Page 424 - Flexible Robotics in Medicine

418 Chapter 19

19.1.1 Laryngeal cancer

Laryngeal cancer is a common reason for the execution of tracheostomy. Laryngeal cancer
is the cancer of the larynx that is commonly associated with smoking, which constitutes a
significant risk factor. The larynx is an organ that is associated with breathing and the
protection of the trachea from food during swallowing. In the United Kingdom, this form of
cancer has been observed to be on the rise, with more cases being observed in men. Men
from the age of 70 74 years form the largest group of patients. Laryngeal cancer could
potentially spread to nearby tissues or to the thyroid, trachea, or esophagus as well as
nearby lymph nodes, causing widespread metastasis. As a result, it is necessary in many
cases to remove the laryngeal tissue in the area, thus destroying the nearby tissue and native
airway. This necessitates tracheostomy, which is our procedure of interest.

19.1.2 Bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a disease that affects infants. It primarily affects
those that have required oxygen support in the past. BPD is essentially the chronic long-
term dependence on supplemental oxygen as a result of insufficient surfactant. The
complications that are associated with BPD often persist into adulthood. Tracheostomy is
relevant to this condition as well as other respiratory conditions because it is performed as a
means of providing support to the respiratory systems of these patients.
Tracheostomy, in general, is an increasingly standard surgical procedure performed, in
many cases on critically ill patients. There has been an observed trend toward minimally
invasive techniques, including the percutaneous tracheostomy (PT). This method has been
shown to be favorable due to ease, low cost, and a reasonable level of safety, which is
comparative if not better than the traditional open tracheostomy (OT) technique.

Tracheostomy is an opening surgically performed on patients with upper airway
obstruction. The opening is created through the neck into the trachea, allowing direct
access to the breathing tube. The OT procedure includes an incision done using an
introducer needle to perform a minimal dissection onto the pretracheal tissue, to push the
thyroid isthmus downward. A bronchoscopy is then performed, using the light reflex to
select the best site for the introducer needle such that it is directed caudad into the lumen,
avoiding the posterior tracheal wall. The J-tipped guidewire, stylet, and a dilator are then
used for tract dilation. Currently, PT has proven to be a feasible minimally invasive
alternative, as the technique uses serial dilators over a guidewire, conducted at the
bedside in intensive care units under bronchoscopy. This expedites the performance of the
procedure, without having to transport critically ill to and from the operating room.
Furthermore, the cost is roughly half that of performing OT. A single-tapered dilator is
later designed to replace serial dilators by further simplifying the technique. However,