Automated Syringe Dosing Hanson, E.E., Weisshaar, C.L., Wentland, A.L. BME 402 Department of Biomedical Engineering University of Wisconsin-Madison May 4, 2005 Advisor Willis J. Tompkins, Ph.D., Professor Department of Biomedical Engineering Abstract Many people, especially elderly individuals, have afflictions along with diabetes, including poor eyesight, tremors, loss of dexterity, arthritis, multiple sclerosis, and other neuromuscular disorders. These disabilities make it difficult for patients to measure and administer medications with a syringe. We have developed a device that electronically drives the plunger on a standard syringe, reducing the dexterity normally needed with dosing a syringe. We have constructed a prototype that demonstrates the feasibility of driving the syringe on a screw-based system with a bimodal stepper motor. We have begun to program a microprocessor for controlling a keypad, motor, and digital display.Syringe Dosing 2/40 Table of Contents Page Abstract 1 Table of Contents 2 Problem Statement 3 National Student Design Competition 3 Schoofs Prize for Creativity 3 Background 4 Current Products 6 Contacts 7 Design Constraints 7 Design Approaches 8 Design Evaluation 10 Our Chosen Design 11 Syringe Dosing Device: Operation 12 Prototype 13 Construction of the Prototype 13 Syringe Dosing Device: Advantages 15 Syringe Dosing Device: Disadvantages 15 Syringe Calibration and Preliminary Testing 16 Schoofs Prize for Creativity: Claims and Marketing Information 17 Smaller Motor 19 Microprocessor 20 Future Work 23 Ethical Considerations 23 Conclusions 24 References 25 Appendix A: PDS 28 Appendix B: Expenses 32 Appendix C: BASIC program for counting zero through nine 33 Appendix D: Master BASIC program for the design 37Syringe Dosing 3/40 Problem Statement Our goal is to develop a syringe delivery device that uses standard 1 cc syringes (BD Ultra-FineTM Needles [1]) and sets the dosage on those syringes within 0.01 cc accuracy. This device should minimize the dexterity typically needed with dosing a syringe, along with being easy to use for elderly patients and those with poor eyesight. Ideally, this machine is geared towards patients who use syringes on a daily basis, such as those diagnosed with diabetes. Patients afflicted with maladies in addition to diabetes, such as neuromuscular disorders and poor eyesight, would also benefit greatly from this device. National Student Design Competition This project is part of the 2004-2005 National Student Design Competition, an undergraduate competition funded by the Rehabilitation Engineering Research Center on Accessible Medical Instrumentation [2]. In conjunction with Marquette University, Professor John Enderle of the University of Connecticut chairs the competition. The competition is open to students predominantly in biomedical engineering and industrial design. In the 2004-2005 competition, student teams have a choice of three projects: a weight scale, a syringe dosing device, or an ergometer, all to assist patients of diabetes, obesity, paralysis, and neuromuscular disorders. At the University of Wisconsin – Madison, another team is working on an ergometer [3] while our team is working on a syringe dosing device. Schoofs Prize for Creativity The team also chose to participate in the Schoofs competition. Part of this competition incorporated market research to develop a marketing plan. As part of this research, we determined the market, insurance costs and coverage, and future prospects for this type of a device. Marketing research will be provided later in this paper.Syringe Dosing 4/40 Background Diabetes is one of the leading causes of disability in the United States, causing dementia, low testosterone levels in males, excessive thirst, frequent urination, fatigue, changes in vision, blindness, stroke, nerve damage, and the need for amputation [4, 5]. Diabetes is typically treated with insulin injections, where the amount of insulin is determined by eating habits, exercise, and ultimately a patient’s blood glucose level. While the changes in vision make it difficult for patients to see and set the dosage on the syringe, elderly diabetes patients commonly acquire neuromuscular diseases, albeit unrelated to diabetes. Nevertheless, these diseases make it difficult for patients to control syringes. Type 2 diabetes is the most common form of diabetes, affecting 18.2 million people in the United States alone. This type is found in 90-95% of the diabetes patients [6]. Those most often afflicted with this disease are older people. The Center for Disease Control [6] has predicted that the number of American diabetes patients will increase as Baby Boomers grow older and more sedentary. Type 2 diabetes is characterized by a high blood glucose level, a high insulin level, and a resistance to insulin (Figure 1). Contrary to type 1 diabetes, where insulin does not get produced in proper quantities, type 2 diabetics cannot use their insulin effectively [5]. A person with diabetes must take daily precautions to maintain optimal health. These include healthy eating, exercise, and blood glucose testing. Blood glucose testing will tell if the Figure 1. Type 2 Diabetes. In this disease, users develop a resistance to insulin, and therefore, blood glucose levels rise [7].Syringe Dosing 5/40 blood sugar levels are too low (hypoglycemia) or too high (hyperglycemia) [4]. Irregular blood sugar levels can cause illness, dizziness, nervousness, confusion, fainting, and/or impaired judgment [4]. Depending on the blood sugar level, insulin may be administered. The injection procedure should be done as recommended by an endocrinologist and is as follows [8]: 1. Wash hands and area where injecting (usually a fatty subcutaneous tissue area such as the stomach). 2. Wash medicine bottle top with cotton ball and alcohol. 3. Draw air into the syringe equal to the volume of fluid needed. 4. Insert needle into medicine bottle and depress plunger, pushing all air out of the syringe. This action creates a vacuum and allows for easier and smoother filling and delivery. 5. Invert medicine