Pressure-support ventilation (PSV): Spontaneous or Assisted type of ventilation that is activated by the patient itself and is supported by the ventilator. It is a commonly used method in weaning in patients with hypoxia, hypercapnia and mixed respiratory failure and is especially used in critical patients in ICU. It's advantages are: • Improved oxygenation or oxygen delivery • Better ventilation/perfusion (V/Q) matching • Reduction in overall work of breathing • Increased synchronization between the patient and ventilator • Decreased requirement for sedation • Patient exercise control over factors like inspiratory flow rate and time • Increased patient comfort • Decrease risk of cardiovascular problems