The fundamental principle is that ICU referral should be considered for any patient with actual or threatened failure of one or more organ systems. Critically, you should refer when organ failure appears imminent — not only when it is fully established. Delayed referral consistently leads to worse outcomes. Patients who arrive in ICU in extremis after prolonged ward deterioration are significantly harder to stabilise than those referred early.

The ABCDE framework provides the structure for identifying critical problems. In Mr Jones, the first assessment reveals compromise across multiple domains simultaneously — this is a characteristic pattern of septic shock, which will be confirmed as the module progresses.