The goal of this study is to assess how safe it is for critically ill patients in the Intensive Care Unit (ICU) to undergo a PET scan. A PET scan is a type of medical imaging used to help determine why a patient is sick. It is similar to a CT scan but involves a small amount of radioactivity to highlight areas of concern in the body.

For a PET scan, patients need to be transported from the ICU to the scanning room, which can be risky because ICU patients are often very fragile. After a patient gets the PET scan injection, their body gives off a small amount of radiation for a short time. Because of this, doctors and nurses have to keep some distance to protect themselves. This means they keep an eye out for the patient from a bit further away than normal. This makes the procedure slightly riskier, especially for very sick patients.

This study aims to answer the question:

Is getting a PET scan riskier for ICU patients than a regular CT scan?

All patients in this study will continue to receive their usual critical care. Researchers will closely monitor the scanning process to evaluate its safety.

PET scans are already widely used to detect cancer, but new advancements may allow us to use them more often to diagnose infections. Before this can become routine practice, we need to ensure that PET scanning is just as safe as other commonly used imaging techniques. This study will assess all ICU patients undergoing a PET scan-regardless of the reason for the scan-to determine how safe the procedure is in critically ill individuals.

Inclusion Criteria:

• Patients receiving PET/CT during ICU admission (any indication)
• Patients undergoing CT Thorax/Abdomen (matched cohort)

Exclusion Criteria:

• CT-scan for any acute indication (acute danger to vital parameters).
• CT-Cerebrum
• Registrion in the dutch Objection to medical research registry.

Only patients admitted to the Intensive Care Unit (ICU) will be studied.

All IPD that underlie the results in the publication will be made available upon request by other researchers.

Once data collection has been completed, data will be made available on request. Ergo circa April 2027.

Only data gathered to answer the primary research question posed in this study will be made available and only upon request via the primary researcher.