Pathohistological changes of tracheal epithelium in laryngectomized patients

Abstract

Total laryngectomy results in a permanent disconnection of the upper and lower airways. Thus, the upper airways are bypassed and can no longer condition, humidify, and filter the inhaled air, leading to damage of the tracheobronchial epithelium. There is little scientific information available about the effects of tracheostoma breathing and the degree of mucosal damage in laryngectomized patients. The aims of this study were to determine the histopathologic findings and investigate the potential impact of using a heat and moisture exchanger (HME) on the tracheal epithelium in long-term tracheostomy patients. Tracheal mucosal biopsies were taken from a total of 70 patients. Specimens were stained with hematoxylin and eosin and examined by a light microscope. Normal pseudostratified ciliated columnar epithelium was found in only 9 (12.9%) cases; while, 17 (24.3%) cases had some degree of basal cell hyperplasia. Squamous metaplasia was the most common finding (50%). Pre-invasive lesions (mild and moderate squamous dysplasia) were found in only one patient who used an HME, and in eight (11.4%) non-users. Although the HME cannot completely restore the physiological functions of the upper respiratory track, it delivers a better quality of air to the lower airways and has a positive effect on tracheal mucosa.

Heat and moisture exchanger cassettes: Results of a quality/safety initiative to reduce postoperative mucus plugging after total laryngectomy

“…While pulmonary comorbidities, sex, TL type, TL extent, and performance status had no effect on MP, 4,5,11,12 Age is also a known risk factor for reduced MCC, due to a natural decline in respiratory ciliary cell function. [22][23][24][25] Increased coughing and forced expectoration are hallmarks of mucociliary dysfunction and are common respiratory symptoms following TL.…”

“…5,9,10 Breathing through an HME has a protective effect on tracheal epithelium and ciliary cells thereby reducing coughing and forced expectoration when compared with breathing through an open stoma or with ETH. [11][12][13][14][15][16]20 HMEs may perform better than ETH at preserving MCC because it more closely approximates the functions of the upper airway; providing not only humidity but also warmth, inspiratory resistance, and particle filtering. 15 Whether one or all of these additional elements contribute to improve MCC is unclear.…”

“…While pulmonary comorbidities, sex, TL type, TL extent, and performance status had no effect on MP, probability modeling found that both ETH and increasing age elevate the risk for MP. Previous studies have demonstrated that breathing through an open stoma is associated with tracheal ciliary cell death and impaired MCC 4,5,11,12 . Age is also a known risk factor for reduced MCC, due to a natural decline in respiratory ciliary cell function 22‐25 .…”

“…Upon inhalation, the air is conditioned as it passes through the warm, moist filter. HMEs have a protective effect on tracheal ciliated cells and MCC 11,12 and reduce respiratory symptoms in patients following total laryngectomy 10,13‐16 . In addition to humidification, HMEs provide resistance to airflow and remove some particulate matter 15,17 .…”

Tracheostomy in children: Epidemiology and clinical outcomes

“…The tracheostomy bypasses the defensive filtering systems of the upper airway and results in direct communication between lower airways and the ambient environment. Tracheotomy also alters mucociliary clearance mechanisms by inducing the surrounding epithelium to change from ciliated columnar to squamous . The tracheostomy tube itself can be a nidus for colonization and subsequent infection, primarily due to formation of biofilms that are particularly difficult to eradicate, even with extensive cleaning .…”