Insulin is a hormone produced by the beta cells in the pancreas. With each meal, these beta cells release insulin to aid the body in storing or utilizing the blood glucose it receives from the food, into energy.
The main function of insulin is to maintain the normal level of glucose in the bloodstream
Diabetes is a serious metabolic disorder which is produced due to the impact of insulin. Diabetes disease can considerably affects the quality of life and can reduce life expectancy.
There are different types of diabetes and in different types of diabetes either there is reduced insulin production or the body cells fail to react to insulin (known as insulin resistance). This results in increased levels of blood sugar.
- In type 1 diabetes, as the beta cells are destroyed the pancreas fails to make insulin hence, insulin shots are required to utilize the glucose from meals thereby, controlling the blood sugar levels. In this type of diabetes, permanent insulin shots shall be required by the patient.
- In type 2 diabetes, beta cells in the pancreas produce sufficient amounts of insulin but the body fails to respond to the insulin thus, causing elevated blood sugar levels. In type 2 diabetes and in gestational diabetes, if medications fail to help the body in utilizing glucose for energy then, insulin shots are required.
To control the elevated levels of blood sugar, the patient may require different types or doses of insulin. Insulin therapy plays an important role in the management of diabetes and it can even prevent diabetes complications by keeping the blood sugar levels within control.
There are three main features which differ in different types of insulin. The three features are:
- Onset of action – It is the length of time required for the insulin to act after the administration of the injection. It is the time prior to insulin reaching the bloodstream and reducing blood glucose.
- Peak-time – It is the time when the insulin acts the maximum in regards to reducing blood sugar.
- Duration of action – It is the time mentioning the duration of action of insulin in lowering blood glucose.
Based on how quickly the insulin acts, when they peak and on the duration that they last; insulin is classified into different types.
Some of the types of insulin are:-
- Rapid-acting insulin – Action of this type of insulin commences in around 15 minutes post injection. It peaks in around 1 hour and the action continues for approximately 2 to 4 hours. Rapid acting insulin is usually given immediately before the meal or in some cases can be given after the meal. It is generally given in combination with long-acting insulin.
Examples: Insulin glulisine (Apidra), insulin lispro (Humalog), and insulin aspart (NovoLog).
- Regular or Short-acting insulin – This type of insulin reaches the bloodstream in approximately 30 minutes post injection. It peaks around 2 to 3 hours post injection and the action continues for about 3 to 6 hours. Regular acting insulin should be injected 30 to 45 minutes before meals else, it can be taken before a meal.
Examples: Humulin R, Novolin R.
- Intermediate-acting insulin – After injection, this type of insulin reaches the bloodstream in around 2 to 4 hours. It peaks in about 4 to 12 hours and its action continues for around 12 to 18 hours.
Examples: NPH (Humulin N, Novolin N).
- Long-acting insulin – Several hours after the injection, long-acting insulin reaches the bloodstream. It tends to reduce the glucose level evenly over a 24-hour period. It is generally taken in the morning and is used with short-acting or rapid-acting insulin.
Examples: Insulin detemir (Levemir) and insulin glargine (Lantus).
- Pre-mixed Insulin – Onset of action takes place within 30 minutes. It reaches the peak within 2-4 hours and it is effective for 22-24 hours. Pre-mixed insulin is of great help in people having trouble drawing up insulin out of two different bottles. This type of insulin mixes short-acting and intermediate acting insulin and is generally administered two times a day. It is indicated in people with poor eyesight or dexterity. If the insulin mix that is recommended by your physician, fails to be available as a pre-mix then, you shall have to do the mixing yourself.
Examples: Humalog® Mix 75/25, Humalog® Mix 50/50, Humulin® Mix 70/30, Novolog® Mix 70/30, Novolin® Mix 70/30.
- Inhaled insulin – Inhaled insulin commences to work within 12 to 15 minutes. It peaks in around 30 minutes, and is out of the system in 180 minutes.
Examples: Technosphere insulin-inhalation system (Afrezza).
Insulin is accessible in varying strengths. Insulin strength is chiefly dependent on the dosage required by the patient. All types of insulin are available in a form which is dissolved or suspended in liquids which requires to be injected.
Mode of Administration
Insulin cannot be consumed as a pill as the pill would be broken down during digestion. Hence, for the insulin to get into our bloodstream, it must be injected into the fat under the skin. For the fastest delivery, insulin can be injected into the abdomen, for little more slowly into the upper arm and for the slowest delivery into the thigh or buttocks. The needle site for each shot should vary to avoid generating fatty deposits or hard lumps. The number of injections and the type of insulin required shall differ from patient to patient.
There are several methods by which insulin can be delivered. Insulin can be delivered via a needle & syringe; a pre-filled pen; a cartridge system or an insulin pump.
Some of the side effects of insulin administration are as follows:
- Hypoglycaemia (Low blood sugar).
- Weight gain.
- Scars on lumps on site of several injections.
- Allergic reactions.
- Low potassium levels.
Based on the blood sugar levels, the physician may advice combining more than one type of insulin. To decide the type and quantity of insulin required, several factors shall be considered by the physician. Factors such as blood sugar levels, type of diabetes, fluctuation of blood sugar levels and lifestyle of the patient may be considered.
For effective results, insulin should be stored properly. Some of the steps for proper storage of insulin are mentioned below:
- Store the bottle in use at room temperature for 30 days.
- Keep it far from direct sunlight and from extreme temperatures.
- Extra bottles of insulin have to be kept in the refrigerator.
- Do not store the insulin bottle in the freezer. Avoid freezing of insulin.
An insulin pump is a tiny computerized medical device used for the delivery of insulin in the treatment of diabetes mellitus. This method is also known as continuous subcutaneous insulin infusion therapy.
Diabetes Insulin pump helps in effectively managing blood glucose levels
These pumps are small devices, which delivers insulin into the layer of fat, just below the skin. The pump can be programmed to deliver insulin every few minutes in small quantities. It can be programmed to either release small dose of insulin continuously or a bolus dose near mealtime to control the increase in blood sugar post meals.
This delivery system closely mimics the body’s normal release of insulin. The pump is programmed as per the requirements of the user. Only rapid-acting insulin is released into the body through a small, flexible tube.
These pumps reduce the requirement of multiple injections and user can make smaller and much accurate adjustments of insulin delivery. Blood sugar levels can be effectively managed with insulin pump. People suffering with diabetes can wear their insulin pump on their belt or can keep it in their pockets. Several people prefer using this continuous system of insulin delivery over multiple injections.
Components. A traditional pump includes:
- Pump (including controls, batteries and processing module)
- Controls are available to program the insulin and navigate through the menu.
- Screen to depict what your program.
- Battery compartment is there is hold the alkaline battery.
- Disposable reservoir for insulin – Has a cartridge that holds insulin. The reservoir is attached to a cannula at one end. Should be replaced every two to three days.
- Disposable infusion set with cannula and a tubing system to interface insulin reservoir to the cannula – Cannula is inserted with a needle, which is removed after it is placed. It is advisable to change the infusion set every two to three days. Wide range of infusion sets varying in cannula type and length are available. You can choose the set as per your comfort.
How do insulin pumps work?
Insulin pumps continuously transport short-acting or rapid-acting insulin into the body through a catheter, which is placed beneath the skin. Insulin pump sends insulin, stored in a reservoir within the pump, into the body through an infusion set. A tiny flexible thin tube known as cannula is inserted beneath the skin to deliver insulin to be absorbed gradually into the bloodstream.
Depending on the requirement of the patient, different types of insulin doses can be administered. Insulin doses are separated into:
- Basal Dose – Small amounts of insulin are programmed to deliver continuously mimicking the production of basal insulin by pancreas. Programmed rate is decided as per the requirement of the patient. This dose maintains the blood glucose levels within range between the meals and overnight. Different quantities of insulin can be programmed at different times of the day and night.
- Bolus Dose – To compensate for the food that you are going to eat or to rectify the elevated blood sugar levels; additional amounts of insulin can be delivered. The bolus calculators present in the insulin pump helps in calculating the bolus amount based on the requirement of the patient.
- Correction or supplemental Doses – If you have increased levels of blood glucose before eating then you can administer supplemental or correction bolus of insulin to normalize the blood glucose levels.
It is necessary to check your blood sugar levels minimum four times a day, if you use an insulin pump. This shall help you in setting your insulin dose based on your food and physical activity.
Advantages of using an insulin pump:
- Eliminating the need for multiple injections.
- Insulin can be delivered more accurately than injections.
- Delivery of bolus insulin is made easy.
- Provides better HbA1c control.
- Reduces severe attacks of hypoglycemia (low blood sugar).
- Absorption of insulin can be predicted more accurately.
- Permits you to exercise without the need to consume large quantities of carbohydrates.
- Offers ability to change the basal insulin when patient is ill.
- Eradicates erratic effects of long-acting or intermediate-acting insulin.
- Experiences fewer large fluctuations in your blood sugar levels.
- Achieves greater accuracy in reducing increased blood glucose levels.
- Provides better management of blood glucose levels when travelling across time zones.
Disadvantages of using insulin pumps:
- Can give rise to increase in weight.
- Risk of diabetic ketoacidosis due to absorption issues or from pump malfunction may occur.
- Can be cumbersome, as you shall always be attached to a pump.
- Patient may require a hospital stay to be trained in using the pump.
- Constant assessment of blood sugar levels shall be required, to determine the effectiveness of insulin delivery.
- Increased chances of risk of infections from cannula.
- Risk of infusion line getting blocked hence, constant change shall be required.
- Pumps may be quite costly.
- Scar tissues can result at the area around the inserted cannula.
- Allergic reactions and other skin irritations may arise from the adhesives.
How are Insulin pumps worn?
Insulin pumps are small medical device, which can be placed on the belt, waist of trousers or can be kept in the pockets. The pumps are connected to the body through infusion set. The cannula sits over the skin the entire day while the infusion set is placed in the same sites on the body, as are used for injections. It is essential to replace the infusion set once in two to three days. Using a Luer connector, the infusion set is connected to the pump. This is a standard locking mechanism, which securely attached the tube to the pump.
Selecting an Insulin pump
There are several options available when you have to make a choice of an insulin pump. The ‘ideal’ pump differs from person to person. Certain factors, which play a vital role in the selection of an insulin pump, are:
- Cannula insertion angles.
- Easy usage.
- Special features.
Factors concerning the patient related to the selection of infusion set includes:
- Age of the patient.
- Body characteristics.
- Immune system function.
- Physical activities and
- History of Diabetic Ketoacidosis.