P028: The prevalence of pathological findings identified by next day abdominal ultrasound in patients discharged from the ED

Abstract

Introduction: Abdominal pain is the most common complaint in the emergency department (ED), accounting for approximately 7% of all visits. Of the patients discharged from the ED with this complaint, 25% will carry a diagnosis of undifferentiated abdominal pain and many will subsequently have an outpatient ultrasound for further assessment. The objective of this study was to determine the proportion of outpatient ultrasounds with findings requiring intervention within 14 days. Methods: This was a retrospective chart review of non-pregnant patients aged 18 to 40 years, presenting to an academic ED (annual census 65,000) with an abdominal complaint for whom the emergency physician arranged an outpatient (next day) abdominal ultrasound from November 2014 to November 2015. Data was abstracted by trained research personnel independently and in duplicate and inter-rater agreement was calculated for 25% of charts. Results: Of the 315 included patients, 261 (82.9%) were female and mean (SD) age was 28.5 (5.9) years. 28 (8.9%) patients had ultrasounds requiring intervention within 14 days. Of these, 8 (28.6%) had appendicitis, 6 (21.4%) had cholecystitis, 5 (17.9%) had gynecological, 5 (17.9%) had urological and 4 (14.3%) had gastrointestinal diagnoses. However, 15 (53.6%) patients requiring intervention within 14 days had symptoms which had improved or resolved at the time of the US. Of the 287 (91.1%) patients not requiring intervention, 92 (32.1%) had unchanged, 120 (41.8%) had improved, 52 (18.1%) had resolved and 5 (1.7%) had worsened symptoms at the time of follow-up. Of the non-intervention patients, 13 (4.5%) required alternative imaging (CT scan). Conclusion: The large majority of patients with abdominal pain discharged from the ED with planned next day US were found to have either no pathology or pathology that did not require further ED management. However, 8.9% of patients had pathological findings requiring intervention within 14 days and half of these had symptoms that had resolved or improved at the time of the US. Next day US imaging remains a viable option for identifying patients with serious pathology not appreciated at the time of their ED visit.