Insulin pumps

Overview 

An insulin pump is a compact, wearable medical device designed to provide a continuous flow of rapid-acting insulin beneath the skin. These small, computerized pumps are roughly the size of a juice box or deck of cards and offer an alternative to multiple daily insulin injections. They are used by individuals with diabetes who require insulin to manage their condition, delivering a steady dose to help maintain stable blood glucose levels. 

The technology behind insulin pumps has advanced rapidly, and many pumps now integrate with continuous glucose monitoring (CGM) systems. This integration allows the pump to automatically adjust insulin delivery based on real-time glucose levels, providing more precise management and reducing the need for frequent manual adjustments.

Types  

There are two main types of insulin pumps: tubed pumps and tubeless pumps. 

Tubed insulin pumps 

A tubed (or tethered) insulin pump delivers insulin through a long, thin tube connected to a cannula under your skin. Key components of a tubed insulin pump include: 

• Pump and technology: The pump itself is a durable device made of plastic and metal, equipped with a screen to monitor settings and data. It holds a reservoir of insulin, typically sufficient for two to three days, and may feature a rechargeable or replaceable battery depending on the model. The amount of insulin it can store varies between pumps, but it’s generally filled according to the user’s needs. The pump can be clipped to clothing or carried in a pocket. 

• Tubing and infusion set: The tubing connects the insulin reservoir in the pump to the infusion set attached to the skin. The infusion set is adhered to the skin and contains a short cannula (a flexible plastic tube) inserted under the skin. The cannula is inserted manually or with a special device and held in place by adhesive. The insertion involves a needle that pierces the skin, which is removed afterward, leaving only the cannula in place. Common insertion sites include the upper arm, abdomen, hips, buttocks, or thighs. 

Both the insulin reservoir and infusion set typically need to be changed every two to three days or when the reservoir runs out of insulin. Each time, new tubing, reservoirs, and infusion sets are used, while the pump itself can last several years. Some tubed pumps are waterproof, though many are only water-resistant, requiring the user to disconnect the pump during activities like showering or swimming. 

Tubeless insulin pumps 

Tubeless (or patch) insulin pumps deliver insulin without external tubing. Instead, they use a pod that contains both the insulin reservoir and the cannula, which is adhered directly to the skin. The pump is controlled wirelessly with a handheld device. 

Similar to tubed pumps, the pod is replaced every two to three days, or when the insulin runs out. Before applying the pod, the reservoir is filled with insulin, and the adhesive patch is attached to the skin. A button triggers the insertion of a needle through the cannula, which then retracts, leaving the cannula in place. The pod can be worn in areas like the upper arm, abdomen, hip, buttock, or thigh. 

One advantage of tubeless pumps is that they are typically waterproof, allowing users to swim or bathe without needing to remove the device.

Reasons for undergoing the procedure  

An insulin pump can be used by any diabetic who needs synthetic insulin. This includes those individuals with Type 1 diabetes and those with Type 2 diabetes, including adults and children. A pump may also be used by those with monogenic diabetes or Type 3c diabetes. 

One option for managing diabetes with insulin therapy is an insulin pump. An insulin pump might be appropriate for you (or your child) if you:  

• Encounter dawn phenomenon, where blood sugar levels rise in the early morning.  
• Experience gastroparesis, which causes delays in food absorption.  
• Have irregular schedules and/or eating patterns.  
• Need small insulin doses, often seen in toddlers and children with diabetes.  
• Planning for pregnancy.  
• Seek greater flexibility and accuracy in insulin dosing.  
• Struggle to achieve your desired blood sugar range with multiple daily injections (MDI).

Insulin pumps may not be the ideal choice for everyone, including:  

• Problems with hand movements: Difficulty using your hands and fingers to load or fill an insulin reservoir and operate pump buttons, which can be challenging with conditions like hand arthritis or neuropathy.  
• Visual impairment: Limited options due to visual impairment, considering factors such as screen size, contrast, letter and number size, and backlighting available on the pump.  
• Challenges in keeping the pump attached: Severe skin allergies or sensory problems that make it difficult to maintain the pump attached nearly all the time, which is required for optimal performance.  

Risk  

Insulin delivery issues are a major drawback of insulin pumps when compared to multiple daily injections. These may occur for a number of causes, such as:  

• Cannulas that is bent or kinked: A cannula may bend or kink due to pressure or strain from the body tissue beneath your skin. This may prevent insulin from entering your body.  
• Crystallization of insulin: You might not receive the entire dosage of insulin if, after two to three days, insulin crystallizes, or forms fibrils, in the cannula or tubing. For this reason, it’s important to replace the majority of infusion sets and tubeless pumps every two to three days.  
• Disconnection of infusion set from the tubing: It is possible for the tubing on a tubed pump to separate from the infusion site without your knowledge. Instead of entering your body through the tubing, the insulin spills out of it.  
• Inflammation or blood clot at the infusion site: Insulin may not go to the right places in your body if there is a lot of inflammation or a blood clot close to your cannula.  
• Tubing that is torn or kinked: The pump tubing may become kinked (from knots) or torn (if a pet chews through it), preventing insulin delivery to your body.  
• Adhesive issues: Adhesives are used to attach infusion sites and tubeless pumps to your skin; this might lead to unintentional tearing or premature peeling off. Using more adhesives can help avoid this problem.  
• Pump failure: On a rare cases, your insulin pump may fail or break, and it may also run out of battery power.

Sometimes, your insulin pump will detect a blockage (occlusion) and notify you to change the pump or infusion set. However, if the set becomes disconnected from the tubing, the pump may not detect this issue. If you use a CGM, you might observe an unexpected rise in your glucose levels, indicating an insulin delivery problem.

Going without insulin for a period of time, usually hours, increases the risk of severe high blood sugar (hyperglycemia) and potentially life-threatening diabetes-related ketoacidosis (DKA).

If you use a pump, it is important to respond promptly and to have a backup plan in case of possible problems with insulin delivery. This could include:  

• Carrying insulin and additional pump supplies when you’re away from home.  
• Keeping injectable insulin, syringes, or an insulin pen readily available.  
• Having the customer service number of your pump manufacturer accessible for quick assistance with any technological issues.

To prevent these issues or detect them early, make it a habit to check your pump and/or infusion set at least once daily. Regularly monitoring your blood sugar levels is also essential. 

Other factors that could be seen as insulin pump disadvantages include as follows:  

• Cost: Compared to MDI insulin therapy, insulin pumps and the supplies they need can be expensive.  
• Constant attachment to your body: Insulin pumps are like an extra piece of hardware that is permanently attached to your body. Even though there are discreet ways to wear them, getting used to this can take some time.  
• Supply quantity: Insulin pumps require more supplies than MDI, which means that more space needs to be set aside for storage at home and that extra packing is required when traveling, especially on long trips.  
• Adhesives problems: The skin adhesives used with insulin pumps and infusion sets may cause allergic responses in certain people.  

Procedure  

An insulin pump delivers insulin in one of two approaches replicating the way your pancreas naturally releases insulin:  

• Basal insulin: This is a small and continuous insulin doses. Throughout the day, your insulin pump probably has a number of basal rates that are adjusted in hourly increments. Because your body needs different levels of background insulin during the course of a day, that variety is required. For example, natural cortisol spikes which increase blood sugar levels in the morning cause many people to require more background insulin. You will need to gradually modify these basal rates as your body and everyday activities change, seeking advice from your healthcare provider as needed. Any pump can be programmed to automatically modify basal dosages in response to real-time glucose readings from a connected continuous glucose monitor. Also, a manual setting on the majority of pumps enables users and healthcare providers to program basal rates.  
• Bolus: Insulin is manually increased during meals and to treat high blood sugar. Your blood sugar level and carbohydrate intake are entered into the pump, which utilizes this information to determine how much bolus insulin you require. Before delivering the insulin, the majority of pumps provide you with a recommended dose that you can verify or modify. 

Different pump types and brands have different settings and technologies. A few examples are:  

• Integration with CGM technology to enable insulin delivery to be automatically adjusted according to your blood glucose levels.  
• The capacity to manually change basal rates during certain periods.  
• Low battery or reservoir level alerts.  
• If the pump and CGM data are synchronized, alerts for glucose levels outside of range will be sent.  
• Connectivity with other smart devices and smartphone apps. 

Outcome  

When selecting an insulin pump, there are numerous things to take into account. This is an important choice. The good news is that pump manufacturers have experts who can answer your questions and provide you with plenty of information about their pumps. An additional helpful resource is your diabetic healthcare provider. 

An insulin pump has several advantages over multiple daily injections. These advantages include:  

• Adjustable insulin delivery settings in some pumps for different meal types and exercise, enabling precise insulin dosing.   
• Integration of insulin delivery with CGM technology.   
• Access to downloadable data for adjusting management strategies with your endocrinologist.   
• Improved blood sugar control, as evidenced by studies showing better management among long-term pump users compared to those using MDI.   
• Enhanced quality of life reported by many individuals who transition from MDI to an insulin pump.   
• Reduction in the number of insulin injections required. 

The majority of endocrinologists and diabetes specialists advocate for the use of insulin pumps because of their proven benefits supported by evidence.

Many diabetics find insulin pumps to be a more convenient alternative for flexible insulin delivery than needles. It’s important to keep in mind that utilizing an insulin pump is not a commitment; if you change your mind, you can return to receiving injections.