Tracheostomy reduces dead space by -: (A) By-passing upper airway, (B) Increasing V/Q ratio, (C) Raising airflow resistance, (D) By all of the above mechanisms
Answer is A. Ans. is 'a' i.e., By-passing upper airway o Important effects of tracheostomy on respiratory physiologya) Tracheostomy decreases dead space as upper air ways and nasal cavity are bypassed.b) Tracheostomy decreases ventilation/perfusion (V/Q) ratio. Increased dead space increases ventilation/perfusion ratio as the dead space (containing air) is ventilated but not perfused for gaseous exchange. Tracheostomy decreases the dead space, therefore it will decrease the V/Q ratio.c) Tracheostomy reduces the airflow resistance