OPTimal IMAging strategy in patients suspected of non-traumatic pulmonary disease at the ED: Chest X-ray or CT

Chest X-ray has been the standard imaging method for patients suspected of
non-traumatic pulmonary disease in the Emergency department for years.
Recently, ultra-low-dose chest computed tomography (ULD chest CT) has been
introduced that provides substantially more detailed information on pulmonary
conditions that may cause pulmonary complaints, with a dose in the order of the
chest X-ray (0.1 mSv vs 0.05mSv).

This ULD chest CT most likely will lead to more timely diagnoses and improved
patient management. Therefore replacement of chest X-ray by ULD chest CT seems
a logical step. However, this assumption of more timely diagnoses and improved
patient management has not been substantiated. Further, the use of CT leads to
higher direct costs and its availability is limited. Importantly, incidental
findings on CT lead to additional examinations and associated costs and burden
while these findings will be beneficial in only a minority of patients.
Therefore it is necessary to compare both strategies to determine whether it is
effective to replace the current diagnostic strategy with chest X-ray for ULD
chest CT in patients suspected of non traumatic pulmonary disease at the
Emergency department.

Primary objective
To evaluate the effects, in terms of patient-related health outcomes and costs,
of replacing chest X-ray by ULD chest CT in the diagnostic work-up of patients
suspected of non-traumatic pulmonary disease at the ED.

Secondary objective
To evaluatie wether the replacement of chest X-ray by ultra-low-dose chest CT
(ULD chest CT) in the diagnostic work-up of patients suspected of non-traumatic
pulmonary disease at the Emergency Department leads to more accurate diagnoses
and more timely treatment.
To evaluate, for patients with clinically suspected community-acquired
pneumonia (CAP),
- the diagnostic accuracy and clinical impact of performing ultra-low-dose
plain chest CT as compared to conventional chest X-ray.
- the accuracy of CT versus conventional X-ray to predict the etiology of the
pneumonia.
- the value of new and previously described (molecular) biomarkers for
the diagnosis ande etiology of CAP

A multi-centre, pragmatic, randomized trial comparing chest X-ray to ULD chest
CT in patients suspected of non-traumatic pulmonary disease presenting at the
Emergency department. As both imaging modalities are considered
state-of-the-art, with a radiation dose that is comparable, strategies will
rotate randomly per calendar month. Before imaging informed consent will be
obtained for participation in the study ans using individual patient data for
study purposes.
Embedded in the study is a sub-study for patients suspected of
community-acquired pneumonia.

RISKS ASSOCIATED WITH PARTICIPATION
Both imaging modalities are considered standard-of-care. Patients who
participate in this RCT and will be allocated to the ULD chest CT arm have an
associated additional ionizing radiation dose of 0.05 mSV. This is the
equivalent of one chest X-rays (0.05 mSv). The collection of three additional
tubes of blood totals 11.5 milliliter. This is a very small amount, being less
than 1% of the total volume of blood and is therefore not dangerous.

LONG AND SHORT TERM BENEFITS
With ULD chest CT an increase in diagnostic efficiency is expected, which will
result in an increase in treatment efficiency, influencing admission policy,
hospital stay and recovery of the patient. A side effect of ULD chest CT will
be the increase in unexpected findings, especially lung nodules, that will need
extra investigations to rule out a serious causes.