Hypoglycemia Flashcards
What is hypoglycemia?
Low glucose
What organs help control glucose homeostasis?
Pancreases, Liver, Adrenal Glands, Kidneys and Skeletal Muscles
What does euglycemic mean?
Normal glucose
How does the pancreas effect glucose regulation?
Alpha Cells - glucagon into the blood stream
Beta Cells - insulin into bloodstream
Gamma Cells - somatostatin in the pancreas
What is the main function of the endocrine pancreas?
Regulate blood glucose levels
-Insulin and glucagon important for feedback control in maintaining normal blood glucose
What effect does insulin have in the bloodstream?
Glucose lowering - tells body to store it
Glucose increases, insulin is released from the pancreas
Inhibits gluconeogenesis and glycogenolysis
Promote uptake glucose into cells, glycogenesis and inhibit glucagon secretion
What is the function of glucagon?
Glucose elevating
Catabolic secretion from a cell in fasted state
Stimulate glycogenolysis in liver and skeletal muscle
stimulate gluconeogenesis in liver
What is the livers’ role in glucose regulation?
Metabolism and storage
-gluconeogenesis, glycogenolysis and glycogenesis
Need more than 30% hepatic mass to maintain euglycemia
Glucose soluble, blood, glycogen insoluble and stored in liver
With liver failure = hypoglycemia
What is gluconeogenesis?
Formation of glucose (non-carb sources - lactate pyruvate, amino acid, glycerol)
What do stress hormones like glucagon and cortisol stimulate?
gluconeogenesis - glucose elevating
(insulin inhibits it)
What is glycogenesis?
Formation of glycogen
Glucose lowering (stored)
-glucagon inhibits it
What is glycogenolysis?
Glycogen in liver broken down to glucose for utilization
-Stimulated by glucagon
-Inhibited by insulin
What is considered hypoglycemia?
Glucose <60mg/dl
-Insulin stops being secreted
-Release counterregulatory hormones (glucagon, cortisol, epinephrine, growth hormones)
What are some reasons glucose may be low?
Excess insulin
Glucagon
Liver failure
Cortisol deficiency (Addisons/Hypoadrenocortisim)
Sepsis
Juvenile (hunting dog/toy)
Neoplasia
Xylitol toxicity
Insulin overdose
Spurious
What are some clinical signs of hypoglycemia?
Lethargy, weakness, ataxia, bizarre behavior, seizure and comma
What diagnostic test should be performed on a hypoglycemic patient?
Consider signalment 1st: young? Not eaten?
Ultrasound - look for insulinoma
-May also look at rads or CT
Bile Acids - Liver function/shunt
Basal Cortisol - Addisons
Insulin and Glucose retest
How can a paired blood glucose and insulin help?
Measure insulin when BG <60mg/dl
BG<60, insulin > normal = insulinoma
BG<60, insulin upper 50% RR = insulinoma
BG<60, insulin lower 50%RR = May be insulinoma
BG<60, insulin below normal = not insulinoma
How do you treat a stable hypoglycemic patient?
Diet (toy or young or insulinoma)
-High fat, protein and complex carb, small meals
-Glucocorticoids (insulinoma, hypoadreno) - prednisone
-Diazoxide (insulinoma)
-Surgery (insulinoma)
How do you treat a patient in acute hypoglycemic crisis?
50% IV dextrose IV 1ml/kg
Dilute 50% dextrose because caustic to vein
Karo syrup on gum if seizing
-Dextrose thick, not under skin
How do you treat if an insulinoma induced the hypoglycemia?
Stabilize with IV dextrose
IV dextrose slowly so that further insulin release not stimulated
IV dexamethasone
Glucagon oppose effect of insulin Rasing blood glucose
Stablize hypoglycemia in crisis
Surgery needed to treat (complications like pancreatitis and DM can occur)
What is the prognosis for insulinoma?
Short term good 1-2yr with surgery
Medical 6 months
Long term
guarded to poor
Metastasize
