23-hour observation solely for identification of missed injuries after trauma: is it justified?

Background The use of an observation period to identify missed injuries in trauma patients has gained favor in recent years. This study was undertaken in a population of patients with minimal or no identified injuries to determine the following: whether a period of in-patient observation identifies missed injuries; demographic factors associated with missed injuries; and morbidity of missed injuries. Methods Over 4 years at a Level I trauma center, 4,738 patients were observed for 23 hours. Of these patients, 630 were converted to full admission and were reviewed. All medical records were reviewed for reason for observation, reason for conversion to full admission, and presence of missed injury. Results In the 4,738 patients observed, 35 had a missed injury identified. No clinical factors studied were associated with identifying a missed injury. Of the 35 patients that had a missed injury, 21 did not have clinically relevant injuries, whereas the 14 remaining patients did. All of the 14 required prolonged hospital admissions and 9 underwent invasive procedures. Conclusion Of over 4,700 observed trauma patients, less than 0.5% remained hospitalized for significant missed injuries. No factors were identified that predicted missed injuries. Twenty-three-hour observation for the purpose of identifying missed injuries after thorough emergency department evaluation may not be justified.