Devices for maintaining patency of surgically created channels in tissue

Abstract

Devices and methods for altering gaseous flow within a lung to improve the expiration cycle of an individual, particularly individuals having chronic obstructive pulmonary disease. The methods and devices create channels in lung tissue and maintain the patency of these surgically created channels in tissue. Maintaining the patency of the channels allows air to pass directly out of the lung tissue which facilitates the exchange of oxygen ultimately into the blood and / or decompresses hyper-inflated lungs.

Description

REFERENCE TO RELATED APPLICATION [0001] This is a continuation-in-part application of U.S. application Ser. No. 60 / 488,332 filed on Jul. 18, 2003.FIELD OF THE INVENTION [0002] This is directed to methods and devices for altering gaseous flow within a lung to improve the expiration cycle of an individual, particularly individuals having chronic obstructive pulmonary disease. The methods and devices create channels in lung tissue and maintain the patency of these surgically created channels in tissue. Maintaining the patency of the channels allows air to pass directly out of the lung tissue which facilitates the exchange of oxygen ultimately into the blood and / or decompresses hyper-inflated lungs. BACKGROUND OF THE INVENTION [0003] The American Lung Association (ALA) estimates that nearly 16 million Americans suffer from chronic obstructive pulmonary disease (COPD) which includes diseases such as chronic bronchitis, emphysema, and some types of asthma. The ALA estimated that COPD was ...

AI Technical Summary

Benefits of technology

This approach allows for improved gas exchange and decompression of hyper-inflated lungs, providing a more effective treatment for COPD by maintaining the patency of collateral channels, which is not achieved by existing treatments.

Problems solved by technology

Those inflicted with COPD face disabilities due to the limited pulmonary functions.

Usually, individuals afflicted by COPD also face loss in muscle strength and an inability to perform common daily activities.

Since the damage to the lungs is irreversible, there is little hope of recovery.

Most times, the physician cannot reverse the effects of the disease but can only offer treatment and advice to halt the progression of the disease.

However, these conducting airways do not take part in gas exchange because they do not contain alveoli.

As a result, the lungs cannot evacuate all of the inspired air.

The destruction of the alveolar walls results in a dual problem of reduction of elastic recoil and the loss of tethering of the airways.

Unfortunately for the individual suffering from emphysema, these two problems combine to result in extreme hyperinflation (air trapping) of the lung and an inability of the person to exhale.

In this situation, the individual will be debilitated since the lungs are unable to perform gas exchange at a satisfactory rate.

While alveolar wall destruction decreases resistance to collateral ventilation, the resulting increased collateral ventilation does not benefit the individual since air is still unable to flow into and out of the lungs.

Yet, bronchodilator drugs are only effective for a short period of time and require repeated application.

Moreover, the bronchodilator drugs are only effective in a certain percentage of the population of those diagnosed with COPD.

Unfortunately, aside from the impracticalities of needing to maintain and transport a source of oxygen for everyday activities, the oxygen is only partially functional and does not eliminate the effects of the COPD.

Moreover, patients requiring a supplemental source of oxygen are usually never able to return to functioning without the oxygen.

However, lung reduction surgery is an extremely traumatic procedure which involves opening the chest and thoracic cavity to remove a portion of the lung.

If the entire lung is emphysematous, however, removal of a portion of the lung removes gas exchanging alveolar surfaces, reducing the overall efficiency of the lung.

Lung volume reduction surgery is thus not a practical solution for treatment of emphysema where the entire lung is diseased.

Both bronchodilator drugs and lung reduction surgery fail to capitalize on the increased collateral ventilation taking place in the diseased lung.

The body's natural healing response sets into motion, amongst other things, cell proliferation which can result in a build-up of scar tissue.

Drug eluting coronary-type stents are not known to overcome the above mentioned events because these stents are often substantially cylindrical (or otherwise have a shape that conforms to the shape of a tubular blood vessel).

Hence, they may slide and eject from surgically created openings in an airway wall leading to rapid closure of any channel.

Not surprisingly, experiments in animal models found that placement of a paclitaxel drug eluting vascular stent into the opening did not yield positive results in maintaining the patency of the opening.

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