September 1, 2021
Continuous subcutaneous insulin infusion (CSII) through a pump provides an alternative means of delivering insulin. It is the most physiological method of delivering insulin. It provides continuous subcutaneous delivery of short-acting insulin infusion (Lispro or Aspart) all day long and replaces the need for multiple daily injections in diabetics, especially type-1 diabetic patients. Preferred n patients uncontrolled on multiple injections and those needing excellent control such as in pregnancy, especially suitable for patients with risk of hypoglycemia, uncertain lifestyle, and mealtimes.
Insulin pumps are small, the size of a smartphone, computerized devices that mimic the way a human pancreas work. Many pumps connect wirelessly with glucometer devices. Some can connect with continuous glucose monitoring devices.
The first insulin pump was created in 1974. It was so large that it was worn as a backpack. Today they are so small that they can be kept in a pocket. New insulin pumps have many added features. When it is integrated with a continuous glucose monitoring device, (closed-loop insulin therapy), it works as an artificial pancreas. It senses basal insulin requirements and automatically adjusts the insulin delivery. Continuous glucose monitoring systems suspend insulin delivery if the glucose level reaches a threshold.
Insulin pumps deliver insulin in two ways. Basal rates and a bolus dose.
The basal rate is a programmed small amount of continuous insulin delivery set up by the doctor depending on the need of the user. There can be more than one programmed basal setting. Basal requirements can be influenced by the factors such as illnesses, puberty, medication such as glucocorticoids, and exercise.
Bolus dose can be delivered on demand to match the food or to correct high blood sugar. Most pumps come with a bolus insulin calculator that helps to calculate bolus dose depending on glucose reading and carbohydrate counting.
Types of pumps
A variety of pumps are available. In general, there are two types of pump devices.
Traditional insulin pump
Traditional pumps are battery-operated (2 AA alkaline batteries) small computerized devices. It includes a reservoir for insulin, a pumping mechanism, and an infusion set. Tube length varies depending on where you want to wear the pump. The reservoir can hold 300 units of insulin and is changed every 2 or 3 days along with the infusion set. The pump is worn with a belt around the waist. It delivers insulin by an infusion set attached to a cannula. There is a variety of accessories available, so you can carry a pump with the style. The pump infusion rate is adjusted to maintain glucose in a normal range. The pump body contains control buttons or has a touch screen.
Insulin patch pumps or Omnipods
It includes a reservoir and infusion set in a small case without tubing and it is waterproof. The device is worn on the body with self-adhesive tape. Patch pumps are controlled wirelessly by a separate device that allows the programming of insulin delivery from the patch. Patch pumps are usually replaced every three days.
Features of insulin pumps may include, rechargeable batteries, remote control, dual hormone insulin pumps (that can inject glucagon too), programmable bolus, reminders, alerts for missed bolus dose or missed glucose measurements, and alarm in the event of a blockage.
Benefits of insulin pumps
- Fewer needles pricks
- Better glucose control and Improved HbA1c scores. Substantially reduce the variability of glucose levels.
- Fewer hypoglycemic events, especially overnight.
- Insulin pumps provide more flexibility with bolus injection in both timing and shape and also in changing basal rates. Pumps can be preprogrammed to compensate for nocturnal and early morning glucose fluctuations. Pumps can be discontinued for a short period of activities like exercise or a temporary basal rate option can be set to reduce or increase basal rate during exercise or illnesses.
- Dose calculation: pumps can connect wirelessly to glucometers which send reading to the bolus calculator. The built-in bolus wizard feature calculates the insulin requirement with current glucose level, carbohydrate intake, and personal insulin setting.
- Weight control and better quality of life.
- Far more costly than insulin pens and syringes
- Frequent and meticulous self-monitoring and close attention to pump function are necessary for the safe and effective use of insulin pumps. Only motivated and committed people can use it.
- pump failure, Pumps can malfunction, sometimes especially if the batteries are discharged or the reservoir runs out causing an interruption in insulin supply.
- There can be a kink in tubing, bubbles, or leaks.
- Inconvenience, as you have to wear it all the time.
- Skin problems can occur at the site of infusion, such as injection site abscess