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.

C-reactive Protein and Risk of Right Ventricular Dysfunction and Mortality in Patients With Acute Symptomatic Pulmonary Embolism.

BACKGROUND: Right ventricle (RV) dysfunction increases the risk of death from pulmonary embolism (PE). C-reactive protein (CRP) might identify RV inflammation and dysfunction in patients with PE. METHODS: This cohort study enrolled consecutive stable patients with acute PE between 2017 and 2023. We stratified patients by quartiles of CRP. We evaluated the association between CRP quartiles and the presence of RV dysfunction, and used multivariable models to assess for an association between CRP and the outcomes of all-cause and PE-specific mortality during the 30 days of follow-up after PE diagnosis. RESULTS: The study included 633 stable patients with PE. Patients without RV dysfunction had significantly lower median (IQR) CRP levels compared with patients with RV dysfunction (n=509, 31.7 [10.0-76.4]mg/L vs n=124, 45.4 [16.0-111.4]mg/L; P=0.018). CRP showed a statistically significant positive association with the presence of RV dysfunction (P<0.01). On multivariable analysis, CRP level was not significantly associated with 30-day all-cause mortality (adjusted odds ratio [OR] per mg/L increment, 1.00; 95% CI, 1.00-1.01; P=0.095), but higher CRP was associated with significantly higher PE-related mortality (adjusted OR, 1.01; 95% CI, 1.00-1.01; P=0.026). Compared with patients in CRP quartile 1, patients in quartiles 2, 3, and 4 had a stepwise increase in the adjusted odds of 30-day all-cause death of 2.41 (P=0.148), 3.04 (P=0.062), and 3.15 (P=0.052), respectively. CONCLUSIONS: As an indicator of RV dysfunction, CRP may improve risk stratification algorithms for hemodynamically stable patients with acute symptomatic PE.

Management of high-risk pulmonary embolism in the emergency department: A narrative review.

BACKGROUND: High-risk pulmonary embolism (PE) is a complex, life-threatening condition, and emergency clinicians must be ready to resuscitate and rapidly pursue primary reperfusion therapy. The first-line reperfusion therapy for patients with high-risk PE is systemic thrombolytics (ST). Despite consensus guidelines, only a fraction of eligible patients receive ST for high-risk PE. OBJECTIVE: This review provides emergency clinicians with a comprehensive overview of the current evidence regarding the management of high-risk PE with an emphasis on ST and other reperfusion therapies to address the gap between practice and guideline recommendations. DISCUSSION: High-risk PE is defined as PE that causes hemodynamic instability. The high mortality rate and dynamic pathophysiology of high-risk PE make it challenging to manage. Initial stabilization of the decompensating patient includes vasopressor administration and supplemental oxygen or high-flow nasal cannula. Primary reperfusion therapy should be pursued for those with high-risk PE, and consensus guidelines recommend the use of ST for high-risk PE based on studies demonstrating benefit. Other options for reperfusion include surgical embolectomy and catheter directed interventions. CONCLUSIONS: Emergency clinicians must possess an understanding of high-risk PE including the clinical assessment, pathophysiology, management of hemodynamic instability and respiratory failure, and primary reperfusion therapies.

Clinical outcomes in hospitalized plasma and platelet transfusion recipients prior to and following widespread blood donor SARS-CoV-2 infection and vaccination.

BACKGROUND: The safety of transfusion of SARS-CoV-2 antibodies in high plasma volume blood components to recipients without COVID-19 is not established. We assessed whether transfusion of plasma or platelet products during periods of increasing prevalence of blood donor SARS-CoV-2 infection and vaccination was associated with changes in outcomes in hospitalized patients without COVID-19. METHODS: We conducted a retrospective cohort study of hospitalized adults who received plasma or platelet transfusions at 21 hospitals during pre-COVID-19 (3/1/2018-2/29/2020), COVID-19 pre-vaccine (3/1/2020-2/28/2021), and COVID-19 post-vaccine (3/1/2021-8/31/2022) study periods. We used multivariable logistic regression with generalized estimating equations to adjust for demographics and comorbidities to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among 21,750 hospitalizations of 18,584 transfusion recipients without COVID-19, there were 697 post-transfusion thrombotic events, and oxygen requirements were increased in 1751 hospitalizations. Intensive care unit length of stay (n = 11,683) was 3 days (interquartile range 1-5), hospital mortality occurred in 3223 (14.8%), and 30-day rehospitalization in 4144 (23.7%). Comparing the pre-COVID, pre-vaccine and post-vaccine study periods, there were no trends in thromboses (OR 0.9 [95% CI 0.8, 1.1]; p = .22) or oxygen requirements (OR 1.0 [95% CI 0.9, 1.1]; p = .41). In parallel, there were no trends across study periods for ICU length of stay (p = .83), adjusted hospital mortality (OR 1.0 [95% CI 0.9-1.0]; p = .36), or 30-day rehospitalization (p = .29). DISCUSSION: Transfusion of plasma and platelet blood components collected during the pre-vaccine and post-vaccine periods of the COVID-19 pandemic was not associated with increased adverse outcomes in transfusion recipients without COVID-19.

Addressing the rising trend of high-risk pulmonary embolism mortality: Clinical and research priorities.

BACKGROUND: Deaths from high-risk pulmonary embolism (PE) appear to have increased in the US over the last decade. Modifiable risks contributing to this worrisome trend present opportunities for physicians, researchers, and healthcare policymakers to improve care. METHODS: We sought to contextualize contemporary, high-risk PE epidemiology and examine clinical trials, quality improvement opportunities, and healthcare policy initiatives directed at reducing mortality. RESULTS: We observed significant and modifiable excess mortality due to high-risk PE. We identified several opportunities to improve care including: (1) rapid translation of forthcoming data on reperfusion strategies into clinical practice; (2) improved risk stratification tools; (3) quality improvement initiatives to address presumptive anticoagulation practice gaps; and (3) adoption of health policy initiatives to establish pulmonary embolism response teams and address the social determinants of health. CONCLUSION: Addressing knowledge and practice gaps in intermediate and high-risk PE management must be prioritized and informed by forthcoming high-quality data. Implementation efforts are needed to improve acute PE management and resolve treatment disparities.

Disposition of emergency department patients with acute pulmonary embolism after ambulance arrival.

Objective: Most outpatients with pulmonary embolism (PE) are diagnosed in the emergency department (ED). The relationship between means of arrival, site of diagnosis, and disposition in ED patients with PE is unknown. We compared discharge home between patients arriving by emergency medical services (EMS) and those arriving by other means. Within the EMS cohort, we compared those with a recent PE diagnosis in the outpatient clinic setting to those who were diagnosed with PE in the ED. Methods: This study was a secondary analysis of a retrospective cohort that included all adult, non-pregnant ED patients treated for acute PE across 21 community EDs from January 2013 to April 2015. The primary outcome was discharge home within 24 h of ED registration; we also examined mortality. We described associations with patient arrival method and other patient characteristics. Results: Among 2996 ED patient encounters with acute PE, 644 (21.5%) arrived by EMS. This group had a lower frequency of discharge (9.2% vs 26.4%) and higher 30-day all-cause mortality (8.7% vs 3.1%) than their counterparts (p < 0.001 for both). These associations remained after adjusting for confounding variables. Among the EMS cohort, 14 patients (2.2%) arrived with a PE diagnosis recently made in the outpatient setting. Conclusion: Patients with PE who arrived at the ED by EMS were less likely to be discharged home within 24 h and more likely to die within 30 days than those who arrived by other means. Less than 3% of the EMS group had been diagnosed with PE before ED arrival.

Accuracy of Medical Student Measurements of CT Right-to-Left Ventricular Diameter in Patients with Acute Pulmonary Embolism.

Objectives: Acute pulmonary embolism (PE) is a common disease, necessitating risk stratification to determine management. A right ventricle (RV) to left ventricle (LV) diameter ratio ≥1.0 on computed tomography pulmonary angiography (CTPA) suggests RV strain, which may indicate a worse prognosis. Two prior studies showed that residents with brief training by a radiologist could accurately measure RV/LV ratio. We assessed whether medical students could accurately measure RV dilatation. Methods: We conducted a post hoc analysis of a retrospective cohort study of adults undergoing management for acute PE at 21 community emergency departments across Kaiser Permanente Northern California from 2013 to 2015. We created a sample, stratified to contain an equal number of patients from each of the 5 PE Severity Index classes. Four medical students measured RV and LV diameter on CTPA after training from an emergency medicine physician and an interventional radiologist. We used Cohen's kappa statistics, Bland-Altman plots, and Pearson correlation coefficients to assess interrater reliability. Results: Of the 108 CTPAs reviewed, 79 (73%) showed RV dilatation and 29 (27%) did not. The kappa statistic for the presence of RV dilatation of the medical students compared to the radiologist showed moderate agreement for 3 medical students (kappa (95% CI): 0.46 (0.21-0.70), 0.49 (0.31-0.68), 0.50 (0.32-0.68)) and fair agreement for 1 medical student (kappa (95% CI): 0.29 (0.10-0.47)). The average interrater differences in RV/LV ratio between a radiologist and each of the 4 medical students were -0.04, -0.05, 0.04, and 0.24. Pearson correlation coefficients were 0.87, 0.80, 0.74, and 0.78, respectively, indicating moderate correlation (P < .001 for all). Conclusion: Medical students were able to identify RV dilatation on CTPA in moderate agreement with that of a radiologist. Further study is needed to determine whether medical student accuracy could improve with additional training.

Barriers and Facilitators to the Outpatient Management of Low-risk Pulmonary Embolism From the Emergency Department.

STUDY OBJECTIVE: Although recommended by professional society guidelines, outpatient management of low-risk pulmonary embolism (PE) from emergency departments (EDs) in the US remains uncommon. The objective of this study was to identify barriers and facilitators to the outpatient management of PE from the ED using implementation science methodology. METHODS: We conducted semistructured interviews with a purposeful sample of emergency physicians using maximum variation sampling, aiming to recruit physicians with diverse practice patterns regarding the management of low-risk PE. We developed an interview guide using the implementation science frameworks-the Consolidated Framework for Implementation Research and the Theoretical Domains Framework. Interviews were recorded, transcribed, and analyzed in an iterative process. RESULTS: We interviewed 26 emergency physicians from 11 hospital systems, and the participants were diverse with regard to years in practice, practice setting, and engagement with outpatient management of PE. Although outer setting determinants, such as medicolegal climate, follow-up, and insurance status were universal, our participants revealed that the importance of these determinants were moderated by individual-level and inner setting determinants. Prominent themes included belief in consequences, belief in capabilities, and institutional support and culture. Inertia of clinical practice and complexity of the process were important subthemes. CONCLUSION: In this qualitative study, clinicians reported common barriers and facilitators that initially focused on outer setting and external barriers but centered on clinician beliefs, fear, and local culture. Efforts to increase outpatient treatment of select patients with acute PE should be informed by these barriers and facilitators, which are aligned with the deimplementation theory.

Prevalence of and Eligibility for Surveillance Without Anticoagulation Among Adults With Lower-Risk Acute Subsegmental Pulmonary Embolism.

Importance: Approximately 8% of acute pulmonary emboli are confined to the subsegmental arteries. The 2016 and 2021 American College of Chest Physicians (CHEST) guidelines and expert panel reports suggest the use of structured surveillance without anticoagulation for select ambulatory patients with subsegmental pulmonary embolism who do not have active cancer, deep vein thrombosis, impaired cardiopulmonary reserve, marked symptoms, or increased risk of recurrent venous thromboembolism; however, guideline uptake in community practice is unknown, as is the proportion of outpatients eligible for surveillance. Objective: To describe the prevalence of surveillance among outpatients with acute subsegmental pulmonary embolism and to estimate the proportion of patients eligible for structured surveillance using modified CHEST criteria. Design, Setting, and Participants: This retrospective cohort study was conducted across 21 US community hospitals in the Kaiser Permanente Northern California integrated health system from January 1, 2017, to December 31, 2021. Adult outpatients with acute subsegmental pulmonary embolism were included. Patients with the following higher-risk characteristics were excluded: codiagnoses requiring hospitalization, non-low-risk vital signs (ie, systolic blood pressure <90 mm Hg, pulse ≥110 bpm, or peripheral cutaneous pulse oximetry ≤92%), prediagnosis anticoagulant use, or hospice care. Data analysis was performed from November 2022 to February 2023. Main Outcomes and Measures: The main outcomes were the (1) prevalence of surveillance and (2) eligibility for surveillance using 2 sets of criteria: the CHEST criteria modified by excluding patients with higher-risk characteristics or right ventricular dysfunction and a stricter set of criteria requiring age younger than 65 years and no more than 1 embolus. The prevalence of structured surveillance was calculated and the proportion of patients eligible for surveillance was estimated. Results: Of the 666 outpatients with acute subsegmental pulmonary embolism included in this study, 229 with lower-risk characteristics were examined. Their median age was 58 (IQR, 42-68) years; more than half were men (120 [52.4%]) and self-identified as non-Hispanic White (128 [55.9%]). Six patients (2.6%) were initially not treated with anticoagulants. Among the lower-risk cohort, only 1 patient (0.4% [95% CI, 0.01%-2.4%]) underwent structured surveillance, without 90-day sequelae. Thirty-five patients (15.3% of the lower-risk group and 5.3% of the full cohort) were surveillance eligible using modified CHEST criteria. Fifteen patients (6.6% of the lower-risk group and 2.3% of the full cohort) were surveillance eligible using stricter criteria. Conclusions and Relevance: In this cohort study of lower-risk outpatients with subsegmental pulmonary embolism, few were eligible for structured surveillance, and only a small proportion of eligible patients underwent surveillance despite the CHEST guideline. If forthcoming trials find surveillance safe and effective, substantial uptake into clinical practice may require more than passive diffusion.

CA FIRST (California Febrile Infant Risk Stratification Tool) Algorithm Development in a Learning Health System.

Introduction There is considerable variation in the approach to infants presenting to the emergency department (ED) with fever. The authors' primary aim was to develop a robust set of algorithms using community ED data to inform modifications of broader clinical guidance. Methods The authors report the development of California Febrile Infant Risk Stratification Tool (CA FIRST) using key components of the Roseville Protocol (ROS) and American Academy of Pediatrics (AAP) Clinical Practice Guideline (CPG). Expanded guidance was derived using a retrospective analysis of a cohort of 3527 febrile infants aged 7-90 days presenting to any Kaiser Permanente Northern California ED between 2010 and 2019 who underwent a core febrile infant evaluation. Results Melding ROS and AAP CPG algorithms in infants 7-60 days old, CA FIRST Algorithms had comparable performance characteristics to ROS and AAP CPG. CA FIRST enhancements included guidance on febrile infants 61-90 days old, high-risk infants, infants with bronchiolitis, and infants who received immunizations within the prior 48 hours. This retrospective analysis revealed that of 235 febrile infants 22-90 days old with respiratory syncytial virus and 221 who had fever in the 48 hours following vaccination, there were no cases of invasive bacterial infection. Discussion CA FIRST is a set of 13 algorithms providing a thoughtful and flexible approach to the febrile infant while minimizing unnecessary interventions. Conclusions CA FIRST Algorithms empower clinicians to manage most febrile infants. Algorithms are being modified as new data become available, imparting useful and ever-current educational information within a learning health care system.

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.

Bilateral Emboli and Highest Heart Rate Predict Hospitalization of Emergency Department Patients With Acute, Low-Risk Pulmonary Embolism.

STUDY OBJECTIVE: Some patients with acute pulmonary embolism (PE) will suffer adverse clinical outcomes despite being low risk by clinical decision rules. Emergency physician decisionmaking processes regarding which low-risk patients require hospitalization are unclear. Higher heart rate (HR) or embolic burden may increase short-term mortality risk, and we hypothesized that these variables would be associated with an increased likelihood of hospitalization for patients designated as low risk by the PE Severity Index. METHODS: This was a retrospective cohort study of 461 adult emergency department (ED) patients with a PE Severity Index score of fewer than 86 points. Primary exposures were the highest observed ED HR, most proximal embolus location (proximal vs distal), and embolism laterality (bilateral vs unilateral PE). The primary outcome was hospitalization. RESULTS: Of 461 patients meeting inclusion criteria, most (57.5%) were hospitalized, 2 patients (0.4%) died within 30 days, and 142 (30.8%) patients were at elevated risk by other criteria (Hestia criteria or biochemical/radiographic right ventricular dysfunction). Variablesassociated with an increased likelihood of admission were highest observed ED HR of ≥110 beats/minute (vs HR <90 beats/min) (adjusted odds ratio [aOR] 3.11; 95% confidence interval [CI] 1.07 to 9.57), highest ED HR 90 to 109 (aOR 2.03; 95% CI 1.18-3.50) and bilateral PE (aOR 1.92; 95% CI 1.13 to 3.27). Proximal embolus location was not associated with the likelihood of hospitalization (aOR 1.19; 95% CI 0.71 to 2.00). CONCLUSIONS: Most patients were hospitalized, often with recognizable high-risk characteristics not accounted for by the PE Severity Index. Highest ED HR of ≥90 beats/min and bilateral PE were associated with a physician's decision for hospitalization.

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.

Bilateral Tubal Pregnancies Presenting 11 Days Apart: A Case Report.

INTRODUCTION: Ectopic pregnancy is the most common cause of maternal mortality in the first trimester. Bilateral tubal pregnancy is the rarest subset with an estimated incidence of one in 725 to 1,580 ectopic pregnancies. Of the cases of bilateral tubal pregnancy reported in the literature, most were associated with the use of assisted reproductive techniques. Here we present the case of a patient, without a prior history of reproductive technology use, who underwent treatment for a tubal pregnancy and was subsequently found to have a second, contralateral tubal pregnancy 11 days later. CASE REPORT: A 35-year-old female gravida eight para two with a history of left tubal pregnancy and salpingectomy 11 days prior, presented to the emergency department (ED) with two days of left lower and upper quadrant abdominal pain. The patient's last menstrual period had been several months prior. A physical examination revealed left lower quadrant abdominal tenderness, rebound, guarding, and left adnexal tenderness. Her vital signs were unremarkable, and her laboratory studies revealed normal white blood cell and hemoglobin values. Her human chorionic gonadotropin had tripled from her last presentation 11 days prior. Transvaginal ultrasound showed a possible ectopic pregnancy adjacent to the right ovary. She promptly underwent a right salpingectomy. Pathology findings confirmed a tubal pregnancy, and the patient's postoperative course was uneventful. CONCLUSION: This case highlights the importance of maintaining a high index of suspicion for ectopic pregnancy in all biologically female patients of reproductive age who present to the ED with abdominal pain.

CT Use Reduction In Ostensive Ureteral Stone (CURIOUS).

INTRODUCTION: Computed tomography (CT) is performed in over 90% of patients diagnosed with ureteral stones, but only 10% of patients presenting to the emergency department (ED) with acute flank pain are hospitalized for a clinically important stone or non-stone diagnosis. Hydronephrosis can be accurately detected using point-of-care ultrasound and is a key predictor of ureteral stone and risk of subsequent complications. The absence of hydronephrosis is insufficient to exclude a stone. We created a sensitive clinical decision rule to predict clinically important ureteral stones. We hypothesized that this rule could identify patients at low risk for this outcome. METHODS: We conducted a retrospective cohort study in a random sample of 4000 adults who presented to one of 21 Kaiser Permanente Northern California EDs and underwent a CT for suspected ureteral stone from 1/1/2016 to 12/31/2020. The primary outcome was clinically important stone, defined as stone resulting in hospitalization or urologic procedure within 60 days. We used recursive partition analysis to generate a clinical decision rule predicting the outcome. We estimated the C-statistic (area under the curve), plotted the receiver operating characteristic (ROC) curve for the model, and calculated sensitivity, specificity, and predictive values of the model based on a risk threshold of 2%. RESULTS: Among 4000 patients, 354 (8.9%) had a clinically important stone. Our partition model resulted in four terminal nodes with risks ranging from 0.4% to 21.8%. The area under the ROC curve was 0.81 (95% CI 0.80, 0.83). Using a 2% risk cut point, a clinical decision tree including hydronephrosis, hematuria, and a history of prior stones predicted complicated stones with sensitivity 95.5% (95% CI 92.8%-97.4%), specificity 59.9% (95% CI 58.3%-61.5%), positive predictive value 18.8% (95% CI 18.1%-19.5%), and negative predictive value 99.3% (95% CI 98.8%-99.6%). CONCLUSIONS: Application of this clinical decision rule to imaging decisions would have led to 63% fewer CT scans with a miss rate of 0.4%. A limitation was the application of our decision rule only to patients who underwent CT for suspected ureteral stone. Thus, this rule would not apply to patients who were thought to have ureteral colic but did not receive a CT because ultrasound or history were sufficient for diagnosis. These results could inform future prospective validation studies.