Enter the Dead Space volume and Respiratory Rate into the calculator to determine the Dead Space Ventilation rate; this calculator can also evaluate any of the variables given the others are known.
Dead Space Ventilation Formula
The following formula is used to calculate the Dead Space Ventilation (DSV) rate:
DSV = (Vd * RR) / 1000
Variables:
- DSV is the Dead Space Ventilation rate
- Vd is the Dead Space volume in milliliters (ml)
- RR is the Respiratory Rate in breaths per minute (bpm)
To calculate the Dead Space Ventilation rate, multiply the Dead Space volume (Vd) by the Respiratory Rate (RR), then divide the result by 1000.
What is a Dead Space Ventilation?
Dead Space Ventilation refers to the portion of each breath that does not participate in the gas exchange process because it either remains in the conducting airways or reaches alveoli that are not perfused or poorly perfused. In other words, it is the volume of air that is inhaled that does not take part in the gas exchange, either because it remains in the conducting airways or reaches alveoli that are not perfused or poorly perfused. This is because not all the air in each breath is able to reach the alveolar sacs where gas exchange occurs. Some of it fills the bronchi and bronchioles, and is left over after exhalation. This leftover air is known as the dead space volume. In healthy individuals, the dead space volume is relatively small and has little impact on overall gas exchange. However, in individuals with lung disease, dead space volume can increase, which can lead to inadequate oxygen supply to the body’s tissues.
How to Calculate Dead Space Ventilation?
The following steps outline how to calculate the Dead Space Ventilation.
- First, determine the tidal volume (Vt) in milliliters (mL).
- Next, determine the respiratory rate (RR) in breaths per minute (bpm).
- Next, determine the dead space volume (Vd) in milliliters (mL).
- Finally, calculate the Dead Space Ventilation (Vd/Vt) using the formula Vd/Vt = Vd / Vt.
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
Tidal volume (Vt) = 500 mL
Respiratory rate (RR) = 12 bpm
Dead space volume (Vd) = 150 mL
