Following data was obtained from a 20 year old medical student: tidal volume = 540 mL, paial pressures of CO2 in expired air & aerial blood ~ PECO2 = 20 mm Hg, PACO2 = 30 mm Hg: respiratory rate = 15/min. The alveolar ventilation would be:-: (A) 4.2 L/min, (B) 4.8 L/min, (C) 5.2 L/min, (D) 5.4 L/min
Answer is D. Alveolar ventilation = (tidal volume - dead space volume) x Respiratory rate= (540 - 180) 115 = 5.4 L/min