When a catheter is placed through the skin into an anatomic structure, a certain amount of physiologic concretion usually is found to collect on the outer surface of the catheter during the period that it dwells in the body. In blood vessels, this concretion is usually fibrin or clot. In the bladder, urinary substances (uric acid, urea, blood-components, biofilm) coat the outer surface. In chest tubes, blood and fibrin material adhere to the outer surface. In the intestinal tract, biofilm and succus entericus or stool frequently form a cast on the outer surface of the tube. In the trachea, the outer surface of the tube gets coated with mucous and respiratory substances that form a cast or biofilm on the outer surface.
Thus, when such a catheter is removed from the body, some of this material is often “peeled” off of the catheter surface, and if the catheter passes through the body wall, much of this detritus is left within the anatomic structure that has been cannulated. When this is blood clot in a vessel, it can lead to clot formation with a venous embolus from a vein (usually harmless, but can lead to thrombophlebitis) or an arterial embolus, which can be more serious if it obstructs an artery downstream The GI tract can usually expel the retained material without difficulty. Clot or fibrin masses in the pleural space can be reabsorbed or cause pleural adhesions which are of little clinical consequence. Urinary debris can cause problems if over 3-4 mm in diameter if it cannot be passed via the ureter or urethra, and such catheter debris can act as a nidus for bladder stone formation. With a minitracheotomy tube, the debris falls off into the patient's trachea, where it can stimulate a coughing episode that can increase the morbidity in emphysema or chronic obstructive pulmonary disease (COPD) patients, who are the usual candidates for use of such a tube.
COPD is a slowly progressive disease of the airways that is characterized by a gradual loss of lung function. In the U.S., the term COPD includes chronic bronchitis, chronic obstructive bronchitis, or emphysema, or combinations of these conditions. It represents the fourth leading cause of death in the U.S. 12.1 million adults ages 25 and older reported being diagnosed with COPD in 2001. About 24 million adults have evidence of impaired lung function indicating that COPD is underdiagnosed. About 119,000 adults ages 25 and older died from COPD in 2000. While the COPD death rate for females more than doubled between 1980 and 2000, and the number of deaths for females surpassed the number for males in 2000, the overall age-adjusted death rate for COPD remained higher for males in 2000. The age-adjusted COPD death rate was about 46 percent higher in males than females and 63 percent higher in whites than blacks. COPD is the fourth leading cause of death in the U.S. and is projected to be the third leading cause of death for both males and females by the year 2020.
Physicians who would normally use a COPD minitracheostomy ventilation technique may avoid using the minitracheostomy tubes because of the problem of mucous plugs falling into the trachea and leading to severe coughing episodes which leave COPD patients breathless and can actually be life threatening. The consequences of such solid material falling into the trachea is analogous to the feeling we all get when we aspirate a small food particle or sip of fluid. This set of problems of retained, solid components falling into a patient's trachea, blood vessels, bladder or urinary tract has led to a need to redesign these catheters. A need exists in the art for a design of a minitracheostomy tube in the lungs or a catheter in the blood vessel, bladder or urinary tract that can be easily inserted and then removed from the patients on a regular biweekly basis without causing severe problem of mucous plugs falling into the trachea and leading to severe coughing episodes, or debris from the catheter devices causing further complications in the patient.