The trachea is composed of 35–45 cartilaginous C-shaped rings that are connected by muscle, mucosa, ligaments, and connective tissue. This creates a flexible structure that connects from the larynx to the bronchi to deliver air and transport debris to the larynx through coughing. Trauma is often the primary cause of tracheal injury and injuries to the trachea, for example a tracheal tear from a dog fight can result in a leak into the subcutaneous tissue surrounding this structure, causing subcutaneous emphysema over the cervical and thoracic areas.

A temporary tracheostomy tube is a device placed in the trachea, between the tracheal rings, through a surgical opening called a tracheotomy. The most common indication for TT placement is upper airway obstruction, often due to brachycephalic airway disease or laryngeal paralysis or neoplasia. Disease processes such as upper airway swelling, inflammation, trauma, neoplasia, or laryngeal paralysis can all be indications for tracheostomy tube placement. Often conditions such as laryngeal paralysis may be manageable with sedation alone, however, if the patient has severe dyspnoea, hypoxaemia, or hypercapnia despite sedation and supplemental oxygen therapy, then an endotracheal (ET) or TTs may be placed.

Tracheostomy tubes may be indicated during intraoral procedures which carry risk of swelling/inflammation. Patients with tracheostomy tubes should be monitored 24 hours a day, as an obstruction can occur at any time. They should also be avoided, if possible, in very small animals due to increased risk of complications.

Tracheostomy Placement/Choosing a Tracheostomy Tube

Patients should ideally be anaesthetised or heavily sedated. In emergency situations, however, anaesthesia may not be possible. Patients are placed in dorsal recumbency with a towel, foam wedge, or sandbag beneath the neck. The head should be secured, and front legs fixed caudally to ensure the surgical site remains still during the procedure and the area from the larynx to the eighth tracheal ring is clipped and surgically prepared.

There are several types of tracheostomy tubes available. Tracheostomy tubes are much shorter than endotracheal tubes and they need to be soft and pliable. An appropriate size tube needs to be 6 or 7 tracheal rings in length and have a maximum diameter of 50% of the diameter of the tracheal lumen. Larger tubes will often come with an inner cannula, whereas smaller tubes will not have these. An advantage of the inner tube is the ability to intermittently clean/change to prevent mucus build up. A tracheostomy tube can be made from an ET tube.

The tubes come in sizes ranging from an inner diameter of 3–12 mm. The outer diameter of the tube should be the right size not to cause trauma but have an inner diameter large enough to minimise any obstructions. Smaller tubes with a 4-mm inner diameter or less, are only sold as single cannulas that do not have a cuff. Tubes with an inner cannula allow replacement of the inner cannula without removal of the entire tube, as well as allowing for removal of the inner cannula to clean, allowing the outer cannula to stay in place.

When performing mechanical positive pressure ventilation, a cuffed tube is necessary. Uncuffed tracheostomy tubes are used after anaesthesia and are also indicated when the patient is being weaned from the tracheostomy. An uncuffed tube should be used ordinarily, as it is less traumatic and less likely to accumulate secretions.

Tracheostomy Care

Stoma Care

The stoma site for the TT is an open wound and should be treated as such. Ensure that the site is visualised at least twice a day, to avoid any dehiscence or necrosis from developing. Cleaning of the stoma site should occur as following:

• Use gauze squares with 2% chlorhexidine scrub diluted 1:1 with water.
• If needed, gently clean the tender tissues inside the stoma with sterile cotton swabs moistened with sterile saline.
• Do not allow any ointments or scrub to contact tissues inside the incision.

The wound shouldn’t be dressed, as the tracheal ring ties need to be easily accessible should the patient need a new tube introduced quickly. Cleaning of the stoma site should occur at a minimum of every 12 hours and the use of antimicrobial scrub solutions is discouraged. There are tube ties that ensure that the trach tube stays in place, these are easily replaced and should be if they become soiled. Some studies suggest that TT sites are more susceptible to MRSA, therefore, asepsis when performing cleaning, suctioning, and general care of the TT and stoma site is key.

Patient Care

The presence of the TT often produces a ‘foreign body’ response. This causes an inflammatory response, inflammation, and potential swelling to the tracheal lining. This response also causes an increase to the protective secretions within the lumen of the trachea. The presence of the TT introduces cold, dry air into the trachea as opposed to the warm humidified air that is provided by the upper respiratory tract (URT) in patients with a patent trachea. This can create desiccation to the trachea mucosa and as a result an increase of thicker mucoid secretions occurs. As airway secretions are 90% water, airway clearance becomes difficult if the patient is systemically dehydrated.

The risk of occlusion either through patient interference, obstruction by skin folds or by the build-up of the mucoid secretions; it is, therefore, extremely important to monitor these patients constantly for any respiratory distress, dyspnoea, or respiratory arrest and provide oxygen to the patient where necessary. Patients with TTs in place should, therefore, be located in an easily accessible, relatively quiet central area, choosing an area that is not only visible but also audible. Increased monitoring, such as continuous pulse oximetry and electrocardiography (ECG) is advisable, along with a dedicated member of staff being assigned to the patient, also alerting other staff members, allowing them to assist in observing the patient. Administering mild analgesics or anxiolytics will help to provide comfort.

Patients should have periods where nebulised air is inhaled. Previously it was thought that instilling sterile saline via the tracheostomy tube to try and help prevent the build-up of thick viscous secretions was more beneficial as it was thought that saline broke up/dissolved these secretions. However, mucous is 99% bound by disulphide bonds so the introduction of saline will not make the mucous any less viscous. Flushing with saline possibly introduces the risk of fluid entering the lungs and contributing toward an aspiration pneumonia. Humidifying or nebulising the air should prevent mucous build up due to the way it mimics the tracheal environment. If there are mucoid build-ups, change the inner cannula or the whole tube for a new, sterile one. Techniques such as coupage can instead be used to loosen those secretions and cause a transient cough. After nebulisation, coupage is performed by gentle clapping on the chest wall, which can break up debris and provoke a cough reflex. Monitor closely during this time as the TT can be inadvertently removed by forceful coughing. Walking patients’ short distances after nebulisation is an alternative to coupage, as activity will increase tidal volume, stretch the airways, and promote coughing. It is useful to have laminated instructions on how to care for the TT and another laminated document to ensure the correct equipment is kept with the patient at all times.

References

1.  Baldwin KA. Nursing care and placement of the tracheostomy tube. In: Proceedings of the North American Veterinary Conference; January 8–12, 2005; Orlando, FL.

2.  Battaglia AM, ed. Small Animal Emergency and Critical Care for Veterinary Technicians. 2nd ed. St. Louis, MO: Saunders Elsevier; 2007:260–263.

3.  Doyle E. Understanding tracheostomy tubes. The Veterinary Nurse. 2020;11(3):132–137.

4.  Henshaw V. Placement, care and maintenance of temporary tracheostomy tubes in dogs. Veterinary Nursing Journal. 2021;36(4):122–126.

5.  Kulendra N. Temporary tracheostomy tubes: a practical guide. VETcpd. https://vetcpd.co.uk/wp-content/uploads/2018/06/Temporary-tracheostomy-tubes-a-practical-guide_Preview.pdf. 5(2).

6.  Mazzaferro EM. Temporary tracheostomy. Top Companion Anim Med. 2013;28(3):74–78.

7.  McBride D. Emergency tracheostomy tube placement. In: World Small Animal Veterinary Association Congress Proceedings; September 25–28, 2017; Copenhagen, Denmark. https://beta.vin.com/members/cms/project/defaultadv1.aspx?id=8506446&pid=20539& (VIN editor: Link may not be accessible 6/26/22).

8.  Nicholson I, Baines S. Complications associated with temporary tracheostomy tubes in 42 dogs (1998 to 2007). J Small Anim Pract. 2012;53(2):108–114.

9.  Sierra L. Managing Patients with Temporary Tracheostomy Tubes. Today’s Veterinary Practice. https://todaysveterinarypractice.com/emergency-medicine-critical-care/todays-technician-managing-patients-with-temporary-tracheostomy-tubes. November/December 2012.

10.  Stordalen M, Silveira F, Fenner J, Demetriou J. Outcome of temporary tracheostomy tube-placement following surgery for brachycephalic obstructive airway syndrome in 42 dogs. J Small Anim Pract. 2020;61(5):292–299.

11.  Vygonvet.co.uk. Tracheostomy tube placement. Vygon Vet.