Imaging in patients suspected of non-traumatic pulmonary disease at the emergency department Chest X-ray or ultra-low-dose CT

The primary aim of this thesis was to study the impact on patient outcomes of replacing CXR by ultra-low-dose chest CT (ULDCT) in patients suspected of non-traumatic pulmonary disease at the emergency department (ED).
This was a multicentre, pragmatic, non-inferiority randomised controlled trial (RCT) comparing ULDCT to CXR in consecutive. During randomly assigned periods of one calendar month, ULDCT or CXR was used as the imaging strategy.
Between January 31, 2017, and May 31, 2018, 2418 consecutive patients (ULDCT: 1208, CXR: 1210) were included. We found a small but significant difference in the primary outcome measure functional health at 28 days: PCS score was 37.0 in the ULDCT group compared to 35.9 in the CXR group, a difference of 1.1 points (95% lower CI: 0.003). There were minimal differences in ED length of stay, hospital admissions, hospital length of stay, mental health, and mortality rates. After ULDCT significantly less additional imaging was done: ULDCT 39.3% versus CXR 53.9% of patients. More ULDCT patients were in follow-up after 28 days because of incidental findings: ULDCT 2.2% versus CXR 0.3%.
CAP was more often diagnosed at ED discharge after ULDCT than after CXR (22.0% versus 16.4%), with subsequent confirmation of diagnosis at day 28 (ULDCT 19.4% versus CXR 14.7). Congestive heart failure was more often diagnosed with CXR at day 28 (ULDCT 5.7% versus CXR 9.6%).
The results of our trial do not support the routine use of ULDCT in the work-up of patients presenting with non-traumatic pulmonary disease at the ED.