The Potential Role of Ultrasound in the Work-up of Appendicitis in the Emergency Department.

BACKGROUND: Acute appendicitis is common in the adult emergency department (ED). Computed tomography (CT) scan is frequently used to diagnose this condition, but ultrasound (US)-commonly used in pediatric diagnosis-may also have a role. OBJECTIVES: Review the clinical utility and define the frequency and diagnostic accuracy of US to diagnose appendicitis in an adult population in the ED setting. METHODS: Retrospective cohort study of patients who underwent appendiceal US in an academic, tertiary ED from July 2013-October 2015. RESULTS: There were 174 patients included, of which 39 (22%) had pathology-confirmed appendicitis. There were 25 patients who had an US scan that was positive for appendicitis, 146 (84%) were indeterminate, and 3 (1.7%) were negative. Among patients with a positive US, 25/25 (100%, 95% confidence interval [CI] 84-100%) had appendicitis, 32/146 (22%, 95% CI 16-29%) with an indeterminate US had appendicitis, and 0/3 (0%, 95% CI 0-6.2%) with a negative US had appendicitis. In the 28 definitive cases, US had a sensitivity of 64%, specificity of 2%, positive predictive value of 100%, and negative predictive value of 100%. The likelihood ratio positive and negative were 173 and 0, respectively. CONCLUSION: Our initial data suggest that an US that shows appendicitis seems to be reliable; however, a high prevalence of indeterminate studies limits the diagnostic utility as a universal approach in adult patients in the ED setting. Larger studies are needed to identify which patient populations would benefit from US as the initial imaging modality, what factors contribute to the large numbers of indeterminate results, and if any interventions may reduce the number of indeterminate results.

The Absence of Fever Is Associated With Higher Mortality and Decreased Antibiotic and IV Fluid Administration in Emergency Department Patients With Suspected Septic Shock.

OBJECTIVE: This study evaluates whether emergency department septic shock patients without a fever (reported or measured) receive less IV fluids, have decreased antibiotic administration, and suffer increased in-hospital mortality. DESIGN: This was a secondary analysis of a prospective, observational study of patients with shock. SETTING: The study was conducted in an urban, academic emergency department. PATIENTS: The original study enrolled consecutive adult (aged 18 yr or older) emergency department patients from November 11, 2012, to September 23, 2013, who met one of the following shock criteria: 1) systolic blood pressure less than 90 mm Hg after at least 1L IV fluids, 2) new vasopressor requirement, or 3) systolic blood pressure less than 90 mm Hg and IV fluids held for concern of fluid overload. The current study is limited to patients with septic shock. Patients were grouped as febrile if they had a subjective fever or a measured temperature >100.4°F documented in the emergency department; afebrile patients lacked both. MEASUREMENTS AND MAIN RESULTS: Among 378 patients with septic shock, 207 of 378 (55%; 50-60%) were febrile by history or measurement. Afebrile patients had lower rates of antibiotic administration in the emergency department (81% vs 94%; p < 0.01), lower mean volumes of IV fluids (2,607 vs 3,013 mL; p < 0.01), and higher in-hospital mortality rates (33% vs 11%; p < 0.01). After adjusting for bicarbonate less than 20 mEq/L, lactate concentration, respiratory rate greater than or equal to 24 breaths/min, emergency department antibiotics, and emergency department IV fluids volume, being afebrile remained a significant predictor of in-hospital mortality (odds ratio, 4.3; 95% CI, 2.2-8.2; area under the curve = 0.83). CONCLUSIONS: In emergency department patients with septic shock, afebrile patients received lower rates of emergency department antibiotic administration, lower mean IV fluids volume, and suffered higher in-hospital mortality.

Assessing The Predictive Value of Clinical Factors Used to Determine The Presence of Sepsis Causing Shock in the Emergency Department.

INTRODUCTION: Differentiating shock etiologies is a challenging task in the Emergency Department (ED); even the strongest clinical predictors leave some diagnostic uncertainty. This study sought to establish an evidence base for using clinical covariates in the diagnostic evaluation of septic shock. METHODS: We conducted a prospective, observational study of consecutive ED patients with shock from November 11, 2012 to September 23, 2013. We included all patients at least 18 years old with shock, defined as new vasopressor requirement, systolic blood pressure less than 90 mmHg after at least 1 L of crystalloid or 2 units packed red blood cells, or systolic blood pressure less than 90 mmHg and fluids withheld due to concern for fluid overload. Multivariate logistic regression and recursive partitioning models were constructed, predicting septic cause of shock. The logistic regression model was derived using first 500 patients, and validated with the subsequent 200 patients. RESULTS: In the derivation cohort, 55.6% (95% confidence interval: 51.2%-60.0%) were septic, and 20.8% (17.2%-24.4%) died during hospitalization. The multivariate model (derivation area under the curve = 0.88, validation area under the curve = 0.89) identified predictors of septic shock, including temperature more than 100.4°F (odds ratio 4.6, 2.3-9.2) and history of fever (odds ratio 9.2, 4.4-19.2); however, only 153 of 277 (55.3%, 49.5%-61.2%) patients with septic shock had either of these findings. In the recursive partitioning model, if all predictors were absent, the probability of sepsis causing shock was 21% (16.6%-25.6%). CONCLUSIONS: Clinical data can predict the presence of sepsis causing shock in the ED in most patients. The remaining diagnostic uncertainty provides an opportunity for adding novel diagnostic testing.