Atelectasis

Definition

Definition of Atelectasis
Atelectasis is defined as the collapse or closure of alveoli resulting in reduced or absent gas exchange. It may affect part or all of one lung. It is a condition where the alveoli are deflated, as distinct from pulmonary consolidation.

Symptoms

Symptoms of Atelectasis

1. Cough, but not prominent
2. chest pain
3. breathing difficulty
4. low oxygen saturation
5. pleural effusion (transudate type)
6. cyanosis (late sign)
7. increased heart rate
8. low-grade fever

Causes

Causes of Atelectasis
The most common cause is post-surgical atelectasis, characterized by splinting, i.e. restricted breathing after abdominal surgery. Smokers and the elderly are at an increased risk. Outside of this context, atelectasis implies some blockage of a bronchiole or bronchus, which can be within the airway (foreign body, mucus plug), from the wall (tumor, usually squamous cell carcinoma) or compressing from the outside (tumor, lymph node, tubercle). Another cause is poor surfactant spreading during inspiration, causing the surface tension to be at its highest which tends to collapse smaller alveoli. Atelectasis may also occur during suction, as along with sputum, air is withdrawn from the lungs. There are several types of atelectasis according to their underlying mechanisms or the distribution of alveolar collapse; resorption, compression, microatelectasis and contraction atelectasis.

Diagnosis

Diagnosis of Atelectasis

1. Bronchoscopy
2. Chest CT scan
3. Chest x-ray

Treatment

Treatment of Atelectasis
The goal of treatment is to re-expand the collapsed lung tissue. If fluid is putting pressure on the lung, removing the fluid may allow the lung to expand.

The following are treatments for atelectasis:

1. Clap (percussion) on the chest to loosen mucus plugs in the airway
2. Perform deep breathing exercises (with the help of incentive spirometry devices)
3. Remove or relieve any blockage by bronchoscopy or another procedure.
4. Tilt the person so the head is lower than the chest (called postural drainage). This allows mucus to drain more easily.
5. Treat a tumor or other condition, if there is one
6. Turn the person to lie on the healthy side, allowing the collapsed area of lung to re-expand
7. Use aerosolized respiratory treatments (inhaled medications) to open the airway
8. Use other devices that help increase positive pressure in the airways and clear fluids (positive and expiratory pressure [PEP] devices)

Prognosis

Prognosis of Atelectasis
In an adult, atelectasis in a small area of the lung is usually not life threatening. The rest of the lung can make up for the collapsed area, bringing in enough oxygen for the body to function.

Large areas of atelectases may be life threatening, especially in a baby or small child, or someone who has another lung disease or illness.

The collapsed lung usually reinflates slowly if the blockage of the airway has been removed. However, some scarring or damage may remain.

Prevention

Prevention of Atelectasis

1. Encourage movement and deep breathing in anyone who is bedridden for long periods.
2. Keep small objects out of the reach of young children.
3. Maintain deep breathing after anesthesia.