Insulin Delivery – The Latest Recommendations

By Julie Arel posted in Latest Diabetes News Professionals & Educators
Updated

Insulin penPreface

I once helped organize an international diabetes conference for hundreds of leading diabetes educators representing over 10 countries including Canada.  During a general session, the educators were asked if they had ever tried a self-injection.  They answered anonymously with voting buttons.  Astonishingly, well over 80% of the diabetes educators admitted having never inserted an insulin syringe or pen needle in their own body.  Have you?   

A diabetes educator once told me the story of an insulin using patient who came into her office on a routine visit.  The educator asked the patient to demonstrate an insulin injection.  The patient went on to dial her dose, prime her pen, and insert the pen needle into her skin.  And, then, oddly, she spun the pen around, on the injection site, with the needle still in her body.  When asked to describe what she was doing, the patient explained she was rotating the injection site!  Clearly something got lost in translation along the way!

Overview

This article will briefly address ways to overcome the fear of insulin delivery into one’s body.  It will summarize the latest delivery recommendations to help ensure your patients experience comfortable and safe injections, using the latest techniques supported by research with the devices appropriate for their needs.

Alleviate the Fear of the Needle Before It Is Needed

Because diabetes is a progressive disease it is wise to inform patients that they may likely need insulin at some point in the future.  Because of this progression, it is also prudent never to threaten patients into treatment compliance with the threat of injections as they will see their insulin initiation as a personal failure, not a natural progression of their disease.[i]

The fear and dread of injections can lead to patients with type 2 diabetes and their health professionals to delay insulin initiation beyond the time at which it is clinically appropriate.  As such, it is important to address patients’ (and even one’s own) fears early on, before insulin is needed.[ii]  The educators who participated in the meeting mentioned in the preface segment of this article were each given an injection pen and a pen needle and encouraged to try inserting the needle in their own body, there and then in the session.  Seeing their fellow educators doing it, together with a little peer pressure, the great majority of them went on to prick themselves – and were relieved to find out that injections really don’t hurt!  Encouraging patients to do the same can help them alleviate their fear as well and reduce resistance to insulin initiation down the road.

Patients are in Luck – Shorter Needles Do It Best

Luckily for patients, technology has greatly improved over the years.  Needles are now shorter, thinner, and offer new pen attachment options.  These innovations provide greater patient comfort, safety, and ease than older technology devices.


Snap 2014-01-17 at 15.05.35Research demonstrates that the shorter needles deliver insulin consistently into the subcutaneous tissue and minimize the risk of intramuscular injections.  Most adults’ skin thickness is between 1.9-2.4mm therefore even the shortest 4mm, 5mm, and 6mm needles safely deliver insulin into the sub-cutaneous tissue. [iii]

So, while skin thickness is similar from one person to another, the amount of sub-cutaneous tissue varies widely from person to person and from one injection site to another.  The depth of injection within the subcutaneous tissue doesn’t seem to impact leakage rate, absorption rate or HbA1c so even patients with generous amounts of sub-cutaneous tissue benefit from the shorter needles.  Needles longer than 8mm increase the risk of intramuscular injections which can lead to an unpredictable speed of insulin action.  Therefore, there should be no need to recommend these longer needles.[iv]

Needle Gauge and Attachment

In terms of diameter, the larger the gauge number, the smaller the diameter of the needle; 32G is thinner than 30G for example.   Because thin gauge pen needles feature technology allowing insulin to easily flow through the needle, these are appropriate for most patients.  However, for patients who inject large dose volumes or have limited manual dexterity and strength, it may be more comfortable, faster and take less manual strength to inject with larger diameter needles which feature larger inner diameters than their thin needle counterparts. [v]

Patients with arthritis, other manual dexterity issues, or vision impairments may find that pen needles with a click-on attachment and an audible “click” to confirm that the needle is well seated on the pen are easier to use than the traditional pen needles with screw-on attachment. [vi]

Pen Systems

To inject the correct dose, priming should be performed before each injection according to injection pen instructions.  Patients should ensure that there are no air bubbles in the pen.  To remove air bubbles, the pen should be held upright with needle facing up, then the barrel can be tapped to send the bubbles to the top and then the pen needle primed to expel the air bubbles.  To avoid leakage out of injection site, patients should inject slowly and then hold the needle in skin for 10 seconds after injection. [vii]  This is particularly important when injecting large dosages.

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Tips for a Comfortable Injection

  • Rotate injection site regularly
  • If using alcohol swab wait for alcohol to be completely dry
  • Avoid damaged skin and areas with lipohypertrophy
  • Use shorter, thinner needles
  • Use needle only once
  • Inject medication at room temperature
  • Insert the needle quickly; do not change direction of the needle during insertion or withdrawal from the skin
  • Inject slowly

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The Good Old Syringe

While syringes represent an older technology, they offer certain advantages over pens systems.  They are typically less expensive, allow for the mixing of insulins, and can be used with all types of insulins.

First, one must ensure is that the syringe is designed for use with U-100 insulin concentration to match the insulin that is prescribed. The next selection criterion is based on dose size.  Just like a measuring cup, it is easiest to dose the medication volume in the smallest capacity syringe possible for that dose size.  Doses of 30 units or less should be injected with a 3/10cc syringe (maximum dose 30 units), 50 units or less should be injected with a 1/2cc syringe and 100 units or less with a 1cc syringe.  Some 3/10cc syringes have half unit markings, which are particularly helpful for those who need to dose in half unit increments.

While we’re at it, let’s be reminded that for easier dosing, it is recommended to draw up air in the syringe and inject it into the insulin vial; this makes the insulin is easier to draw out from the vial.   Once the insulin is in the syringe, it is important to hold the syringe upright and tap the barrel to move air bubbles to the top, then push plunger to expel the air out through the needle.

Techniques – To Pinch or Not to Pinch

Selecting injection technique focuses primarily to ensure delivery of insulin into the subcutaneous tissue consistently and thus avoiding intramuscular injections.  The technique chosen is primarily based on needle length used and amount of subcutaneous tissue at the injection site.

For most patients, shorter 4, 5, and 6mm needles allow the use of the easier one-handed “no pinch” (without skin fold) technique where  the needle is inserted into the subcutaneous tissue at a 90° angle relative to the skin.  However, even with these shorter needles, this “no pinch” technique may require a 45° angle relative to the skin for children, slim patients and injection sites with thin sub-cutaneous tissue. [viii]

For people using longer needles such as 8mm and 12mm, the two hand “pinch” technique (also known as the “skin lift” or “with skin fold”) should be used.  This is particularly applicable to syringe users because commonly available syringes only come in these longer lengths.  In some cases, a 45° angle may be needed with this technique to further minimize the risk of intramuscular injections. [ix] Please see Figure A for a visual of injection techniques as they relate to the subcutaneous tissue.

Figure A:  Correct injection techniques into the subcutaneous tissue.
Image courtesy of Ypsomed AG.

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Cleanliness

Patient hands, injection sites and cartridges or vials should be clean when performing an injection.  If they aren’t it is recommended to use soap and water to clean hands and injection site.  If alcohol is used, as it is often recommended in institutional or home care setting, the alcohol should be dry before injecting to minimize injection discomfort. [x]

Insulin Considerations

Insulin vials, cartridges, and pre-filled pens should be refrigerated until opened.  Once opened, they can be stored at room temperature.  Insulin should not be used past its expiration date or for a little less than a month after opened – the package inserts have more information on this.  It is best to inject at room temperature for greater injection comfort.  Cloudy insulin must be re-suspended before each injection by rolling the pen, vial or cartridge ten times then tipped ten times until it has a uniformly white appearance.[xi]

Using Needles Once – Is That Really Necessary?

Manufacturers say to use pen needles only once.  Is it just a self-serving message to sell more needles?  No.  For one thing pen needles are designed and approved for single use.  Nevertheless, there are many other reasons why needles should only be used once.  Today’s needles are finer and thinner than ever, so using them only once may reduce the risk of burred, dull, and broken needles which can be more painful and lead to lipohypertrophy.   Re-using pen needles also strips away the silicone coating which further contributes to painful injections.  Single use also reduces the risk of clogged needles because left over insulin in the cannula can crystalize in the needle and block it.  In addition, if left on an injection pen, insulin can leak out and lead to inaccurate dosing later and, in the other direction, leaves the door open for contaminants to enter the cartridge.[xii]  Finally if that doesn’t cause one to pause, imagine a used Q-tip®, would one use that again?  No!  Then why put a used needle back in one’s body?

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Site Selection & Rotation

Research shows that insulin is absorbed fastest and consistently in the abdomen; which generally makes it the preferred injection site.  The buttock has the slowest absorption site.  The upper arm and side of thigh are somewhere in the middle in terms of speed.  If desired, the site can be chosen for each insulin injection based on the desired speed of action. [xiii]

In order to avoid lipohypertrophy (damaged tissue or a buildup of scar tissue) and to ensure consistent absorption of medication, it is critical to rotate injection sites with each injection.  Patients should be thought to inspect their injection site for signs of lipohypertrophy and damaged skin and avoid injecting in those areas because insulin absorption can be unpredictable if injected those areas.[xiv]

Examples of lipohypertrophy.
Photos courtesy of Ypsomed AG.

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A “structured rotation” technique is generally recommended to keep injection sites health.  For example, if injecting in the abdomen, injection number one could be made to the upper right hand side of the belly button, injection number two would be made to the lower right of the belly button, the third to the lower left and fourth to the upper left. Within each one of these areas, further rotation should be implemented, with injections sites at least 2-3cm (2 fingers) apart.  Remember to stay at least 3cm away from the belly button when injecting in the abdomen.[xv]

Needle Disposal

To prevent accidental needle sticks, needles should not be re-capped and then placed immediately into sharps containers.  Sharps container should be disposed of according to local ordinances.  Both health professionals and patients should know the local rules for disposal.

Summary

It is important to address the fear of injections well before a patient needs to be initiated to insulin.  Addressing this fear early on and encouraging a trial injection can help alleviate this fear.

A periodic check of patient injection technique helps ensure they benefit from safe and comfortable injections using of the right technique and devices for their needs.  For consistent and predictable speed of action it is critical that insulin is delivered within the subcutaneous tissue.  The no-pinch technique at a 90° angle in combination with the shorter length needles is appropriate for most patients.  Some patients like children and thin adults or where injections in areas have thin subcutaneous tissue, the pinch-up technique and/or a 45° angle may be needed.  Site rotation is critical to avoid lypohypertrophy and if lypohypertrophy is present injections should be avoided in this area.  For comfortable injections, insulin should be injected at room temperature, the needle should be inserted quickly and insulin injected slowly

References


[i] Meece J. Dispelling myths and removing barriers about injectable therapy in type 2 diabetes. The Diabetes Educator 2006; 32: 95-185

[ii] Meece J. Dispelling myths and removing barriers about injectable therapy in type 2 diabetes. The Diabetes Educator 2006; 32: 95-185

[iii] Gibney MA, Aarce CH, Byron KJ, Hirsch LJ. Skin and subcutaneous adipose layer thickness in adults with diabetes

at sites used for injectable therapy injections: Implications for needle length recommendations. Current Medical Research and  Opinion

2010; 26: 1519-1530.

[iv] Gibney MA, Aarce CH, Byron KJ, Hirsch LJ. Skin and subcutaneous adipose layer thickness in adults with diabetes

at sites used for injectable therapy injections: Implications for needle length recommendations. Current Medical Research and  Opinion

2010; 26: 1519-1530.

[v] Guide to Choosing Your Pen Needle. Clickfine Pen Needles website. http://www.myclickfine.com/learning-center/choose-pen-needle.html. Accessed December 5, 2013.

[vi] Guide to Choosing Your Pen Needle. Clickfine Pen Needles website. http://www.myclickfine.com/learning-center/choose-pen-needle.html. Accessed December 5, 2013.

[vii] Annersten M, Frid A. Injectable therapy Pen Devices dribble from the tip of the needle after injection. Practical Diabetes International 2000; 17: 109-111.

[viii] Hirsch L, Klaff L, Bailey T, Gibney M, Albanese J, Qu S, Kassler-Taub K. Comparative glycemic control, safety

and patient ratings for a new 4mm X 32 G insulin pen needle in adults with diabetes. Current Medical Research and Opinion 2010; 26: 1531-1541.

[ix] Hirsch L, Klaff L, Bailey T, Gibney M, Albanese J, Qu S, Kassler-Taub K. Comparative glycemic control, safety

and patient ratings for a new 4mm X 32 G insulin pen needle in adults with diabetes. Current Medical Research and Opinion 2010; 26: 1531-1541.

[x] Gorman KC. Good hygiene versus alcohol swabs before injectable therapy injections (letter). Diabetes Care 1993;16: 960-961.

[xi] Strauss K, De Gols H, Letondeur C, Matyjaszczyk M & Frid A. The Second Injection Technique Event (SITE),

Barcelona, Spain. Practical Diabetes International 2002; 19(1):17-21

[xii] Recommendations for Best Practice in Injection Technique. Forum for Injection Technique Canada website. http://www.fit4diabetes.com/files/9813/3940/7687/FIT_Recommendations_2011.pdf. Accessed December 5, 2013.

[xiii] Zehrer C, Hansen R, Bantle J. Reducing blood glucose variability by use of abdominal insulin injection sites. Diabetes Educator 1990; 16:6:474-77.

[xiv] Strauss K, De Gols H, Letondeur C, Matyjaszczyk M & Frid A. The Second Injection Technique Event (SITE),

Barcelona, Spain. Practical Diabetes International 2002; 19(1):17-21

[xv] Recommendations for Best Practice in Injection Technique. Forum for Injection Technique Canada website. http://www.fit4diabetes.com/files/9813/3940/7687/FIT_Recommendations_2011.pdf. Accessed December 5, 2013.

 

About the Author
Julie Arel

Julie Arel is a marketing and project management professional who has developed, marketed, and sold insulin delivery devices and other diabetes care products internationally for 22 years. If you have any comments on this article or have questions for Julie, contact her at areljulie@sympatico.ca or connect with her on LinkedIn