Polypnea is an increase in the respiratory rate associated with a decrease in the volume of inspired and expired air. With multiple causes, this breathing disorder usually results in a feeling of shortness of breath.

Polypnea is a respiratory disorder characterized by:

• increased respiratory rate, that is, an increase in the number of respiratory cycles (inspiration and expiration) per minute;
• decreased range of breathing movements, which results in a decrease in the tidal volume, that is to say a decrease in the volume of inhaled and exhaled air.

Polypnea, rapid breathing

Polypnea is manifested by difficulty in breathing with a feeling of shortness of breath. The respiratory rate increases, which results in rapid breathing.

In adults, the respiratory rate is considered too rapid when it is greater than 20 cycles per minute.

In young children, the respiratory rate is higher than in adults. An abnormal increase in respiratory rate is seen when it is:

• greater than 60 cycles per minute, in infants less than 2 months;
• greater than 50 cycles per minute, in children between 2 and 12 months;
• greater than 40 cycles per minute, in children between 1 and 3 years old;
• greater than 30 cycles per minute, in children between 3 and 5 years old;
• greater than 20 cycles per minute, in children from 5 years old.

Polypnea, shallow breathing

Polypnea is sometimes defined as rapid, shallow breathing to distinguish it from tachypnea, which is more associated with rapid, deep breathing. During polypnea, breathing is said to be shallow because it can lead to alveolar hypoventilation, a decrease in the volume of air entering the lungs per minute. Conversely, tachypnea is characterized by an increase in the volume of air entering the lungs.

Polypnea is often the consequence of a pathology of pulmonary or cardiac origin. Among the identified causes include:

• thepulmonary embolism, which is characterized by blockage of one or more arteries supplying the lungs, usually caused by a blood clot;
• la pneumonia, an acute respiratory infection of the lungs, which is often of bacterial or viral origin;
• la bronchiolitis, a form of viral infection of the lower respiratory tract;
• theangina pectoris, also called angina, which is characterized by a deep pain in the middle of the chest and which is a sign of a cardiovascular disorder;
• themyocardial infarction, a complication of angina that results in the destruction of part of the heart muscle.

The consequences and the course of polypnea depend on various parameters including its origin. In some cases, this breathing disorder can be alleviated with adequate medical treatment. In other cases, alveolar hypoventilation due to polypnea can lead to serious complications. Emergency medical care is particularly essential in the event of acute respiratory distress.

The management of polypnea depends on the diagnosis made by healthcare professionals. Confirmed by a general practitioner, a pulmonologist, or a cardiologist, the diagnosis makes it possible to direct medical care towards:

• drug treatment, especially in cases of respiratory tract infection;
• artificial ventilation, in the most serious cases.

When artificial ventilation is considered, two solutions can be implemented:

• non-invasive mechanical ventilation, which consists in applying a helmet or a face mask, nasal or nasal-oral, to restore normal breathing to patients with moderate polypnea;
• invasive artificial ventilation, which consists of introducing a tracheal intubation tube, either nasally, orally, or by surgery in the trachea (tracheostomy), in order to restore normal breathing in patients with severe polypnea.