<prompt> Tracheostomy reduces dead space byBy-passing upper airwayIncreased VQ ratioReducing airflow resistanceBy all of the above mechanisms  <response>: Impoant effects of tracheostomy on respiratory physiologyTracheostomy decreases dead space as upper airways and nasal cavity are bypassedTracheostomy decreases ventilationperfusion VQ ratio. Increased dead space increases ventilationperfusion ratio as the dead space containing air is ventilated but not perfused for gaseous exchange. Tracheostomy decreased the dead space, therefore it will decrease the VQ ratioTracheostomy reduces the airflow resistanceRefer: Morgan and Mikhails Clinical Anaesthesiology, 5th edition, pg no. 1237 