**12. Needle reuse**

which in one case led to a conclusion that injecting into LH did not worsen inherent variability of insulin uptake [69–72]. A crossover glucose clamp study [73] showed that both insulin absorption and action when injected into LH are blunted and are 3–5X more variable than when the same insulin dose is injected into non-LH areas. A controlled mixed-meal tolerance test in the same study also showed a reduced insulin absorption, and prolonged postprandial hyperglycemia when the insulin was injected into the LH area. When patients change from delivering insulin into LH and move to normal tissue, they are at risk of hypoglycemia and must lower their doses. Gentile [74, 75] has shown convincingly that HCPs trained to detect LH can do so with extremely high efficiency using the physical examination alone, achieving

• Switching injections from lipohypertrophy to normal tissue often requires a decrease in the dose of insulin injected. The amount of change varies from one individual to another and should be guided by frequent blood glucose measurements. Reductions often exceed 20%

• Injections should be systematically rotated in such a way that they are spaced at least 1 cm (or approximate width of an adult finger) from each other in order to avoid repeat tissue

• One scheme with proven effectiveness involves dividing the injection site into quadrants (or halves when using the thighs or the buttocks), using one quadrant per week and mov-

A multicenter interventional study in the UK [78] showed that education focused on these recommendations resulted in significantly reduced clinically detectable LH after 6 months, with LH either disappearing completely or decreasing by approximately 50% from its original size. The mean HbA1c fell by more than 4 mmol/L, and there were significantly reduced levels of unexpected hypoglycemia and glycemic variability. The mean TDD of insulin in the

In a controlled, prospective, multicenter study in French patients [79], all of whom had LH, the intervention consisted of instructions to move injections to non-LH areas, to correctly rotate within injection sites, to forego needle reuse, and to switch to 4-mm needles in order to facilitate correct rotation without increased IM injections. These patients were also given intensive education on the injection recommendations as summarized in this chapter. Control patients were informed of the presence of LH and were told that injections should not be given into LH. They received usual and standard education. In the intervention group, there was a significant decrease of TDD of insulin of approximately 5 IU versus baseline (P = 0.035). There were significant decreases in HbA1c (up to 0.5%) in both intervention and control groups, with no significant differences between groups. A significant number of intervention patients improved their IT habits. The authors concluded that the intervention was effective in both groups, but that intensive education in LH management yielded more rapid and superior outcomes.

ing quadrant to quadrant in a consistent direction (e.g., clockwise) [77]. **A3**

study population fell by an average of 5.6 IU by study close.

up to 97% consistency levels. FITTER issued the following recommendations:

of their original dose [66, 76]. **A1**

trauma. **A2**

64 Ultimate Guide to Insulin

Reusing needles is a common practice of injecting patients, mainly for reasons of convenience and cost-saving. However, a number of studies have linked needle reuse to LH [59, 65, 66, 81–83], especially when the reuse is excessive (≥5 times/needle). Injection pain was associated with reuse in one study [84] although another one disputed these results [85]. Another study found bacterial growth on reused needles and inflammatory changes (skin redness) at injection sites of patients who reused needles [86, 87]. Although local infections or abscesses have not been reported with needle reuse, FITTER recommends against reusing needles, which are labeled by regulatory agencies for single use.
