Insulin pump

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Insulin pump
Insulin pump and infusion set.JPG
Paradigm insulin pump 530g, showing an infusion set loaded into spring-loaded insertion device called serter. A reservoir is attached to the infusion set (shown here removed from the pump).
Insulin pump in use Insulin pump with infusion set.jpg
Insulin pump in use
Child diabetic wearing a state-of-the-art insulin pump (referred to as a "patch pump"). His waterproof device needs no one infusion set Jonge-diabetespatint-met-insulinepomp-op-de-huid-geplakt-1326488205.jpg
Child diabetic wearing a state-of-the-art insulin pump (referred to as a "patch pump"). His waterproof device needs no one infusion set

An insulin pump is a medical device used for the administration of insulin in the treatment of diabetes mellitus, also known as continuous subcutaneous insulin therapy. The device configuration may vary depending on design. A traditional pump includes:

Contents

Other configurations are possible. More recent models may include disposable or semi-disposable designs for the pumping mechanism and may eliminate tubing from the infusion set.

An insulin pump is an alternative to multiple daily injections of insulin by insulin syringes or an insulin pen and allows for flexible insulin therapy when used in conjunction with blood glucose monitoring and carbohydrate counting.

Medical uses

Insulin pumps are used to deliver insulin on a continuous basis to a person with type I diabetes.

Advantages

Disadvantages

Insulin pumps, cartridges, and infusion sets may be far more expensive than syringes used for insulin injection with several insulin pumps costing more than $6,000; necessary supplies can cost over $300. [3] Another disadvantage of insulin pump use is a higher risk of developing diabetic ketoacidosis if the pump malfunctions. [3] This can happen if the pump battery is discharged, if the insulin is inactivated by heat exposure, if the insulin reservoir runs empty, the tubing becomes loose and insulin leaks rather than being injected, or if the cannula becomes bent or kinked in the body, preventing delivery. [3] Therefore, pump users typically monitor their blood sugars more frequently to evaluate the effectiveness of insulin delivery.

Accessibility

Use of insulin pumps is increasing because of:

History

In 1974, the first insulin pump was created and was named the Biostator. The first pump was a 60 kg bedside device. [10] It also had the capability of monitoring blood glucose levels, so this also doubles as the first continuous glucose monitor. Between 1978 and 1988, Robert Channon, working with Guy's Hospital and the Bristol Royal Infirmary, developed a series of miniature insulin infusion pumps. [11] [12] Today, insulin pumps are so small that they can fit in a pocket or a purse.

In 1984, an Infusaid implantable infusion device was used to treat a 22-year-old patient successfully. [13]

The insulin pump was first endorsed in the United Kingdom in 2003 by the National Institute for Health and Care Excellence (NICE).

Developments

New insulin pumps are becoming "smart" as new features are added to their design. These simplify the tasks involved in delivering an insulin bolus.

MiniMed 670G is a type of insulin pump and sensor system created by Medtronic. It was approved by the US FDA in September 2016 and was the first approved hybrid closed loop system which senses a patient's basal insulin requirement and automatically adjusts its delivery to the body. [20] [21] [22]

Mylife YpsoPump, developed by Ypsomed, was launched in Europe in 2016. [23] Eli Lilly had planned to work with Ypsomed to introduce this to the United States, but that effort was terminated in 2022. [23]

Omnipod 5: On January 28, 2022, Insulet Corporation announced the FDA has approved the Omnipod 5, the first tubeless closed loop insulin pump with Smartphone control, working with the Dexcom G6 Continuous Glucose Monitor. The Omnipod 5 will have a feature named SmartAdjust technology that allows for the increase, decrease, or suspension of insulin based on the user's custom blood glucose targets. [24]

INSUL by AgVa: AgVa Healthcare announced that Insul by Agva is the world's most advanced and affordable Insulin pump. Features such as a built-in glucometer, Bluetooth connectivity, android and IOS app, as well as long-lasting and economical disposables. [25]

Future developments

Dosing

Filling an insulin pump reservoir. (Left to right) 1: Reservoir in sterile packaging. 2: Filling the reservoir. 3: Reservoir with needle and plunger removed, ready for attachment to infusion set. Insulin pump reservoir.jpg
Filling an insulin pump reservoir. (Left to right) 1: Reservoir in sterile packaging. 2: Filling the reservoir. 3: Reservoir with needle and plunger removed, ready for attachment to infusion set.
Standard bolus.JPG
Extended bolus.JPG
Combo bolus.JPG
Super bolus.JPG

An insulin pump allows the replacement of slow-acting insulin for basal needs with a continuous infusion of rapid-acting insulin.

The insulin pump delivers a single type of rapid-acting insulin in two ways: [29]

Bolus shape

An insulin pump user can influence the profile of the rapid-acting insulin by shaping the bolus. Users can experiment with bolus shapes to determine what is best for any given food, which means that they can improve control of blood sugar by adapting the bolus shape to their needs.

A standard bolus is an infusion of insulin pumped completely at the onset of the bolus. It's the most similar to an injection. By pumping with a "spike" shape, the expected action is the fastest possible bolus for that type of insulin. The standard bolus is most appropriate when eating high carb low protein low fat meals because it will return blood sugar to normal levels quickly.

An extended bolus is a slow infusion of insulin spread out over time. By pumping with a "square wave" shape, the bolus avoids a high initial dose of insulin that may enter the blood and cause low blood sugar before digestion can facilitate sugar entering the blood. The extended bolus also extends the action of insulin well beyond that of the insulin alone. The extended bolus is appropriate when covering high fat high protein meals such as steak, which will be raising blood sugar for many hours past the onset of the bolus. The extended bolus is also useful for those with slow digestion (such as with gastroparesis or coeliac disease).

A combination bolus/multiwave bolus is the combination of a standard bolus spike with an extended bolus square wave. This shape provides a large dose of insulin up front, and then also extends the tail of the insulin action. The combination bolus is appropriate for high carb high fat meals such as pizza, pasta with heavy cream sauce, and chocolate cake.

A super bolus is a method of increasing the spike of the standard bolus. Since the action of the bolus insulin in the blood stream will extend for several hours, the basal insulin could be stopped or reduced during this time. This facilitates the "borrowing" of the basal insulin and including it into the bolus spike to deliver the same total insulin with faster action than can be achieved with spike and basal rate together. The super bolus is useful for certain foods (like sugary breakfast cereals) which cause a large post-prandial peak of blood sugar. It attacks the blood sugar peak with the fastest delivery of insulin that can be practically achieved by pumping.

Bolus timing

Since the pump user is responsible to manually start a bolus, this provides an opportunity for the user to pre-bolus to improve upon the insulin pump's capability to prevent post-prandial hyperglycemia. A pre-bolus is simply a bolus of insulin given before it is actually needed to cover carbohydrates eaten.

There are two situations where a pre-bolus is helpful:

  1. A pre-bolus of insulin will mitigate a spike in blood sugar that results from eating high glycemic foods. Infused insulin analogs such as NovoLog and Apidra typically begin to reduce blood sugar levels 15 or 20 minutes after infusion. As a result, easily digested sugars often hit the bloodstream much faster than infused insulin intended to cover them, and the blood sugar level spikes upward as a result. If the bolus were infused 20 minutes before eating, then the pre-bloused insulin would hit the bloodstream simultaneously with the digested sugars to control the magnitude of the spike.
  2. A pre-bolus of insulin can combine a meal bolus and a correction bolus when the blood sugar is above the target range before a meal. The timing of the bolus is a controllable variable to bring down the blood sugar level before eating again causes it to increase.

Similarly, a low blood sugar level or a low glycemic food might be best treated with a bolus after a meal is begun. The blood sugar level, the type of food eaten, and a person's individual response to food and insulin affect the ideal time to bolus with the pump.

Basal rate patterns

The pattern for delivering basal insulin throughout the day can also be customized with a pattern to suit the pump user.

Basal rate determination

Basal insulin requirements will vary between individuals and periods of the day. The basal rate for a particular time period is determined by fasting while periodically evaluating the blood sugar level. Neither food nor bolus insulin must be taken for 4 hours before or during the evaluation period. If the blood sugar level changes dramatically during evaluation, then the basal rate can be adjusted to increase or decrease insulin delivery to keep the blood sugar level approximately steady.

For instance, to determine an individual's morning basal requirement, they must skip breakfast. On waking, they would test their blood glucose level periodically until lunch. Changes in blood glucose level are compensated with adjustments in the morning basal rate. The process is repeated over several days, varying the fasting period, until a 24-hour basal profile has been built up which keeps fasting blood sugar levels relatively steady. Once the basal rate is matched to the fasting basal insulin need, the pump user will then gain the flexibility to skip or postpone meals such as sleeping late on the weekends or working overtime on a weekday.

Many factors can change insulin requirements and require an adjustment to the basal rate:

A pump user should be educated by their diabetes care professional about basal rate determination before beginning pump therapy.

Temporary basal rates

Since the basal insulin is provided as a rapid-acting insulin, the basal insulin can be immediately increased or decreased as needed with a temporary basal rate. Examples when this is helpful include:

Security

In August 2011, an IBM researcher, Jay Radcliffe, demonstrated a security flaw in insulin pumps. Radcliffe was able to hack the wireless interface used to control the pump remotely. [30] Pump manufacturer Medtronic later said security research by McAfee uncovered a flaw in its pumps that could be exploited. [31]

See also

Related Research Articles

<span class="mw-page-title-main">Hypoglycemia</span> Health condition

Hypoglycemia, also called low blood sugar, is a fall in blood sugar to levels below normal, typically below 70 mg/dL (3.9 mmol/L). Whipple's triad is used to properly identify hypoglycemic episodes. It is defined as blood glucose below 70 mg/dL (3.9 mmol/L), symptoms associated with hypoglycemia, and resolution of symptoms when blood sugar returns to normal. Hypoglycemia may result in headache, tiredness, clumsiness, trouble talking, confusion, fast heart rate, sweating, shakiness, nervousness, hunger, loss of consciousness, seizures, or death. Symptoms typically come on quickly.

Intensive insulin therapy or flexible insulin therapy is a therapeutic regimen for diabetes mellitus treatment. This newer approach contrasts with conventional insulin therapy. Rather than minimize the number of insulin injections per day, the intensive approach favors flexible meal times with variable carbohydrate as well as flexible physical activities. The trade-off is the increase from 2 or 3 injections per day to 4 or more injections per day, which was considered "intensive" relative to the older approach. In North America in 2004, many endocrinologists prefer the term "flexible insulin therapy" (FIT) to "intensive therapy" and use it to refer to any method of replacing insulin that attempts to mimic the pattern of small continuous basal insulin secretion of a working pancreas combined with larger insulin secretions at mealtimes. The semantic distinction reflects changing treatment.

The following is a glossary of diabetes which explains terms connected with diabetes.

<span class="mw-page-title-main">Blood glucose monitoring</span> Use of a glucose monitor for testing the concentration of glucose in the blood

Blood glucose monitoring is the use of a glucose meter for testing the concentration of glucose in the blood (glycemia). Particularly important in diabetes management, a blood glucose test is typically performed by piercing the skin to draw blood, then applying the blood to a chemically active disposable 'test-strip'. The other main option is continuous glucose monitoring (CGM). Different manufacturers use different technology, but most systems measure an electrical characteristic and use this to determine the glucose level in the blood. Skin-prick methods measure capillary blood glucose, whereas CGM correlates interstitial fluid glucose level to blood glucose level. Measurements may occur after fasting or at random nonfasting intervals, each of which informs diagnosis or monitoring in different ways.

Basal rate, in biology, is the rate of continuous supply of some chemical or process. In the case of diabetes mellitus, it is a low rate of continuous insulin supply needed for such purposes as controlling cellular glucose and amino acid uptake.

<span class="mw-page-title-main">Glucose meter</span> Medical device for determining the concentration of glucose in the blood

A glucose meter, also referred to as a "glucometer", is a medical device for determining the approximate concentration of glucose in the blood. It can also be a strip of glucose paper dipped into a substance and measured to the glucose chart. It is a key element of glucose testing, including home blood glucose monitoring (HBGM) performed by people with diabetes mellitus or hypoglycemia. A small drop of blood, obtained from slightly piercing a fingertip with a lancet, is placed on a disposable test strip that the meter reads and uses to calculate the blood glucose level. The meter then displays the level in units of mg/dL or mmol/L.

<span class="mw-page-title-main">Type 1 diabetes</span> Form of diabetes mellitus

Type 1 diabetes (T1D), formerly known as juvenile diabetes, is an autoimmune disease that originates when cells that make insulin are destroyed by the immune system. Insulin is a hormone required for the cells to use blood sugar for energy and it helps regulate glucose levels in the bloodstream. Before treatment this results in high blood sugar levels in the body. The common symptoms of this elevated blood sugar are frequent urination, increased thirst, increased hunger, weight loss, and other serious complications. Additional symptoms may include blurry vision, tiredness, and slow wound healing. Symptoms typically develop over a short period of time, often a matter of weeks if not months.

The term diabetes includes several different metabolic disorders that all, if left untreated, result in abnormally high concentrations of a sugar called glucose in the blood. Diabetes mellitus type 1 results when the pancreas no longer produces significant amounts of the hormone insulin, usually owing to the autoimmune destruction of the insulin-producing beta cells of the pancreas. Diabetes mellitus type 2, in contrast, is now thought to result from autoimmune attacks on the pancreas and/or insulin resistance. The pancreas of a person with type 2 diabetes may be producing normal or even abnormally large amounts of insulin. Other forms of diabetes mellitus, such as the various forms of maturity-onset diabetes of the young, may represent some combination of insufficient insulin production and insulin resistance. Some degree of insulin resistance may also be present in a person with type 1 diabetes.

An insulin analog is any of several types of medical insulin that are altered forms of the hormone insulin, different from any occurring in nature, but still available to the human body for performing the same action as human insulin in terms of controlling blood glucose levels in diabetes. Through genetic engineering of the underlying DNA, the amino acid sequence of insulin can be changed to alter its ADME characteristics. Officially, the U.S. Food and Drug Administration (FDA) refers to these agents as insulin receptor ligands, although they are usually just referred to as insulin analogs or even just insulin.

Many types of glucose tests exist and they can be used to estimate blood sugar levels at a given time or, over a longer period of time, to obtain average levels or to see how fast body is able to normalize changed glucose levels. Eating food for example leads to elevated blood sugar levels. In healthy people, these levels quickly return to normal via increased cellular glucose uptake which is primarily mediated by increase in blood insulin levels.

Automated insulin delivery systems are automated systems designed to assist people with insulin-requiring diabetes, by automatically adjusting insulin delivery in response to blood glucose levels. Currently available systems can only deliver a single hormone—insulin. Other systems currently in development aim to improve on current systems by adding one or more additional hormones that can be delivered as needed, providing something closer to the endocrine functionality of the pancreas.

The untethered regimen is a technique combining the use of an insulin pump with a slow-acting insulin analog such as Lantus or Levemir. This allows an insulin dependent person to disconnect the pump when desired while maintaining the flexible benefits that the insulin pump can provide.

<span class="mw-page-title-main">Diabetes management software</span>

Diabetes Management Software refers to software tools that run on personal computers and personal digital assistants to help persons with Type 1 and Type 2 diabetes manage the data associated with:

<span class="mw-page-title-main">Insulin (medication)</span> Use of insulin protein and analogs as medical treatment

As a medication, insulin is any pharmaceutical preparation of the protein hormone insulin that is used to treat high blood glucose. Such conditions include type 1 diabetes, type 2 diabetes, gestational diabetes, and complications of diabetes such as diabetic ketoacidosis and hyperosmolar hyperglycemic states. Insulin is also used along with glucose to treat hyperkalemia. Typically it is given by injection under the skin, but some forms may also be used by injection into a vein or muscle. There are various types of insulin, suitable for various time spans. The types are often all called insulin in the broad sense, although in a more precise sense, insulin is identical to the naturally occurring molecule whereas insulin analogues have slightly different molecules that allow for modified time of action. It is on the World Health Organization's List of Essential Medicines. In 2021, it was the 179th most commonly prescribed medication in the United States, with more than 2 million prescriptions.

<span class="mw-page-title-main">Minimed Paradigm</span> Insulin pumps

MiniMed Paradigm is a series of insulin pumps manufactured by Medtronic for patients with diabetes mellitus. The pump operates with a single AAA battery and uses a piston-plunger pump to infuse a programmed amount of insulin into the patient through a length of tubing. The Paradigm uses a one-way wireless radio frequency link to receive blood sugar measurements from select glucose meters. The Paradigm RT series adds the ability to receive data from a mated continuous blood-glucose monitor. Although the pump can use these measurements to assist in calculating a dose of insulin, no actual change in insulin delivery occurs without manual user-intervention.

DexCom, Inc. is a company that develops, manufactures, produces, and distributes continuous glucose monitoring (CGM) systems for diabetes management. It operates internationally with headquarters in San Diego, California, and has manufacturing facilities in Mesa, Arizona and Batu Kawan, Malaysia.

Tandem Diabetes Care is an American medical device manufacturer based in San Diego, California. The company develops medical technologies for the treatment of diabetes and specifically insulin infusion therapy.

Nightscout is a free and open-source project, and associated social movement, that enables accessing and working with continuous glucose monitor (CGM) data. Nightscout software aims to give users access to their real time blood sugar data by putting this data in the cloud. In addition to browser-based data visualization, Nightscout can also be used to review data from a phone or smartwatch, or to remotely monitor CGM data for individuals with type 1 diabetes. Associated with Nightscout software is a broader "CGM in the Cloud" social movement, supporting individuals seeking to access and use realtime CGM data through commercial and DIY approaches.

The Open Artificial Pancreas System (OpenAPS) project is a free and open-source project that aims to make basic artificial pancreas system (APS) technology available to everyone. The OpenAPS project was designed with the idea of quickly getting the APS technology to more people using a direct approach, rather than waiting for clinical trials to be completed and regulatory approval to be granted.

<span class="mw-page-title-main">Continuous glucose monitor</span> Blood glucose monitoring device

A continuous glucose monitor (CGM) is a device used for monitoring blood glucose on a continual basis instead of monitoring glucose levels periodically by drawing a drop of blood from a finger. This is known as continuous glucose monitoring. CGMs are used by people who treat their diabetes with insulin, for example people with type 1 diabetes, type 2 diabetes, or other types of diabetes, such as gestational diabetes.

References

  1. ↑ Kesavadev J, Kumar A, Ahammed S, Jothydev S (2008). "Experiences with Insulin Pump in 52 Patients with Type 2 Diabetes in India". DiabetesPro. American Diabetes Association. 2021-PO. Archived from the original on 24 February 2012.
  2. ↑ Muppidi R. "Insulin Pump Training". Advanced Endocrine and Diabetes Hospital. AED Hospital. Retrieved 3 December 2019.
  3. 1 2 3 4 5 Millstein R, Becerra NM, Shubrook JH (December 2015). "Insulin pumps: Beyond basal-bolus". Cleveland Clinic Journal of Medicine (Review). 82 (12): 835–842. doi: 10.3949/ccjm.82a.14127 . PMID   26651892.
  4. ↑ Graveling AJ, McIntyre EA (January 2009). "Insulin Delivery Devices". Journal of the Royal College of Physicians of Edinburgh. 39 (2): 146–150.
  5. ↑ Conget Donlo I, Serrano Contreras D, Rodríguez Barrios JM, Levy Mizrahi I, Castell Abat C, Roze S (2006). "[Cost-utility analysis of insulin pumps compared to multiple daily doses of insulin in patients with type 1 diabetes mellitus in Spain]". Revista Espanola de Salud Publica (in Spanish). 80 (6): 679–695. doi: 10.1590/s1135-57272006000600008 . PMID   17147307.
  6. ↑ Zisser H, Wagner R, Pleus S, Haug C, Jendrike N, Parkin C, et al. (December 2010). "Clinical performance of three bolus calculators in subjects with type 1 diabetes mellitus: a head-to-head-to-head comparison". Diabetes Technology & Therapeutics. 12 (12): 955–961. doi:10.1089/dia.2010.0064. PMID   21128842.
  7. ↑ Steineck I, Cederholm J, Eliasson B, Rawshani A, Eeg-Olofsson K, Svensson AM, et al. (June 2015). "Insulin pump therapy, multiple daily injections, and cardiovascular mortality in 18,168 people with type 1 diabetes: observational study". BMJ. 350 (jun22 1): h3234. doi:10.1136/bmj.h3234. PMC   4476263 . PMID   26100640.
  8. ↑ Kesavadev J, Rasheed SA. "Dramatic Response of Painful Peripheral Neuropathy with Insulin Pump in Type 2 Diabetes". DiabetesPro. American Diabetes Association. 2097-PO. Archived from the original on 24 February 2012.
  9. ↑ Kesavadev J, Balakrishnan S, Ahammed S, Jothydev S (August 2009). "Reduction of glycosylated hemoglobin following 6 months of continuous subcutaneous insulin infusion in an Indian population with type 2 diabetes". Diabetes Technology & Therapeutics. 11 (8): 517–521. doi:10.1089/dia.2008.0128. PMID   19698065.
  10. ↑ Mascini M (April 2007). A Brief Story of Biosensor Technology, chapter in Biotechnological Applications of Photosynthetic Proteins: Biochips, Biosensors and Biodevices. pp. 4–10. Retrieved 24 March 2023.
  11. ↑ "Insulin pump calls the shots". New Scientist. Vol. 88, no. 1226. 6 November 1980. p. 369. Retrieved 24 March 2023.
  12. ↑ "Multiple injection infusion device (portable), UK Patent Application GB2222525A, 28 March 1988" (PDF). Google Patents. Retrieved 24 March 2023.
  13. ↑ Campbell IW, Kritz H, Najemnik C, Hagmueller G, Irsigler K (July 1984). "Treatment of type I diabetic with subcutaneous insulin resistance by a totally implantable insulin infusion device ("Infusaid")". Diabetes Research. 1 (2): 83–88. PMID   6442226.
  14. ↑ "What is SmartGuard™ Technology?". 12 March 2018.
  15. ↑ "Animas Vibe and CGM-system". Animas. Archived from the original on 23 January 2014. Retrieved 28 January 2014.
  16. ↑ "Animas Vibe Insulin Pump with Latest Dexcom CGM Technology Now Available in Canada". CNW. Archived from the original on 16 July 2015. Retrieved 28 January 2014.
  17. ↑ Brown A (17 October 2017). "Animas Closes Operations and Exits Insulin Pump Market". Diatribe.org. Retrieved 24 March 2018.
  18. ↑ "FDA authorizes first interoperable insulin pump intended to allow patients to customize treatment through their individual diabetes management devices". FDA. 14 February 2019. Retrieved 4 March 2021.
  19. ↑ "FDA authorizes first fully interoperable continuous glucose monitoring system, streamlines review pathway for similar devices". FDA. 27 March 2018. Retrieved 4 March 2021.
  20. ↑ "Recently approved devices: The 670G System - P160017". FDA. 28 September 2016.
  21. ↑ a. Dealing with any kind of medical technology, there are going to be pros and cons. With an insulin pump there are many to consider. Some of the pros of insulin pump therapy are precise insulin delivery down to the 0.025 minimum. They also replace the need to give a shot each time you eat. It allows for easier exercise management. Another large pro to an insulin pump is the reduced chance of variability with the patient’s blood glucose levels. Some of the cons are the cost of the insulin pump and supplies, the risk of infection at the pump site, and risk of DKA because of a pump malfunction.
  22. ↑ "What are the Advantages and Disadvantages of an Insulin Pump?". Children's Hospital of Michigan. 18 November 2019. Retrieved 8 May 2021.
  23. 1 2 Whooley, Sean (9 December 2022). "Eli Lilly discontinues Ypsomed collaboration to pursue its own U.S. insulin pump offering". Medical Design & Outsourcing. Retrieved 10 December 2022.
  24. ↑ "Omnipod® 5 | Omnipod". www.omnipod.com. Retrieved 28 January 2022.
  25. ↑ "INSUL by AgVa | AgVa Healthcare" . Retrieved 29 March 2022.
  26. ↑ Brown A, Liu N (31 March 2014). "Dr. Ed Damiano Presents Next Set of Bionic Pancreas Study Results at ATTD". diaTribe. The diaTribe Foundation. Retrieved 19 March 2015.
  27. ↑ "Humalog prescribing information" (PDF). Eli Lilly and Company. 2019.
  28. ↑ "Linjeta duration of action". Biodel, Inc. Archived from the original on 31 March 2013.
  29. ↑ "Insulin pumps". Diabetes.co.uk. 15 January 2019.
  30. ↑ "Insulin Pumps Vulnerable to Hacking". Fox News . Associated Press. 22 October 2015.
  31. ↑ "Exclusive: Medtronic probes insulin pump risks". Reuters. 25 October 2011.
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