This is a retrospective, observational study and will investigate the clinical predictive value of and change in muscle quantity and quality in critically ill patients with severe respiratory failure requiring veno-venous extracorporeal membrane oxygenation (VV-ECMO).

The use of veno-venous extra-corporeal membrane oxygenation (VV-ECMO) for severe respiratory failure - mainly hypoxaemia - has increased over recent years. Similar to the general population in the Intensive Care Unit (ICU), these patients become deconditioned, severely weak (ICU acquired weakness- ICUAW) and require prolonged rehabilitation after disconnection from VV-ECMO. However, data regarding the magnitude of muscle wasting and recovery in this specific group is lacking.

Both poor muscle quantity and quality have been found to be a predictor or poor outcome. As all patients receiving VV-ECMO at our hospital will get an initial CT scan of their chest, abdomen and pelvis, these CT scans will be used to measure muscle quantity and quality of different muscle groups of the abdomen at admission and then using any follow-up CT scan performed within 10 days. In addition, the relationship between the loss of muscle over the course of VV-ECMO and perceived recovery of renal function at ICU discharge will be investigated.

Inclusion Criteria:

• Critically ill patients with Severe Respiratory Failure who required VV-ECMO and had one or more CT scans of their abdomen

Exclusion Criteria:

• Critically ill patients with Severe Respiratory Failure who required VV-ECMO and did not have one or more CT scans of their abdomen
• Critically ill patients with Severe Respiratory Failure who required VV-ECMO who have a poor quality CT scan not analysable by the software

Adult Critically ill patients with severe respiratory failure requiring VV-ECMO