A 4-mm needle reduces the risk of intramuscular injections without increasing backflow to skin surface in lean diabetic children and adults

Backflow reduction in local injection therapy with gelatin formulations

The local injection of therapeutic drugs, including cells, oncolytic viruses and nucleic acids, into different organs is an administrative route used to achieve high drug exposure at the site of action. However, after local injection, material backflow and side effect reactions can occur. Hence, this study was carried out to investigate the effect of gelatin on backflow reduction in local injection. Gelatin particles (GPs) and hydrolyzed gelatin (HG) were injected into tissue models, including versatile training tissue (VTT), versatile training tissue tumor-in type (VTT-T), and broiler chicken muscles (BCM), using needle gauges between 23 G and 33 G. The backflow material fluid was collected with filter paper, and the backflow fluid rate was determined. The backflow rate was significantly reduced with 35 μm GPs (p value < .0001) at different concentrations up to 5% and with 75 μm GPs (p value < .01) up to 2% in the tissue models. The reduction in backflow with HG of different molecular weights showed that lower-molecular-weight HG required a higher-concentration dose (5% to 30%) and that higher-molecular-weight HG required a lower-concentration dose (7% to 8%). The backflow rate was significantly reduced with the gelatin-based formulation, in regard to the injection volumes, which varied from 10 μL to 100 μL with VTT or VTT-T and from 10 μL to 200 μL with BCM. The 35 μm GPs were injectable with needles of small gauges, which included 33 G, and the 75 μm GPs and HG were injectable with 27 G needles. The backflow rate was dependent on an optimal viscosity of the gelatin solutions. An optimal concentration of GPs or HG can prevent material backflow in local injection, and further studies with active drugs are necessary to investigate the applicability in tumor and organ injections.

Investigation of appropriate needle length considering skin thickness with the real injection posture for insulin injections in diabetic patients

BACKGROUND

Insulin treatment is widely used not only for type 1 but also for type 2 diabetes patients. Insulin must be injected into the subcutaneous tissue to be effective. The needle length has been shortened for safety and efficiency. However, whether patients use an appropriate needle length is unclear.

METHODS

Skin thickness was measured by ultrasound with patients in their usual posture during injection. Furthermore, the effect of the intervention in which the needle length was changed was investigated.

RESULTS

Thirty-eight percent of the patients had fluid leakage and injected the needle intradermally. The average skin thickness was 3.3 mm while sitting, which was greater than that in a previous report including measurements taken while lying down. Consequently, the skin thickness was > 4 mm in 9.5% of the patients who used 4-mm needles. Cases of leakage and intradermal injection decreased when the needle length was changed.

CONCLUSIONS

This study identified that the needle length should be considered in patients with thick skin or a lower body mass index due to possibility of intradermal injection.

Consensus on Choice of Insulin Pen Devices in Routine Clinical Practice in India

Although insulin delivery devices are widely used by the patients, there is a paucity of published guidelines to help professionals manage their patients in insulin therapies. To provide simple and easily implementable guidelines to health care physicians on the choice of insulin delivery devices in routine clinical practice, experts in diabetes gathered together and discussed the recommendations at the National insulin Summit 2018. An ideal insulin delivery device should accurately deliver the prescribed dose of insulin and be easy to use. Recommendations are: (1) insulin should be initiated by using an insulin device if the patient seems to discontinue insulin therapy. (2) Pen devices offer accurate dosing than a syringe and vial and are associated with cost savings in the long term. (3) Switching over from syringes and vial to disposable pen devices improves adherence. (4) FlexPen^® offers better accuracy, and it requires lower dose force and injection force than SoloStar^® and KwikPen^® (5). Durable delivery pens such as NovoPen^® 4 maintain accuracy and low dose force compared with vials and syringes. (6) One pen should be used by only one patient. (7) Regular counseling on the proper use of the pen device is required regularly. This consensus-based recommendation is a useful reference tool for health care practitioners to initiate insulin therapy in patients with diabetes by using the appropriate insulin pen device.

The Injection Technique Factor: What You Don't Know or Teach Can Make a Difference

IN BRIEF To be consistently effective, insulin must be delivered into subcutaneous tissue. If insulin is delivered intramuscularly, its uptake and action become variably faster, leading to suboptimal, inconsistent glucose control. The best strategy to avoid intramuscular injection is to use the shortest needles available. Injection sites should be rotated systematically to prevent lipohypertrophy, which also substantially affects insulin uptake and action. New evidence-based insulin delivery recommendations are available, and awareness of them should lead to more effective use of insulin therapy, improved clinical outcomes, and considerable cost savings.

Evaluating the Impact of Human Factors and Pen Needle Design on Insulin Pen Injection

BACKGROUND

Limited published data exists quantifying the influence of human factors (HF) and pen needle (PN) design on delivery outcomes of pen injection systems. This preclinical in vivo study examines the impact of PN hub design and applied force against the skin during injection on needle penetration depth (NPD).

METHOD

To precisely locate injection depth, PN injections (20 µl; 2 IU, U-100 volume equivalent) of iodinated contrast agent were administered to the flank of Yorkshire swine across a range of clinically relevant application forces against the skin (0.25, 0.75, 1.25, and 2.0 lbf). The NPD, representing in vivo needle tip depth in SC tissue, from four 32 G × 4 mm PN devices (BD Nano^™ 2nd Gen and three commercial posted-hub PN devices; n = 75/device/force, 1200 total) was measured by fluoroscopic imaging of the resulting depot.

RESULTS

The reengineered hub design more closely achieved the 4 mm target NPD with significantly less variability ( P = .006) than commercial posted-hub PN devices across the range of applied injection forces. Calculations of IM (intramuscular) injection risk completed through in silico probability model, using NPD and average human tissue thickness measurements, displayed a commensurate reduction (~2-8x) compared to conventional PN hub designs.

CONCLUSIONS

Quantifiable differences in injection depth were observed between identical labeled length PN devices indicating that hub design features, coupled with aspects of variable injection technique, may influence injection depth accuracy and consistency. The reengineered hub design may reduce the impact of unintended individual technique differences by improving target injection depth consistency and reducing IM injection potential.

EADSG Guidelines: Insulin Storage and Optimisation of Injection Technique in Diabetes Management

To date, insulin therapy remains the cornerstone of diabetes management; but the art of injecting insulin is still poorly understood in many health facilities. To address this gap, the Forum for Injection Technique and Therapy Expert Recommendations (FITTER) published recommendations on injection technique after a workshop held in Rome, Italy in 2015. These recommendations are generally applicable to the majority of patients on insulin therapy, athough they do not explore alternative details that may be suitable for low- and middle-income countries. The East Africa Diabetes Study Group sought to address this gap, and furthermore to seek consensus on some of the contextual issues pertaining to insulin therapy within the East African region, specifically focusing on scarcity of resources and its adverse effect on the quality of care. A meeting of health care professionals, experts in diabetes management and patients using insulin, was convened in Kigali, Rwanda on 11 March 2018, and the following recommendations were made: (1) insulin should be transported safely, without undue shaking and exposure to high (> 32 °C) temperature environments. (2) Insulin should not be transported below 0 °C. (3) If insulin is to be stored at home for over 2 months, it should be stored at the recommended temperature of 2-8 °C. (4) Appropriate instructions should be given to patients while dispensing insulin. (5) Insulin in use should be kept at room temperature and should never be kept immersed under water. Immersing insulin under water after the vial has been pierced carries a high risk of contamination, leading to loss of potency and likelihood of causing injection abscesses. (6) The shortest available needles (4 mm for pen and 6 mm for insulin syringe) should be preferred for all patients. (7) In routine care, intramuscular injections should be avoided, especially with long-acting insulins, as it may result in severe hypoglycaemia. (8) The practice of slanting the needle excessively should be avoided as it results in sub-epidermal injection of insulin which leads to poor absorption and may cause "tattooing" of the skin and scarring. (9) In patients presenting in a wasted state, with "paper-like skin", injections should, if possible, be initiated with pen injection devices, so as to utilise the 4-mm needle without lifting a skin fold (pinching the skin); otherwise lifting of a skin fold is required, if longer needles are utilised. (10) Reuse of needles and syringes is not recommended. However, as the reuse of syringes and needles is practiced for various reasons, and by many patients, individuals should not be given alarming messages; and usage should be limited to discarding when injections become more painful; but at any rate not to exceed reusing a needle more than 5 times.

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.

Turkish Insulin Injection Technique Study: Population Characteristics of Turkish Patients with Diabetes Who Inject Insulin and Details of Their Injection Practices as Assessed by Survey Questionnaire

INTRODUCTION

Over 7 million people in Turkey have diabetes. Of the 1 million who inject insulin little is known of their habits and injection techniques.

METHODS

We conducted an Injection Technique Questionnaire (ITQ) survey throughout Turkey that involved 1376 patients from 56 centers. Turkish values were compared with those from 41 other countries participating in the ITQ, known here as Rest of World (ROW).

RESULTS

The majority (50.4%) of Turkish insulin users give four injections/ day as opposed to ROW, where only 30.9% do. The abdomen is the most common injection site used by Turkish patients, but they also inject insulin in multiple body sites more often than do patients in ROW. Body mass index values in Turkey were 0.75 units higher than those in ROW as was the mean total daily dose (average daily dose [ADD]) of insulin (54.0 IU in Turkey vs. 47.4 IU in ROW). Mean glycated hemoglobin (HbA1c) in Turkey was 9.1%, which is higher than in ROW and possibly related to the higher BMI and ADD. Turkish patients use insulin analogs (short and long-acting) more frequently than do patients in ROW. The shortest pen needles (4 mm) are used by about one-third of patients in Turkey, but the longer ones (8 mm) are equally common. Needles are reused in Turkey at a rate of 3.4 injections/single needle. However, needle reuse, whether with pens or syringes, is lower in Turkey than ROW, as is the number of times a reused needle is used. More than 75% of used sharps in Turkey go into the rubbish, with nearly 6% having no protection of the tip.

CONCLUSION

The continued use of 8-mm needles raises the risk of intramuscular injections in Turkish patients. Despite full reimbursement, needle reuse still remains an important issue. More focus needs to be given to dwell times under the skin, reconstitution of cloudy insulant, correct use of skin folds and safe disposal of sharps.

FUNDING

BD Diabetes Care.

Forum for Injection Technique and Therapy Expert Recommendations, India: The Indian Recommendations for Best Practice in Insulin Injection Technique, 2017

Health-care professionals in India frequently manage injection or infusion therapies in persons with diabetes (PWD). Patients taking insulin should know the importance of proper needle size, correct injection process, complication avoidance, and all other aspects of injection technique from the first visit onward. To assist health-care practitioners in their clinical practice, Forum for Injection Technique and Therapy Expert Recommendations, India, has updated the practical advice and made it more comprehensive evidence-based best practice information. Adherence to these updated recommendations, learning, and translating them into clinical practice should lead to effective therapies, improved outcomes, and lower costs for PWD.

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.

Subcutaneous Administration of Bortezomib: A Pilot Survey of Oncology Nurses

Subcutaneous (SC) administration of the proteasome inhibitor bortezomib was approved in the United States and European Union in 2012. There is limited guidance regarding how to administer SC bortezomib and a general lack of clear direction on optimal techniques for administering SC chemotherapy injections. Nurses may be utilizing different techniques, and inconsistent techniques may result in injection-site reactions, causing patient discomfort and treatment cessatioin. This observational survey of oncology nurses in community oncology clinics aimed to identify techniques being used and explore nurses’ opinions about SC bortezomib administration. A 44-question electronic survey was developed, based on the current literature regarding appropriate techniques for administering SC injections. A total of 43 nurses from 17 clinics in 12 states responded. The majority (74%) had been practicing oncology nursing for at more than 5 years. Respondents predominantly used and preferred the abdomen for injections (88%); 81% used a skin lift to ensure injection into adipose tissue. There was no relationship between the angle of insertion and the needle length; 51% used an air-bubble technique. Nurses took 3–5 (49%), 5–10 (35%), 10–30 (9%), or > 30 (7%) seconds to administer each mL of SC bortezomib injection. All nurses completely/somewhat agreed that practice guidelines would be important for standardizing SC bortezomib administration. Advanced practice registered nurses (APRNs) shared the responsibility for ordering SC bortezomib, according to 53% of respondents. These findings could help APRNs improve the quality of patient care, may help minimize adverse events and maximize effective therapy, and could help inform the development of practice guidelines.

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.

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.

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.

Patients on subcutaneous allergen immunotherapy are at risk of intramuscular injections

Background

Allergen-specific subcutaneous immunotherapy is an effective treatment for certain allergic disorders. Ideally, it should be administered into the subcutaneous space in the mid-posterolateral upper arm. Injections are commonly given using a standard allergy syringe with a needle length of 13 mm. Therefore, there is a risk of intramuscular administration if patients have a skin-to-muscle depth <13 mm, which may increase the risk of anaphylaxis. The objective of this study was to determine whether the needle length of a standard allergy syringe is appropriate for patients receiving subcutaneous immunotherapy.

Methods

Ultrasounds of the left posterolateral arm were performed to measure skin-to-muscle depth in 200 adults receiving subcutaneous immunotherapy. The proportion of patients with a skin-to-muscle depth >13 mm vs. ≤13 mm was assessed and baseline characteristics of the two groups were compared. The proportion of patients with skin-to-muscle depths > 4 mm, 6 mm, 8 mm and 10 mm were also calculated. Multivariable logistic regression was performed to identify predictors of skin-to-muscle depth.

Results

Of the 200 patients included in the study, 80% had a skin-to-muscle depth ≤13 mm; the majority (91%) had a skin-to-muscle depth >4 mm. Body mass index was found to be a significant predictor of skin-to-muscle-depth.

Conclusions

Most patients receiving subcutaneous immunotherapy have a skin-to-muscle depth less than the needle length of a standard allergy syringe (13 mm). These patients are at risk of receiving injections intramuscularly, which may increase the risk of anaphylaxis. Using a syringe with a needle length of 4 mm given at a 45° angle to the skin may decrease this risk.

Comparison of the effects of a new 32-gauge × 4-mm pen needle and a 32-gauge × 6-mm pen needle on glycemic control, safety, and patient ratings in Japanese adults with diabetes

BACKGROUND

This study was designed to evaluate two pen needles (PNs) with the same diameter but different lengths (4 mm and 6 mm) and different needle tip shapes (straight and tapered) to compare their effects on glycemic control, perceived pain, safety, patients' ease of use and preferences, and visual impression.

SUBJECTS AND METHODS

In this prospective, open-label, controlled crossover study, 41 insulin-treated patients with type 1 or type 2 diabetes were randomized into either Group 1 (the 32-gauge × 4-mm PN was used during Study Period 1, then the 32-gauge × 6-mm PN was used during Study Period 2) or Group 2 (the order for using the PNs was reversed).

RESULTS

The 32-gauge × 4-mm PN provided an equivalent glycemic control in diabetes patients as the 32-gauge × 6-mm PN, with an equivalent occurrence rate of adverse events. The 32-gauge × 4-mm PN was perceived as significantly less painful and rated as significantly more favorable than the 32-gauge × 6-mm PN according to the survey results on patients' ease of use and preferences and on their visual impressions.

CONCLUSIONS

The 32-gauge × 4-mm PN was not only as safe and efficacious as the 32-gauge × 6-mm PN, but also was perceived as less painful, easier to use, and more favorable to Japanese adult patients with diabetes.

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.

Translating the research in insulin injection technique: implications for practice

PURPOSE

Glucose variability leading to suboptimal glycemic control is common among people using injection therapies. Advanced technology and new studies have identified important issues related to injection technique: needle length and gauge, body mass index, skin and subcutaneous tissue thickness, adequate resuspension of cloudy insulins, leakage, choice of injection site and rotation, pinching a skinfold, and lipohypertrophy. All these issues can affect pain and bruising, insulin absorption, and blood glucose levels. The purpose of this article is to review current and past research regarding insulin injection therapy and to provide practical, translational information regarding injection technique, teaching/learning techniques specific to insulin administration, and implications for diabetes self-management education and support.

CONCLUSION

International injection recommendations for patients with diabetes have recently been published and have identified specific recommendations for health care professionals. This article provides an evidence-based translational and practical review of the research regarding injection technique and teaching/learning theory. Diabetes educators need to reevaluate how they provide instruction for the administration of insulin and other injectable medications. Research regarding skin and subcutaneous thickness reveals that shorter needles may be appropriate for the majority of patients regardless of body mass index. Periodic reassessment of injection technique, including suspension of cloudy insulins and inspection of injection sites for lipohypertrophy, is a critical aspect of the role of the diabetes educator. An injection checklist is provided as a guide for diabetes educators.

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.

Subcutaneous adipose tissue thickness in adults - correlation with BMI and recommendations for pen needle lengths for subcutaneous self-injection

OBJECTIVE

One of the aims of a subcutaneous (SC) injection is to avoid intradermal or intramuscular injections. Pen systems are an alternative solution to single-use syringes and have become standard for example diabetes therapy. Shorter and smaller needles minimize pain and the risk of intramuscular injections. The thickness of subcutaneous adipose tissue (SCAT) varies with position and with body mass index (BMI). The aim of this study was the creation of a map of SCAT thickness at typical spots for SC self-injection.

MATERIALS AND METHODS

MRI scans of 116 prospectively enroled volunteers (56 men and 60 women) were analysed. SCAT thickness was determined at 17 spots over the abdominal wall, left thigh, buttocks and upper arm, typical sites for subcutaneous self-injection. SCAT thicknesses were correlated with BMI and waist-to-hip ratio (WHR), and a linear curve fit was performed. The best fitting linear functions for the prediction of the SCAT thickness dependent on BMI and WHR were derived.

RESULTS

Correlations between SCAT and BMI were higher (0·67-0·21) than with WHR (-0·67 to 0·09). In women, correlation coefficients between SCAT data at the abdomen and BMI/WHR were higher than in men. On the other hand, data showed better correlations at the extremities in men.

CONCLUSIONS

The data, with correlation between BMI and fat thickness at different injection sites in relation to gender, provide guidance in selecting an adequate pen needle length for deep and safe subcutaneous self-injection. WHR was a much weaker predictor when compared to BMI.

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.

Insulin delivery by injection in children and adolescents with diabetes

Type 1 diabetes is treated with insulin, which has traditionally been delivered by vial and syringe. However, for many patients, dosing inaccuracy, pain, anxiety, inconvenience, and social acceptability present barriers to this method of administration (1-5). This has contributed to the increased popularity of alternative insulin delivery systems, including pen delivery devices (4, 6). Evidence suggests that discreet devices, such as insulin pens, facilitate adherence to intensive insulin therapy regimens, help improve lifestyle flexibility, and reduce injection pain compared with the conventional syringe-based regimens, as shown in studies in adults and adolescents (7). In addition, compared with the vial and syringe method of insulin administration, pens may provide more accurate dosing - which is particularly important in children - thereby improving short-term blood glucose control and potentially improving long-term outcomes (5, 8). Children, in particular, may benefit from insulin pens that are simple to use as adherence issues may be more evident in this patient group (9). Pens for insulin delivery in children with type 1 diabetes have been used for a long time in Europe, and have recently gained in popularity in many other places around the world (4, 10). Furthermore, the conventional vial and syringe method of insulin delivery is beginning to be considered as obsolete (11). Moreover, there is a continued drive to improve insulin pen technology, to refine and enhance the functionality and usability of these pens. However, despite recent advances in pen design and function, the selection of pens available especially for children is limited.

New injection recommendations for patients with diabetes

AIM

Injections administered by patients are one of the mainstays of diabetes management. Proper injection technique is vital to avoiding intramuscular injections, ensuring appropriate delivery to the subcutaneous tissues and avoiding common complications such as lipohypertrophy. Yet few formal guidelines have been published summarizing all that is known about best practice. We propose new injection guidelines which are thoroughly evidence-based, written and vetted by a large group of international injection experts.

METHODS

A systematic literature study was conducted for all peer-reviewed studies and publications which bear on injections in diabetes. An international group of experts met regularly over a two-year period to review this literature and draft the recommendations. These were then presented for review and revision to 127 experts from 27 countries at the TITAN workshop in September, 2009.

RESULTS

Of 292 articles reviewed, 157 were found to meet the criteria of relevance to the recommendations. Each recommendation was graded by the weight it should have in daily practice and by its degree of support in the medical literature. The topics covered include The Role of the Professional, Psychological Challenges, Education, Site Care, Storage, Suspension and Priming, Injecting Process, Proper Use of Pens and Syringes, Insulin analogues, Human and Pre-mixed Insulins, GLP-1 analogs, Needle Length, Skin Folds, Lipohypertrophy, Rotation, Bleeding and Bruising, Pregnancy, Safety and Disposal.

CONCLUSION

These injecting recommendations provide practical guidance and fill an important gap in diabetes management. If followed, they should help ensure comfortable, effective and largely complication-free injections.

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

OBJECTIVE

We aimed to establish the ideal injection techniques using 5-mm needles to reliably inject insulin into the subcutaneous fat in both children and adults and to quantify the associated pain and leakage of the test medium.

RESEARCH DESIGN AND METHODS

A total of 259 subjects (122 children/adolescents and 137 adults) were injected with sterile air corresponding to 20 IU insulin (200 microl) with 32-G 5-mm needles at 90 degrees or 45 degrees , in the abdomen and thigh, and with or without a pinched skin fold. Injection depth was assessed via ultrasonography. Subjects rated pain on a visual analog scale. Test medium injections into the abdomen and thigh (0.2-0.6 ml) were also administered to assess injection leakage.

RESULTS

Among children, 5.5% of injections were intramuscular (IM) and 0.5% were intradermal, while in adults, the incidence was 1.3 and 0.6%, respectively. The frequency of IM injections was greater in boys and negligible among adult women. Subcutaneous fat thickness was the primary predictor of the likelihood of IM injections (P < 0.001). A third of all patients reported experiencing no pain during insulin injection, with children/adolescents experiencing considerably more discomfort than adults. Some leakage of medium was observed, but was unrelated to injection volume and was generally minimal.

CONCLUSIONS

5-mm needles are reliably inserted into subcutaneous fat in both adults and children. These needles were associated with reduced pain and minimal leakage. We recommend an angled injection with a pinched skin fold for children, while in adults, the technique should be left to patient preference.

Insulin leakage value in relation to pen needle length and administered dose after subcutaneous injection

OBJECTIVE

During a subcutaneous injection with commonly used pen needles, the safety of drug administration plays an essential role. Today short needles with a length of 5.0 mm are increasingly being used. However, so far it is unresolved whether short needles of <5.0 mm affect the safety of insulin injections because of an increased backflow to the skin surface. We examined the influence of needle length and administered insulin dosage on the insulin backflow and the distribution of human insulin in the tissue by a quantitative determination of the amount of backflow of insulin to the skin surface. For the first time a new 4.5-mm pen needle was examined for its administration safety.

RESEARCH DESIGN

Human insulin was radioactively marked. By means of an insulin pen different insulin dosages with pen needles of different lengths into fresh pork rind (ex vivo model) were administered. The amount of the marked insulin leaking from the tissues at the injection site was covered and absorbed immediately into a cotton swab. The amount of leakage was calculated by means of the radioactivity taken up by the swab.

RESULTS

The amount of leakage for each measurement was less than 1% of the total dosage administered. The amount of leakage increased with increased dosage administered in absolute terms, but expressed as a percentage of the increased dosage administered the leakage decreased.

CONCLUSION

The needle length (between 12 mm and 4.5 mm) did not have a meaningful influence on the amount of leakage; however, significant differences with different needle lengths could be observed.

Comparative glycemic control, safety and patient ratings for a new 4 mm x 32G insulin pen needle in adults with diabetes

OBJECTIVE

Pen needles (PN) for subcutaneous insulin therapy have become smaller; 5 mm PNs are now the shortest in use. We evaluated the safety, efficacy and patient ratings of a new 4 mm x 32 gauge (G) PN.

RESEARCH DESIGN AND METHODS

Subjects with type 1 and type 2 diabetes and HbA1c 5.5% to 9.5% participated in a randomized non-inferiority cross-over trial, at four U.S. centers. Subjects used 4 mm x 32G PNs and either 5 mm x 31G PNs (4/5 mm) or 8 mm x 31G PNs (4/8 mm) in two, 3-week treatment periods; order of needle use was controlled. Subjects were either 'low dose' or 'regular dose' users (highest single insulin dose <or= 20 units and 21-40 units, respectively). Percent absolute change in serum fructosamine (% |Delta Fru|) was the primary endpoint; unexplained, severe hypo- or hyperglycemia was a secondary measure. Leakage at injection sites and pain measured by visual analog scale were tertiary measures. Equivalent glycemic control was defined á priori as % |Delta Fru| (including 95% CI) within 20%; 40 subjects per subgroup provides 90% power at alpha = 0.05.

CLINICAL TRIAL REGISTRATION

The study was registered on clinicaltrials.gov (identifier: NCT00928057).

RESULTS

Of 173 subjects randomized, 168 completed the study, and 163 were included in the fructosamine analyses--83 and 80 in the 4/5 mm and 4/8 mm groups, respectively. Subjects were 56% male, mean 52.6 yrs, 63% type 2. Baseline HbA1c = 7.5 +/- 1.0% and fructosamine 301 +/- 55.1 micromol/L. Mean % |Delta Fru| was 4.9% (95% CI 3.8, 6.0) and 5.5% (4.5, 6.4), respectively, for the 4/5 mm and 4/8 mm groups, meeting glycemic equivalence criteria; results were similar in both dose groups. The median |Delta Fru| was 11.0 micromol/L (8.0, 13.0) and 13.5 micromol/L (9.8, 18.0) for the 4/5 mm and 4/8 mm groups, respectively. Unexplained, severe hypo- and hyperglycemic episodes were infrequent and not different between PNs. The 4 mm PN was rated significantly less painful and preferred by approximately 2/3 of subjects (p < 0.01). All three PNs had similar reported injection site leakage.

LIMITATIONS

The study was of relatively short duration, in adults in the U.S. Further trials in other patients (e.g., GLP-1 users, pediatrics, obese) should be performed.

CONCLUSIONS

The 4 mm x 32G PN provided equivalent glycemic control compared to 31G, 5 mm and 8 mm PNs with reduced pain, no difference in insulin leakage and was preferred by patients.

Skin and subcutaneous adipose layer thickness in adults with diabetes at sites used for insulin injections: implications for needle length recommendations

OBJECTIVE

During subcutaneous insulin therapy, inadvertent intramuscular (IM) injections may increase pain and/or adversely affect glucose control. The most appropriate needle length for patients depends on skin thickness (ST) and the distance to muscle fascia. ST and subcutaneous adipose layer thickness (SCT) were measured in adults with diabetes.

RESEARCH DESIGN AND METHODS

A total of 388 US adults with diabetes (in three BMI subgroups: <25, 25-29.9, and >or=30 kg/m(2)) with diverse demographic features were evaluated. Each subject had ultrasound measurements of ST and SCT at four injection sites.

RESULTS

Subjects had BMI 19.4-64.5 kg/m(2), age 18-85 years; 40% Caucasian, 25% Asian, 16% Black, 14% Hispanic; 28% type 1 diabetes. Mean ST (+/-95% CI) was: arm 2.2 mm (2.2, 2.3), thigh 1.9 mm (1.8, 1.9), abdomen 2.2 mm (2.1, 2.2) and buttocks 2.4 mm (2.4, 2.5). Multivariate analyses showed body site, gender, BMI, and race are statistically significant factors for ST but effects were small. Thigh ST was <0.6 mm thinner than the buttocks. Differences of 10 kg/m(2) account for 0.2 mm ST variation. Mean SCT was: arm 10.8 mm (10.2, 11.3), thigh 10.4 mm (9.8, 10.9), abdomen 13.9 mm (13.2, 17.7) and buttocks 15.4 mm (14.7, 16.2). Females had 5.1 mm greater SCT. Differences of 10 kg/m(2) account for 4 mm SCT variation.

ADVERSE EVENTS

A few mild hypo- or hyperglycemia events, unrelated to study procedure, were detected and treated before subject discharge from study visits.

LIMITATIONS

Only adults in the US were studied; some measurements could not be obtained on every subject, at every injection site.

CONCLUSIONS

Injection site ST does not differ by clinically significant degrees in demographically diverse adults with diabetes; SCT has a wider range. Needles >or=8 mm, inserted perpendicularly, may frequently enter muscle in limbs of males and those with BMI <25 kg/m(2). With 90 degrees insertion, needles 4-5 mm enter the subcutaneous tissue with minimal risk of IM injection in virtually all adults. These data will assist recommending appropriate length needles for subcutaneous insulin injections in adults.