Beshoy Hosny Agayby
Asthma is becoming a major health issue in many developing countries and is characterised by recurrent attacks of breathlessness and wheezing. Asthma inhalers are hand-held portable devices that deliver medication to the lungs to control asthma symptoms. We offer a low-cost, easy to print inhaler and spacer that can help those affected by asthma anywhere in the world.
Spacers, also known as aerosol-holding chambers, are large, empty tubes that increase delivery of medication from pressurised metered dose inhalers (MDIs). MDIs deliver medication in a mist or spray. However, it can be difficult to inhale them properly as one needs to breathe in slowly, deeply and at the exact same time as the medication is released. The effectiveness of inhaler delivered asthma medication is increased with the use of a spacer. Furthermore, the use of a spacer has been shown to be superior to a nebulizer in terms of cost effectiveness. For low resource settings, where access to nebulizer equipment may be limited, an affordable spacer device similar to the Volumatic ™ will improve care greatly. By increasing the availability of the medication when delivered to the lungs, the use of a spacer aims to decrease medication usage and pulmonary associated morbitidites in order to drive down costs.
A 3D printed spacer device was designed. The key design requirement is a non-rebreather valve, to ensure that dispensed medication is not blown out by exhalations into the device. A seperate device will be made available soon which conforms to the Evohaler ™ connection standards, allowing retrofitting of the spacer device with patients existing inhaler devices.
Typical spacers cost between €5 and €25 and are usually made of plastic. Our PLA 3D printed spacing device comes to a cost of €4.27 with no additional transportation fees.
The most recent global estimate of asthma suggests that there are as many as 334 million people with asthma. It is a common disease among children, however it can also develop during adulthood. Frequent effects of asthma include sleeplessness, daytime fatigue, reduced activity levels in school and work absenteeism. Asthma symptoms may occur as frequently as several times a day depending on the severity of the condition. Physical activity can enhance the frequency and severity of the asthma attacks. Shortness of breath and wheezing result from the airways narrowing, which reduces the flow of air into and out of the lungs.
Increased urbanisation has disrupted the traditionally low incidence of asthma in the Third World. In order to help asthma patients, we have to improve their access to medication. Although inhalers are not extremely expensive, transportation costs are significant contributors. By 3D printing the inhaler, the costs and space needed for transportation will be reduced. Moreover, in war zones and regions hit by natural disasters transportation is difficult, hence 3D printed inhalers can play an important role in aiding patients.
The inhaler was designed on the commonly used Ventolin ™ inhaler and can be used with Evohaler ™ inhaler canisters.
Reflex hammers are medical devices used to test deep tendon reflexes. Reflex tests are performed as part of the neurological examination and help to identify anomalies in the neural circuits involved in generating the reflex. Our designed reflex hammers are able to elicit a broad range of reflexes and have a production cost around ten times lower than the price of commercial neurological reflex hammers available on the market.
Reflex hammers are used by neurologists to verify the integrity of the spinal cord and the peripheral nervous system. This verification is important as 90 out of 100,000 people in the United States suffer from spinal cord injury, while an estimated 20 million American people suffer from peripheral neuropathy. Also, the Guillain-Barré syndrome, which results in nerve cell damage, affects 1 to 9 in 100,000 people worldwide. In addition, it has been estimated that 15% of diabetic patients develop diabetic neuropathy after 20 years of disease.
Furthermore, in the Third World countries, where malnutrition is recurrent, especially in regions where white rice forms most of the diet, Beriberi symptoms can develop. Most of these conditions can be diagnosed using reflex hammers. Hence, we designed and built two different models of the reflex hammer: the Queen Square reflex hammer and the Tomahawk (or Taylor) reflex hammer. The former is mostly used by UK neurologists, while the latter by American practitioners. The Queen Square and the Tomahawk reflex hammers are sold for a price that can range from €12 to €20 and €10 to €30, respectively.
Using both reflex hammers, we were able to reproduce reflexes ("knee-jerk" reflex, the Achilles reflex and the triceps reflex). We also tested the ability of our 3D printed models to generate these reflexes in comparison with a professional Queen Square hammer. To this end, we carried out a "knee-jerk" reflex test on 7 people, and concluded that there is no statistically significant difference between our models and the commercially available ones (see the graph below).
Our model of the Queen Square reflex hammer comes in two parts (the head and the handle), while the Tomahawk reflex hammer is printed in one piece.