Building Competency in Diabetes Education THE ESSENTIALS

BASAL-BOLUS INSULIN THERAPY | 12-36

Basal Insulin Selection Physiological basal insulin replacement remains a challenge from both clinician and policy maker perspectives. Despite advances in long-acting analogue (LAA) and insulin pump therapy, funding and clinical practice variations continue to limit access to all options for many Canadians. As the Diabetes Report illustrates, discrepancies across Canada are significant. NPH remains widely used as a basal insulin for initiation of BBI in many parts of Canada (69). The 2018 Guidelines recommendations state: “A long-acting insulin analogue may be used in place of NPH to reduce the risk of hypoglycemia [Grade B, Level 2 for detemir and glargine U100; Grade D consensus for degludec and glargine U300], including nocturnal hypoglycemia [Grade B, Level 2 for detemir and glargine U100; Grade D, consensus for degludec and glargine U300] (1). In early versions of BBI, a single dose of intermediate-acting insulin given at bedtime was used to address 24-hour basal insulin requirements. It is recognized that adequate basal replacement may be difficult to achieve using intermediate-acting insulin, particularly in a single-dose form. Intrasubject and intersubject day-to-day variability of absorption of insulin suspensions of up to 30% has been identified (36). Strategies suggested to minimize this variability include: • Re-suspend (thoroughly mix) the NPH/N mixture well. Significantly different patterns of insulin action between re-suspended and nonsuspended NPH/N have been observed (38). In a study by Jehle et al. it was shown that only 9% of subjects using cartridges of NPH insulin were adequately resuspending the insulin and that tipping and rolling the pen a minimum of 20 times was required for adequate re-suspension (70). • Ensure proper site rotation and rotation within the site is used. Use the largest zone possible within an anatomical area. Divide area into smaller sections. Use the area for one week before moving to the next section. Injections should be 2-3 cm from the previous one (71). • Absorption is typically best and most consistent when the abdominal site is used (53). The arms are the next fastest, but an intramuscular (IM) injection is more likely to occur. The thigh may be selected as a site for NPH/N injections in an attempt to lengthen its duration of action. The buttock site appears to result in a slower, more variable absorption (28,72). An international survey on insulin injection technique found that 1. Intermediate-acting insulin: Single or twice daily doses Single-dose NPH/N: