Defining the ideal injection techniques when using 5-mm needles in children and adults

New ex vivo method to objectively assess insulin spatial subcutaneous dispersion through time during pump basal-rate based administration

Glycemic variability remains frequent in patients with type 1 diabetes treated with insulin pumps. Heterogeneous spreads of insulin infused by pump in the subcutaneous (SC) tissue are suspected but were barely studied. We propose a new real-time ex-vivo method built by combining high-precision imaging with simultaneous pressure measurements, to obtain a real-time follow-up of insulin subcutaneous propagation. Human skin explants from post-bariatric surgery are imaged in a micro-computed tomography scanner, with optimised parameters to reach one 3D image every 5 min during 3 h of 1UI/h infusion. Pressure inside the tubing is recorded. A new index of dispersion (IoD) is introduced and computed upon the segmented 3D insulin depot per time-step. Infusions were hypodermal in 58.3% among 24 assays, others being intradermal or extradermal. Several minor bubbles and one occlusion were observed. IoD increases with time for all injections. Inter-assay variability is the smallest for hypodermal infusions. Pressure elevations were observed, synchronised with air bubbles arrivals in the tissue. Results encourage the use of this method to compare infusion parameters such as pump model, basal rate, catheter characteristics, infusion site characteristics or patient phenotype.

Needle-free injection of basal insulin improves fasting glucose variability as assessed by continuous glucose monitoring in T2DM: a prospective randomized multicenter open-label crossover study

BACKGROUND

Fasting glucose variability (FGV) extensively promotes the onset and development of diabetic complications. This study aimed to evaluate the FGV in type 2 diabetes mellitus (T2DM) patients administered basal insulin using a needle-free insulin injector (NFII).

RESEARCH DESIGN AND METHODS

This was a prospective randomized multicenter open-label crossover study. We randomly assigned 48 T2DM patients to receive basal insulin by NFII or conventional insulin pen (CIP) for 7-14 days and were then crossed over after washout. We conducted continuous glucose monitoring to investigate the FGV, our primary outcome was a composite parameter of the FGV with a fasting blood glucose target between 4.4 and 6.1 mmol/L.

RESULTS

The coefficient of variation for sensor glucose at 6 a.m. with CIP was 11.67 (8.70,14.81)% vs. 9.48 (6.48,12.24)% with NFII (p = 0.003), and the coefficient of variation for mean sensor glucose at 5-6 a.m. with CIP was 12.70 (9.17,16.56)% vs. 9.23 (7.01,11.98)% with NFII (p < 0.001). The overall basal insulin dosage with CIP injection was 18.00 (16.00, 20.00) IU vs. 16.00 (12.00, 19.00) IU during NFII (p < 0.003).

CONCLUSION

Compared with CIP, the use of the NFII to inject basal insulin improved FGV in T2DM.

CLINICAL TRIAL REGISTRATION

https://www.chictr.org.cn Identifier is ChiCTR2000034674.

Abdominal skin subcutaneous fat thickness over the gestational period in Korean pregnant women: a descriptive observational study

Purpose

Although insulin is usually injected into the abdominal subcutaneous fat, in pregnancy women tend to avoid abdominal injections due to concern about fetal damage. Prior studies have been limited to only measuring skin-subcutaneous fat thickness (S-ScFT) at one site at specific pregnancy points. This study aimed to measure S-ScFT across several abdominal sites and over the gestational period in Korean pregnant women. This can identify which site would be relatively safe for subcutaneous injection during pregnancy.

Methods

Healthy women over 24 weeks of pregnancy in Korea were invited to voluntarily participate in this descriptive study. For the 142 women, S-ScFT of 12 sites in the abdomen were measured by ultrasound, several times over the pregnancy. Each incidence was treated as a case and a total of 262 cases were analyzed.

Results

The mean S-ScFT during pregnancy was 1.14±0.47 cm (1.25±0.54 cm at 24⁺⁰–27⁺⁶ weeks; 1.17±0.48 cm at 28⁺⁰–31⁺⁶ weeks; 1.09⁺⁰.40 cm at 32⁺⁰–35⁺⁶ weeks; and 1.06±0.47 cm at 36⁺⁰–40 weeks of pregnancy). Most S-ScFT were thicker than 10 mm. But S-ScFTs in the lateral abdomen and some sites were suboptimal (<6 mm), especially in the pre-pregnancy underweight body mass index group, who had a high rate of suboptimal thickness (27.1% overall and 33.9% in the lateral side).

Conclusion

The whole abdomen seems to be appropriate for subcutaneous injection in most Korean women during pregnancy, with a 4 to 5-mm short needle. However, for the lateral abdomen, making the skin fold might be needed for fetal safety.

Competency of Prefilled Insulin Pen Usage Among Diabetes Patients in Saudi Arabia: A Cross-sectional Study

BACKGROUND

Correct insulin injection practice is essential for better diabetic control. The aim of this study is to investigate the level of competency of prefilled insulin pen usage (injection technique and storage) among diabetes patients in Saudi Arabia.

METHODS

A cross-sectional survey between March 2017 to July 2017 of randomly selected patients with diabetes attending Diabetes Treatment Center, Prince Sultan Military Medical City, Saudi Arabia, who are actively using a prefilled insulin pen, were interviewed to complete a pre-structured questionnaire to assess the competency of using the insulin pen. The contents of the questionnaire addressed the 6 competency components according to manufacturer recommendation (priming, count time, storage, using new needles, a store with no needles, and discard date), background, clinical and metabolic data. Results of the questionnaire were analyzed to identify common pitfalls and were also contrasted with background clinical and metabolic data.

RESULTS

165 patients with diabetes (aged 14-70yrs) were interviewed for the study and all questioners completed properly. Only 14 (8.5%) patients were following all of the six competency components. Count time 52 (31.6%) was the least followed competency component of the six, whereas discard date and storage of insulin pen were the most followed with 165 (100%) and 159 (96.4%), consecutively. Education was the only significant variable related to the following more than 3 of the competency components, and logistic regression showed the college or higher educated patients to be three times more likely follow more than 3 of the competency components.

CONCLUSION

The study concluded that majority of patients are either ignoring or unaware of the major components of correct use of prefilled insulin in Saudi Arabia.

Pediatric Insulin Injection Technique: A Multi-Country Survey and Clinical Practice Implications

INTRODUCTION

The 2015 Insulin Injection Technique Questionnaire survey involving 13,289 patients included 898 (6.8%) patients in the pediatric age range (≤ 18 years).

METHODS

The younger patients included in the questionnaire survey were grouped according to age: Group 1 (G1), 0-6 years, n = 85; Group 2(G2), 7-13, n = 423; Group 3 (G3), 14-18, n = 390. The injection technique was evaluated by means of a questionnaire and nurse assessment.

RESULTS

Nurses found lipohypertrophy at injection sites in 41.3, 45.2, and 47.3% of patients in G1, G2, and G3, respectively. Unexpected hypoglycemia was common, ranging from 23.8 to 48.1% of patients, and glucose variability was even more common (61.0% in G1, 45.9% in G2, and 52.5% in G3); both conditions were associated with lipohypertrophy. While increasing numbers of patients were using the recommended 4-mm needles, large percentages still used longer ones (33.3% in G1, 45.9% in G2, and 61.5% in G3). The reuse of needles was also common, ranging from 21.1 to 32.5% in the three age groups. Excessive reuse, defined as using a single needle more than five times, was reported by 9.4-21.8% of patients in the three age group. The percentages of patients who had not received any injection training in the last 12 months ranged from 21.2 to 26.8% in the three groups.

CONCLUSION

Implications of our study are as follows: (1) pediatric patients should use 4-mm pen needles or 6-mm syringes (inserted at a 45° angle); (2) patients aged ≤ 6 years should always inject into a raised skin fold regardless of which device is used; (3) all patients should rotate sites and use needles only once to avoid lipohypertrophy.

FUNDING

Becton-Dickinson (BD) diabetes care.

Efficacy, safety and acceptability of the new pen needle 34G × 3.5 mm: a crossover randomized non-inferiority trial; AGO 02 study

OBJECTIVE

Insulin injection aspects, such as fear of injection and pain, directly affect glycemic control, patient adherence and quality of life. Use of thinner and shorter needles could increase acceptance of injections. The aim of the study is to evaluate the non-inferiority of the new 34G × 3.5 mm needle compared to a 32G × 4 mm in patients with diabetes treated with insulin.

METHODS

This is an open, randomized, two-period crossover, non-inferiority trial. Every treatment period lasted 3 weeks. Patients with type 1 or type 2 diabetes, treated with multiple daily insulin injections, were randomly assigned to receive a 34G × 3.5 mm or a 32G × 4 mm pen needle. The primary endpoint was the non-inferiority of the 34G × 3.5 mm in comparison with the 32G × 4 mm pen needle in terms of percentage absolute change of blood fructosamine (% |ΔFru|), using a non-inferiority margin of 20%.

RESULTS

Overall 77 patients were randomized and 73 completed the study. Patients characteristics were: 52% male, 80.5% affected by type 1 diabetes, mean age 52 years (±14.6), mean BMI 24.5 kg/m² (±5.6), HbA1c 8% (±1.1) and baseline fructosamine level 350 µmol/l (±84). Mean fructosamine levels increased by 0.56 µmol/l with the 34G needle, while a reduction of 7.29 μmol/l was documented with the 32G needle. The difference between the two groups (7.84 μmol/l) was not statistically significant (p = .27). The % |ΔFru| between the two groups was 7.55% (95% CI 5.67-9.44), meeting the non-inferiority criterion. Glycemic variability, expressed as standard deviation of fasting blood glucose and post-prandial glucose, was not different between the two treatment groups (p = .63 and p = .77, respectively).

CONCLUSIONS

The 34G × 3.5 mm needle was non-inferior to the 32G × 4 mm needle regarding fructosamine levels and glycemic variability supporting the suitability of the 34G × 3.5 mm needle for insulin injection in patients with diabetes.

CLINICAL TRIAL REGISTRATION

NCT02690467.

Optimal Design of Needle Array for Effective Drug Delivery

Recently, the multi-needle drug injection has been adopted to overcome the shortcomes of conventional single-needle injection, enhancing the efficiency of drug delivery. However, the effect of needle array on the efficacy of drug delivery has not been fully elucidated. In this study, the interactions of drug analogous solution injected from a pair of needles were analyzed to examine the design criteria of effective multi-needle devices for drug delivery. Temporal and spatial variations of relative contents of the solution in the tissues were compared according to the distance between two adjacent needles (DN). As the DN increases from 5 to 20 D, where D is the needle diameter, the solution from each needle encounters 3.5 times faster, and 4.22 times more solution was accumulated. At the same time, the effective spreading area was continuously increased from 54.2 to 177.8 mm² and RCS gradient decreases from 0.087 to 0.037, due to the overlapping effect of the spreading solution from neighboring needles. Finally, based on the experimental results, an optimal design criterion of needle array for effective drug delivery was proposed. The present results would be helpful in the design of multi-needle injection devices and eventually offer advantage to patients with effective drug delivery.

Ultrasound-guided measurement of skin and subcutaneous tissue thickness in children with diabetes and recommendations for giving insulin injections

Aim

To measure skin thickness (ST) and skin + subcutaneous layer thickness (SCT) by ultrasound and estimate the risk of intramuscular injection (IM) with different needle lengths across injection sites according to age group.

Method

Children recruited between 1 and 18 years with type 1 and 2 diabetes on insulin injections and divided into three age groups: 1–6 years, 7–12 years and 13–18 years. A portable ultrasound was used to measure ST and SCT at four injection sites on the abdomen, arm, thigh and buttock.

Results

Total 153 children enrolled for the study. The mean (SD) measurement of ST & SCT at four sites on abdomen, arm, thigh & buttocks were as follows; 4.33 mm (±2.22), 5.55 mm (±2.26), 5.83 mm (±3.12), 6.48 mm (±3.47) in 1–6 years old; 7.11 mm (±3.68), 7.79 mm (±4.54), 7.17 mm (±3.62), 8.51 mm (±3.65) in 7–12 years old; 8.94 mm (±4.50), 8.42 mm (±5.00), 8.61 mm (±4.76), 9.76 mm (±4.38) in 13–18 years old. Young children, 1–6 years have the highest risk of IM injection with all needle lengths, i.e. 4, 5, 6, 8 & 12.7 mm, while older children 7–12 & 13–18 years have a lower risk with shorter needles (4, 5 and 6 mm) as compared to longer needles (8 and 12.7 mm).

Conclusions

Children with diabetes on insulin therapy should be advised on the appropriate needle length accordingly to their age and BMI.

Factors Affecting the Absorption of Subcutaneously Administered Insulin: Effect on Variability

Variability in the effect of subcutaneously administered insulin represents a major challenge in insulin therapy where precise dosing is required in order to achieve targeted glucose levels. Since this variability is largely influenced by the absorption of insulin, a deeper understanding of the factors affecting the absorption of insulin from the subcutaneous tissue is necessary in order to improve glycaemic control and the long-term prognosis in people with diabetes. These factors can be related to either the insulin preparation, the injection site/patient, or the injection technique. This review highlights the factors affecting insulin absorption with special attention on the physiological factors at the injection site. In addition, it also provides a detailed description of the insulin absorption process and the various modifications to this process that have been utilized by the different insulin preparations available.

The Faces Emotional Coping Scale as a self-reporting instrument for coping with needle-related procedures: An initial validation study with children treated for type 1 diabetes

The aim of this study was to determine the concurrent and content validity, sensitivity and inter-rater reliability of the Faces Emotional Coping Scale (FECS) to evaluate the children's anticipation of the level of emotional coping in conjunction with a venepuncture. A total of 153 children with type 1 diabetes and 86 of their parents participated in the study. The age of the children, 76 of whom were boys, ranged from 7 to 18 years. The child and his or her parent reported the child's coping ability, and the child reported the pain intensity and unpleasantness of a venepuncture. The child also wrote a short narrative about his or her experience of the needle procedure. The FECS correlated negatively with the Coloured Analogue Scale and the Facial Affective Scale and positively with the FECS by proxy. The narratives of 90 children correlated negatively with the FECS. Younger children reported significantly lower scores than older children did regarding their ability to cope with a venepuncture. The children's scores on the FECS showed good agreement with the parents' scores. In this study, the FECS was deemed valid for measuring children's ability to cope with their emotions when undergoing needle-related procedures like venepuncture.

Effective method for drug injection into subcutaneous tissue

Subcutaneous injection of drug solution is widely used for continuous and low dose drug treatment. Although the drug injections have been administered for a long time, challenges in the design of injection devices are still needed to minimize the variability, pain, or skin disorder by repeated drug injections. To avoid these adverse effects, systematic study on the effects of injection conditions should be conducted to improve the predictability of drug effect. Here, the effects of injection conditions on the drug permeation in tissues were investigated using X-ray imaging technique which provides real-time images of drug permeation with high spatial resolution. The shape and concentration distribution of the injected drug solution in the porcine subcutaneous and muscle tissues are visualized. Dynamic movements of the wetting front (WF) and temporal variations of water contents in the two tissues are quantitatively analyzed. Based on the quantitative analysis of the experimental data, the permeability of drug solution through the tissues are estimated according to permeation direction, injection speed, and tissue. The present results would be helpful for improving the performance of drug injection devices and for predicting the drug efficacy in tissues using biomedical simulation.

In-Hospital Administration of Insulin by Nurses in Northern Greece: An Observational Study

OBJECTIVE

The purpose of this study is to explore current practice regarding insulin administration by nurses in a Greek public hospital.

DESIGN AND METHODS

A mixed-methods qualitative data collection design was used with ad hoc nonparticipant observation and post hoc interviews with the staff involved. Insulin management and administration was observed and compared to international guidelines. A sample of 20 nurses from two medical wards was assessed on 100 occasions of insulin administration, and 8 nurses were subsequently interviewed.

RESULTS

Inter-rater agreement was found to be satisfactory (average κ 0.840). In 61% of all instances, nurses washed their hands before administering insulin, and, in 70%, they donned gloves before injections. In 64.5% of all instances, the nurses did not clean the insulin bottle before inserting the needle, and in 42.7% of instances, they did not check for air bubbles in the syringe. In 89.1% of instances, nurses did not check the injection site for appropriateness or other possible complications. However, in 90.9%, they cleaned the skin at the injection site with an alcohol swab. In 70.9% of all instances, the needle was placed vertically to the skin but without a skinfold. In 89.1% of instances, post-injection care was rated as poor.

CONCLUSION

Overall, compliance with international guidelines regarding insulin administration techniques, as observed in these sample wards, is not satisfactory. Nurses in this Greek hospital tend to administer subcutaneous injections in ways not reflected in current research findings, practice guidelines, or evidence-based care recommendations. Evidently, Greek nurses in this sample require updating on current evidence-based practice, clinical guidelines, and protocols of care regarding routine insulin administration.

Indian Injection Technique Study: Injecting Complications, Education, and the Health Care Professional

INTRODUCTION

Using the Indian and rest of world (ROW) injection technique questionnaire (ITQ) data, we address key insulin injection complications.

METHODS

In 2015 we conducted an ITQ survey throughout India involving 1011 patients. Indian values were compared with those from 41 other countries participating in the ITQ, known here as ROW.

RESULTS

More than a quarter of Indian insulin users described lesions consistent with lipohypertrophy (LH) at their injection sites and approximately 1 in 5 were found to have LH by the examining nurse (using visual inspection and palpation). Just over half of Indian injectors report having pain on injection. Of these, 4 out of 5 report having painful injections only several times a month or year (i.e., not with every injection). Doctors and diabetes educators in India (as opposed to nurses) have a larger role in teaching patients how to inject than they do in ROW. Despite this specialized approach, a very high percentage of patients report that they have not been trained (at least cannot remember being trained) in a wide range of essential injection topics. Only about 30% of Indian injectors get their sites checked at least annually, with nearly a third only having sites checked when they specifically complained and nearly 4 out of 10 never having had their sites checked.

CONCLUSION

Indian HCPs can clearly do a better job covering all the vital topics essential to proper injection habits.

Comment on the New Indian Injection Technique Recommendations: Critical Appraisal of the Real-World Implementation of the Current Guidelines

With an eye on the sequence of two Indian papers concurrently published in Diabetes Therapy, this paper analyzes skin differences among races and points to a lack of organized structured education sessions as the main cause of the high prevalence of lipodystrophy (LD) and consequent poor metabolic control. Only half of all insulin-treated patients reach their therapeutic targets worldwide. The factors involved in this are manifold, including the choice of overlong and repeatedly reused needles, as well as a failure to systematically rotate injection sites, all of which lead to skin LD. Regularly issued guidelines and expert recommendations provide suggestions about how to correct poor injection techniques, but LD still occurs at a high rate and is associated with poor metabolic control, a high risk of complications, frequent severe hypoglycemic episodes, and huge health and social costs. Poor knowledge of subcutaneous tissue anatomy and the physiological response to insulin injection by both health care personnel and patients may contribute to this problem. Moreover, differences in body structure among the races present in our multiethnic societies must be taken into account when choosing needle length and shooting technique in order to avoid accidental intramuscular injections.

Indian Injection Technique Study: Population Characteristics and Injection Practices

INTRODUCTION

It was estimated that 3.2 million Indians with diabetes injected insulin in 2010, but little is known about the techniques used.

METHODS

In 2015 we conducted an injection technique questionnaire (ITQ) survey throughout India involving 1011 patients. Indian values were compared with those from 41 other countries participating in the ITQ, known here as rest of world (ROW).

RESULTS

Mean HbA1c was 8.6. BMI values in India were 1.5-3 units lower than in ROW depending on patient group, meaning the risk of intramuscular (IM) injections is high in India. The mean total daily dose (TDD) of insulin was lower in every category of Indian patient than in ROW, perhaps reflecting the lower BMI. Needle reuse, whether with pens or syringes, is much higher in India than ROW and so is the number of times the needle is used. The majority (56.8%) of Indian insulin users performed only 2 injections/day as opposed to ROW where 45% of patients performed at least 4 injections/day. Indian patients inject insulin in the thighs more often than patients in ROW, a site where IM injections are more risky. Many patients do not have proper access to sharps containers or have other risk factors that could lead to blood-borne pathogen spread. More than 60% of used sharps in India go into the rubbish, with nearly 12% not even having the minimum protection of a cap.

DISCUSSION

The shortest needles are very common in India; however, the level of needle reuse is high. Multiple daily injections therapy is not as common in India as ROW. More focus needs to be given to dwell times under the skin, reconstitution of cloudy insulins, skinfolds, and safe sharps disposal.

New Insulin Delivery Recommendations

Many primary care professionals manage injection or infusion therapies in patients with diabetes. Few published guidelines have been available to help such professionals and their patients manage these therapies. Herein, we present new, practical, and comprehensive recommendations for diabetes injections and infusions. These recommendations were informed by a large international survey of current practice and were written and vetted by 183 diabetes experts from 54 countries at the Forum for Injection Technique and Therapy: Expert Recommendations (FITTER) workshop held in Rome, Italy, in 2015. Recommendations are organized around the themes of anatomy, physiology, pathology, psychology, and technology. Key among the recommendations are that the shortest needles (currently the 4-mm pen and 6-mm syringe needles) are safe, effective, and less painful and should be the first-line choice in all patient categories; intramuscular injections should be avoided, especially with long-acting insulins, because severe hypoglycemia may result; lipohypertrophy is a frequent complication of therapy that distorts insulin absorption, and, therefore, injections and infusions should not be given into these lesions and correct site rotation will help prevent them; effective long-term therapy with insulin is critically dependent on addressing psychological hurdles upstream, even before insulin has been started; inappropriate disposal of used sharps poses a risk of infection with blood-borne pathogens; and mitigation is possible with proper training, effective disposal strategies, and the use of safety devices. Adherence to these new recommendations should lead to more effective therapies, improved outcomes, and lower costs for patients with diabetes.

Injection Technique and Pen Needle Design Affect Leakage From Skin After Subcutaneous Injections

BACKGROUND

After a subcutaneous injection fluid might leak out of the skin, commonly referred to as leakage or backflow. The objective was to examine the influence of needle design and injection technique on leakage after injections in the subcutaneous tissue of humans and pigs.

METHOD

Leakage data were obtained from a post hoc analysis of clinical trial data and from a pig study. Data from the clinical study were used to determine leakage as a function of injection volume, speed and region. Data from the pig study were used to determine leakage as a function of needle wall thickness, needle taper, injection angle, and wait time from end of injection to withdrawal of needle from skin.

RESULTS

Leakage volume was positively related to injection volume. Injections in the abdomen caused less leakage than thigh injections. A 32G needle caused less leakage than a 31G and a 32G tip (tapered) needle, and a "straight in" 90° needle insertion angle caused less leakage than an angled (~45°) insertion. Wait times of minimum 3 seconds caused less leakage than immediate withdrawal of the needle after injection. Needle wall thickness and injection speed did not influence leakage.

CONCLUSIONS

Leakage will be minimized using a thin needle, using 90° needle insertion in the abdomen, injecting maximum 800 µL at a time, and waiting at least 3 seconds after the injection until the needle is withdrawn from the skin.

Can the upper inner side of the thigh become a new option for insulin injection?

OBJECTIVE

Sites for subcutaneous insulin injections include the upper arms, abdomen, buttocks and outer sides of the thigh. No similar study has explored the feasibility of using the inner side of the thigh for insulin injection, since the 4 mm pen needles were introduced for clinical use. This study aimed to determine whether the inner side of the thigh is suitable for insulin injection.

RESEARCH DESIGN AND METHODS

Seventy-five patients with diabetes under insulin therapy from the Inpatient Department of Endocrinology were recruited for this non-blinded, non-randomized observational study. Subcutaneous adipose layer thicknesses of the upper, middle and lower area of the inner and outer thighs of 35 patients were measured by ultrasound, distance from the skin surface to the femoral deep vessels in 20 patients was measured, and insulin was injected at the upper inner and outer sides of the thigh in 20 patients. Pain perception, bleeding or bruising, leakage at the injection sites, blood glucose changes after insulin injection, and preferred ratings of the patients were measured.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02307968.

RESULTS

Subcutaneous adipose layer thicknesses at both the upper inner and outer thighs were more than 4 mm and the minimum distance was 10 mm. Among the 100 injections at the upper inner thigh, only three incidents of perceived pain occurred. No bleeding or bruising and leakage were observed from the inner or outer sides. Furthermore, the difference in blood glucose control between insulin injections at the inner side and outer sides was not statistically significant. Patient ratings for injections at the inner side were similar to injections at the outer side. The key limitation of this study was the small sample size of adult patients as well as the non-randomized controlled design of this study.

CONCLUSION

The upper inner thigh might be a new option for insulin injection rotation.

Nontraditional Considerations With Insulin Needle Length Selection

Ensuring the correct delivery of insulin is essential in the treatment of diabetes. Both proper injection technique and needle length are important considerations for adequate insulin delivery. There have been several studies demonstrating that BMI does not affect efficacy or insulin leakage with shorter pen needles (e.g., 4 or 5 mm vs. 12.7 mm). Additionally, the International Scientific Advisory Board for the Third Injection Technique Workshop released recommendations in 2010 on best practices for injection technique for patients with diabetes, which, with regard to needle length, concluded that 4-mm pen needles were efficacious in all patients regardless of BMI. However, regardless of patients' BMI, insulin injection technique should always be assessed and physically disabling comorbid conditions taken into consideration when choosing a needle length that will be manageable for patients. The purpose of this article is to raise awareness of unique patient circumstances that may warrant the use of the longer 12.7-mm needle.

Spatial distribution of soluble insulin in pig subcutaneous tissue: Effect of needle length, injection speed and injected volume

The spatial distribution of a soluble insulin formulation was visualized and quantified in 3-dimensions using X-ray computed tomography. The drug distribution was visualized for ex vivo injections in pig subcutaneous tissue. Pig subcutaneous tissue has very distinct layers, which could be separated in the tomographic reconstructions and the amount of drug in each tissue class was quantified. With a scan time of about 45min per sample, and a robust segmentation it was possible to analyze differences in the spatial drug distribution between several similar injections. It was studied how the drug distribution was effected by needle length, injection speed and injected volume. For an injected volume of 0.1ml and injection depth of 8mm about 50% of the injections were partly intramuscular. Using a 5mm needle resulted in purely subcutaneous injections with minor differences in the spatial drug distribution between injections. Increasing the injected volume from 0.1ml to 1ml did not increase the intramuscular volume fraction, but gave a significantly higher volume fraction placed in the fascia separating the deep and superficial subcutaneous fat layers. Varying the injection speed from 25l/s up to 300l/s gave no changes in the drug concentration distribution. The method presented gives novel insight into subcutaneous injections of soluble insulin drugs and can be used to optimize the injection technique for subcutaneous drug administration in preclinical studies of rodents.

Safety and efficacy of insulin therapy delivered via a 4mm pen needle in obese patients with diabetes

OBJECTIVE

To determine whether insulin delivered via a 4-mm × 32-gauge pen needle (PN) provides equivalent glycemic control as 8-mm × 31-gauge and 12.7-mm × 29-gauge PNs in obese (body mass index ≥30) patients with diabetes.

PATIENTS AND METHODS

This prospective, multicenter, randomized, open-label, 2-period, crossover, equivalence, home-based study was conducted from October 26, 2010, through May 31, 2012. After a 3-week wash-in period, eligible patients aged 18 to 80 years with a hemoglobin A1c (HbA1c) level of 5.5% to 9.5% (37-80 mmol/mol) were randomized to compare either 4- vs 8-mm PNs or 4- vs 12.7-mm PNs, using each of the 2 assigned PNs for 12 weeks in random order. The primary outcome was change in HbA1c level, with equivalence limits of ±0.4%.

RESULTS

The 274 patients randomized (mean ± SD age, 56.7±11.0 years) had a mean ± SD body mass index of 37.0±6.1 (range, 29.1-59.9) and took up to 350 U of insulin daily; 226 patients were included in the modified intention-to-treat analysis. Mean (95% CI) changes in HbA1c levels with the 4-mm PN were -0.08% (-0.21 to 0.06) and -0.10% (-0.19 to 0.00) vs the 8- and 12.7-mm PNs, respectively, within equivalence margins. The 4-mm PN was less painful than the larger PNs (P<.05), with similar leakage rates reported (4.1%-4.3%). Patients preferred the 4-mm PN over the 12.7-mm PN (P<.05) but not significantly vs the 8-mm PN. There were no differences between PNs in insulin doses and hypoglycemic or hyperglycemic adverse event rates.

CONCLUSION

The 4-mm × 32-gauge PN provides equivalent glycemic control as 8- and 12.7-mm PNs in obese patients with diabetes, with less pain and no increase in leakage. Shorter PNs should be considered in all insulin-requiring patients with diabetes, including those who are obese.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01231984.

Recognition of and steps to mitigate anxiety and fear of pain in injectable diabetes treatment

Injectable treatments, such as glucagon-like peptide-1 receptor agonists and insulin, are options for the pharmacologic treatment of type 2 diabetes. Numerous barriers lead to delay in initiating injectable treatment, which, in turn, may lead to inadequate glycemic control and increased risk of diabetes-related complications, underscoring the need to understand and address these barriers. Barriers to the initiation of injectable therapy, strategies to mitigate barriers, and information about needle attributes and their relation to needle pain are reviewed on the basis of published literature retrieval and our clinical experience. Barriers to the initiation of injectable therapy originate from both patients and practitioners. Anxiety about and fear of injection-associated pain has been estimated to affect approximately 30%-50% of patients before the initiation of diabetes education interventions. Advances in needle design have minimized the pain associated with injections, and recent data suggest that actual pain and bleeding associated with various needle gauges (21-gauge to 31-gauge) are mild. Other barriers include concerns about the ability to handle injectable therapy, concerns about treatment side effects, and impacts on quality of life. Practitioners can help to mitigate barriers to injectable treatment for type 2 diabetes by understanding patient perceptions, improving education, and setting realistic expectations about therapy. Strategies for minimizing injection-associated fear and anxiety include a combination of assessment, appropriate needle selection, patient education, behavioral interventions, and monitoring.

Optimizing insulin injection technique and its effect on blood glucose control

PURPOSE

The purpose of the study is to assess whether proper Injection Technique (IT) is associated with improved glucose control over a three month period.

METHODS

Patients (N = 346) with diabetes from 18 ambulatory centers throughout northern Italy who had been injecting insulin ≥ four years answered a questionnaire about their IT. The nurse then examined the patient's injection sites for the presence of lipohypertrophy (LH), followed by an individualized training session in which sub-optimal IT practices highlighted in the questionnaire were addressed. All patients were taught to rotate sites correctly to avoid LH and were begun on 4 mm pen needles to avoid intramuscular (IM) injections. They were instructed not to reuse needles.

RESULTS

Nearly 49% of patients were found to have LH at study entry. After three months, patients had mean reductions in HbA1c of 0.58% (0.50%-0.66%, 95% CI), in fasting blood glucose of 14 mg/dL (10.2-17.8 mg/dL, 95% CI) and in total daily insulin dose of 2.0 IU (1.4-2.5 IU, 95% CI) all with p < 0.05. Follow-up questionnaires showed significant numbers of patients recognized the importance of IT and were performing their injections more correctly. The majority found the 4 mm needle convenient and comfortable.

CONCLUSIONS

Targeted individualized training in IT, including the switch to a 4 mm needle, is associated with improved glucose control, greater satisfaction with therapy, better and simpler injection practices and possibly lower consumption of insulin after only a three month period.

Intramuscular risk at insulin injection sites--measurement of the distance from skin to muscle and rationale for shorter-length needles for subcutaneous insulin therapy

BACKGROUND

Intramuscular (IM) injection can increase insulin absorption, causing hypoglycemia. Available needle lengths today are 4-12.7 mm for pens and 6-12.7 mm for syringes. We describe the distance (D) from skin surface to muscle fascia at injection sites for subcutaneous (SC) insulin therapy and recommend needle lengths to reduce IM injection risk.

MATERIALS AND METHODS

At two locations in the United States, skin and SC fat thicknesses were measured by ultrasound at the abdomen, arm, thigh, and buttock in diverse adults (body mass index [BMI] range, approximately 19-65 kg/m²) with diabetes (n=341 with one or more paired skin and SC measurement, permitting calculation of D). The natural log of D by body site, BMI, and gender were analyzed using a mixed model to estimate IM risk.

RESULTS

D varied significantly by body site, BMI, and gender (each P<0.001), increasing with higher BMI and in women. Median D ranged from 10.9 mm (95% confidence interval, 10.3, 11.6) at the thigh to 16.9 mm (15.9, 18.1) at the buttock. Minimum D was <3 mm at the thigh and <5 mm elsewhere. When inserted 90° without pinch-up, the most commonly used needle worldwide (8 mm) has estimated IM risks of 25% and 9.7%, respectively, in the thigh and abdomen, versus 1.6% and 0.1%, respectively, with a 4 mm needle. A 45° insertion reduces, but does not eliminate, IM risk with longer needles.

CONCLUSIONS

Gender, BMI, and body site affect D; when combined with needle length and insertion angle, these factors permit detailed estimates of IM insulin injection risk. Such risk varies across sites, appears greatest at the thigh, is unnecessarily increased with 8 mm and 12.7 mm needles, and is greatly reduced with shorter-length needles and good injection technique.

Continuous subcutaneous insulin infusion in preschool children: butt or tummy, which is the best infusion set site?

BACKGROUND

Choosing the right infusion set site can be an important factor in obtaining good glycemic control, especially in very young children. In an attempt to identify the best infusion site, we performed a crossover study in six preschool children with type 1 diabetes using insulin pump therapy.

SUBJECTS AND METHODS

We enrolled six patients 5.2±0.7 years old (range, 4-6 years), with type 1 diabetes for more than 1.5 years, using insulin pump therapy for at least 6 months. For each patient, body mass index, glycated hemoglobin, and all data downloaded from the system were evaluated on two occasions: the first with the infusion set placed on the buttock and the second on the abdomen, each for 3 days. The order of infusion set placement was randomized. Mean capillary blood glucose, mean continuous glycemia, mean area under the curve (AUC) using the trapezoidal rule for both >140 mg/dL and <70 mg/dL, insulin daily dose, carbohydrate/insulin ratio, total basal insulin, total bolus insulin, and mean amplitude of glucose excursions (MAGE) were evaluated.

RESULTS

Mean glycemic values, mean AUC >140 mg/dL, and MAGE were significantly lower when the infusion set was placed on the buttock versus the abdomen (144.6±31.9 mg/dL vs. 166.0±34.8 mg/dL [P=0.000], 28.4±18.3% vs. 48.8±28.2% [P=0.000], and 32±10 vs. 60±15 mg/dL [P<0.001], respectively), whereas mean AUC <70 mg/dL was higher (1.47±2.77% vs. 0.87±1.03% [P<0.001]).

CONCLUSIONS

The present findings suggest that preschool children with type 1 diabetes using insulin pump therapy could benefit from inserting the infusion set in the buttock instead of the abdomen.

Insulin pen injection technique survey in patients with type 2 diabetes in mainland China in 2010

OBJECTIVE

The efficacy of injection therapy in diabetes depends on correct injection technique. To provide patients with guidance in this area and help patients inject themselves correctly, we must understand how they currently inject; therefore, the purpose of this study was to assess the current situation of insulin injection technique in patients with diabetes in mainland China.

DESIGN AND METHODS

From October 2010 to November 2010, a cross-sectional survey of 380 diabetes patients from 20 centers in mainland China was conducted regarding their daily insulin pen injection practice.

RESULTS

Overall, 35.26% of patients had lipohypertrophy; 58.68% of patients had bleeding and bruising, and abdominal lipohypertrophy at injection sites. Bleeding and bruising were more frequent. We found a significant relationship between the frequency of a single needle reuse and lipohypertrophy (r = 0.426, P = 0.000). In addition, there was a significant relationship between the frequency of daily insulin injection and lipohypertrophy (r = 0.146, P = 0.004), between rolling the pen while pulling out the needle after injection and lipohypertrophy (χ(2 )= 7.355, P = 0.007). Bleeding and bruising at injection sites were found to be related to HbA1c levels (r = 0.151, P = 0.003).

LIMITATIONS

A few limitations linked with this survey should be noted. Because of the limited budget, the ultrasound was not used to evaluate lipodystrophy and the photographs of lipodystrophy were not taken. On the other hand, specific size of lipodystrophy and the cost of insulin wastage were not evaluated. Furthermore, the population of this survey is limited, and it was only done in general hospitals and not in community hospitals, therefore, a larger study sample is advisable.

CONCLUSIONS

The insulin injection skill of patients with diabetes in mainland China was poor, and the incidence of lipohypertrophy, bleeding, and needle reuse was high. Frequency of daily insulin injection and needle reuse may relate to the incidence of lipohypertrophy and bleeding. The bleeding and bruising at the injection sites may be associated with suboptimal absorption of injected insulin. Improved education in optimal insulin injection technique, including reducing needle reuse and correct rotation of injection sites should be emphasized.

Effects of age, gender, BMI, and anatomical site on skin thickness in children and adults with diabetes

Objective

We aimed to assess the effects of age, sex, body mass index (BMI), and anatomical site on skin thickness in children and adults with diabetes.

Methods

We studied 103 otherwise healthy children and adolescents with type 1 diabetes aged 5–19 years, and 140 adults with type 1 and type 2 diabetes aged 20–85 years. The thicknesses of both the dermis and subcutis were assessed using ultrasound with a linear array transducer, on abdominal and thigh skin.

Results

There was an age-related thickening of both dermis (p<0.0001) and subcutis (p = 0.013) in children and adolescents. Girls displayed a substantial pubertal increase in subcutis of the thigh (+54%; p = 0.048) and abdomen (+68%; p = 0.009). Adults showed an age-related decrease in dermal (p = 0.021) and subcutis (p = 0.009) thicknesses. Pubertal girls had a thicker subcutis than pubertal boys in both thigh (16.7 vs 7.5 mm; p<0.0001) and abdomen (16.7 vs 8.8 mm; p<0.0001). Men had greater thigh dermal thickness than women (1.89 vs 1.65 mm; p = 0.003), while the subcutis was thicker in women in thigh (21.3 vs 17.9 mm; p = 0.012) and abdomen (17.7 vs 9.8 mm; p<0.0001). In boys, men, and women, both dermis and subcutis were thicker on the abdomen compared to thigh; in girls this was only so for dermal thickness. In both children and adults, the skin (dermis and subcutis) became steadily thicker with increasing BMI (p<0.0001).

Conclusions

Skin thickness is affected by age, pubertal status, gender, BMI, and anatomical site. Such differences may be important when considering appropriate sites for dermal/subcutaneous injections and other transdermal delivery systems.

Ditch the pinch: bilateral exposure injuries during subcutaneous injection

BACKGROUND

Subcutaneous injection into an elevated skin fold poses a risk of "bilateral exposure" injury whereby the needle pierces the opposite side of a skin fold and subsequently enters the tissue of the health care worker (HCW).

METHODS

Retrospective review was conducted examining the Exposure Prevention Information Network (EPINet) needlestick surveillance data. Data from 2,402 injuries occurring during subcutaneous injection were included for analysis. Descriptive data, statistical comparisons, and a logistic regression model reporting relative risk are provided.

RESULTS

Eighty-five bilateral exposure injuries were identified between 2000 and 2009, representing 3.5% (n/N=85/2,402) of all injection-related percutaneous injuries. 65.4% Of the variance in bilateral exposure injury occurrence is explained through examination of the following: (1) manual elevation ("pinching") subcutaneous tissue prior to injection; (2) thin/emaciated patient; (3) injection of insulin; (4) injection of heparin; (5) injection of enoxaparin (Lovenox); (6) if a safety device was used; and (7) whether the health care worker was wearing gloves at the time of the injury (χ(2)7 = 424.2; P<.01).

CONCLUSION

Manual tissue elevation should be avoided to minimize the risk of bilateral exposure injuries.

Identification and comparison of insulin pharmacokinetics injected with a new 4-mm needle vs 6- and 8-mm needles accounting for endogenous insulin and C-peptide secretion kinetics in non-diabetic adult males

Aims/Introduction

Many patients with diabetes now use 5‐, 6‐ or 8‐mm needles for insulin injection. However, it is unclear whether needle length, particularly for shorter needles, affects the pharmacokinetic properties of insulin.

Materials and Methods

This was a three‐way, randomized, cross‐over, single‐center study involving 12 healthy Japanese adult males (age 27.4 ± 4.14 years; weight 64.2 ± 5.2 kg; body fat percentage 18.2 ± 1.5%). Participants received a subcutaneous (abdomen) dose of insulin lispro (1.5 U for participants weighing 55 to <65.0 kg; 2.0 U for participants weighing 65.0 to <80.0 kg) delivered using a 32‐G × 4 mm (32G × 4), 31‐G × 8 mm (31G × 8) or 32‐G × 6 mm (32G × 6) needle with a 3–7‐day washout between doses. Pharmacokinetic parameters of exogenous insulin were identified using non‐linear least squares, where the total insulin concentration was fit to the measured plasma insulin concentration using an overall combined model that accounted for C‐peptide/insulin secretion in addition to the injected dose.

Results

Maximum concentration and area under the curve for 0 to infinity min for insulin were bioequivalent for the 32G × 4 needle relative to the 32G × 6 and the 31G × 8 needles. The time to the maximum insulin concentration was bioequivalent for the 32G × 4 needle relative to the 32G × 6 needle, but not the 31G × 8 needle.

Conclusions

The use of 4‐mm needles is unlikely to change the pharmacokinetic properties of insulin when injected subcutaneously in adults. This trial was registered with UMIN‐CTR (no. UMIN000004469).

Skin and subcutaneous thickness at injecting sites in children with diabetes: ultrasound findings and recommendations for giving injection

BACKGROUND

Children who inject insulin need clear guidelines as to the length of needle best for them. We studied the distance from surface to muscle in children in order to make needle choices which are evidence-based.

METHODS

One hundred one children with type 1 diabetes were divided into three groups according to age: 2-6, 7-13, and 14-17 yr. The thickness of skin and subcutaneous (SC) tissue was measured by ultrasound in all injection sites.

RESULTS

Skin thickness varied from 1.58 mm in the arm of the youngest children to 2.29 mm in the buttocks of the adolescents. Values decreased progressively based on age (2-6 < 7-13 < 14-17) and on body site (arm < thigh < abdomen < buttocks). Skin + SC thickness varied in a similar fashion. The skin surface to muscle distances were <4 mm in nearly 10% of children, especially in the 2-6 yr group. In this group, the rate of intramuscular (IM) injections using the 4-mm pen needle when a pinch-up is not used would be 20.2%. This rate of IM injections doubles when using the 5-mm needle, and when injections are given under similar conditions it triples using the 6-mm needle.

CONCLUSIONS

It seems medically appropriate for all children to use short needles where possible to minimize inadvertent IM injections which may increase glycemic variability. Currently, the safest needle for all children appears to be the 4-mm pen needle. However, when used in children aged 2-6 yr, it should be used with a pinched skin fold.

The role of comfort and discomfort in insulin therapy

Despite the recognized importance of optimal insulin therapy, patient adherence to insulin therapy is an ongoing clinical care challenge. Insulin omission continues to be frequent and underestimated and has been correlated with poorer glycemic control and increased rates of diabetes-related complications. Insulin users consistently identify multiple factors that contribute to insulin injection-related anxiety and to non-adherence. Injection-related discomfort continues to bear a significant contribution. Over the last decade, with advances in needle manufacturing technology, shorter and narrower needles have been associated with progressively improving patient self-rating of injection discomfort. Consequently, patient surveys of insulin users show discomfort to rank in the bottom third of significant contributors by prevalence. However, healthcare providers (HCP) and family member care providers continue to demonstrate a high level of anticipated and perceived pain for the patient. HCP anxiety and pain anticipation are each associated with patient anxiety and may therefore play a significant contributing role in patient non-adherence.

Needle with a novel attachment versus conventional screw-thread needles: a preference and ease-of-use test among children and adolescents with diabetes

BACKGROUND

This usability test investigated the overall preference and usability of the novel NovoTwist® insulin pen needle versus conventional screw-thread needles, when used with Next Generation FlexPen®, in children and adolescents with diabetes.

METHODS

This was an open-label, randomized, crossover usability test in children and adolescents with type 1 diabetes who administered insulin with an insulin pen. Test needles were NovoTwist and the participant's current screw-thread needle (or NovoFine® needle). Following instruction, participants attached the needle to Next Generation FlexPen, made an injection into a foam cushion, and detached the needle. This procedure was conducted three times with both needles in a random order. Responses to 13 questions on user experience with each needle (including overall preference, ease of attachment/detachment of needle/cap, handling, learning, confidence in attachment, and convenience of use) were subsequently recorded on a six-point rating scale (1 = very difficult; 6 = very easy).

RESULTS

Fifteen children aged ≥ 6 to ≤ 12 years and 15 adolescents aged ≥ 13 to ≤ 17 years participated in the test. A significantly higher proportion of children and adolescents (77%) indicated that they would prefer to use NovoTwist compared with screw-thread needles (p = .005). NovoTwist was preferred by most children and adolescents for overall ease of use (77%; p = .005), for ease of attachment (87%; p < .001) and detachment (83%; p < .001), and as the most appropriate needle to handle for daily injections (73%; p = .016). The mean rating for confidence in correct needle attachment was not significantly different between the two needle types. Seven out of eight parents of children who required assistance for their daily insulin injections stated that they would be "very likely" to allow their child to attach NovoTwist.

CONCLUSIONS

These factors may promote confidence in this needle, and thus in self-injecting, among younger patients and their parents.

Insulin administration: selecting the appropriate needle and individualizing the injection technique

INTRODUCTION

Patients with diabetes who receive insulin therapy often fail to meet their targets for metabolic control with insulin injections. Their inadequate glycemic control may be related to incorrect injection procedure.

AREAS COVERED

This review examines the latest data related to insulin injection and needle characteristics, which play an integral role in patient satisfaction. Searches of Medline and Cumulative Index to Nursing and Allied Health Literature databases were conducted. Results show that optimal insulin injection can facilitate glycemic control in pediatric and adult patients. In general, needles shorter than 8 mm are appropriate for normal weight, obese pediatric and adult patients. However, body mass index, gender, race, age and injection site can influence the depth of subcutaneous tissue and thus, the desired needle size and injection technique. Although the abdomen, thighs and buttocks are all recommended injection sites, abdominal injections disperse insulin slightly more rapidly than thigh injections.

EXPERT OPINION

Wider acceptance of needles shorter than 6 mm will occur with more evidence of their safety and efficacy, particularly in children. Development of shorter and thinner needles to make injections even easier and less burdensome may be expected in the future.

Needle with a novel attachment versus conventional screw-thread needles: a preference and usability test among adults with diabetes and impaired manual dexterity

BACKGROUND

NovoTwist(®) (Novo Nordisk A/S, Bagsværd, Denmark) is an insulin pen needle that features a novel attachment and detachment system. The aim of this test was to assess overall preference and handling of NovoTwist compared with conventional screw-thread needles in people with type 1 or type 2 diabetes.

METHODS

One hundred twenty adults with type 1 or type 2 diabetes and manual dexterity dysfunction who were currently self-injecting with an insulin pen were included in this open-label, randomized, crossover test. Participants were stratified according to the impact that manual dexterity problems had on their ability to inject insulin (1 = no effect at all; 4 = a lot), and those rated as 1 were excluded from subanalyses because of low numbers. Following instruction, participants attached the needle to Next Generation FlexPen(®) (Novo Nordisk A/S), made an injection into a foam cushion, and detached the needle; this process was repeated three times with NovoTwist and the participant's current screw-thread needle (or NovoFine(®) [Novo Nordisk A/S]) in a random order. Responses to questions on user experience with each needle were subsequently recorded on a 6-point rating scale (1 = very difficult; 6 = very easy).

RESULTS

Significantly more respondents had a preference for NovoTwist (79%) compared with the conventional screw-thread needles (21%, P < 0.001). Significantly more respondents preferred NovoTwist for both ease of attachment (80%, P < 0.001) and ease of detachment (74%, P < 0.001). Most respondents found NovoTwist the most appropriate needle for performing everyday injections (71%, P < 0.001).

CONCLUSIONS

Such preference by patients has a positive impact on the treatment of diabetes as NovoTwist may alleviate the burden of performing everyday injections through its ease of use.

Compatibility testing of two types of pen needles with a range of injection pens for diabetes medication

Compatibility of two types of needles with a variety of durable and prefilled injection pens for diabetes medication was tested by attaching the needles according to ISO 11608-2 and verifying penetration into the cartridge using air shots and two-dimensional X-rays. NovoFine* and NovoFine Autocover† attached correctly to 20 and 19 out of 21 pen types, respectively. Neither needle type attached to Diapen 3.1/3.2, while NovoFine Autocover attached to most, but not all of OptiSet pens.