1. Hypoglycemia Unawareness
Joan P Frizzell Ph.D. RN

2. Hypoglycemia Unawareness
Loss of warning signs and symptoms of hypoglycemia
Decreased counter – regulatory hormonal response to hypoglycemia
Associated failure to treat hypoglycemia

3. Hypoglycemia Most commonly occurs from treatment of Diabetes mellitus
25.8 Million People in the US have DM
8.3% of American People
1.9 million cases diagnosed each year
One third of people are as yet undiagnosed
Direct & Indirect costs exceed $174 Billion

4. Hypoglycemia Defined as glucose level of < 60mg/dl
Associated with specific symptoms and physiologic responses
Symptoms may occur at higher glucose levels in some patients
Symptoms and physiologic responses may be decreased due to repeated episodes of hypoglycemia

5. Etiology Medications Edogenous hyperinsulinism Starvation
Especially those used in the treatment of Diabetes mellitus
Pentamidine, quinine
Edogenous hyperinsulinism
Insulinoma and other pancreatic B cell disorders
Starvation
Endocrine deficiencies
Reduction in secretion of glucocorticoids, growth hormone, glucagons

6. Increased Risk of Hypoglycemia
Patients with Type 1 DM
“Tight” or near normal glycemic control
Approximately 25% of patients with DM have a major hypoglycemic event

7. Risk Factors
Insulin or insulin secretagogue is given in an excessive amount
Insulin or insulin secretagogue is given at the wrong time
Reduction in carbohydrate intake
Glucose utilization is increased
Exercise
Insulin clearance is reduced
Renal disease

8. Diagnosis – Whipple’s triad
Symptoms consistent with hypoglycemia
Low plasma glucose level
Raising plasma glucose level relieves symptoms

9. Glucose Homeostasis
Insulin secretion
Counter-regulatory Hormones

10. Insulin Secretion Daily basilar level Stimulated secretion 40-50 U/day
BS mg/dl
Secreted through glucose metabolism mediated depolarization
Membrane changes promote Ca influx and insulin secretion

11. © 1999 W.B. Saunders Co.
Slide 20.16

12. Insulin Action Insulin dependent glucose transporters
Storage of energy substrates
fats
amino acids
glucose to glycogen
Enhancement of growth factor activity
Increase cellular uptake of K, Phosphorus, and Mg

13. © 1999 W.B. Saunders Co.
Slide 20.17

14. Counter Regulatory Hormones
Glucagon
opposes insulin
Epinephrine
mobilization of glucose stores
Glucocorticoids
decreases peripheral utilization of glucose
Growth Hormone
decreases glucose uptake by tissues

15. Hypoglycemia Responses
Reduced Insulin secretion
Glucose level mg/dl
Counter -regulatory hormone secretion
Glucose level 65 – 70 mg/dl
Secretion of epinephrine is critical for restoration of glucose levels

16. Tkacs, N (2002)

17. Hypoglycemia Symptoms
Neurogenic or ANS responses
Neuroglycopenic responses

18. Tkacs, N (2002)

19. Neurogenic – ANS Responses
Cholinergic
Hunger
Paresthesia
Cholinergic Sympathetic Response
Sweating
Adrenergic
Palpitations
Tremor
Anxiety
Pallor

20. Neuroglycopenic Responses
Behavioral Changes
Irritability
Headache
Confusion
Fatigue
Prolonged Hypoglycemia
Seizure
Coma
Death

21. Nocturnal Hypoglycemia

22. Hypoglycemia Unawareness
Reduced counter-regulatory hormonal responses to hypoglycemia
Impaired gluconeogenesis and glycogenolysis
Reduced physiologic responses to hypoglycemia
Patient unaware of reduced blood glucose
Takes no action to restore normal levels
Possible relationship to use of Beta adrenergic blocking agents

23. Tkacs, N (2002)

24. Reduced Hormonal Responses
Decreased glucagon secretion often occurs in Type 1 DM
Prior episodes of hypoglycemia reduce the threshold for epinephrine secretion
Hypoglycemia unawareness indicates that prior episodes of hypoglycemia have occured

25. Hypoglycemia Risk Reduction
Patient Education and empowerment
Frequent self monitoring
Flexible medication regimens
Blood Glucose Awareness Training

26. Patient Family Education
Signs and symptoms of hypoglycemia
Test blood sugar before driving a car or operating any hazardous equipment
Carry glucose tablets or snack at all times
Teach family members to administer glucagon, if patient is non responsive

27. Treatment Oral treatment with 15 -20 gm of glucose
Appropriate oral replacement includes
½ cup of fruit juice and crackers
½ cup of milk and crackers
After treatment, retest blood sugar in 15 minutes.
If blood sugar is less than 60 mg/dl give an additional source of carbohydrates

28. Urgent Treatment Oral treatment with 20 gm of glucose tablets
Parenteral 25 gm of glucose in a 50% solution
Parenteral 1 mg glucagon

29. Blood Glucose Awareness Training
Developed by
Recognize symptoms of hypoglycemia
Estimate blood glucose level
Compare with self blood glucose monitoring