Building Competency in Diabetes Education THE ESSENTIALS

BASAL-BOLUS INSULIN THERAPY | 12-75

indicate the importance of changing the infusion sets every 48 to 72 hours. Kerr et al. reported occlusions at less than 72 hours (three days) were rare and independent of choice of insulin analogue (aspart, glulisine or lispro) and the probability of occlusion over five days was 9.2% with aspart, 40.9% with glulisine and 15.7% with lispro 67). Thethi et al. found blood glucose control deteriorated between day two and day five despite an increase in total daily insulin dose from 48.5 +/- 11.8 to 55.3 +/-17.9 units (141.

Table 4. Impact of prolonged infusion set use on blood sugars (106) Day 2 Day 5

p-value

Average daily blood glucose (mmol/L)

6.8

9.1

p<0.05

Fasting glucose (mmol/L)

6.7

8.6

p<0.05

2-hour postprandial glucose (mmol/L)

6.4

9.5

p<0.05

Daily maximum glucose (mmol/L)

11.5

13.5

p<0.05

Time period that glucose was greater than 10.0 mmol/L

14.5%

38.3%

p<0.05

• For most pumps, a “no delivery’” alarm will sound when 2 to 3 units of insulin have been missed. A lack of basal insulin for 4 to 5 hours is generally lower than this, but the deficiency may be sufficient to initiate ketogenesis. Blood ketone testing is invaluable in assessing incremental doses required when unexplained high BG levels occur. Use sick-day guidelines (See Figure 10) to calculate doses required if blood ketone levels are higher than normal (>0.6 mmol/L) ((142). • Clinically, in some cases, sick-day management will be improved if an increased (20 to 50%) basal rate is used in addition to increased correction boluses. • Advise patients to do set changes at times when they can make sure the set is delivering correctly by giving a bolus before a meal and by checking glucose levels after two hours. Changing the site at bedtime is strongly discouraged, as it may be hours before awakening and a problem detected. By then, ketogenesis may have occurred.