From the Guidelines
Atelectasis should be managed with a focus on recruitment maneuvers and higher PEEP levels to improve oxygenation and reduce mortality, as evidenced by recent studies 1.
Causes and Consequences of Atelectasis
Atelectasis is the collapse or closure of a lung or part of a lung, resulting in reduced or absent gas exchange. It occurs when the alveoli (air sacs) become deflated or filled with fluid. This condition can lead to hypoxemia, pneumonia, and respiratory failure, particularly in vulnerable patients like the elderly or those with underlying lung disease.
Treatment and Management
Treatment depends on the cause and severity but typically includes:
- Addressing the underlying condition
- Encouraging deep breathing exercises
- Incentive spirometry
- Chest physiotherapy
- Early mobilization For significant atelectasis, bronchoscopy may be necessary to remove mucus plugs. Patients should be positioned with the good lung down to improve ventilation to the affected area. Adequate pain control is essential, especially post-surgery, to enable effective deep breathing. Supplemental oxygen may be required to maintain adequate blood oxygen levels.
Recruitment Maneuvers and PEEP
Recruitment maneuvers involve transient elevations in applied airway pressures intended to open ("recruit") collapsed lung and increase the number of alveolar units participating in tidal ventilation 1. Higher PEEP levels are probably required to maintain the benefit of recruitment maneuvers, especially in severely hypoxemic patients with evidence of recruitability 1. The use of higher PEEP levels has been associated with improved oxygenation and reduced mortality in patients with moderate or severe ARDS 1.
Prevention Strategies
Prevention strategies include:
- Early ambulation after surgery
- Regular position changes for bedridden patients
- Smoking cessation These strategies can help reduce the risk of atelectasis and its associated complications.
Physiotherapy and Airway Clearance
Physiotherapy, including manual hyperinflation and airway suctioning, can assist in secretion clearance and improve oxygenation 1. However, these techniques should be used with caution, as they can also have detrimental side effects, such as hemodynamic changes and increased intracranial pressure.
From the FDA Drug Label
Acetylcysteine solution, USP is indicated as adjuvant therapy for patients with abnormal, viscid, or inspissated mucous secretions in such conditions as: ... Atelectasis due to mucous obstruction 2
- Atelectasis due to mucous obstruction is a condition for which acetylcysteine solution is indicated as adjuvant therapy.
- The drug is used to help loosen and clear abnormal, viscid, or inspissated mucous secretions.
- Acetylcysteine solution can be administered through various methods, including nebulization, direct instillation, or intratracheal catheter, to help manage atelectasis due to mucous obstruction.
From the Research
Definition and Causes of Atelectasis
- Atelectasis is a state of collapsed and non-aerated region of the lung parenchyma, which is otherwise normal 3.
- It may occur in three ways: (i) airway obstruction; (ii) compression of parenchyma by extrathoracic, intrathoracic, chest wall processes; and (iii) increased surface tension in alveoli and bronchioli 3.
Diagnosis of Atelectasis
- Chest radiographs using both the anterior-posterior and lateral projections are mandatory to document the presence of atelectasis 3.
- Differentiation from lobar consolidation may be a clinical dilemma 3.
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 3.
- Persistent mucous plugs should be removed by bronchoscopy 3.
- Positive end-expiratory pressure (PEEP) increases lung volume and protects against alveolar collapse during anesthesia 4.
- Incentive spirometry has been used to prevent atelectasis after cardio-pulmonary bypass, with some studies showing an increase in vital capacity after its use 5.
Use of Positive End-Expiratory Pressure (PEEP)
- PEEP has been shown to increase functional residual capacity and may be effective in preventing atelectasis 6, 4.
- The optimal level of PEEP to prevent anaesthesia-induced atelectasis in infants has been studied, with one trial finding that 6 cmH2O of PEEP was more effective than 3 cmH2O 7.
- Withdrawing PEEP before emergence preoxygenation does not reduce atelectasis formation after nonabdominal surgery 4.