Insulin Pump free essay sample

Introduction:1 †¢ Type 1 Diabetes2 †¢ Type 2 Diabetes2 †¢ Gestational Diabetes2 2. Scope:3 3. The insulin pump hardware organization:3 4. Need:4 5. Requirements for the insulin pump:4 6. Risks Analysis5 6. 1 Business Impact Risks:5 6. 2 Customer related risks:5 6. 3 Technology risks:6 7. Risk table:6 7. 1 Technology will meet expectations:6 7. 2 End users resist system:7 7. 3 Changes in Requirements7 7. 4 Lack of development experience:7 7. 5 Poor quality documentation:8 8. Insulin delivery system8 . Requirement Models9 10. Interfaces For The Automatic Insulin Pump10 11. Data Flow Diagram14 12. Summary15 13. References16 Introduction: The problem of diabetes is a growing concern in the world, especially among Americans. Diabetes is a medical condition where the body does not manufacture its own insulin. Insulin is used to metabolize sugar and, if it is not available, the person suffering from diabetes will eventually be poisoned by the build-up of sugar. It is importan t to maintain blood sugar levels within a safe range as high levels of blood sugar have long-term complications such as kidney damage and eye damage. These are not however, normally dangerous in the short-term. We will write a custom essay sample on Insulin Pump or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Very low levels of blood sugar (hypoglaecemia) are potentially very dangerous in the short-term. They result in a shortage of sugar to the brain which causes confusion and ultimately a diabetic coma and death. In such circumstances, it is important for the diabetic to eat something to increase their blood sugar level. An estimated 23. 6 million people in the United States—7. 8 percent of the population—have diabetes, a serious, lifelong condition. Of those, 17. 9 million have been diagnosed, and 5. 7 million have not yet been diagnosed. In 2007, about 1. million people ages 20 or older were diagnosed with diabetes [pic] The three main types of diabetes are †¢ type 1 diabetes †¢ type 2 diabetes †¢ gestational diabetes †¢ Type 1 Diabetes Type 1 diabetes is an autoimmune disease. An autoimmune disease results when the body’s system for fighting infection—the immune system—turns against a part of the body. In diabetes, the immune sy stem attacks and destroys the insulin-producing beta cells in the pancreas. The pancreas then produces little or no insulin. A person who has type 1 diabetes must take insulin daily to live. †¢ Type 2 Diabetes The most common form of diabetes is type 2 diabetes. About 90 to 95 percent of people with diabetes have type 2. This form of diabetes is most often associated with older age, obesity, family history of diabetes, previous history of gestational diabetes, physical inactivity, and certain ethnicities. About 80 percent of people with type 2 diabetes are overweight. †¢ Gestational Diabetes Some women develop gestational diabetes late in pregnancy. Although this form of diabetes usually disappears after the birth of the baby, women who have had gestational diabetes have a 40 to 60 percent chance of developing type 2 diabetes within 5 to 10 years. Maintaining a reasonable body weight and being physically active may help prevent development of type 2 diabetes. The easiest way for Type 2 patients to manage their health is through a healthy diet and exercise plan. For Type 1 patients, treatment almost always involves the daily injection of insulin, which is the focus of the Automated Insulin Pump System (AIPS). Currently, there are two ways in which a patient can administer insulin. In the first method, the user must check his or her blood sugar with a glucose sensor, calculate the appropriate amount of insulin to administer, and personally inject the insulin. In the second method, the patient uses an AIPS. The AIPS detects the level of glucose in the user’s blood, calculates the amount of insulin need, then triggers a pump to administer the correct dosage to the user via a needle that inserted into the user. Both of these methods require the user to play a critical role in his or her treatment. Using the AIPS minimizes the possibility of errors occurring. To accomplish this, the AIPS integrates the blood glucose sensor and the insulin pump into one system. Integrating these two processes allows the autonomous delivery of insulin to the user. This ability of the system to remove the user from the glucose self monitoring and injection process allows diabetics to live a healthier and more enjoyable lifestyle. Scope: We are developing a that system measures the level of blood sugar every 10 minutes and if this level is above a certain value and is increasing then the dose of insulin to counteract the increase is computed and injected into the diabetic. The system can also detect abnormally low levels of blood sugar and, if these occur, an alarm is sounded to warn the diabetic that they should take some action. This report focuses on the control software for the insulin pump which is concerned with reading the blood sugar (glucose) sensor, computing the insulin requirements and controlling the micro pump which causes the insulin to be delivered. Automatic insulin delivery systems help to keep blood glucose level under control. Administering insulin with different methods aims to improve patients comfort and convenience. Automated Insulin pumps are little computerized insulin deliverers. Automatic insulin delivery systems can be used for treating type 1 diabetes, type 2 diabetes, gestational diabetes, juvenile diabetes, diabetes mellitus and alike. But, the information about diabetes is crucial for having the perfect diabetes medication. The insulin pump hardware organization: An insulin pump is a safety-critical system which is used to deliver regular doses of insulin to diabetics. A block diagram of the insulin pump assembly is shown below. Note that the small boxes marked s indicate a sensor. [pic] Figure 2: The insulin pump hardware organization †¢ Needle assembly Connected to pump. Component used to deliver insulin into diabetic’s body. †¢ Sensor Measures the level of sugar in the patient’s blood. The input from the sensor is represented by Reading in the following specification. Pump Pumps insulin from a reservoir to the needle assembly. The value representing the number of increments of insulin to be administered is represented by dose! in the following specification. †¢ Controller Controls the entire system. This has a three position switch (off/auto/manual) plus a button to set the number o f units of insulin to be delivered (1 unit per press). Moving the switch to the manual position causes the blood sugar measurement and automated insulin delivery to be disabled but information is maintained about the amount of insulin delivered and the reservoir capacity. †¢ Alarm Sounded if there is some problem. The value sent to the alarm is represented alarm! In the following specification. Displays There are 3 displays. These displays are represented by display1, display2 and clock in the following specification. display1 displays system messages, display2 shows the last dose of insulin delivered and clock shows the current clock time. †¢ Clock Provides the controller with the current time. The system clock is initialized when the machine is installed and the start time of each 24-hour period is set at midnight each day using a hardware interface on the machine. For safety reasons, the clock cannot be altered by system users. Need: With almost 200 million with diabetes world wide and about 400,000 patients currently on insulin pumps, there is sufficient market potential to spur further development, and at least 6 companies are selling devices in the U. S. Very short clinical trials have proven the concept of a closed-loop system, but the technology must catch up for long-term implantation. By 2015 there could well be an implanted closed-loop system on the market. It will likely take several years longer before it is clear when the device is a superior alternative to other advancing technologies. Requirements for the insulin pump: This specification is a specification of the requirements for the control software for the insulin pump. It is NOT a complete system requirements specification for the pump itself or even all of the software associated with the pump. In particular, it does not include a specification of the self-testing operations or a specification of the hardware interfacing. The requirements for the insulin pump are specified in natural language and partially in the Z specification language. Z is not ideal to express all requirements but is useful when precise descriptions are required. In all cases, the Z specification should be considered as an annotation that provides detailed information which augments the natural language specification. [pic] Figure 2: Insulin pump Risks Analysis: Alarm condition Explanation: |Alarm conditions |Explanation | |Battery low |The voltage of the battery has fallen to less than 0. V | |Sensor failure |The self-test of the sugar sensor has resulted in an error | |Pump failure |The self-test of the pump has resulted in an error | |Delivery failure |It has not been possible to deliver the specified amount of insulin | |Needle assembly removed |The user has removed the needle assembly | |Insulin reservoir removed |The user has removed the insulin reservoir | |Low insulin level |The level of insulin is low (indicating that the reservoir should be changed). | Table 1: Error conditions for the insulin pump. 6. 1 Business Impact Risks: The number of the customer is fairly high. There is large number of users of insulin pump. Their need is considered consistent as all target users will be patients of diabetes. Sophistication of end users: Low, the target users are patients of diabetics. Automatic insulin pump is designed to be easy to use, and is supplied with directions to guide through all necessary steps in using the machine. 6. 2 Customer related risks: Past coordination: We are developing software because of the increased of diabetes among which children are also included. So to give them facility we are developing complete new program that will help them a lot. †¢ Customer information: Customer has the idea how to use it because of already available automatic pumps in the market but this one is more sophisticated and all directions are given with it as well. 6. 3 Technology risks: Familiarity: Automatic insulin pump is a software tool to aid diabetic patients. Development team members are familiar with software development, as well as the necessary data base implementation. Specialized user interface: The interface is completely specialized. It is not based on anything other than every other Microsoft Windows application out. The GUI is completely our design and no other application out (to our knowledge) contains exactly what is expected of our software. Risk table: |Risks |Probability |Impact | |Technology will meet expectations |25% 1 | |End user resist system |20% |1 | |Changes in requirement |20% |2 | |Lack of development experience |20% |2 | |Poor quality documentation |35% |2 | Impact Values: 1 – Catastrophic 2 – Critical 3 – Marginal 4 – Negligible 7. 1 Technology will meet expectations: †¢ Mitigation In order to prevent this from happening, meetings (formal and informal) will be held with the customer on a routine business. This in sures that the product we are producing, and the specifications of the customer are equivalent. †¢ Monitoring The meetings with the customer should ensure that the customer and our organization understand each other and the requirements for the product. Management Should the development team come to the realization that their idea of the product Specifications differs from those of the customer, the customer should be immediately notified and whatever steps necessary to rectify this problem should be done. Preferably a meeting should be held between the development team and the customer to discuss at length this issue. 7. 2 End users resist system: †¢ Mitigation In order to prevent this from happening, meetings (formal and informal) will be held with the customer on a routine business. This insures that the product we are producing, and the requirements of the customer are equivalent. †¢ Monitoring The meetings with the customer should ensure that the customer and our organization understand each other and the requirements for the product. †¢ Management Should the development team come to the realization that their idea of the product requirements differs from those of the customer, the customer should be immediately notified and whatever steps necessary to rectify this problem should be taken. Preferably a meeting should be held between the development team and the customer to discuss at length this issue. 7. 3 Changes in Requirements †¢ Mitigation In order to prevent this from happening, meetings (formal and informal) will be held with the customer on a routine business. This insures that the product we are producing, and the requirements of the customer are equivalent. †¢ Monitoring The meetings with the customer should ensure that the customer and our organization understand each other and the requirements for the product. †¢ Management Should the development team come to the realization that their idea of the product requirements differs from those of the customer, the customer should be immediately notified and whatever steps necessary to rectify this problem should be taken. Preferably a meeting should be held between the development team and the customer to discuss at length this issue. 7. 4 Lack of development experience: †¢ Mitigation In order to prevent this from happening, the development team will be required to learn the languages and techniques necessary to develop this software. The member of the team that is the most experienced in a particular facet of the development tools will need to instruct those who are not as well versed. †¢ Monitoring Each member of the team should watch and see areas where another team member may be weak. Also if one of the members is weak in a particular area it should be brought to the attention by that member, to the other members. †¢ Management The members who have the most experience in a particular area will be required to help those who don’t out should it come to the attention of the team that a particular member needs help. 7. 4 Poor quality documentation: †¢ Mitigation In order to prevent this to happening, members who are in charge of developing the documentation will keep in contact with witch developer on the team. Meeting will be held routinely to offer documentation suggestions and topics. Any topic deemed missing by a particular developer will be discussed and it will be decided whether or not to add that particular topic to that documentation. In addition, beta testers will be questioned about their opinion of the documentation. †¢ Monitoring Throughout development or normal in and out of house testing, the development team and or beta testers will need to keep their eyes open for any possible documentation topics that have not been included. †¢ Management Should this occur, the organization would call a meeting and discuss the addition of new topics, or removal of unnecessary topics into the documentation. Insulin delivery system [pic] Requirement Models [pic] Figure 3: Requirement Use Case Diagram [pic] Interfaces For The Automatic Insulin Pump The user interface displays all relevant system information to the user, as well as all controls needed to operate the system in â€Å"manual† mode. The GUI displays the current time, the last time a dose of insulin was administered, and the corresponding amount of that dose. If any hardware component malfunctions while the system is running, a system alarm indicator activates, prompting the user to check the system messages. This alarm is both auditory and visual. By scrolling through the system messages, the user can isolate the source of the error and take appropriate measures. Other indicators on the GUI show the level of charge in the battery and the amount of insulin remaining in the reservoir, there is also a history button which displays a table containing a history of blood sugar values and doses. [pic] Figure 5: System User Interface. [pic] Figure 6: System User Interface During Failure [pic] Figure 7: Table of history of the system. Besides displaying relevant system information, the user interface also functions as a control panel for manual operation of the insulin pump. To deliver a manual dose of insulin, the toggle switch controlling the operation mode must be set to manual. Once the system is running in manual mode, the user may press the â€Å"Inject 1 Unit† button to deliver one unit of insulin. Even in manual mode the system users decisions are checked make sure they do not exceed the maximum daily dose. Figure 7 illustrates the error message from attempting to deliver more than the maximum daily dosage. [pic] Figure 8: Visual Notification of Maximum Insulin Dose for the Day. In addition to the User Interface a hardware simulator was design and coded to run on beneath the insulin pump and provide the backend with different state levels for the various internal variables. Figure 8 displays the portion of the GUI that displays the internal variables. Data Flow Diagram [pic] Summary There may be at least 640,000 who good candidates for the insulin pump. It is an especially useful advance for many type 1 patients whose glucose control is difficult to manage and require several injections of insulin and glucose checks a day. It is still unclear whe n the pump is beneficial for type 2 patients. †¢ The technology has come a long way with an integrated system that continuously monitors glucose, a management system with algorithms providing advice on amount of insulin required and an external pump injecting insulin through a subcutaneous canula. This â€Å"advise you† open loop system dramatically increases the complexity of management. It has beneficial for those dedicated to its use, but it is unclear when it should be used. †¢ Diabetes experts feel current pumps (with or without continuous glucose monitoring) are best used by those who are knowledgeable, very meticulous in their diabetes management and accept fact that the system requires a lot of attention. These people value the benefits of the pump. Others do not desire using a pump system and get about the same satisfactory results with multiple daily injections as they would by trying to manage a pump. †¢ Controlled studies on the benefits of insulin pumps and continuous glucose monitoring are still needed to demonstrate a clear benefit over other aggressive therapeutic options. This applies to both type 1 and type 2 patients. †¢ The current integrated system is very expensive – up to $7,500 a year for the disposable sensors, canulas and insulin plus the cost of the pump. It requires insertion of new glucose sensors and insulin canulas every 3 days or more often and attention to detail in safely keeping all the components functioning properly. Focused attention is also required in adjusting and administering bolus insulin doses. †¢ Many insurers provide reimbursement for the pump. Diabetes advocacy groups (JDRF ADA) are working hard to secure insurance and Medicaid coverage for the continuous glucose monitoring component with its expensive disposable components. Within the next 2-4 years, an implanted pump will be available that will allow more freedom, but at more expense and risk. It will work like the new external pumps and can be used with the independent subcutaneous glucose monitor. It will not be a closed-loop system. †¢ With ov er 400,000 people worldwide currently using pumps and many more considering pump usage, there appear to be sufficient marketplace incentives to encourage technological advances. Our rough estimates suggest 650,000 in the US might benefit from these systems. References †¢ http://74. 125. 155. 132/search? q=cache:- valCGvPRHEJ:www. comp. lancs. ac. uk/computing/resources/IanS/SE7/CaseStudies/InsulinPump/Slides/Insulin-pumpOverview. ppt+scope+of+diabetes+in+software+enginee