Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Job Classification

In most duration tables, five job classifications are displayed. These job classifications are based on the amount of physical effort required to perform the work. The classifications correspond to the Strength Factor classifications described in the United States Department of Labor's Dictionary of Occupational Titles. The following definitions are quoted directly from that publication.

Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Lung Collapse


Related Terms

  • Atelectasis
  • Middle Lobe Syndrome
  • Pneumothorax

Differential Diagnosis

Specialists

  • General Surgeon
  • Internal Medicine Physician
  • Pulmonologist
  • Thoracic Surgeon

Comorbid Conditions

  • AIDS
  • Chronic lung disease
  • Chronic obstructive pulmonary disorder (COPD)
  • Diabetes
  • Malnutrition
  • Neuromuscular diseases
  • Obesity
  • Pleural effusion
  • Pneumonia
  • Pneumothorax

Factors Influencing Duration

Duration of disability depends on the underlying cause of the collapsed lung tissue, whether the collapse was partial or complete, the severity of symptoms, the type of treatment, the individual's response to treatment, the condition of the other lung, or any complications.

Disability from lung collapse caused by pneumothorax is determined by the ease with which the lung is reexpanded and the treatment time required for safe removal of the chest tube.

Lung collapse related to malignancy may require surgery, chemotherapy and radiation, resulting in prolonged disability.

Recurrence of lung collapse due to pneumothorax may cause lengthy disability and may require surgery.

Medical Codes

ICD-9-CM:
518.0 - Lung Collapse; Atelectasis; Collapse of Lung; Middle Lobe Syndrome

Overview

Lung collapse (atelectasis) describes the collapse of part or all of a lung. The collapse may be due to blockages occurring in the larger or smaller air passages (trachea, bronchi, or bronchioles) or from the diminished capacity of the lung's tiny air chambers, the alveolar sacs. The lung has over 300 million alveolar sacs, where the exchange of oxygen and carbon dioxide occurs.

Symptoms of lung collapse will vary, then, depending on how much lung capacity is compromised. The collapse of a single alveolar sac would go unnoticed, but the blockage of a bronchial tube, occluding air from great numbers of air sacs, could be life-threatening.

There are three major reasons for lung collapse: obstruction, compromised surfactant, or compression. Obstructive atelectasis describes the blockage of air reaching the lung. It may result from an object like food getting stuck in the airway, from diseases in which mucus becomes so thick that it blocks the flow of air, or from tumors blocking the airway.

Adhesive atelectasis results from the lack of surfactant. Surfactants are critical to efficient air exchange because the alveoli are coated with water, which creates surface tension. Without surfactant to reduce that tension, air exchange becomes labored, and the small air sacs might collapse.

Compressive atelectasis originates from something pressing against the lung that forces air out of the alveoli. It may result when the area between the lungs and chest wall is occupied by a mass, air (pneumothorax), or liquid (pleural effusions).

Some specific causes of collapsed lung are blockage of the bronchi or the bronchioles from the accumulation of thick mucus plugs due to infection (chronic bronchitis) or disease (cystic fibrosis), difficulty dispersing mucus following abdominal or chest surgery (because coughing is painful), a spasm in the bronchial tubes (asthma), or a complication from general anesthesia. It may come from blockage due to an inhaled foreign object or a tumor in the lung that presses on the bronchus or even from an improperly positioned endotracheal tube. A condition called middle lobe syndrome describes a chronic form of collapsed lung caused by enlarged lymph glands pressing on the middle lobe bronchus. Collapsed lung may result from pneumothorax due to fractured ribs, a chest injury, or a penetrating wound that perforates the outer covering of the lung. Surfactant might be compromised by smoke inhalation, uremia, or cardiac bypass surgery.

Atelectasis occurs in 25% of patients having undergone abdominal surgery. Doctors see this postsurgical problem most often in the elderly, obese, or those who have respiratory disease. Usually, it is a temporary condition that resolves uneventfully.

Source: Medical Disability Advisor



Diagnosis

History: Most commonly, symptoms of partial lung collapse (segmental atelectasis) include shortness of breath and easy fatigue, with gradual onset.

Individuals with more significant lung collapse (lobar) may report sudden chest pain (especially when severe and one-sided upon inhalation), shortness of breath, chest tightness, easy fatigue, dizziness, rapid heartbeat, fever, and bluish color of the skin caused by lack of oxygen. Many individuals report that these symptoms began during rest or sleep.

Physical exam: Stethoscope examination with careful listening to breath sounds (auscultation) reveals decreased breath sounds on the side of the body with the affected lung.

Tests: A chest x-ray reveals the airless part of the lung. In the case of a pneumothorax, air will be present outside the lung. If performed, blood tests show changes in oxygen and carbon dioxide (arterial blood gases) levels in the blood. Sometimes a CT is helpful in determining the cause of lung collapse. Bronchoscopy (insertion of a bronchoscope into the lung through the mouth) is useful to inspect the interior of the tracheobronchial tree, take specimens for biopsy and culture, and remove secretions or foreign bodies.

Source: Medical Disability Advisor



Treatment

Depending on the cause, treatment will be directed toward thinning the lung secretions, eliminating or minimizing any airway obstruction or lung compression, or re-establishing surfactant production.

When collapse is caused by an accumulation of mucus, treatment may include deep breathing, coughing, chest clapping, and postural drainage (a technique using gravity to assist in drainage of lung secretions). Treatment may also include antibiotics, increased fluid intake, and the use of humidifiers or bronchodilators. If mechanical obstruction is suspected, the first measures are forced coughing, suctioning, and respiratory or physical therapy. If there is no relief, then fiberoptic bronchoscopy (a lighted viewing instrument passed down the trachea into the bronchi) helps identify and remove the obstruction. Heavy secretions can be suctioned at the time of bronchoscopy. If a foreign body is present, it can be removed at this time as well. It is rare that surgery is required to extract foreign objects.

If a pneumothorax has caused the lung collapse, the placement of a chest tube between the ribs into the pleural space allows the evacuation of air from the pleural space. With the chest tube left in place, the lung may take several days to reexpand. Hospitalization is typically required for chest tube management. Pain relievers and antibiotics are prescribed, and increased fluid intake is encouraged.

Surgery may be indicated to prevent recurrent episodes. Surgical removal of the affected area (resection) is used when the collapse is chronic due to recurrent respiratory infections or a tumor. Tumors may also be treated with radiation or chemotherapy. Laser therapy is effective in reducing obstruction in selected cases.

In the case of unresectable tumors, sometimes stents are placed to hold the airways open to prevent lung collapse.

Source: Medical Disability Advisor



Prognosis

The prognosis following treatment for lung collapse is generally good. In some cases, the collapsed lung may resolve spontaneously. However, up to 50% of afflicted individuals have a recurrence.

When the mucus plug obstructing the airway causes partial lung collapse, nonsurgical methods are most often successful in expanding the lung. If the obstruction is noncancerous (benign), the obstruction may be removed surgically or nonsurgically. After the removal, the collapsed lung usually returns gradually to its normal, inflated state. However, some residual scarring or damage may result.

If the obstruction is caused by a malignant tumor, appropriate treatment for cancer (e.g., surgery, chemotherapy, radiation) is prescribed. Prognosis depends on the extent of spread of the cancer (metastasis).

In an adult, a partially collapsed lung is not usually life-threatening because unaffected parts of the lung (or, if the whole lung is collapsed, the other lung) expand to compensate for the loss of function in the collapsed area.

Source: Medical Disability Advisor



Rehabilitation

The cause of lung collapse determines the rehabilitation required. The frequency and duration of rehabilitation may be contingent on the extent of the lung collapse at diagnosis. Collapse due to problems with secretions or mucus is handled with continued emphasis on breathing exercises and strategies for expectorating secretions (chest clapping, postural drainage). Nutritional and physical therapy may be required after treatment for lung cancer.

Source: Medical Disability Advisor



Complications

Possible complications of lung collapse include pneumonia, which can develop rapidly after partial lung collapse, lung abscess, permanent lung scars, and subsequent recurrent collapse of lung tissue.

Source: Medical Disability Advisor



Ability to Work (Return to Work Considerations)

Following recovery, special restrictions or accommodations are not usually required at the individual's workplace. Work restrictions must be determined on an individual basis if the individual returns to work before all symptoms have resolved.

Source: Medical Disability Advisor



Failure to Recover

If an individual fails to recover within the expected maximum duration period, the reader may wish to consider the following questions to better understand the specifics of an individual's medical case.

Regarding diagnosis:

  • Does individual have a history of accumulation of thick mucous plugs in the lungs, such as in chronic bronchitis or cystic fibrosis?
  • Does individual have a history of asthma?
  • Has individual undergone recent abdominal or chest surgery?
  • Did individual inhale a foreign object?
  • Is there a tumor in the lung that is pressing on the bronchus?
  • Has individual recently had trauma to the chest?
  • Does individual report sudden chest pain, especially severe and one-sided upon inhalation?
  • Does individual complain of shortness of breath, chest tightness, easy fatigue, dizziness, rapid heartbeat, fever, and bluish color of the skin?
  • Was a chest x-ray done? Did it reveal evidence of lung collapse and / or the presence of air outside the lung?
  • Were changes in oxygen and carbon dioxide levels in the blood measured (arterial blood gases or ABGs)?
  • Was CT or bronchoscopy done?
  • Was reason for the lung collapse determined?

Regarding treatment:

  • If collapse was caused by an accumulation of mucus, did individual receive chest clapping, deep breathing, coughing, and postural drainage?
  • Were antibiotics or pain medications required? If so, was individual compliant with the medication regimen?
  • Is individual increasing fluid intake?
  • If there was no relief, was fiberoptic bronchoscopy done?
  • Was obstruction removed or suctioned?
  • If lung collapse was caused by pneumothorax, was individual hospitalized for chest tube placement to re-expand the lung?
  • Was surgery required to prevent recurrent episodes if collapse is chronic due to recurrent respiratory infections or a tumor?
  • If due to a tumor, is treatment with radiation or chemotherapy also recommended?
  • If the tumor cannot be removed (resected), is placement of a stent to hold the airways open recommended?

Regarding prognosis:

  • Is this the first collapsed lung individual has had, or is this a recurrence?
  • If surgical removal was required, how much lung was removed?
  • Is there residual scarring or lung damage? If so, how extensive is the scarring, and what type of damage occurred?
  • If a malignant tumor caused the collapse, has the cancer spread (metastasized)? To what extent?
  • Has individual developed complications such as pneumonia or lung abscess? If so, how was the complication treated, and what was the outcome?

Source: Medical Disability Advisor



References

General

Schwartz, Seymour, ed. Principles of Surgery. New York City: McGraw-Hill, 1999.

Source: Medical Disability Advisor






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