If a person has a tidal volume of 550 ml and breathes at a rate of 14 times per minute, what is the minute ventilation rate?

The minute ventilation rate = 7.7 Lpm

Explanation:

a) The tidal volume = 550 ml

Respiratory rate = 14 times per minute

Since minute ventilation (VE) is the total volume of gas entering (or leaving) the lung per minute, it is equal to the tidal volume (TV) multiplied by the respiratory rate (f).

This implies that Minute Ventilation = VE = TV x f

= 550 * 14

= 7,700 ml/min.

Therefore, the minute ventilation rate = 7.7 Lpm (7,700/1,000) or 7.7 liters per minute.

b) The ventilation rate is also known as the inhalation rate or breathing rate.  It is the amount of air inhaled in a specified time period. Note that at rest, a normal person moves approximately 450 ml/breath * 10 breath/min or 4500 ml/min (4.5 Lpm).