Wedding & Gylys (2005) define Atelectasis disease as a condition brought about by inadequate gaseous exchange within the alveoli. This condition is said to arise from fluid consolidation or alveolar collapse and may wholly or partially affect one lung. It may generally be regarded as an unusual condition defined by the disintegration of lung tissue, inhibiting the normal respiration process (http://www.healthscout.com/ency/68/440/main.html ).
This disease is generally caused by an obstruction of the air ducts especially the bronchioles or also by external pressure exerted on the lung. There are several risk factors for developing this condition. Some of the factors include anaesthia, lung diseases, and obstruction by mucus, long bed rests with minimal position changes, shallow breathing and tumors.
Classification (Structural and Functional Changes)
Atelectasis or the airless condition of the either the whole or part of the lung may either be chronic or acute. The acute case usually characterized by airlessness arises when the lung has freshly collapsed. The chronic phase of the disease is defined by infections on the affected area, bronchiectasis/ broadening of the bronchi, scarring and a multifarious mix of airlessness.
Acute Atelectasis Condition
The acute condition of the disease is a regular post-operation condition, usually after abdominal or chest surgery. The mild form of the disease may also result from chest injuries, e.g. due to accidents and stabbing. Post operative / massive atelectasis often involves most alveoli in either one or more parts of the lung. In such circumstances, the level of collapse and disintegration among the alveoli are likely to be complete and consistent.
Large sedative/opiod doses, tight bandages, abdominal or chest pain, body immobility, distention (abdominal swelling) may increase the risk associated with spontaneous or post-operative atelectasis. For acute conditions resulting from a deficiency or ineffectiveness of a surfactant, the extent of damage caused to the collapsing alveoli is irregular. Such conditions resulting from such causes may either be pronounced through out the two lungs or be restricted to one part of the lung. Neonatal respiratory distress syndrome is in most circumstances common to premature babies, with inborn surfactant deficiency. Excessive use of mechanical ventilators, oxygen therapy, and associated biomedical instrumentation is regarded as a common cause of acute atelectasis to adults.
Chronic Atelectasis Condition
This condition may manifest itself in either of the two forms namely, rounded atelectasis or mid-lobe syndrome. In mid-lobe syndrome, pressure exerted on the bronchus from tumors and/or enlarged lymphatic glands causes the contraction of the central lobe of the right lung. Bronchiectasis, scarring, and/or chronic inflammation may result from pneumonia caused by the obstruction of the contracted lung (Gary, 2002).
In rounded condition of atelectasis, an external portion of the lung gradually collapses due to shrinkage and scarring of the pleura. This appears as a rounded image on the X-rays and may be mistaken as a tumor. This condition is in most cases is a complication resulting from pleural thickening, chronic scarring and asbestos-induced pleural disease.
Absorption Atelectasis
Exchange of oxygen takes place at the alveoli-duct membrane, the alveoli inflation state is caused by nitrogen which is occupies a major fraction of atmospheric air inhaled. The atmosphere is made up of approximately 20% oxygen and 78% nitrogen. If a huge amount of nitrogen within the lungs is substituted by oxygen, the volume of this new gas is subsequently reduced due to absorption by blood, leading to alveolar collapse generally referred to as absorption atelectasis (Gary, 2002).
Symptoms
At the early stages of the disease, the main symptom is abrupt blockading of the bronchus, accompanied by cyanosis and dyspnea, shock, increase in body temperature and a fall in blood pressure (Gary, 2002). At advanced stages of the disease, the pronounced or most notable symptom experienced by the patient is general body weakness and gradual development of dyspnea/ breathing difficulties (http://www.healthscout.com/ency/68/440/main.html ).
Other general signs and symptoms of Alectatasis include mild coughs, chest pain, pleural effusion, increased heart rate, cyanosis, and to some extent body fever (Gary, 2002).
Diagnosis
The condition is diagnosed through clinical examination by the close monitoring of the chest X-ray and post-operative medical course. The diagnosis may also be conducted using bronchoscopy and computed tomography (http://www.healthscout.com/ency/68/440/main.html). Close examination of the radiographic X-ray image will clearly depict the affected part of the lung /area of collapse with a shadow. In situations where the whole lobe is infected, the image will portray the mediastinum, heart and trachea deviated towards the affected area of collapse, with the diaphragm raised on that side. The diagnostic procedures may also include bronchoscopy so as to exclude foreign bodies or an obstructing neoplasm, if the cause of the condition is known (Wedding, 2005).
Treatment
Alactectasis disease is treated by combating the possible root causes of the condition. Physiotherapy is used as a post- surgical treatment of atelectasis. This method puts more emphasis on deep inhalation of air and also encourages coughing. The deep inhalation exercise may be facilitated or aided by the use of an incentive Spiro-meter. In order to enhance lung inflation, ambulation procedures may be applied in the treatment.
When dealing with patients who experience neuralgic conditions and general chest deformities, that may result in long periods defined by shallow breathing, mechanical devices may be used to boost their breathing. A common approach is the use of pneumatic medical instruments to steadily supply oxygen at regulated pressure through face masks to maintain the gaseous exchange process in the alveoli. The use of sophisticated medical instruments to achieve this is quite helpful based on the fact that partially- inflated lungs are easily expandable when compared to collapsed alveoli (http://www.merck.com/mmhe/sec04/ch048a.html). To some extend, treatment may involve use of mechanical ventilators to provide respiratory support.
When treating acute considerable atelectasis, bronchoscopy may be used to expel or forcefully remove a blockage that cannot be driven out through suctioning the air paths or coughing. For an infection or chronic atelectasis, antibiotics are prescribed. In other scenarios, treatment of atelectasis may require surgical operations whereby parts badly affected by the conition are removed especially when the disease is characterized by excessive bleeding and/or recurring infections. In cases where the obstruction is caused by tumors and growths within the airway, the situation may be dealt with through surgery, chemotherapy, radiation therapy or laser therapy. These medical procedures end up deterring further progress of both the disease and obstructive pneumonia (http://www.merck.com/mmhe/sec04/ch048/ch048a.html )
In newborns, atelectasis is dealt with through suctioning of the trachea in order to establish open airways, and in turn achieve positive pressure breathing and oxygen administration (http://www.healthcout.com/ency/68/440/main.html). High oxygen concentration administered over an extended period may promote the disease resulting in retrolental fibroplasias, common to premature infants.
Prognosis
If this condition is caused by an inhaled foreign body or a thick mucus plug, expulsion of the obstacle leads to total recovery on the part of the patient. If the state is as a result of a tumor or growth, the outcome is highly dependent on the type of growth involved. For atelectasis condition resulting from surgery, additional post-operative complications and/or conditions greatly affect the prognosis (Larson, 2006).
Conclusion
This disease / pulmonary complication are prevalent to individuals following upper abdominal and thoracic procedures. Surgical manipulation and general anesthesia lead to the condition by weakening surfactant activity and causing diaphragmatic failures (Madappa, 2009). The mortality resulting from this condition is highly dependent on the root causes of the disease on a particular patient. The disease has no racial or sexual predilection. The average age of individuals reported to have rounded atelectasis is sixty years (Madappa, 2009). The disease should therefore be treated as early as possible before it develops further. Surgical operations are encouraged at an advanced stage of the disease, especially if the underlying cause is tumors.
