Table of contents
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file:///C:/Users/kioskicpm/Documents...poglycemia.pdf
Introduction
- Whenever glucose falls < 3.9mmol/L (70mg/dL), brain does not get enough glucose and sends signals to raise glucose levels:
- Glucagon, Epinephrine, Norepinephrine, Cortisol, Growth Hormone (liver to release glucose)
- Symptoms: (Hyperadrenergic)
- Initially: Sweating, Rapid HR, Anxiety, Hunger, Tremor
- Eventually: Neuroglycopenic symptoms (somnolence, dizziness, slurred speech)
- If continues to decr: Lose conscouslness, focal neurological signs (hemiparesis), seizures
- Causes:
- Hypoglycemic Drugs: Esp sulfonylureas, meglitanides + skip meals or HF/AKI
- Prolongued Exercise (muscles lose glycogen), often delayed hrs after exercise. Esp worse if they have alcohol.
Patients with Diabetes
- Severe Hypoglycemia
- Documented Symptomatic Hypoglycemia
- Asymptomatic Hypoglycemia - esp those that are chronically low (Type I DM), body gets used to low glucose.
- Relative Hypoglycemia - Get used to higher glucose levels, must lower gradually.
Patients without Diabetes
- Very rare, islet cells turn off insulin, and turn on glucagon
- When hepatic glycogen stores exhausted (takes ~8hrs), liver manufactures (gluconeogenesis) glucose
- Causes: (+ glycogen stores depleted)
- Extreme starvation
- Hepatic dysfunction
- Sepsis
- Alcohol suppresses hepatic glucose production
- Cortisol Deficient (Addisons)
- If Hypoglycemic in non-fasting state
- Insulinoma --> very rare
- Exogenous Insulin (or sulfonylurea or meglitonide)
Diagnosis
- Must diagnose hypoglycemia WITH SYMPTOMS
- Whipple's Triad exists
- 1. Hypoglycemic Symptoms
- 2. Low plasma glucose level (by lab! Not glucometer - unreliable at low levels)
- 3. Symptoms resolve with glucose ingestion
Workup
- Considering it is not caused by exogenous insulin.
- If suspecting excess insulin secretion must do workup
- Diagnostic Workup: (ONLY worthwhile in fasting state)
- Plasma glucose
- Insulin + Pro-Insulin
- C-Peitide
- β-hydroxybutyrate
- Sulfonylurea
- These tests must be done during the episode of hypoglycemia (dong this after sugar was given is not helpful).
- Typically patients fast x72hrs, and the above labwork is done every 6hrs until finish (blood glucose < 3.0, or symptomatic)
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- If positive, and suspect insulinoma: need CT for surgery!
Postprandial Hypoglycemia
- Extremely Rare, but frequently missed
- Often seen in patients post bypass surgery
- Report sleepy, shaky after a large meal (hypoglycemia)
- Diagnosis:
- Observe patient + measure plasma glucose when symptoms occur
- Do not do OGTT --> can cause severe hypoglycemia
- Treatment
- Smaller, more frequent meals. (avoid simple carbs)
- More complex carbs w/ protein (peanut butter, etc..)
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