Cricothyrotomy, last resort to establish an airway
Cricothyrotomy is a medical procedure that is used to establish an airway by puncturing through the skin and cricothyroid membrane in certain life-threatening cases, such as airway obstruction by a foreign body, angioedema, or massive facial trauma. Surgical cricothyrotomy and needle cricothyrotomy are the two main techniques used today. Surgical cricothyrotomy, where a scalpel is used to provide ventilation through an incision on the trachea, is the most effective procedure, but it is highly invasive. It requires a high level of skill, experience and optimal controlled working conditions. It might become challenging to perform even for surgically trained personnel.
Considering the rarity of the cases when emergency cricothyrotomy is needed and the potentially extreme conditions in a pre-hospital context, it is hard for Emergency Medical Service (EMS) personnel to fully adapt and master this technique. It also became clear during the research phase that paramedics do not feel comfortable using a scalpel because it is not their daily instrument.
The needle cricothyrotomy on the other hand, which is a procedure preferred by paramedics, is where a cannula is placed in the trachea through a needle from a syringe. It is easier to perform and preferred by the paramedics for several reasons, but also because of their daily experience of handling syringes. However, that it does not provide effective ventilation due the small diameters of the cannula.
CRIC is designed based on insights and feedback from professional paramedics and is a new type of surgical tool that combines the functionality of the two most basic tools within healthcare: the scalpel and the syringe to provide a new, quick and safe method of performing the life-saving cricothyrotomy procedure during the most difficult conditions possible: at an accident site or in a moving ambulance. CRIC provides confidence for EMS personnel to choose surgical cricothyrotomy instead of less effective procedures by minimizing the necessary skill and experience level required to perform an otherwise complicated procedure. It is a is a single-use tool that combines all the advantages of the needle and surgical cricothyrotomy in a form that is optimized for pre-hospital contexts.
There are several tools required to perform emergency cricothyrotomy used in sequence. Considering unforeseen pre-hospital emergency scenarios, using all these different types of equipment in a sequence and keeping them sterile at the same time, becomes an impossible challenge for the paramedics. Additionally, there might not be helping hands available in an emergency context. To address this problem, CRIC is designed to be a pre-loaded, ready to use and one-hand operated product that comes in a sterilized package together with sterilizing wipes. High contrasts colors are used on the parts with different functions to make it easy to differentiate and to make the sequence of actions cognitively clear to the user.
Another aspect that makes it challenging to perform surgical cricothyrotomy is that there is no control over the depth of the incision, deep incisions might result in major vessel injury. For this reason, it is common to make small and several incisions until the trachea is visualized. This results in loss of valuable time. With needle cricothyrotomy, depth can easily be controlled when using a syringe and needle. As the plunger is pulled back while advancing the needle, the bubbles from the positive pressure in the lungs are observed in the barrel. Inspired by this simple principle the CRIC accommodates a depth control mechanism to make a controlled and precise incisions. With the specialized 9 mm 'scalpel-needle' connected to the pre-loaded water chamber, the procedure of making the incision on the patient, acquiring the correct depth of the incision and securing the catheter in the airway can be done in-one-go.
The introducer head, on the tip of the tube, functions as a dilator. Since the tube is pre-placed on the blade, the tube is guided in place at the same time as the incision is made. By combining the incision and intubation into one, the problem that can arise in traditional procedures where one can lose track of the incision before the tube is safely inserted is eliminated. This way the procedure can be done not only safer but also quicker. The elliptical shape fitting better to the anatomy cricoid membrane makes the dilation easier and allows room for the 9 mm wide 'scalpel-needle blade'.
A Familiar Tool
The project started with an in-depth ethnography research phase at the Umeå ambulance station, Sweden. In this process, various methods for human centred-design was applied as a tool and catalyst to document, analyze and understand the characteristics of the users. One of the main insights from the user research was that paramedics were very skilled and aware that they must be able to improvise and sometimes perform drastic actions in the different emergency situations that they encounter in order to save the lives of their patients. With this reason, they like to understand their tools, take them apart if needed and use them in their own way. Based on this insight the CRIC was deliberately designed to be a manual and 'transparent' tool.
The idea behind the design of this scalpel-needle was also that paramedics do not feel comfortable with using a scalpel because it is a surgical instrument. On the other hand, syringes are their daily instrument. The aim was to keep the syringe metaphor, not only in the functionality but also in the overall form language so that the paramedics would feel familiar with the product.