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Modular origami joint operator to create bendable motions with multiple radii 103

5.1.2.1 Complications of percutaneous tracheostomy
The PT procedure can cause some complications, either minor or life threatening. The
complications are divided into three categories—immediate, early, and late [3]. The
complications include overshoot to the posterior tracheal wall and significant bleeding. Lack of
visualization may result in inaccuracy in needle puncture. Lack of estimation of needle
puncture may result in over puncturing or puncturing through the entire trachea, causing life-
threatening damage to the posterior tracheal wall. While small posterior wall tears can heal
without intervention, large tears may require immediate surgery or the use of stents to repair.
The puncture may damage the esophagus, which is situated posterior to the trachea.
Another complication that may arise due to the lack of visualization is significant bleeding due to
vessel erosion [5], usually occurring in the anterior jugular venous system [6]. Although bleeding
is a common complication, the source of bleeding cannot be identified without visualization.
Injuries may lead to local infections. Local infections can occur as the tracheostomy site is
continuously exposed to oral secretions, thus making it an ideal site for bacterial infections.
A serious complication that may occur following PT is tracheal stenosis, occurring at the
site of a stoma.
5.1.2.2 Current measures

The current measures taken for better visualization are the use of a fiber-optic
bronchoscope that is inserted through the endotracheal tube and used for ventilation and the
use of ultrasound to study the vasculature of the neck before performing PT.

Injuries have been reduced since the use of bronchoscopy during the PT procedure as it
allows for better visualization inside the trachea.
However, an injury that is difficult to avoid during PT is thyroid injury. While OT allows
for more precise visualization when dividing the thyroid isthmus to expose the trachea, the
PT procedure does not have the visualization of the thyroid gland, so puncture wounds to
the thyroid, often resulting in bleeding, are common [6].
Thus a solution is to use ultrasound imaging. According to Rudas et al. [7], the use of
ultrasound before PT or real-time ultrasound is essential, and it allows for better
visualization of the anatomy and vasculature of the subject’s neck. The visualizations of
these anatomical landmarks and vasculature are essential to avoid bleeding, injuries to these
tissues and cartilage, and, most importantly, to increase puncture accuracy.

5.1.3 Transoral endoscopes

State-of-the-art endoscopes like (1) Olympus LF TP, (2) Ambu aScope 4 Broncho Slim,
and (3) Pentax FI-7RBS are the commercially available bronchoscopes and tracheal