Oropharyngeal airways are commonly used by paramedics and first responders for short term airway management in unconscious patients when tracheal intubation is not available or contraindicated. When a patient is unconscious, the muscles in their jaw may relax and allow the tongue to cover the epiglottis, obstructing the airway. Using an oropharyngeal airway device is the quickest way to provide a patent airway. It can also facilitate suctioning, prevent a patient from biting his/her tongue, and aid in ventilation during CPR. The correct use of an oropharyngeal airway can be life-saving.
Commercially available oropharyngeal airways are generally made of hard plastic and come in various sizes. Reusable devices may come with a silicon rubber finish while disposable/single-use ones may be made of PVC plastic. The correct size is chosen by measuring from the angle of the jaw to the mouth of the patient. It is inserted upside down to avoid the patient’s teeth, and rotated 180 degrees over the tongue to allow air to pass through and around the device. The device extends from the lips to the pharynx of the patient.
We designed and 3D printed 3 oropharyngeal airways based on the standard dimensions for a small, medium and large sized adult. The 3D CAD model was designed on Solidworks® and 3D printed using an Ultimaker 2 3D-printer with polylactic acid (PLA) as the material. On the software Cura, the oropharyngeal airway was oriented vertically with the flange (part that protrudes from the mouth) on the baseplate. The device was printed under normal print speed, with support material, and normal PLA settings: 20% fill density, 50 mm/s print speed, 0.1mm layer height, and 210°C temperature. For each oropharyngeal airway of the different sizes, the time taken to print on normal print speed, the length of filament used and its approximate cost is as follows:
We successfully tested the use of the 3D printed oropharyngeal airways on a SimMan® patient simulator. We believe 3D-printing of oropharyngeal airways using PLA may provide a cheap, disposable and life-saving option for medical staff in emergency situations who are based in less-resourceful regions.
The following tables contain all the information related to the cost of the manufacturing of each device.
The total cost for the kit of three sizes oropharyngeal airways is 3.08€.
Prices have been calculated according to the next parameters:
The energy E in kilowatt-hours (kWh) is obtained from the power P in watts (W), times the time period t in hours (hr) divided by 1000:
E(kWh) = (P(W) x t(hr))/1000