What term is used for the amount of air that is inspired or expired in one minute?
Minute ventilation (or respiratory minute volume or minute volume) is the volume of gas inhaled (inhaled minute volume) or exhaled (exhaled minute volume) from a person's lungs per minute. It is an important parameter in respiratory medicine due to its relationship with blood carbon dioxide levels. It can be measured with devices such as a Wright respirometer or can be calculated from other known respiratory parameters. Although minute volume can be viewed as a unit of volume, it is usually treated in practice as a flow rate (given that it represents a volume change over time). Typical units involved are (in metric) 0.5 L × 12 breaths/min = 6 L/min. Several symbols can be used to represent minute volume. They include (V̇ or V-dot) or Q (which are general symbols for flow rate), MV, and VE. Determination of minute volume[edit]Minute volume can either be measured directly or calculated from other known parameters. Measurement of minute volume[edit]Minute volume is the amount of gas inhaled or exhaled from a person's lungs in one minute. It can be measured by a Wright respirometer or other device capable of cumulatively measuring gas flow, such as mechanical ventilators. Calculation of minute volume[edit]If both tidal volume (VT) and respiratory rate (ƒ or RR) are known, minute volume can be calculated by multiplying the two values. One must also take care to consider the effect of dead space on alveolar ventilation, as seen below in "Relationship to other physiological rates". Physiological significance of minute volume[edit]Blood carbon dioxide (PaCO2) levels generally vary inversely with minute volume.[citation needed] For example, a person with increased minute volume (e.g. due to hyperventilation) should demonstrate a lower blood carbon dioxide level. The healthy human body will alter minute volume in an attempt to maintain physiologic homeostasis. A normal minute volume while resting is about 5–8 liters per minute in humans.[citation needed] Minute volume generally decreases when at rest, and increases with exercise. For example, during light activities minute volume may be around 12 litres. Riding a bicycle increases minute ventilation by a factor of 2 to 4 depending on the level of exercise involved. Minute ventilation during moderate exercise may be between 40 and 60 litres per minute.[1][2] Hyperventilation is the term for having a minute ventilation higher than physiologically appropriate. Hypoventilation describes a minute volume less than physiologically appropriate. Relationship to other physiological rates[edit]Minute volume comprises the sum of alveolar ventilation and dead space ventilation. That is: where is alveolar ventilation, and represents dead space ventilation. References[edit]
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What is the amount of air that can be inspired and expired called?Tidal volume is the volume of air normally inspired or expired in one breath without any effort. It is about 500 ml in the average human adult male.
What is the volume of air inspired or expired per minute?The volume of air inspired or exhaled by a healthy man per minute is known as tidal volume which is 500 mL. The breathing rate for a normal person is 12-15 breaths per minutes. So, a normal person inhale or exhale around 6000 to 8000 mL air per minute.
What is expired minute volume?Minute volume is the amount of gas inhaled or exhaled from a person's lungs in one minute. It can be measured by a Wright respirometer or other device capable of cumulatively measuring gas flow, such as mechanical ventilators.
What is used to measure air inspired and expired by lungs?A spirometer is an apparatus for measuring the volume of air inspired and expired by the lungs. A spirometer measures ventilation, the movement of air into and out of the lungs.
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