Train for a cricothyroidotomy with a DIY mannequin

Difficult airway scenarios can cause significant morbidity and mortality and require prompt recognition and intervention. Both the American Society of Anesthesiologists and the UK Difficult Airway Society (DAS) have published guidelines for the management of unexpected difficult intubation. Both algorithms lead to the “Cannot intubate, cannot oxygenate” (CICO) scenario where they recommend a needle or surgical cricothyroidotomy as the next step. This eventuality is rare in the practice of elective anesthesia, an estimated 0.01-2 cases per 10,000 [1], making it difficult to maintain skills and knowledge.

The context of airway management is important, the incidence of failed intubation is 1 in every 50-100 cases in the emergency room, intensive care unit (ICU) and in a pre-hospital setting [2]. A “Cannot intubate, cannot oxygenate” (CICO) situation is a nightmare for any emergency physician and critical area involving high stress and adrenaline. Although other advanced airway management options such as supraglottic devices are available, cricothyroidotomy still plays an important role and should be considered as a first approach in situations where a surgical airway is unavoidable, i.e. all those cases where mask ventilation , supraglottic devices (AML, laryngeal tube) and passive oxygenation do not lead to the desired result. When advanced airway management involved only direct laryngoscopy and mask ventilation, cricothyroidotomy was routinely used if these two techniques failed. Today, however, laryngeal masks (AML) and other supraglottic devices come to the rescue and allow you to ventilate up to 95% [3] of impossible ventilations.

In light of the data presented above, cricothyroidotomy is a skill that emergency doctors and intensivists should constantly train despite hoping never to have to practice it as, for example, pilots train in parachute jumping. Considering the invasiveness of the procedure, there is some reluctance to decide to perform the cricothyroidotomy but the evidence is clear: when a surgical airway is required it is not the procedure itself that kills the patient but rather the delay in the decision to perform it. or even not doing it. In the NAP4 audit, 60% of cricothyroidotomy attempts with a needle fail. In contrast, 100% of cricothyroidotomy surgical attempts were successful [4]. The guidelines of the DAS recommend surgical access in the anterior part of the neck (FONA) compared to needle approaches, in particular the scalpel-bougie technique [5,6].

Without the ability to train how can you be ready to perform a cricothyroidotomy? Unfortunately, we cannot practice among ourselves, cadaver labs are not so widespread and professional mannequins have a certain cost that is not always accessible to all realities, the small ones in particular. The solution? Create a mannequin at home!

How to assemble a manikin at home to train to perform the cricothyroidotomy?

I present to you my version created in the garage at home and tested by various emergency / urgent doctors and nurses together with a step by step guide to try to create your own CricoTrainer to share in the wards with your colleagues.

Bring out your Do-It-Yourself spirit and let’s start by listing the (little) necessary material:

  • a wooden board to use as a support 4 €
  • 3D printing of the trachea model provided by the AirwayApp project – 20€ ~
  • silicone sheets to simulate human skin – € 8.99 / 6 sheets
  • 4 pairs of bolts (screw + nut) 1 €
  • 2 rectangular pieces of wood
  • double-sided tape 2/3 €

In total, you will spend about thirty euros and you will get a spectacular result, trust me.

Assemble everything in 3 steps

  1. Prepare the wooden board (1) and apply a clear varnish to make it washable.
  2. Center the 3D printed model of the trachea (2) with respect to the wooden board and block it with the two wooden sticks (5), one on each side, applied oblique with the double-sided tape, will act as guides to insert and remove the trachea by simply sliding it until it stops.
  3. Fix the 4 screws (4) to the wooden board that will be used to stop the silicone sheet using the 4 screwed nuts

To give the simulation a touch of realism, between the 3D model of the trachea and the skin-colored silicone sheet I normally add a small bag with about 20 ml of fake blood inside, of which a simple recipe follows to create it.

To make everything washable in case you want to use fake blood I recommend (as I did) to cover the whole wooden board with washable transparent varnish (or a color of your choice).

Ingredients to create blood, feasible even for non-cooks like me:

  • 2 tablespoons of water
  • 2 tablespoons of sugar
  • a few drops of red food coloring you find at the supermarket
  • 2 tablespoons of flour type 00
  • 1/2 tablespoon of cocoa powder

This home-made mannequin is a slightly more advanced version than other tutorials found in #FOAMed as it makes use of a 3D printed model of the trachea which can be replaced (as shown here) with tubes for fans for example, of course losing simulation fidelity.

3D model of the trachea
To print your trachea 3D, there are various online services where by uploading the file (you can download it at the following link) you can receive the model at home after choosing some production options.

You are now ready to train for cricothyroidotomy! Mount a silicone sheet and… cut the neck! Share the photos of your created mannequins and leave your ideas to create more and more realistic ones.

References

  1. Heard, A. M. B., Green, R. J., & Eakins, P. (2009). The formulation and introduction of a “can”t intubate, can’t ventilate’ algorithm into clinical practice. Anaesthesia, 64(6), 601–8. https://doi.org/10.1111/j.1365-2044.2009.05888.x
  2. T. M. Cook, S. R. MacDougall-Davis; Complications and failure of airway management, BJA: British Journal of Anaesthesia, Volume 109, Issue suppl_1, 1 December 2012, Pages i68–i85, https://doi.org/10.1093/bja/aes393
  3. Parmet, J. L., Colonna-Romano, P., Horrow, J. C., Miller, F., Gonzales, J., & Rosenberg, H. (1998). The laryngeal mask airway reliably provides rescue ventilation in cases of unanticipated difficult tracheal intubation along with difficult mask ventilation. Anesthesia and Analgesia, 87(3), 661–5. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/9728849
  4. Cook, T. M., Woodall, N., Harper, J., Benger, J., & Fourth National Audit Project. (2011). Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 2: intensive care and emergency departments. British Journal of Anaesthesia, 106(5), 632–42. https://doi.org/10.1093/bja/aer059
  5. Pracy, J. P., Brennan, L., Cook, T. M., Hartle, A. J., Marks, R. J., McGrath, B. A., … Patel, A. (2016). Surgical intervention during a Can’t intubate Can’t Oxygenate (CICO) Event: Emergency Front-of-neck Airway (FONA)? British Journal of Anaesthesia, 117(4), 426–428. https://doi.org/10.1093/bja/aew221
  6. Frerk, C., Mitchell, V. S., McNarry, A. F., Mendonca, C., Bhagrath, R., Patel, A., … Difficult Airway Society intubation guidelines working group. (2015). Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults. British Journal of Anaesthesia, 115(6), 827–48. https://doi.org/10.1093/bja/aev371