Many people who inject or infuse insulin have lipohypertrophy
- Blanco et Al 20131 showed that 64.4% (nearly 2/3) of patients have lipohypertrophy. 76.3% of Patients with Type 1 and 56.1% of patients with Type 2 have lipohypertrophy.
- There was a strong relationship between presence of lipohypertrophy and non-rotation of sites. Correct rotation had the strongest protective value against development of
- Patients who rotated correctly only 5% had lipohypertrophy.
- Patients who either did not rotate or rotated incorrectly 98% had lipohypertrophy.
- Grassi et Al 20142 found that 49.1% of patients had lipohyperthrophy
- In the FITTER ITQ (Injection Technique Questionnaire)3 nurses found lipohypertrophy in 30.8% of patients
- Lipohypertrophy prevalence studies in CSII (continuous subcutaneous insulin infusion) patients showed 42% of patients had lipohypertrophy5. Lipohypertrophy was present in 26.1% of patients, occuring more often in those with a long duration of CSII
Lipohypertrophy leads to unexplained hypoglycaemia and glycaemic variation
- 39.1% of patients with lipohypertrophy have unexplained hypoglycaemia, compared to 5.9% patients without lipohypertrophy*
- 49.1% of patients with lipohypertrophy have glycaemic variation, compared to only 6.5% of patients without lipohypertrophy**
Impact of unexplained hypo and glycaemic variation
- Sub-optimal HbA1c
- Grassi et al 20142 showed a reduction in HbA1c of 0.58% as a result of correct injection technique intervention and avoiding injections into lipohypertrophy.
- Ambulance call outs
- Farmer et Al 20125 :
“The estimated total cost of initial ambulance attendance and treatment at scene was £553,000; if transport to hospital was necessary, the additional ambulance costs were £223,000 plus emergency department costs of £140,000; and the cost of primary care follow-up was estimated as £61,000. The average cost per emergency call was £263. The estimated annual cost of emergency calls for severe hypoglycaemia is £13.6m for England”.
- Unplanned hospital admissions.
- Hammer et al 20096:
“Hospital treatment was a major cost in all countries. In Germany and Spain, costs per SHE (Severe Hypoglaemic Events)for type 1 patients differed from those for type 2 patients in each group. Average SHE treatment costs were higher for patients with type 2 diabetes (Germany, €533; Spain, €691; UK, €537) than type 1 diabetes patients (€441, €577 and €236, respectively). Telephone calls, visits to doctors, blood glucose monitoring and patient education contributed substantially to costs for non-hospitalised patients. Hammer et al concluded that treatment of SHEs adds significantly to healthcare costs. Average costs were lower for type 1 than for insulin-treated type 2 diabetes, in all three countries”.
- Significant costs
- Blanco et al 20131 identified a corrolation between the total daily dose of insulin and the presence of lipohypertrophy. Total daily dose of insulin for patients with lipohypertrophy – averaged 56 units per day. Total daily dose of insulin for patients without lipohypertrophy averaged – averaged 41 units per day. The difference of 15 units equates to annual cost to Spanish Healthcare System of Euro 122 million per year.
- All patients using insulin should be screened for lipohypertrophy.
- The international FITTER recommendations3 states that physical exams for diagnosing lipohypertrophy should be performed on all persons injecting insulin at intervals of at least one year. For those found to have lipohypertrophic lesions the exam should be performed more frequently.
- Prevention and management of lipohypertrophy must be implemented.
- Correct rotation technique has the strongest protected value against lipohypertrophy formation and needle re-use should be avoided.1, 2
- Lipohypertrophy prevention and management is ongoing.
- Use multiple healthy sites and the largest possible sites avoiding injections into lipohypertrophy lesions and re-using needles.1, 2
- Using large and multiple injection sites may increase the risk of accidental intramuscular injections.
- All patients should use 4mm pen needles to minimize intramuscular risk2, 7, 8.
- Injecting insulin into healthy tissue and avoiding injections into lipohypertrophic lesions may increase discomfort and pain which may prevent adherence9.
- It is believed that injections into lipohypertrophic lesions have little or no sensation as the sensory nerve endings have been damaged due to the frequency of micro-trauma.
- Avoiding injecting into lipohypertrophic lesions and injecting into healthy tissue, whilst optimizing insulin absorption, minimizing unexplained hypoglycaemia and gylcaemic variation may however lead to discomfort and even pain when inserting the needle. This is due to healthy sensory nerve endings transmitting pain sensation to the injector.
- By using 4mm pen needles with advanced technology , it is possible to minimize pain and improve comfort thus supporting the patient to adhere to correct rotation and continue injecting into healthy tissue and avoiding injecting into lipohypertrophy.
Continuous subcutaneous insulin infusion - Improved Insulin Flow
- Infusion site complications
- Conwell4 showed that in patients with Type 1 DM using CSII for more than 6 months had a range of skin complications associated with their therapy. Most common were scars less than 3mm in diameter (94%), erythema not associated with nodules (66%), subcutaneous nodules (62%), and lipohypertrophy (42%).
- Pickup10 in a study looking at infusion set problems found that kinking (64%) and blockage (in 54.3%) was associated with more than 3 days use of infusion sets. The most common infusion site problems was lipohypertrophy (26.1%), occurring more often in those with long duration of CSII (P=0.01).
- Optimal frequency for changing catheters
- Schmid11 studied patients using CSII and showed that infusion set and injection site problems occurred in measurable frequencies at about the third day of catheter use. Local complications increased over time with 40% of patients reporting significant issues when using a catheter for 5 days. This supports manufacturers’ recommendations that insulin pump catheters should be used for a maximum of 48 to 72 hours in order to avoid adverse events and potential metabollic deterioration.
- Optimal cannula length
- Imaging of CSII set and fluid deposition has been formed in vivo in swine using fluoroscopy of constrast media12. A novel 28 gauge, 6mm, ported polymer catheter with a 30 gauge introducer needle exhibited diffuse subcutaneous patterns – the preferred pattern. Depots showed increased diffusivity (desired pattern) with side-port flow from the new polymer.
- Improved flow CSII
- Natasha13 has shown that novel set polymers show promise in reducing silent occlusion. Reductions of 88 – 95% in mean % time of flow interruptions were demonstrated with new polymers compared to currently available commercial polymers. In a study comparing new polymer with Medtronic Quick-set®14, the former had fewer flow interruptions (silent occlusions), fewer occlusion alarms and less time with interrupted flow15.
Clinician and Patient Safety
- Safety – NSI & AEB (accidental exposure to blood)
- Studies undertaken in the US and Italy show that approximately 1 out of 6 hypodermic syringes and needles are contaminated with blood16. The risk of needlestick injury from blood contaminated hypodermic needles is comparable to the risk of IV catheters17. Studies have shown that sustaining a deep injury carries 3 times the risk of transmitting the risk of HIV or Hepatitis C18,19. Hypodermic needles have the greatest potential for deep injuries. Safety engineered devices when introduced into healthcare settings where a « safety culture » has been fostered and appropriate training given, can signficantly and sustainably decrease the incidence of needlestick injuries20, 21, 22, 23, 24.
- Injection technique implications
- Longer needle length previously recommended for insulin injections in both adults and children have been shown to increase the risk of intramuscular injections (FITTER recos). Intramuscular injection can lead to rapid insulin absorption and its decoupling from the glucose rise. True solutions have been proposed for avoiding intramuscular injections :
- Lifting a skin fold (into which the injection is given)
- And / or the use of shorter needles
- However, when a healthcare worker lifts skin fold their fingers are at risk of « through and through » needlestick injury because of their proximity to the injection site. This risk is higher when longer needles are used.
- Education and training (creating a « safety culture »)
- The introduction to safety devices must coincide with sensitization of healthcare workers to the risk of needlestick injury and the best practices for avoiding them. Procedures and protocols must include correct use of products available to healthcare workers including gloves, sharps containers, gowns etc. Recapping needles must be strictly prohibited. Discarding of sharps swiftly after use into appropriate containers which must not be over-filled. Education and training should be extended to downstream workers or may also be at risk from medical sharps.
- Value and responsibility
- Initial cost of safety injection devices may be higher than convential devices, but significant reductions in needlestick injury and other complications will recover these costs.
- Larmuseau25 has shown that conversion safety saves money. In his study, nearly 0.5 million euros a year was saved.