The document defines critical care units and intensive care units as specialized hospital sections that provide comprehensive care for critically ill patients. It discusses the goals, organization, staffing, and principles of critical care nursing. The levels of ICU are described from level 1 to level 3 with increasing complexity of care. Ethical principles like beneficence, non-maleficence, autonomy and justice govern critical care. Staffing includes intensive care doctors, resident doctors, intensive care nurses, and allied health professionals like respiratory therapists and physiotherapists.