Developers: Marisha Madhira and Nick Sieja
Supervising Professor: Kevin Caves
Abstract
The use of In-Home Oxygen Therapy has revolutionized treatment options for patients with diseases like COPD and Emphysema. The use of an Oxygen Concentrator to provide supplemental oxygen improves quality of life for patients, but the convenience of this method is limited by the long lengths of tubing needed to walk around one’s home. To mitigate tripping hazards and wear on tubing due to these long lengths, we propose a simple automated tubing reel. Powered by a rechargeable 12V battery, the motor is remotely operated via the use of a button, which can be operated from 50 ft. When the button is pressed, the device reels the tubing in. The back of the device also contains a manual reset button in case the remote is lost. Our device is mounted to a table and can be moved to any hard surface. The handle acts for easy transportation of this 3.5 lbs. device. After device evaluation, it is found that the device appropriately reels in oxygen tubing, without a loss of oxygen flow from the concentrator. The client is pleased with the progress we have made on the device.
Introduction
The use of In-Home Oxygen has become the standard of care for patients with Chronic Obstructive Pulmonary Disease (COPD) and severe hypoxia [1]. COPD is a pulmonary disease which makes it difficult to breathe, and is the fourth leading cause of death in the United States [2]. Home Oxygen Therapy has been found to prolong time to “readmission or death” for patients with diseases like COPD [3]. Our client, Steve, has COPD and Emphysema, a related disease which also hinders breathing, and requires oxygen for 24 hours a day. Steve uses an oxygen concentrator (Figure 1), which purifies the air around to provide oxygen[4].
Although in home oxygen can improve the quality of life for patients like Steve, the convenience of this method is limited by the amount of tubing required to walk around one’s home. Oxygen concentrators can be bulky and loud, meaning that they are often stationed in one room and long tubes are used to reach other parts of a home. Our client manages more than 40 feet of tubing within his home, but it poses a tripping hazard as well as wear on the tube due to stepping on it or pulling it around corners. In a study of adverse events due to supplemental oxygen, nearly 46% of those interviewed reported tripping over equipment [5].
There have been previously marketed solutions to managing oxygen tubing, but they come with limitations which make them unideal for our client’s specific situation. One marketed solution is the Oxy Tube Remote, which reels or dispenses oxygen tubing into a box provided by the user [6]. Although this method is relatively inexpensive, it requires set up by the user, and does not neatly roll tubing, allowing wear on the tubes due to kinks. Another method is Tidy Tubing, which is a coiled tube which acts like a spring to coil and recoil with movement[7]. This does not meet our client goals as it may still get stuck around corners and will not fit under doors. Lastly, fully automated reels which may be mounted to walls or ceiling exist, sold by Freedom Oxygen. However, these cost upwards of $8000 and require special installation[8].
Project Goals
Our client would like to reduce issues due to the length of tubing in our client’s home. The more apparent issues include the tripping hazard, the wear on the tube caused by stepping or pulling it around corners, and constant use of one hand to manage excess tubing. The goal of this project is to develop a system that reduces the tripping risk and degree of general wear and tear, as well as liberates client’s hands to be used for other activities. Based on previous meetings, our client would like something which is also light, and low maintenance.
Design and Development
Our device is a motorized reel which can be operated via button press on a remote and on the reel itself. The oxygen tubing can be taken out of the reel freely, and then the operator can use the button press to turn the reel to neatly bring the tubing back in. Thus, the main components of the design are the reel itself, the motorized control of the reel, and clamping system for portability of the reel. As outlined in the Device Specifications and the Standards, this system follows the standards set forth for this assistive device. Furthermore, the output of oxygen through the reel is not compromised (less than 5% decrease) compared to the input and is in line with current clinical standards.
- Reel design
The reel is made from acrylic and can freely spin in one direction while being controlled by the motor in the other direction. Within the reel design, there is a barbed swivel hose connector on one side of the reel (connected to the left base plate). The base plate design is shown in Figure 2.
A swivel connector allows the tubing to freely spin on the inside of the wheel while keeping the external hosing steady on the outside.
- Motorized control of the reel
The tubing is automatically reeled in using a 12V 200RPM Brushless Geared DC Motor. This motor can be controlled by an Arduino microcontroller with inputs for power, ground, direction control, and Pulse Width Modulation (PWM). Using, PWM, the Arduino can change the speed of the motor.
For the client to control the reel remotely, the device is operated using a simple RF M4 315MHz Momentary Type receiver with a 315 MHz RF key fob Remote control (see https://www.adafruit.com/product/1096 for reference). This method was chosen because of the long range of communication available for RF trans mission and receiving, and the ease of integration of
the Adafruit system with an Arduino microcontroller. During testing, the RF receiver was able to pick up signal through walls up and 50 feet away from the transmitter. Lastly, a manual button press is on the device casing itself in case of loss of the remote (Figure 1). This is controlled by a simple button circuit which provides inputs to digital pins on the Arduino, which then communicates an appropriate PWM to the motor. The RF Sensor and circuit components are mounted to a PCB Arduino Shield (Figure 4).
- Mounted Assembly and Housing
Finally, the reel and motor system will have the ability to be mounted to any hard surface via a clamp. This clamp for the reel allows the system to be portable and for the user to move it to different locations if necessary. The handle on the box allows for easy transportation and reduces chances of damage due to dropping it.
Device Evaluation
Our client would like to reduce issues due to the length of tubing in our client’s home. The more apparent issues include the tripping hazard, the wear on the tube caused by stepping or pulling it around corners, and constant use of one hand to manage excess tubing. The goal of this project is to develop a system that reduces the tripping risk and degree of general wear and tear, as well as liberates client’s hands to be used for other activities. Based on previous meetings, our client would like something which is also light, and low maintenance.
Discussion and Conclusion
Our verification and validation checkpoints to demonstrate our device’s satisfaction of our overall criteria were met. No tests we performed indicated that we should expect device performance to deviate from the performance recorded during our testing trials, as variance between trial tests was low (example: normalized standard deviation of 0.062 for our reel speed trials). The results for every verification check are clearly listed and prove that our criteria have been met.
The large-scale problem we addressed was the damage caused to tubing when it is exposed to the home environment. Our device clearly mitigates this problem, as demonstrated by the satisfaction of requirement 3 in our verification plan. The tubing is effectively stored and protected by our device and is not damaged while on the reel.
The client was satisfied with the outcome of the device, and after a short testing period, he feels that the device will address his concerns, as seen in the user feedback survey. We conclude that this device minimizes hazards caused by exposed tubing without adding any new hazards to the integrity of the tubing. If used as indicated by the protocol in the user manual, the device should improve the user experience with home oxygen therapy.
References:
- Lacasse, Y., et al., Home Oxygen in Chronic Obstructive Pulmonary Disease. American Journal of Respiratory and Critical Care Medicine, 2018. 197(10): p. 1254-1264.
- NIH. COPD. 2018 [cited 2018 September 16]; Available from: https://www.nhlbi.nih.gov/health-topics/copd.
- Murphy, P.B., et al., Effect of home noninvasive ventilation with oxygen therapy vs oxygen therapy alone on hospital readmission or death after an acute copd exacerbation: A randomized clinical trial. JAMA, 2017. 317(21): p. 2177-2186.
- Phillips. EverFlo Home Oxygen System. 2018 [cited 2018 September 16]; Available from: https://www.usa.philips.com/healthcare/product/HC1020000/everflo-home-oxygen-concentrator.
- A Randomized Trial of Long-Term Oxygen for COPD with Moderate Desaturation. New England Journal of Medicine, 2016. 375(17): p. 1617-1627.
- Bags, O.T.C. Oxy Tube Remote. 2016 [cited 2018 September 16]; Available from: www.oxytubecontrolbags.com.
- COPDTools. COPDTools. 2017 [cited 2018 September 16]; Available from: https://www.copdtools.com/cart/.
- Freedom Oxygen Products LLC. The Freedom Oxygen Tubing System. 2018 [cited 2018 September 16]; Available from: https://www.freedomoxygenproducts.com/our-products.