capillary blood glucose (sugar)

Indications

• evaluation of glycemic control in diabetes mellitus
• preprandial & postprandial glucose in patients with multiple insulin injections each day
• 2 hour postprandial glucose when there is a discrepancy between fasting capillary blood glucose & hemoglobin A1c (see glycemic control)

* little evidence that capillary blood glucose is of value in patients with type 2 diabetes not taking insulin

Reference interval

• preprandial target range:
  • 70-130 mg/dL
  • 90-130 mg/dL elderly
    • 90-150 mg/dL if elderly with multiple comorbidities
• 1-2 hour postprandial target range: < 180 mg/dL

Increases

• diabetes mellitus
• see hyperglycemia

Procedure

reading obtained from glucometer

• sticking the side of the thumb produces the least pain
• sticking the earlobe also produces little pain
• alternate site testing may be less painful & more convenient
• finger tip sampling is preferred, due to considerations of blood flow & uptake of glucose by muscle & fat
• blood glucose changes appear 30 minutes earlier in the fingers before other sites

Management

• check blood glucose using fingertips when
  • blood glucose is changing rapidly
    • within 2 hours after a meal, exercise or insulin
  • checking for hypoglycemia
• alternative sites ok to test
  • fasting blood glucose
  • preprandial blood glucose

More general terms

• point of care test
• glucose in blood

More specific terms

• capillary blood glucose fasting

Additional terms

• diabetes mellitus
• glucometer (OneTouch, FastTake, Lifestyle, InDuo, Lifescan, Accu-Check Accu-Check Advantage, FreeStyle, AtLast, InCharge, Prestige, Elite, DEX, Sof-Tact, SideKick)
• glucose (dextrose, D-glucose)
• glucose in serum/plasma
• glycemic control
• hyperglycemia
• hypoglycemia