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I. Specific Aims

Current tracheostomy devices have multiple parts and steps that make the procedure complicated and lead to operator error, especially when the operator is faced with diverse conditions in an emergency situation. The goal of our project is to address several concerns with current devices to provide an improved approach to a standardized cricothyrotomy kit. Our approach to the design of a new tracheostomy device aims to streamline the tracheostomy procedure by reducing the number of pieces and steps required to completely secure an airway in a patient. This new design will not only reduce the complexity of the procedure, but it will also help to remove the variability of the operator’s background and training. Therefore, the specific aims of this project are;

Specific Aim 1: Design an improved device to achieve the following performance goals:

1. Reduce the number of working pieces for device implementation, and

2. Reduce the number of steps needed by the operator for implementation by;

a. Reliably locating the incision point for the procedure on various patient sizes, and

b. Adequately securing to the neck of the patient to prevent displacement during transport.

Specific Aim 2: Fabricate device that exhibits overall functionality in order

to support testing

Specific Aim 3: Test prototype in vitro

II. Significance

A tracheotomy, sometimes used interchangeably with the term tracheostomy, is a surgical procedure which begins with an opening made in the trachea. The surgeon then inserts a tube into the opening to secure an airway in a patient with a compromised upper airway. In an emergency situation, pre-hospital healthcare providers and emergency medicine physicians do not necessarily perform a tracheotomy with the same surgical equipment. Most Advanced Life Support (ALS) units carry a tracheostomy “kit” which includes the necessary components to perform a field tracheostomy.

The tracheostomy kit contains an unassembled device to be used on patients who could not be orotracheally intubated. Reasons for failure to intubate would include, but not be limited to, extensive facial trauma, blood, debris, vomitus in the oropharynx, or bad anatomy (short, fat neck or difficultly in viewing vocal chords). Variations in the anatomy of the neck can make percutaneous dilatational tracheostomy (PDT) both difficult and hazardous. Estimating the correct length and size of tracheostomy tube has been cited as a problem with PDT. In fact, Jackson (1909) stressed the importance of choosing a tube of proper size and length especially if swelling of the neck is anticipated. Patients with a deeply lying trachea may need a long shank tube (Muhammad 336).

Current tracheostomy devices have multiple parts and steps that can cause confusion and lead to operator error. For example, one device currently on the market requires seven distinct steps. The operator must first locate and puncture the trachea midline of the sternal notch and halfway between the adam’s apple and proximal clavicle. Next, the syringe must be removed from the needle while maintaining the needle’s insertion point in the neck. Then, a wire-guide is inserted through the needle into the trachea. The needle must then be broken away by snapping the plastic housing which extends approximately 1 inch from the neck. The permanent tube must then be guided down the wire-guide into the opening in the neck and trachea. The wire guide is then removed from the neck and the permanent tube is in place. Lastly, the permanent tube is secured to the patient by tying a knot around the back of the patient’s neck with shoestring-like rope. This device requires seven steps which, in an emergency situation, can be confusing and time consuming for the operator. Furthermore, it has been noted by healthcare providers that these devices often do not stay in place. The implementation of this device requires too much precious time, and it is not even guaranteed to stay correctly placed in the patient!

To the unwary operator, even an average neck with a “normal” sized trachea located correctly midline to the sternum may cause problems during PDT. Puncture of the posterior wall of the trachea on initial needle cannulation can occur, especially if the needle is inserted perpendicular to the long axis of the trachea. Estimating the correct angle of the needle insertion is difficult to judge. A safer method involves the placement of the needle at 45 degrees to the long axis of the trachea pointing towards the thorax (Muhammad 341)

Further review of the literature on emergency cricothyrotomy (or tracheotomy) kits reveals that these kits are as accurate as the traditional surgical technique. In the Journal of Emergency Medicine, Chan et al. evaluated wire-guided cricothyrotomy kits in comparison to the standard surgical method by measuring accuracy, complications, performance time, incision length, and user preference. A group of emergency medicine attending physicians and residents were trained in both techniques, and both procedures were tested on cadavers. Overall, the wire guide kits performed equal or better than the standard surgical technique in all categories, and 14 out of 15 physicians preferred the wire guide. In Anaesthesia, Fikkers et al. compared the wire guide cricothyrotomy technique to the catheter-over-needle technique. The catheter-over-needle (48 s) was faster than the wire guide (150 s) and had a higher accuracy of position (95% vs. 85%, respectively). There was one complication with the catheter-over-needle versus five with the wire guide. Fikkers concluded that the catheter over the needle technique is easier to use and better suited for inexperienced caregivers.

III. Research Methods

Specific Aim 1: Design an improved device to achieve the following performance goals:

1. Reduce the number of working pieces for device implementation, and

2. Reduce the number of steps needed by the operator for implementation by;

a. Reliably locating the incision point for the procedure on various patient sizes, and

b. Adequately securing to the neck of the patient to prevent displacement during transport.

The first of the two-piece tracheotomy device is the individual base, or platform, that includes several unique design features. The base has a flange that is placed in the sternal notch of the patient. This is used to locate the proper incision point based on the anatomical position of the sternal notch, which is located halfway between the vocal chords and the carina, is perfectly midline, and is directly over the trachea regardless of patient condition. In addition, this device locates the artificial airway well below the vocal chords (not through the cricothyroid membrane) and reduces the risk of permanently damaging the “voicebox” of the patient. In addition, this placement prevents localized intubation in either of the branched bronchi and therefore performs a true tracheostomy. Lastly, this piece incorporates large adhesive pads that provide an airtight seal around the device after placement. All of these design features efficiently address a portion of the limitations of current devices mentioned previously.

The second piece of this device includes the permanent tube and the cutting trocar. Once the base piece has been secured, this second cutting tool is used to puncture the skin at a location of the neck determined by the base. After the skin is punctured, the permanent tube is guided down the cutting trocar shaft and firmly inserted into the newly formed stoma. At the time that the permanent tube is completely inserted into the opening, a security feature locks the permanent tube onto the secured base. The cutting trocar is then removed from the opening at which point the device has been fully implemented. The permanent tube, like currently devices, is sized to adapt to airflow devices such as a BVM (bag-valve-mask) or a jet ventilator.

All three pieces of this device will be modeled using a 3D solid-modeling program. The dimensions of the new device will be modeled after current tracheostomy devices in order to mimic the general functionality of current devices. In addition, developing this model using 3D solid modeling software will provide the precision and accuracy needed to generate a functional prototype using current technology.

Specific Aim 2: Fabricate tracheostomy device that exhibits overall functionality in order to support testing

The success of this device relies heavily on the materials of which it is comprised. The pieces of the device all interact in a very mechanical nature to the extent that the materials chosen for each piece are not random, but rather are requirements. Therefore, the success of testing (Specific Aim 3) requires that the prototype be made of strictly chosen materials. The prototype of the newly designed device will consist of a strong, rigid polymer as well as the modification of current device pieces. Specifically, pieces of current tracheostomy devices will be used and modified to meet the needed specifications.

Specific Aim 3: Test prototype in vitro

Clinical testing will be completed in a swine lab at the University of Pittsburgh Medical Center. This testing will include the participation of medical school students that will ultimately be required to use this device as a physician. These participants will attempt to implement both the new tracheostomy device and a current device. Following this, we will evaluate the effectiveness of our product relative to existing devices by surveying those participants.

IV. Literature Citations

Chan TC, Vilke GM, Bramwell KJ, Davis DP, Hamilton RS, Rosen P. “Comparison of

wire-guided cricothyrotomy versus standard surgical cricothyrotomy technique.”

J Emerg Med. 1999 Nov-Dec;17(6):957-62.

Fikkers BG, van Vugt S, van der Hoeven JG, van den Hoogen FJ, Marres HA.

“Emergency cricothyrotomy: a randomized crossover trial comparing the wire-

guided and catheter-over-needle techniques.” Anaesthesia. 2004 Oct;59(10):

1008-11.

Muhammad, Joseph Kamal, et. al. “Evaluating the neck for percutaneous dilatational

Tracheostomy.” J of Cran.-Max. Surg. (2000) 28, 336-242.

Jackson C. “Tracheostomy.” Laryngoscope 19; 285-290, 1909.

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