ITU

https://www.slideshare.net/ehernandezmd/acute-heart-failure-8475602?next_slideshow=2

http://chicago.medicine.uic.edu/wp-content/uploads/sites/6/2017/09/icuguidebook.pdf

The below describes the difference between ward-based care, HDU and ICU In hospitals, based on three levels:

• Level one - ward-based care: Patients do not require organ support (for example, they may need an IV drip or oxygen mask) 
• Level two - high dependency unit (HDU): Patients need single organ support (excluding mechanical ventilation) such as renal haemofiltration or inotropes and invasive BP monitoring. They are staffed with one nurse for every two patients
• Level three - intensive care unit (ICU): Patients require support for two or more organs (or need mechanical ventilation alone). They are staffed with one nurse per patient and usually with a doctor present in the unit 24 hours a day

The NHS has different levels of critical care, based on the clinical needs of patients.

• Level 0 – patients whose needs can be met through normal ward care in an acute hospital.
• Level 1 critical care – patients at risk of their condition deteriorating or those recently relocated from higher levels of care, whose needs can be met on an acute ward with additional advice and support from the critical care team.  
• Level 2 critical care – patients requiring more detailed observation or intervention, including support for a single failing organ system or post-operative care and those ‘stepping down’ from higher levels of care. Also known as ‘high dependency units’ (HDUs).
• Level 3 critical care – patients requiring advanced respiratory support alone or basic respiratory support together with support of at least two organ systems. This level includes all complex patients requiring support for multi-organ failure. Also known as ‘intensive care units’ (ICUs) or ‘intensive treatment/therapy units’ (ITUs).

CCU is sometimes used as the umbrella term for both level-3 (ICU) and level-2 (HDU) services. The majority (73 per cent) of CCUs are configured to use a mix of level-2 and level-3 beds flexibly, with a minority of units configured specifically for only level-2 beds or only level-3 beds (see Figure 1). Some CCUs specialise in providing care for particular clinical conditions, such as coronary CCUs for patients with severe heart problems.