Clinical trial NCT06043726: Diagnostic Accuracy of Arterial-alveolar Oxygen Gradient in Low Risk Patients With Suspected Pulmonary Embolism
Official title: Diagnostic Accuracy of Arterial-alveolar Oxygen Gradient in Low Risk Patients With Suspected Pulmonary Embolism
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Pulmonary Embolism
Keywords: A-a gradient
Lead sponsor: Franciscus Gasthuis
Sponsor class: OTHER
First posted: 2023-09-21
Enrollment: 230
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: All patients that present in our emergency department with suspicion of pulmonary embolism

Brief summary: Introduction:

The diagnosis of pulmonary embolism (PE) is a challenge in the Emergency Department. D-dimer based diagnostic algorithms for PE have a very high sensitivity, but rely upon a vast amount of CT angiography and potentially unnecessary exposure to radiation. An accurate diagnostic algorithm that does not involve d-dimer testing might reduce this burden.

An abnormal Alveolar-arterial oxygen gradient (A-a gradient) seems to increase the chance of PE. However, a normal A-a gradient on its own does not exclude the diagnosis. In this paper, the accuracy of A-a gradient testing and a combination of Years criteria with A-a gradient testing will be assessed.

Methods:

This is a prospective, single center, observational study. All patients that present at our emergency department from September 2022 until September 2023 with a suspicion of pulmonary embolism will be analyzed for eligibility and included in the study after informed consent. The aim is to include at least 230 patients in the study.

Analysis: The primary outcome is the diagnostic accuracy of a YEARS and A-a gradient based algorithm for pulmonary embolism. The secondary outcome is the potential decrease in performed imaging in order to exclude pulmonary embolism.

Valorisation An accurate A-a gradient-based algorithm for pulmonary embolism in low risk patients will be a step towards an improved clinical risk score. We aim to reduce the amount of diagnostic imaging, i.e. CT-angiography. Meaning less, potentially unnecessary, exposure to radiation for the patient. Furthermore, it could lower healthcare costs by reducing expensive diagnostic imaging.


Eligibility criteria: Inclusion Criteria:

* Patient with suspected pulmonary embolism
* Emergency department D-dimer result available
* Arterial blood gas available

Exclusion Criteria:

* Patients without documented oxygen suppletion durig blood gas measurement
* Patients without documented and insufficient data to calculate YEARS criteria
* Pregnancy

Primary outcomes:
measure: Diagnostic accuracy of a combination of a normal Alveolar-Arterial Oxygen Gradient with negative YEARS criteria in patients with suspected pumonary embolism
timeFrame: At submission in the Emergency Department
Secondary outcomes:
measure: How many CT-scans would have been avoided if the algorithm was used in normal practice
timeFrame: At submission in the Emergency Department
Other outcomes:
Locations:
city: Rotterdam
country: Netherlands
facility: Franciscus Gasthuis
Study officials:
affiliation: Franciscus Gasthuis
name: Sander Mol
role: STUDY_CHAIR
References:
citation: van der Hulle T, Cheung WY, Kooij S, Beenen LFM, van Bemmel T, van Es J, Faber LM, Hazelaar GM, Heringhaus C, Hofstee H, Hovens MMC, Kaasjager KAH, van Klink RCJ, Kruip MJHA, Loeffen RF, Mairuhu ATA, Middeldorp S, Nijkeuter M, van der Pol LM, Schol-Gelok S, Ten Wolde M, Klok FA, Huisman MV; YEARS study group. Simplified diagnostic management of suspected pulmonary embolism (the YEARS study): a prospective, multicentre, cohort study. Lancet. 2017 Jul 15;390(10091):289-297. doi: 10.1016/S0140-6736(17)30885-1. Epub 2017 May 23.
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