chi-square and Fisher's exact tests.

RESULTS

The PPRA-72 rate was 4.8% for 2022 ED return visits requiring admission. Review teams achieved 93% agreement (κ = 0.51) for the binary determination of PPRA-72 vs. nonpreventable returns. There were significant differences between R/E and language in ED dispositions (p < 0.001), with more frequent admissions for the R/E White at the index visit and Other at the 72-hour return visit. Rates of return visits within 72 hours differed significantly by R/E (p < 0.001) but not by language (p = 0.156), with the R/E Black most frequent to have a 72-hour return. There were no differences between R/E (p = 0.446) or language (p = 0.248) in PPRA-72 rates. The initiative led to system improvements through informatics optimizations, triage protocols, provider feedback, and education.

CONCLUSION

The authors developed a review methodology for identifying improvement opportunities across ED 72-hour returns. This QA process enabled the identification of areas of disparity, with the continuous aim to develop next steps in ensuring health equity in care transitions.

Prediction of high-risk emergency department revisits from a machine-learning algorithm: a proof-of-concept study

BACKGROUND

High-risk emergency department (ED) revisit is considered an important quality indicator that may reflect an increase in complications and medical burden. However, because of its multidimensional and highly complex nature, this factor has not been comprehensively investigated. This study aimed to predict high-risk ED revisit with a machine-learning (ML) approach.

METHODS

This 3-year retrospective cohort study assessed adult patients between January 2019 and December 2021 from National Taiwan University Hospital Hsin-Chu Branch with high-risk ED revisit, defined as hospital or intensive care unit admission after ED return within 72 hours. A total of 150 features were preliminarily screened, and 79 were used in the prediction model. Deep learning, random forest, extreme gradient boosting (XGBoost) and stacked ensemble algorithm were used. The stacked ensemble model combined multiple ML models and performed model stacking as a meta-level algorithm. Confusion matrix, accuracy, sensitivity, specificity and area under the receiver operating characteristic curve (AUROC) were used to evaluate performance.

RESULTS

Analysis was performed for 6282 eligible adult patients: 5025 (80.0%) in the training set and 1257 (20.0%) in the testing set. High-risk ED revisit occurred for 971 (19.3%) of training set patients vs 252 (20.1%) in the testing set. Leading predictors of high-risk ED revisit were age, systolic blood pressure and heart rate. The stacked ensemble model showed more favourable prediction performance (AUROC 0.82) than the other models: deep learning (0.69), random forest (0.78) and XGBoost (0.79). Also, the stacked ensemble model achieved favourable accuracy and specificity.

CONCLUSION

The stacked ensemble algorithm exhibited better prediction performance in which the predictions were generated from different ML algorithms to optimally maximise the final set of results. Patients with older age and abnormal systolic blood pressure and heart rate at the index ED visit were vulnerable to high-risk ED revisit. Further studies should be conducted to externally validate the model.

The Predictive Role of Lactate in the Emergency Department in Patients with Severe Dyspnea

Objective

An accurate identification of patients at the need for prioritized diagnostics and care are crucial in the emergency department (ED). Blood gas (BG) analysis is a widely available laboratory test, which allows to measure vital parameters, including markers of ventilation and perfusion. The aim of our analysis was to assess whether blood gas parameters in patients with dyspnea at an increased risk of respiratory failure admitted to the ED can predict short-term outcomes.

Methods

The study group eventually consisted of 108 patients, with available BG analysis. The clinical and laboratory parameters were retrospectively evaluated, and three groups were distinguished-arterial blood gas (ABG), venous blood gas (VBG), and mixed blood gas. The primary endpoint was short-term, all-cause mortality during the follow-up of median (quartile 1-quartile 3) 2 (1-4) months. The independent risk factors for mortality that could be obtained from blood gas sampling were evaluated.

Results

The short-term mortality was 35.2% (38/108). Patients who died were more frequently initially assigned to the red triage risk group, more burdened with comorbidities, and the median SpO2 on admission was significantly lower than in patients who survived the follow-up period. In the multivariable analysis, lactate was the strongest independent predictor of death, with 1 mmol/L increasing all-cause mortality by 58% in ABG (95% CI: 1.01-2.47), by 80% in VBG (95% CI: 1.13-2.88), and by 68% in the mixed blood gas analysis (95% CI: 1.22-2.31), what remained significant in VBG and mixed group after correction for base excess. In each group, pH, pO2, and pCO2 did not predict short-term mortality.

Conclusions

In patients admitted to the ED due to dyspnea, at risk of respiratory failure, lactate levels in arterial, venous, and mixed blood samples are independent predictors of short-term mortality.

Association between independent practice time and patient outcomes in the emergency department: a retrospective study of residents in three urban hospitals in Taiwan

BACKGROUND

The purpose of the study was to investigate the relationship between the independent practice time of residents and the quality of care provided in the Emergency Department (ED) across three urban hospitals in Taiwan. The study focused on non-pediatric and non-obstetric complaints, aiming to provide insights into the optimal balance between resident autonomy and patient safety.

METHODS

A comprehensive retrospective study was conducted using de-identified electronic health records (EHRs) from the hospital's integrated medical database (iMD) from August 2015 to July 2019. The independent practice time was defined as the duration from the first medical order by a resident to the first modifications by the attending physician. The primary outcome was revisits to the ED within 72 h following discharge. Statistical analysis was conducted using RStudio and pyGAM.

RESULTS

The study identified several factors associated with shorter independent practice times (< 30 minutes), including older patient age, male sex, higher body temperature, higher heart rate, lower blood pressure, and the presence of certain comorbidities. Residents practicing independently for 30-120 minutes were associated with similar adjusted odds of patient revisits to the ED (OR 1.034, 95% CI 0.978-1.093) and no higher risk of 7-day mortality (OR 0.674, 95% CI 0.592-0.767) compared to the group with less autonomy. However, independent practice times exceeding 120 minutes were associated with higher odds of revisiting the ED within 72 h. For the group with 120-210 minutes of independent practice time, the OR was 1.113 (95% CI: 1.025-1.208, p = 0.011). For the group with > 210 minutes, the OR was 1.259 (95% CI: 1.094-1.449, p = 0.001), indicating an increased risk of adverse outcomes as the independent practice time increasing.

CONCLUSIONS

The study concludes that while providing residents an independent practice time between 30 to 120 minutes may be beneficial, caution should be exercised when this time exceeds 120 minutes. The findings underscore the importance of optimal supervision in enhancing patient care quality and safety. Further research is recommended to explore the long-term effects of different levels of resident autonomy on patient outcomes and the professional development of the residents themselves.

Differences in the characteristics and patterns of adult emergency department return visits before and after the coronavirus disease 2019 outbreak

BACKGROUND

Data about changes in the characteristics of ED return visits before and after the COVID-19 outbreak are limited. This study aimed to report the differences on utility in ED return visits after the COVID-19 outbreak.

METHODS

This retrospective cohort study was conducted from 2019 to 2020. Adult patients with ED return visits were included in the analysis. Variables including demographic characteristics, pre-comorbidities, triage levels, vital signs, chief complaints, management, and diagnosis were recorded and confirmed via a manual assessment.

RESULTS

The proportion of patients with ED visits decreased by 23%. Hence, that of patients with ED return visits also reduced from 2580 to 2020 patients (22%) after the COVID-19 outbreak. The average age (60-57.8 years) of patients with return visits was significantly younger, and the proportion of female patients decreased remarkably. Further, the proportion of patients with chronic pre-existing diseases at the return visit significantly differed after the COVID-19 outbreak. The proportion of patients with chief complaints including dizziness, dyspnea, cough, vomiting, diarrhea, and chills during the return visits significantly differed before and after the COVID-19 pandemic. In the multivariable logistic regression model, age, high triage level were significantly associated with unfavorable outcome return visit.

CONCLUSION

The use of services in the ED has changed since the COVID-19 outbreak. Hence, the proportion of patients with unplanned return visits within 72 h decreased. After the COVID-19 outbreak, people are now cautious whether they should return to the ED, as in the pre-pandemic situation, or just treat conservatively at home.

Predictors of 72-h unscheduled return visits with admission in patients presenting to the emergency department with abdominal pain

BACKGROUND

Unscheduled return visits (URVs) to the emergency department (ED) constitute a crucial indicator of patient care quality.

OBJECTIVE

We aimed to analyze the clinical characteristics of patients who visited the ED with abdominal pain and to identify the risk of URVs with admission (URVAs) from URVs without admission (URVNAs).

METHODS

This retrospective study included adult patients who visited the ED of Taipei Medical University Hospital because of abdominal pain and revisited in 72 h over a 5-year period (January 1, 2014, to December 31, 2018). Multivariable logistic regression analysis was employed to identify risk factors for URVAs and receiver operating characteristic (ROC) curve analysis was performed to determine the efficacy of variables predicting URVAs and the optimal cut-off points for the variables. In addition, a classification and regression tree (CART)-based scoring system was used for predicting risk of URVA.

RESULTS

Of 702 eligible patients with URVs related to abdominal pain, 249 had URVAs (35.5%). In multivariable analysis, risk factors for URVAs during the index visit included execution of laboratory tests (yes vs no: adjusted odds ratio [AOR], 4.32; 95% CI 2.99-6.23), older age (≥ 40 vs < 40 years: AOR, 2.10; 95% CI 1.10-1.34), Level 1-2 triage scores (Levels 1-2 vs Levels 3-5: AOR, 2.30; 95% CI 1.26-4.19), and use of ≥ 2 analgesics (≥ 2 vs < 2: AOR, 2.90; 95% CI 1.58-5.30). ROC curve analysis results revealed the combination of these 4 above variables resulted in acceptable performance (area under curve: 0.716). The above 4 variables were used in the CART model to evaluate URVA propensity.

CONCLUSIONS

Elder patients with abdominal pain who needed laboratory workup, had Level 1-2 triage scores, and received ≥ 2 doses of analgesics during their index visits to the ED had higher risk of URVAs.

Clinical factors predicting return emergency department visits in chemotherapy-induced febrile neutropenia patients

BACKGROUND

Although chemotherapy-induced febrile neutropenia (FN) is the most common and life-threatening oncologic emergency, the characteristics and outcomes associated with return visits to the emergency department (ED) in these patients are uncertain. Hence, we aimed to investigate the predictive factors and clinical outcomes of chemotherapy-induced FN patients returning to the ED.

METHOD

This single-center, retrospective observational study spanning 14 years included chemotherapy-induced FN patients who visited the ED and were discharged. The primary outcome was a return visit to the ED within five days. We conducted logistic regression analyses to evaluate the factors influencing ED return visit.

RESULTS

This study included 1318 FN patients, 154 (12.1%) of whom revisited the ED within five days. Patients (53.3%) revisited the ED owing to persistent fever (56.5%), with no intensive care unit admission and only one mortality case who was discharged hopelessly. Multivariable analysis revealed that shock index >0.9 (odds ratio [OR]: 1.45, 95% confidence interval [CI], 1.01-2.10), thrombocytopenia (<100 × 10³/uL) (OR: 1.64, 95% CI, 1.11-2.42), and lactic acid level > 2 mmol/L (OR: 1.51, 95% CI, 0.99-2.25) were associated with an increased risk of a return visit to the ED, whereas being transferred into the ED from other hospitals (OR: 0.08; 95% CI, 0.005-0.38) was associated with a decreased risk of a return visit to the ED.

CONCLUSION

High shock index, lactic acid, thrombocytopenia, and ED arrival type can predict return visits to the ED in chemotherapy-induced FN patients.

Pediatric emergency revisits of children with COVID-19

OBJECTIVE

This study was conducted to reveal the characteristics of pediatric emergency revisits of children with COVID-19 and the factors associated with clinical worsening and hospitalization at the revisit.

MATERIALS AND METHODS

In pediatric emergency visits of children between July 2020 and March 2021 with COVID-19, the patients who had a revisit within 7 days were included in the study. Demographic and clinical characteristics, test results, and the relationship of these variables with clinical worsening and hospitalization at the revisit were investigated.

RESULTS

In 6779 children with COVID-19, 284 (4.1%) patients included in the study. 51.8% of the patients were male, the median age was 11.1 years, and median time to revisit time was 2.0 days. The rates of clinical worsening and hospitalization were 9.1% and 14.7%, respectively. Children younger than 24 months and those with chronic diseases were more commonly hospitalized at the revisit. Though the frequency of laboratory and radiologic testing at the revisit was significantly increased compared to the first presentation, tests did not play an important role in the decision-making processes. More than 85% of patients were clinically mild at the first presentation and revisit.

CONCLUSIONS

Children with a diagnosis of COVID-19 can revisit the emergency without evident clinical worsening. Since revisits cause increase in frequency of laboratory and radiological testing, preventing unnecessary revisits of children with COVID-19 can reduce the workload and cost of health care services. We may consider changing our perspective on revisit patients to make decisions based on clinical findings instead of obtaining for more laboratory tests.

High-risk Return Visits to United States Emergency Departments, 2010–2018

Introduction: Although factors related to a return visit to the emergency department (ED) have been reported, only a few studies have examined “high-risk” ED revisits with serious adverse outcomes. In this study we aimed to describe the incidence and trend of high-risk ED revisits in United States EDs and to investigate factors associated with these revisits. Methods: We obtained data from the National Hospital Ambulatory Medical Care Survey (NHAMCS), 2010–2018. Adult ED revisits within 72 hours of a previous discharge were identified using a mark on the patient record form. We defined high-risk revisits as revisits with serious adverse outcomes, including intensive care unit admissions, emergency surgery, cardiac catheterization, or cardiopulmonary resuscitation (CPR) during the return visit. We performed analyses using descriptive statistics and multivariable logistic regression, accounting for NHAMCS’s complex survey design. Results: Over the nine-year study period, there were an estimated 37,700,000 revisits, and the proportion of revisits in the entire ED population decreased slightly from 5.1% in 2010 to 4.5% in 2018 (P for trend = 0.02). By contrast, there were an estimated 827,000 high-risk ED revisits, and the proportion of high-risk revisits in the entire ED population remained stable at approximately 0.1%. The mean age of these high-risk revisit patients was 57 years, and 43% were men. Approximately 6% of the patients were intubated, and 13% received CPR. Most of them were hospitalized, and 2% died in the ED. Multivariable analysis showed that older age (65+ years), Hispanic ethnicity, daytime visits, and arrival by ambulance during the revisit were independent predictors of high-risk revisits. Conclusion: High-risk revisits accounted for a relatively small fraction (0.1%) of ED visits. Over the period of the NHAMCS survey between 2010-2018, this fraction remained stable. We identified factors during the return visit that could be used to label high-risk revisits for timely intervention.

Comparison of outcomes in emergency department revisiting patients before and after coronavirus disease 2019 epidemic

BACKGROUND AND IMPORTANCE

The outbreak of COVID-19 challenged the global health system and specifically impacted the emergency departments (EDs). Studying the quality indicators of ED care under COVID-19 has been a necessary task, and ED revisits have been used as an indicator to monitor ED performance.

OBJECTIVES

The study investigated whether discrepancies existed among ED revisiting cases before and after COVID-19 and whether the COVID-19 epidemic was a predictor of poor outcomes of ED revisits.

DESIGN

Retrospective study.

SETTINGS AND PARTICIPANTS

We used electronic health records data from a tertiary medical center. Data of patients with 72-h ED revisit after the COVID-19 epidemic were collected from February 2020 to June 2020 and compared with those of patients before COVID-19, from February 2019 to June 2019.

OUTCOME MEASURES AND ANALYSIS

The investigated outcomes included hospital admission, ICU admission, out-of-hospital cardiac arrest, and subsequent inhospital mortality. Univariate and multivariate logistic regression models were used to identify independent predictors of 72-h ED revisit outcomes.

MAIN RESULTS

In total, 1786 patients were enrolled in our study - 765 in the COVID group and 1021 in the non-COVID group. Compared with the non-COVID group, patients in the COVID group were younger (53.9 vs. 56.1 years old; P = 0.002) and more often female (66.1% vs. 47.3%; P < 0.001) and had less escalation of triage level (11.6% vs. 15.0%; P = 0.041). The hospital admission and inhospital mortality rates in the COVID and non-COVID groups were 33.9% vs. 32.0% and 2.7% vs. 1.5%, respectively. In the logistic regression model, the COVID-19 period was significantly associated with inhospital mortality (adjusted odds ratio, 2.289; 95% confidence interval, 1.059-4.948; P = 0.035).

CONCLUSION

Patients with 72-h ED revisits showed distinct demographic and clinical patterns before and after the COVID-19 epidemic; the COVID-19 period was an independent predictor of increased inhospital mortality.

A Machine Learning Model for Predicting Unscheduled 72 h Return Visits to the Emergency Department by Patients with Abdominal Pain

Seventy-two-hour unscheduled return visits (URVs) by emergency department patients are a key clinical index for evaluating the quality of care in emergency departments (EDs). This study aimed to develop a machine learning model to predict 72 h URVs for ED patients with abdominal pain. Electronic health records data were collected from the Chang Gung Research Database (CGRD) for 25,151 ED visits by patients with abdominal pain and a total of 617 features were used for analysis. We used supervised machine learning models, namely logistic regression (LR), support vector machine (SVM), random forest (RF), extreme gradient boosting (XGB), and voting classifier (VC), to predict URVs. The VC model achieved more favorable overall performance than other models (AUROC: 0.74; 95% confidence interval (CI), 0.69–0.76; sensitivity, 0.39; specificity, 0.89; F1 score, 0.25). The reduced VC model achieved comparable performance (AUROC: 0.72; 95% CI, 0.69–0.74) to the full models using all clinical features. The VC model exhibited the most favorable performance in predicting 72 h URVs for patients with abdominal pain, both for all-features and reduced-features models. Application of the VC model in the clinical setting after validation may help physicians to make accurate decisions and decrease URVs.