Patient Care

EMS Treatment of the Type 1 Diabetic Insulin Pump User

Issue 9 and Volume 40.

As an EMT, running calls for a Type 1 diabetic patient who’s unresponsive is common. The reasons are endless: too much insulin, no food, too much exercise, stressed, feeling sick and so on—responding EMS providers usually don’t have a sure answer as to why the patient is in their current condition.

However, much like many aspects of EMS, technological advancements have helped. Insulin pumps are some of the most recent advancements in diabetic treatment. They not only aid the patient in tighter control of their diabetes, but can also aid first responders in their ability to treat the patient.

Background

Type 1 diabetes is an ever-growing medical condition. In 2012, 29.1 million people in the Unites States (9.3% of the population) had been diagnosed with diabetes. Of those, 1.25 million (5%) had Type 1 diabetes. Still, an estimated 8.1 million people had undiagnosed diabetes of some form. That year, diabetes patients cost the healthcare system $245 billion.1

With numbers like these, providers should become proactive in learning the newest methods in managing Type 1 diabetes. The world is working for a cure, on better treatments and better methods of control. As first responders, learning these new methods can help this population of patients and assist in removing diabetes as the seventh leading cause of death in the U.S.1 One step in achieving this is to understand the functions of insulin pumps.

Pump Mechanics

Insulin pumps came about in the 1970s and looked very different than they do now—the first pumps were the size of backpacks. Just five years ago most pumps could only dispense insulin in 1-unit measurements. Today, most pumps are able to dispense as little as 0.10 units, and they’ve had a dramatic redesign. They now resemble a modern smartphone in size and appearance, each with a plethora of information and treatment capability. (See Figure 1.)

Figure 1: Insulin pump

Insulin pumps secrete short-acting insulin over a 24-hour period with no need to use long-acting insulin. They also reduce the daily injections normally required to help maintain normal blood glucose levels from several to one. The insulin pump is attached subcutaneously using a catheter much like an IV; a needle punctures the skin and, when removed, a catheter is all that remains. The site is changed every three days on average, depending on how much insulin the user requires—most pumps hold 300 units of insulin.

The internal mechanics of the pump are quite simple. A reservoir is filled with insulin, which is drawn up from a vial in the same method one would draw up medication to administer to a patient via a syringe. The reservoir is then inserted into the pump where a plunger has been rewound to accept the recently filled reservoir. A tubing line is attached to the reservoir’s other end. On this end of the tubing, there’s a quick-disconnect release that allows the catheter to remain while the pump and tubing are removed. This allows the pump to be removed while the patient is taking a shower, or doing any activity that may cause harm to the pump. Patients can then reattach the tubing line (I refer to this mechanism as a “twist lock,” due to the twisting action that is required to lock and unlock the tubing). The patient then primes the pump, removing all air from the tubing line.

Now the patient is all set with upwards of 300 units of insulin to administer as needed. The units are dispensed into the body using both basal and bolus rates. A bolus rate is given whenever the patient ingests food or drink. A basal rate is a set amount of insulin that’s been determined with the help of an endocrinologist to be dispensed at set times throughout the day, acting much like long-acting insulin. (See Table 1.)

Table 1: Basal rate schedule

Between the two rates a patient will receive insulin in a very similar manner to a pancreas. With the close mimicking of a pancreas, users can obtain a tighter control of their blood glucose level (BGL) and thus a lower hemoglobin A1C level (average BGL over a three-month period). A lower A1C level is key in lowering the long-term health issues that so commonly accompany Type 1 diabetes.

How Pumps Treat Patients

A common treatment for Type 1 diabetics is referred to as “carb counting.” In this treatment the patient is given a set amount of insulin to administer for a set amount of carbohydrates, also known as a sliding scale. For example, I may be instructed to take 1 unit of insulin for every 25 grams of carbohydrates, so if I were to eat 100 grams of carbohydrates I would need to take 4 units of insulin.

After figuring out the insulin requirements for food, we need to see where our BGL is. A BGL reading is a starting point; from here we must take insulin to adjust our BGL to the correct target range. Very similar to the sliding scale used on carbohydrates, this too uses a required amount of insulin to achieve correct results. This is referred to as the “correction factor.”

Let’s say our patient’s target range lies between 80–120 mg/dL, and their correct amount is 1 unit for every 20 mg/dL over the target range. Our patient now tests their BGL and the reading is 180 mg/dL. The patient is 60 mg/dL over the target range and thus must refer back to their correction amount, which is 3 units. We can now pair the correct amount with the 4 units needed to cover the food and the patient has their needed total: 7 units.

This is a recurring event every time a Type 1 diabetic eats. It takes time and effort, and is an utter inconvenience, especially if this action results in an injection of insulin.

Info for EMS

Even with an insulin pump’s tighter control of blood glucose levels, some Type 1 diabetic patients will still have emergencies. As EMTs and paramedics we’ve been taught a set of basic skills to help diabetic patients, the first being obtaining a BGL. If the patient is responsive they receive oral glucose, or if they’re unresponsive a line of D50 is started. ED transport is determined after the patient awakens. However, with the advancement of insulin pumps, the EMT is now able to tell the patient why their insulin levels dropped.

An insulin pump stores a great deal of information for the user who’s wearing it. Paired with a continuous glucose monitor (CGM), the information becomes even more in depth. A CGM is a small device that’s worn in conjunction with the insulin pump to send continuous BGL readings every five minutes to the insulin pump. (See Figure 2.) The CGM uses the same concept as the pump to attach to the patient’s skin—it’s basically a small sensor that’s inserted under the skin and receives readings from tissue fluid. The device still requires 1–3 BGL readings from an actual glucose meter to provide a calibration, but can then provide multiple reports such as a 12-hour average, a 24-hour average, readings every five minutes, a high and low BGL indicator, bolus and basal alerts, and even computer upload capabilities. All of these are at the EMTs fingertips to be viewed while on scene with the patient.

Figure 2: Continuous glucose monitor



Most current pumps have a very basic button layout: a bolus button, accept button, escape button, and an up, down and light button. (See Figure 3.) This layout makes all the features of the pump easily accessible. It’s reasonable for someone who’s unfamiliar with an insulin pump to be quite nervous trying to access information from one, but learning how to use one or even how to disconnect one is fairly easy.

Figure 3: Menu buttons on a Medtronic MiniMed insulin pump

A common fear among first responders is that a mere touch of any button will activate the pump’s insulin delivery system. However, most pumps have built-in safeguards that prevent an unwanted action from occurring with just one button push. They require you to acknowledge the request and then submit it once more prior to the insulin being injected.

The main buttons are the bolus, accept and escape buttons. The easiest way to view these buttons is to simply look at their titles. The bolus button will give you a shortcut to delivering a quick amount of insulin, say when you’ve just sat down to eat some pizza. The accept button will take you forward in the pump’s menu, acting like a submit button, where escape will take you back. To access a patient’s info, simply move through a few prompts on the pump’s screen to select the category you’d like to view.

To disconnect the pump from a patient you go through the pump’s categories and select the “suspend” option. If you’re unfamiliar and uncomfortable with that option, you can use a set of trauma sheers and cut the tubing. The last option would be to disconnect the tubing from the insertion site using the twist lock. All three options are effective and dependent on situational circumstances.

Conclusion

In 45 years, the treatment for Type 1 diabetics has come from large, simple machines with little-to-no patient personalization to personalized state-of-the-art devices. There will undoubtedly be an increase in Type 1 diabetes in the coming years, but there will also be an increase in advancements for treating the disease. Staying up-do-date on new advancements will improve your ability to assess and treat Type 1 diabetics, and by reporting to the nurse or doctor as to why their sugar may have dropped will benefit the patient’s care and improve their ability to recover.

For more information on treating diabetic patients, read “Highs & Lows: Recognizing & treating hypoglycemia, hyperglycemia & other diabetes-related health problems,” by W. Ann “Winnie” Maggiore, JD, NREMT-P, in the December 2013 issue.

Reference
1. American Diabetes Association. (May 18, 2015.) Statistics about diabetes. Retrieved July 29, 2015, from www.diabetes.org/diabetes-basics/statistics/.