What do you know about insulin pumps?

Maria Trimarchi

When do you wear an insulin pump?

Insulin pumps are insulin delivery systems that work 24 hours a day, 7 days a week.

How big is a typical modern insulin pump?

A typical insulin pump isn't as big as you may imagine. Most are shorter than the average smartphone, although they're often a little thicker.

Is it true an insulin pump is the same thing as an artificial pancreas?

Although an insulin pump is a continuous method of delivering insulin, because you still monitor and program your blood glucose levels and make adjustments, it's not the same as the watchful, automated delivery of an articial pancreas.

Insulin pumps deliver insulin around the clock. What's it called when you add a dose at mealtime?

Bolus insulin doses are doses that are extra to the ongoing insulin the pump is delivering (the long-acting "basal" dose), such as adding short-acting insulin at mealtime.

What's an important consideration when choosing a pump?

Whether or not to choose a pump with or without tubing, plus its reservoir volume and its capabilites for flexible dosing are just three important things to look at when considering an insulin pump.

How long do most people keep an insulin pump?

Most people keep an insulin pump for the length of its warranty, which is usually about four or five years.

How much insulin should a pump's reservoir be able to hold?

It varies for each person's individual needs, but most people will find a pump with a reservoir able to hold enough insulin for three days (plus some to prime the tubing) is perfect.

As much as half of your total daily insulin dose is needed to replace what?

As much as 40 to 50 percent of your total daily insulin dose goes toward replacing your body's overnight insulin needs.

What is a cannula?

Insulin pumps are external devices, so for insulin to be infused underneath your skin, it needs a way to get there. And that's where in an infusion cannula comes in to help. A cannula is a thin tube with one end connected to the insulin reservoir inside the pump and the other end under your skin, and they're changed every couple days.

If you're insulin resistant, or you use a lot of insulin in one day, how much should the reservoir of your pump hold?

If you're insulin resistant, or you need large amounts of insulin every day, look for a pump with a reservoir volume of as much as 480 units -- at least one brand makes that an available option.

What type of insulin is used in insulin pumps?

Because of the continuous action, most pumps use rapid-acting insulin -- no matter what type you used before switching to a pump.

Traditional insulin pumps are made up of three main parts, including the pump, the tubing that delivers the insulin and what?

The three main parts that make up a traditional insulin pump are: 1. the pump itself, which contains the insulin reservoir, the programming screen or buttons, and the battery; 2. the plastic tube through which insulin is delivered; and, 3. the infusion set, a Teflon or steel device that attaches to your skin with an adhesive patch. It's usually implanted under your skin in the stomach area, but could also safely be placed on your upper arms, buttocks, hips or thigh.

Of all the people living with uncontrolled blood glucose, which characteristic makes a person a good candidate for using an insulin pump?

It's not type 1 or type 2 that matters when it comes down to whether or not you're a good candidate for an insulin pump. Criteria used to considered whether or not you'll have success with the pump includes uncontrolled blood glucose, and, generally: 1. the desire to lower those numbers and get in control, 2. a willingness to track your food intake and blood glucose levels; 3. the physical, emotional and cognitive ability to manage your insulin pump, or have a caretaker to do so, and 4. a willingness and history of keeping your doctor's appointments.

Which is an important feature to evaluate when choosing an insulin pump?

There are several things to consider when choosing an insulin pump. Depending on which are priorities for you, you may want to evaluate alarms, it's overall appearance and ease of use, cost, data management software, reservoir size and whether or not it's watertight.

In order to program your pump, you need to know what your insulin sensitvity factor is. What is an insulin sensitivity factor?

A person's insulin sensitivity factor is, basically, the number of points just one unit of insulin lowers your blood glucose.

When you use an insulin pump, why is it important to know your insulin-to-carbohydrate ratio?

Your individual insulin-to-carbohydrate ratio is important because you use it to figure out how much insulin you need to bolus before a meal.

When should an insulin bolus be given?

It's important to remember that insulin pumps don't know when or what you're eating. A bolus dose is needed any time you eat foods with more than 5 grams of carbohydrates.

Which feature makes an insulin pump a "smart" pump?

Called "smart," these insulin pumps have colus calculators. Because the user needs to program their insulin-to-carbohydrate ration, smart pumps usually work best for people who count carbohydrates.

Is it true insulin pumps can connect to your personal computer?

Since the 1990s, most pumps can connect to your computer -- or smartphone -- for data backups and managing your pump. And some can be charged with miniUSB.

Which is a benefit of using an insulin pump instead of giving yourself injections?

Using an insulin pump gives you more flexibility in eating and exercising, it delivers more accurate levels of insulin, and it also reduces incidence of low blood sugar -- and many people also feel it's easier to manage their diabetes this way, at least once you get used to it.

If you're switching from a longer-acting to a rapid-acting insulin, it's possible you might start with how much less insulin when you switch to a pump?

To determine how much insulin you'll need for your pump, you take the average of the total units of insulin you use every day, over several days. But people switching from a long-acting to a rapid-acting insulin often find they need about 20 percent less for their pump.

What's the 1800 rule?

There are two rules, actually, the 1500 rule and the 1800 rule. Both are used in calculating your insulin sensitivity factor: the 1500 rule applies to regular-acting insulin, whereas the 1800 rule applies to rapid-acting insulin. The 1800/1500 rules estimate the point drop in mg/dL for every unit of insulin taken.

When might you need to increase your basal insulin rate?

Sometimes our bodies need more or less insulin, independent of diabetes. if you're stressed out, having your period or you're taking corticosteroids, you may need to set a higher rate.

Which is a reason you might need to decrease your basal insulin rate setting?

During times when your insulin will likely be lower -- like when you've been exercising, you're taking a long flight where you'll be inactive for hours, or if you've been sick and unable to eat, lowering your basal rate reflects your need for less insulin.

It's common for blood glucose levels to decrease overnight while you're sleeping. How does an insulin pump help?

Using an insulin pump makes managing overnight hypo easier. Pumps offer alarms to alert you to dips and spike but also allows for you to create a separate program to deliver less insulin overnight.

If you have to disconnect your pump, you should never leave it off for more than how long?

When you disconnect your insulin pump you're not receiving any insulin, so it's important not to go too long before reattaching it -- usually no more than an hour or two, at most.

There are a lot of advantages when switching from insulin injections to using an insulin pump. But which is one of the disadvantages of an insulin pump?

Without some small lifestyle changes, some people find they gain weight when they first start using the insulin pump -- weight gain that's usually caused by the new ease of snacking and eating meals without injections. Additionally, pumps can be bothersome to some people because they're worn at all times. And, depending on the device and insurance, pumps and their necessary accessories can be expensive.

Do you have to remove your pump for bathing, showering or swimming?

Maybe yes, or maybe no. While many pumps are waterproof (some better and longer than others), some aren't and need to be disconnected and removed to keep them dry.

Which is an all-in-one device, a traditional insulin pump or a "patch pump"?

Patch pumps, which are tubeless, are designed as all-in-one devices worn directly on your body. Traditional insulin pumps aren't worn directly on the skin (which is why there's tubing).

What are some insulin pumps able to send to you or to your friends and family?

Some systems are capable of automatically sending text message notifications about your glucose-related events, like if your blood glucose level drops below your target.

Is it true all infusion sets have cannulas that insert at a 90 degree angle?

Most insulin pumps use the same kind of syringe connection, called Luer lock system syringe connectors. But, while some infusion sets (the part of the insulin pump system that connects to your body) require the tube to be inserted straight in, at a 90-degree angle, that's not true for all -- some sets may be inserted at a 30 degree, while others may find a shallow 45-degree angle the most comfortable.

If your insulin pump fails or your insulin isn't delivered properly, ketones can begin building up in just three hours. Ketones are chemical compounds your body makes when it turns what into energy?

If your pump fails to deliver, glucose will begin to build up in your bloodstream. Because it's not available for your body to use as energy, it begins to burn fat, instead. Ketones are normal for everyone, diabetes or not -- but if the amount of ketones in your blood gets to high, as with low insulin and high blood sugar, they can cause blood sugar levels greater than 240 mg/dL, confusion and other dangerous side effects.

What are "CGM" readings?

CGM is the acronym used for continuous glucose monitor system readings (those are your glucose levels). Continuous glucose monitors, which are often used in combination with insulin pumps, monitor your glucose levels in real-time through a small sensor underneath your skin and alert you to spikes and dips so you can make corrective doses.

What is one thing different about an insulin pod or "patch pump" versus a traditional insulin pump?

Patch pumps, such as the Omnipod Personal Diabetes Manager, are pumps that attach to the skin, rather than connect to your body with tubing.

Although an artifical pancreas doesn't yet exist, the concept is based on the combination of three things: a continuous glucose monitoring system, an insulin pump and what?

The concept of the artificial pancreas is a closed-loop monitoring and insulin delivery system, seamless and happening behind-the-scenes to the user because it's run by software rather than the user.

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About This Quiz

Since they were first introduced in the 1970s, insulin pumps have been important devices for treating type 1 -- and, it may surprise you, type 2 -- diabetes. That's right, of the roughly 350,000 Americans using insulin pumps, about 30,000 of them are living with type 2. A lot has changed since backpack-size pumps were the only option.

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