An insulin pump is a small external medical device used to administer continuous insulin infusion in the subcutaneous tissue. It is computerized and programmed and is a good alternative to repetitive daily and painful injections. The device comes in many configurations and designs. It is becoming popular due to its ability to imitate body’s mechanism of insulin release thus helping in a better control of blood sugar levels. It can be programmed to deliver bolus doses or small continuous doses.
ORIGIN
The first insulin pump was designed by Dr. Arnold Kadish in 1963. It was in the form of a backpack. Later a more comfortable to wear device was designed by Dean Kamen in 1976. Since then, insulin pump has seen a lot of technological and aesthetic improvements.
PARTS OF AN INSULIN PUMP
Traditionally every insulin pump is made up of a pump, reservoir, infusion set with tubing.
- A pump or control device has the controls, batteries, microcircuit, screen and a reservoir. It is worn externally on a belt or carried in a pocket or can be attached with a holster.
- Cartridge or a Reservoir is a disposable container for insulin which is placed inside the pump.
- Infusion set connects the insulin reservoir to the patient. The tubing interface has cannula at one end and at the other end it is attached to the reservoir. The cannula is inserted into the subcutaneous tissue and fixed firmly onto the skin with a strong adhesive.
WHO REQUIRES INSULIN PUMP?
- Patients who are on insulin therapy especially Type 1 diabetics who require multiple insulin injections in a day
- Patients on insulin therapy for a long time.
- Patients with inadequate sites for injections due to site atrophy or dystrophy.
- Very young or very old patients.
HOW DOES IT WORK?
An insulin pump is programmed to deliver a bolus dose or a continuous insulin delivery. It is used to administer short acting and rapid acting insulins. Different dosing regimens via a pump are:
- Basal dose or basal rate: In this the pump mimics body’s insulin delivery mechanism. The pump is programmed to deliver specific units of insulin at every half hour or one hour as per the need. The dose of drug delivery may require an adjustment in case of an increased or decreased physical activity, fever, other diseases, hormonal imbalances etc.
- Bolus dose: It is administered as a bolus dose depending on the amount of carbohydrates consumed in a meal. Typically it is 1unit of insulin per gram of carbohydrates.
- Supplemental/ correctional dose: This is taken when the blood glucose levels are high before a meal and this correctional dose can bring it down to required range.
- Temporary dose: The dose can be increased or decreased as per the demand. For example, if a patient is going to participate in an activity requiring increased physical stress then he/she can choose to reduce the dose. Or, in case overeating or eating a high carbohydrate diet the dosage can be increased.
ADVANTAGES OF USING AN INSULIN PUMP
- Improved quality of life since it is more comfortable and discreet.
- Freedom from repeated painful injections.
- Freedom from dependence on diet and exercise regime for blood sugar control.
- Gives a more accurate dosing of insulin.
- Improved levels of blood sugar and glycosylated hemoglobin (HgbA1c).
- Allows more flexibility in eating amount and types of food.
- Reduces risk of hypoglycemic episodes.
- Use of short or rapid acting insulin eliminates risks associated with long-acting insulins.
- More freedom to indulge in sports, exercise and other intense physical activities without the fear of hypoglycemia.
- Ease of calculating dose in smarter pumps which have dose calculating functions.
- Accurate drug history can be obtained anytime.
- Patients on pumps have reported a lesser incidence of neuropathy.
- Improved sexual performance, improved esteem has been reported with the use of pumps.
DISADVANTAGES OF USING A PUMP
- More expensive to maintain.
- Some patients may find continuous wearing irksome.
- Swimming, showering or participating in a more rugged sport may need planning as the patient may need to detach the device. Also, the patient may miss the dose being delivered at the time. The device will need reprogramming after that.
Weight gain is more often seen in patients with pumps. - In case of device malfunction, dislodging of the cannula or if a patient forgets to switch on the device for many hours then diabetic emergency may occur.
- Use of strong adhesive to fix the cannula may trigger irritation or hypersensitivity reaction locally.
- The skin area around the cannula may have scarring.
- Proper training required before starting which may warrant a day’s stay at a medical facility.
POINTS TO REMEMBER WHILE USING PUMP
- Calculate basal and bolus doses precisely under supervision before managing on your own.
- Learn to calculate Insulin to carbohydrate ratio.
- Know adequately how much insulin to reduce or increase as per your demand.
- Report to your doctor in case of any doubt.
- Always have backup of cartridges, and sets.
- Develop strict insulin regime and stick to it.
- In case you have to detach or switch off your pump, set an alarm and remember to switch the pump on. Do not be off the pump for too long. Ask your doctor as to how long you can afford to be off the pump.
- Even though pumps are waterproof, avoid submerging them in a shower or a pool. Take care to prevent any damage to it.
- Do regular blood sugar checks and maintain a good record of blood sugar and insulin intake.
- While travelling carry a stock of all the supplies. Also carry insulin pens or syringe and needle in case you are unable to use the pump.
- If going through metal detectors, inform the security personnel about your pump. Avoid detaching your pump.