Mechanical ventilation in the term used for assisted ventilation where oxygen is supplied to the lungs by means of artificial ways. INITIAL SETTINGS FOR MECHANICAL VENTILATION Initial settings for mechanical ventilation are as follows: 1. Mode of ventilation: SIMV (Synchronized intermittent mandatory ventilation) or A/C (Assist-Control) mode 2. Tidal volume: 10-15 mL/kg (keeping in view the risk of barotrauma) 3. Respiratory rate: 8-12 breaths/min in patients without metabolic acidosis and 5-6 breaths/min in asthmatic patients 4. Supplemental oxygen therapy: FIO2 of 100% and then tritrated down afterwards 5. Inspiration-expiration ratio: Initially 1:2. 1:4 or 1:5 in obstructive airway diseases. 6. Inspiratory flow rates: 60 L/min. May be increased to 100 L/min to provide tidal volume quickly. 7. Positive end-expiratory pressure: 3-5 cm of water in normal lungs 8. Sensitivity: -1 to -2 cm of water. 9. Sighs are barely required