Orthopnea is respiratory discomfort when lying down, which occurs in particular at night, forcing the patient to remain seated or standing. It is most often of cardiac origin, indicating left ventricular failure which results in an accumulation of fluids in the lungs. Its management consists first of all in identifying its cause and then in treating it.

The term “orthopnea” comes from the Greek “orthos” which means straight and “pnoê” which means breathing. Orthopnea, or decubitus dyspnea, corresponds to respiratory discomfort or even shortness of breath occurring at rest, when lying on the back, which improves when sitting or standing. Occurring in particular at night, it suddenly wakes the person who is prone to it and pushes him to sleep in a sitting position, in particular by increasing the number of his pillows.

Orthopnea is caused by increased pressure in the blood vessels in the lungs. It reflects the existence of pulmonary edema, that is to say an excess of fluid in the lungs: 

• When lying down, completely flat, all the pulmonary alveoli are invaded by plasma. This is what causes respiratory discomfort;
• When sitting or standing, the accumulation of fluid occurs only in the lower part of the lungs. As a result, the alveoli of the upper pulmonary regions can maintain sufficient oxygenation at rest so that shortness of breath is weakly felt.

Orthopnea can be seen whenever there is left heart failure. It is an inability of the left ventricle to provide sufficient blood flow to meet the body’s needs, whatever the cause (mitral stenosis, dilated cardiomyopathy or even myocardial infarction) and resulting in accumulation of fluids in the tissues which then concentrate mainly in the lungs.

More rarely, orthopnea can also appear during:

• certain pulmonary diseases such as chronic obstructive pulmonary disease or COPD (chronic bronchitis or pulmonary emphysema for example), which can induce excess mucus production in the lungs;
• an asthma attack;
• epiglottitis, which is an infection of the epiglottis.

Orthopnea is actually a symptom in its own right. The severity of this can be assessed by the attending physician based on the number of pillows the patient must use for sleep.

To relieve orthopnea, it is recommended not to lie down. This is because lying down increases pressure in the upper branches of the pulmonary arteries and increases the spread of edema to all parts of the lung. On the contrary, it is about positioning yourself well to facilitate breathing, preferably in a seated position, using one or more pillows, which makes it possible to reduce venous return and free up the lungs. The patient may also have recourse to oxygen therapy, at home or in the hospital.

Once the doctor has identified the cause of the orthopnea, he can put in place an appropriate treatment.

In the case of heart failure, orthopnea can be relieved in particular by taking:

• diuretics: by increasing the volume of urine, diuretics such as furosemide or bumetanide help to eliminate or even prevent the accumulation of fluids in the lungs;
• beta-blockers such as carvedilol, bisoprolol and metoprolol, which reduce the frequency of the heartbeat and allow the heart to contract better;
• angiotensin converting enzyme (ACE) inhibitors, such as Lisinopril, Captopril, and Enalapril. These drugs, recommended for people with left heart failure, block the formation of angiotensin II, a vasoconstrictor enzyme responsible for increasing blood pressure. Thanks to their vasodilator action, taking these drugs improves blood circulation and thus reduces the strain on the heart.