Hypoglycemia Flashcards
1
Q
4 Defenses Against Hypoglycemia
A
- 1- dec insulin secretion when low blood glucose (inc glycogenolysis, gluconeogenesis, lipolysis and eventually proteolysis - protein breakdown)
- 2- glucagon secretion - main effect is inc hepatic glucose production
- 3- epi inc (becomes critical when glucagon deficient - maybe pancreas removal or Type 1 DM); epi inc hepatic glucose production and dec glucose utilization in
peripheral tissues - 4- GH and cortisol (delayed) - also inc hepatic glucose production and dec glucose utilization
2
Q
Autonomic v. Neuroglycopenic Symptoms
A
- Autonomic - anxiety, tremor, palpitations, pale, sweating, hunger, paresthesias
- Neuroglycopenic - headaches, blurred vision, weakness, fatigue, slurred speech, behavior change, focal neuro deficit, sz, coma, LOC, confusion
3
Q
Progression of Hypoglycemia by Serum Glucose
A
< 80 - Dec insulin
65-70 - Inc glucagon
65-70 sustained - Inc epi (critical) then later inc GH/cortisol (involved but not critical)
< 60 - Neurogenic, autonomic symptoms
< 50 - Neuroglycopenic
< 40 - Lethargy, combative
< 30 - Coma, sz, brain damage, death
4
Q
5 Categories of Hypoglycemia
A
- Severe - requires assistance
- Symptomatic
- Asymptomatic - glucose < 70 w/o symptoms
- Probable symptomatic - symptoms w/o measurement
- Pseudohypoglycemia - symptoms w/ glucose > 70
5
Q
5 Causes of Hypoglycemia in Diabetics
A
- Excessive insulin dose (use rapid instead of basal), wrong timing
- Dec exogenous glucose (fasting, missing meal)
- Inc insulin-indep glucose use (exercise)
- Inc insulin sensitivity - inc w/ sleep, tight glycemic control, wt loss
- Dec endogenous glucose production (alcohol ingestion - suggest eating w/ drinking)
6
Q
Tx for Mild v Severe Hypoglycemia in Diabetics
A
- Mild - RULE OF 15
- 15 g fast acting carbs (OJ, table sugar, glucose tablets, lifesavers, honey, gels, non-diet soda)
- If do NOT improve in 15 min … give another 15 g
- Severe - cog impairment (swallowing may be impaired so no oral - aspiration risk); IV glucose or glucagon kit (IM or subQ injection)
7
Q
Diagnosis of Hypoglycemia in Non-Diabetic
A
- No set lower limit as in DM (variable)
- Dx - Whipple’s Triad
- 1- Signs/symptoms suggestive of
- 2- Low plasma glucose corresponds to symptoms
- 3- Resolution of symptoms when glucose corrected
8
Q
Non-Diabetic Causes of Hypoglycemia
A
- Meds - alcohol, insulin, pentamides, quinine, sulfonylureas, haloperidol
- Insulinoma - 90% benign; 10% associated w/ MEN1; rare; autonomic insulin secretion
- Factitious - inject self or child OR malicious (inject insulin w/ intention to harm)
- Renal Failure
- Severe Liver Disease
- Counter-reg hormone def - adrenal deficiency OR hypopituitarism (dec GH, ACTH)
- Malnutrition
- Tumor-induced - secrete IGF-II or other insulin-like factors
- GISTs, mesenchymal tumors, HCC, adrenocortical tumors, leukemias/lymphomas
- Sepsis - bacteria may consume glucose
- NIPHS
9
Q
Insulinoma Dx and Tx
A
- 72 hr supervised fast; at end meas glucose, insulin, C peptide (endogenous - insulinoma), pro-insulin and beta hydroxybutyrate (inc hydroxybutyrate if low insulin; opp)
- Screen for oral agents (factitious)
- Can give glucagon and look for response (means glycogen stores)
- Surgery is curative if single/benign; octreotide, Ca channel blockers, etc
10
Q
NIPHS
A
non-insulinoma pancreatogeous hypoglycemia syndrome
- RARE islet cell hypertrophy or Langerhan’s neoformation
11
Q
Post-Prandial / Reactive Hypoglycemia (dx, causes, tx)
A
- Dx - mixed meal testing or oral glucose tolerance test
- May see after gastric bypass (beta cell hyperplasia), pre-diabetes, congenital enzyme deficiencies, alimentary (late dumping syndrome - rapid motility/glucose absorption THEN inc insulin)
- Many treated w/ diet modification