Dyspnea, a feeling of difficulty in breathing, is a frequent symptom of respiratory and cardiac diseases in particular. It requires multiple management. 

We call “dyspnea” a feeling of difficulty in breathing (“I have trouble breathing, I lack air”). This is a subjective symptom. Its intensity is not necessarily related to the severity of the objective abnormalities in respiratory function. It is a more or less distressing sensation where physiological disturbances intervene, but also psychological reactions of the subject. A distinction should be made between acute dyspnea (sudden, rapidly worsening and requiring rapid management, such as that accompanying pulmonary edema or an asthma attack) and chronic dyspnea (onset gradually, slowly worsening ). This can occur on exertion (exertional dyspnea) and then permanently, at rest. 

Causes 

Dyspnea can be caused by numerous pathologies, respiratory (asthma, COPD, pulmonary emphysema, pulmonary fibrosis. Infections, bronchial cancers, etc.), cardiac (all causes of heart failure), neurological (all neuromuscular diseases, which are susceptible to to degrade the performance of respiratory muscles), or metabolic (obesity is a major cause of dyspnea). 

Diagnostic 

The diagnosis of dyspnea (and its cause) is made with several examinations: 

• Physical examination 
• Blood test 
• Test d’effort
• Electrocardiogram 
• Arterial gas measurement 
• Chest x-ray 
• Respiratory functional exploration
• Echocardiography…

Doctors have tools to quantify and assess chronic dyspnea. 

Dyspnea scales directly or indirectly measure dyspnea and / or its impact on daily activity.

Examples of scales used:

The Medical Research Council (MRC) scale

This scale, widely used in the monitoring of respiratory diseases, is based on the difficulty of climbing, walking or climbing stairs and makes it possible to define 4 stages of dyspnea:

• stage 0: dyspnea for sustained efforts (rise of 2 floors)
• stage 1: dyspnea when walking fast or downhill
• stage 2: dyspnea when walking on flat ground, following a person of his age
• stage 3: dyspnea forcing you to stop to catch your breath after a few minutes or a hundred meters on level ground
• stage 4: dyspnea at the slightest effort

The visual analog EVA scale

This is the simplest scale. The patient assesses his shortness of breath by placing the cursor at the desired level on a small ruler, one end of which indicates “no shortness of breath at all” and one indicates “maximum shortness of breath”. The doctor assesses the dyspnea by reading the back of the ruler.

For about ten years, multidimensional scales have been developed to give a more global assessment of dyspnea (sensory dimension but also affective dimension).

The people concerned 

Dyspnea is the most common complaint in respiratory diseases, of the obstructive or restrictive type. The main obstructive diseases that cause dyspnea are chronic obstructive pulmonary disease (COPD) and asthma. 

Dyspnea is also the most frequent reason for consultation with the cardiologist. Cardiovascular pathologies are one of the frequent causes of dyspnea. Thus, dyspnea is one of the major symptoms of heart failure. 

Dyspnea is also one of the most common symptoms at the end of life.

Risk factors 

Being overweight and sedentary as well as sleep apnea syndrome (OSAS) can cause dyspnea or worsen it.

Feelings of running out of air 

People who have dyspnea describe a feeling of lack of air, of having chest tightness, lack of air, a feeling of breathing effort, the feeling of having rapid breathing …

Clinical signs

Dyspnea may be accompanied by objective clinical signs:

• Changes in respiratory rate 
• Flapping the wings of the nose 
• Cough
• Intercostal indrawing

Treatment of dyspnea begins with treating the cause of the dyspnea. 

Chronic dyspnea requires multiple management: symptomatic treatment but also different therapeutic approaches for dyspnea (respiratory rehabilitation for example), non-pharmacological treatments (hypnosis, ventilation, etc.), non-specific treatments for dyspnea (use of low-dose opiates. doses) and psychological management, especially in cases where treatments for the cause do not work.

Not smoking helps prevent dyspnea due to chronic obstructive pulmonary disease (COPD). Dyspnea is indeed the main symptom of COPD. Avoiding overweight and being sedentary are also ways to prevent dyspnea or worsening of dyspnea.