From the Guidelines
Atelectasis is a condition where part of the lung collapses or becomes airless due to blockage of the airways or pressure from outside the lung, occurring in roughly 90% of patients undergoing general anesthesia and potentially leading to postoperative pulmonary complications 1. Atelectasis occurs when the tiny air sacs (alveoli) in the lungs deflate or fill with fluid, preventing normal oxygen exchange. Some key factors that contribute to atelectasis include:
- Mucus plugs blocking airways
- Tumors
- Foreign objects
- External pressure from fluid, air, or swelling in the chest cavity
- Shallow breathing and reduced mobility after surgery, especially chest or abdominal procedures Symptoms of atelectasis may include:
- Shortness of breath
- Coughing
- Chest pain
- Low oxygen levels However, some cases may produce no symptoms. Treatment of atelectasis focuses on addressing the underlying cause and may include:
- Deep breathing exercises
- Incentive spirometry
- Chest physiotherapy
- Bronchoscopy to remove blockages
- Medications to treat infections or reduce inflammation Preventing atelectasis involves:
- Early mobilization after surgery
- Deep breathing exercises
- Avoiding smoking
- Prompt treatment of respiratory infections According to recent studies, individualized PEEP can prevent progressive alveolar collapse, and recruitment maneuvers can reverse alveolar collapse, but have limited benefit without sufficient PEEP 1. It is essential to note that atelectasis can range from mild to severe, with serious cases potentially leading to pneumonia or respiratory failure if left untreated. Therefore, early recognition and treatment of atelectasis are crucial to prevent postoperative pulmonary complications and improve patient outcomes 1.
From the Research
Definition of Atelectasis
- Atelectasis is a state of collapsed and non-aerated region of the lung parenchyma, which is otherwise normal 2.
- It is a pathological condition usually associated with several pulmonary and chest disorders and represents a manifestation of the underlying disease, not a disease per se.
Causes of Atelectasis
- Atelectasis may occur in three ways:
- airway obstruction
- compression of parenchyma by extrathoracic, intrathoracic, chest wall processes
- increased surface tension in alveoli and bronchioli 2.
- Mechanical ventilation and endotracheal intubation can cause airway damage and inflammation resulting in excessive mucus secretions, thereby increasing the risk of respiratory failure post extubation 3.
Diagnosis of Atelectasis
- Chest radiographs using both the anterior-posterior and lateral projections are mandatory to document the presence of atelectasis 2.
- The direct signs of atelectasis are crowded pulmonary vessels, crowded air bronchograms, and displacement of the interlobar fissures 4.
- Indirect signs of atelectasis are pulmonary opacification; elevation of the diaphragm; shift of the trachea, heart, and mediastinum; displacement of the hilus; compensatory hyperexpansion of the surrounding lung; approximation of the ribs; and shifting granulomas 4.
Types of Atelectasis
- For descriptive purposes, atelectasis can be divided into the following types: segmental, lobar, or whole lung; subsegmental; platelike, linear, or discoid; round; and generalized or diffuse 4.
- Resorption atelectasis is caused by resorption of alveolar air distal to obstructing lesions of the airways; adhesive atelectasis stems from surfactant deficiency; passive atelectasis is caused by simple pneumothorax, diaphragmatic dysfunction, or hypoventilation; compressive atelectasis is due to tension pneumothorax, space-occupying intrathoracic lesions, or abdominal distention; cicatrization atelectasis stems from pulmonary fibrosis; and gravity-dependent atelectasis is the result of gravity-dependent alterations in alveolar volume 4.
Treatment of Atelectasis
- The treatment of atelectasis varies depending on duration and severity of the causal disease from chest physiotherapy to postural drainage, bronchodilator and anti-inflammatory therapy 2.
- Bronchoscopic aspiration and lavage are the common techniques used to remove retained secretions or mucus plugs 3.
- Administration of surfactant by ultrathin bronchoscope is a new concept in the treatment of persistent neonatal pulmonary atelectasis in small size neonates 5.