It’s highest in the infant at 3 ml/kg ideal body weight and is about 2 ml/kg in older children and adults. It’s called anatomic because it’s fixed by anatomy and doesn’t change.Ībout a third of each normal breath we take is anatomic dead space, which means that a third of each breath is essentially wasted. It consists of conducting airways such as the trachea, bronchi, and bronchioles -structures that don’t have alveoli. Anatomic Dead SpaceĪnatomic deadspace consists of the parts of the respiratory tract that are ventilated but not perfused. They all impact how well a patient ventilates. There are three types of dead space: anatomic, physiologic, and that dead space belonging to any airway equipment being used to assist ventilation. Dead space is the portion of the respiratory system where tidal volume doesn’t participate in gas exchange: it is ventilated but not perfused.

One important contributor to ventilation perfusion mismatch is dead space. It will help you understand how you can use these concepts to care for your patient. This article will describe how dead space is different from shunt. Physiologic dead space is ventilation of poor perfused alveoli. Shunt is perfusion of poorly ventilated alveoli.

Shunt vs dead space examples