Page 116 - Flexible Robotics in Medicine

102 Chapter 5

neck surgeries where tracheostomy can provide or improve surgical access and facilitate
ventilation.”

Tracheostomies can be categorized as surgical or open tracheostomy (OT) or percutaneous
tracheostomy (PT). The OT procedure, described by Durbin [1,2], creates an opening through
several dissections. After preparing the subject, an incision (either vertical or horizontal) of
2 3 cm in length is created. Following this, incisions are made in the platysma muscle,
submuscular tissues, and thyroid isthmus in that order. Lastly, the tracheal portal can be created
by two methods, either by removing the anterior part of one tracheal ring or by creating a flap
with a severed part of the tracheal ring. The PT procedure, described by Durbin [1,2],isa
simpler and less expensive method commonly used for critical subjects. This procedure does
not require the use of a surgical theater or general anesthesia. However, the subject needs to be
“already intubated and mechanically ventilated” with an endotracheal tube. A guided wire is
inserted into the trachea after an incision, and a series of dilators are then inserted into the
trachea wall over the wire until it can accommodate the size of the tracheostomy tube.

Although OT is often performed to reduce procedural complications [3], PT has become a
popular technique as it is considered a minimally invasive surgery (MIS) [4]. According to
Grey et al. [5], PT is usually preferred over OT for a variety of reasons. First, a standard PT
procedure only takes about 15 minutes at the bedside, while an OT takes about 30 minutes.
Second, subjects are able to undergo both PT and surgery on the same day, whereas subjects
who receive an OT procedure need to wait a few days before they can undergo surgery. Third,
PT reduces the opportunity for tissue reaction and infections due to the ability to utilize the
smallest tracheostomy tube size and stoma size, thus reducing tissue exposure.

The goal of this study is to develop a tracheostomy technique and device that will perform
the procedure by drilling through the trachea out to the skin. It mimics the use of a
bronchoscope, which is a tool used in PT procedures to keep the subject ventilated.

5.1.2 Unmet needs

As the device developed in this study will be minimally invasive, this section will
illuminate the unmet needs of the current minimally invasive technique, which is PT. PT
may be a popular technique, but there are limitations and complications that arise from this
procedure. Although PT poses lesser risk factors than OT, it is still considered a risky
procedure and may cause life-threatening complications. The focus will be on the technique
of creating a stoma and will not include the insertion of the tracheostomy tube. The location
of puncture of the needle is usually estimated by palpating the neck area. A landmark is a
cricoid cartilage. As such, not all subjects are able to undergo PT. These include subjects
who are obese, or have cervical spine injuries, deformities in an airway, past surgical scars
from tracheostomy or sternotomy, neck edema, or presence of neck tumors [5].