What is the minute ventilation for a 180-lb (82-kg) patient with VA 6.1 L and a respiratory rate of 10?

To determine the minute ventilation, we use the formula:

Minute Ventilation (VE) = Tidal Volume (VT) x Respiratory Rate (f).

In this instance, the problem provides the minute alveolar ventilation (VA), which represents the volume of air that reaches the alveoli per minute. However, the question is asking for minute ventilation rather than alveolar ventilation.

Since the provided information indicates VA rather than VT, we need to first recognize that minute ventilation can also be thought of as related to total ventilation, which takes into account the dead space ventilation as well. Typically, a relationship is established depending on tidal volume and respiratory rate.

Given the respiratory rate of 10 breaths per minute, the calculation becomes:

VA = Tidal Volume (VT) - Dead Space (VD)

If we have VA equal to 6.1 L, it clarifies we need to substitute into the minute ventilation formula, considering the total ventilation will be enhanced by adding the contribution of the dead space.

For a patient whose tidal volume is such that larger volumes reach the alveoli and we can assume that dead space is relatively small compared to total ventilation, we can estimate:

Minute Ventilation (VE) = VA + Dead Space, where Total