<prompt> True about endotracheal intubation is -It reduces normal anatomical dead spaceIt produces decrease in resistance to respirationSubglottic edema is most common complicationAll of the above  <response>: Ans- A It reduces normal anatomical dead space 1. Endotracheal intubation decreases the normal anatomical dead space 150 ml to as less as 25 ml, thus decreases the work of breathing WOB. 2. It increases the resistance during respiration. To keep this resistance at a minimum, WIDEST INTERNAL DIAMETER ENDOTRACHEAL TUBE that will fill in the larynx is recommended. 3. The most common complication of endotracheal intubation is apnoea . 