Neonatal hypoglycaemia Flashcards
(30 cards)
How does glucagon and insulin work in metabolism?
Glucagon is released by the alphas cells in the pancreas when blood sugar is too low, and causes…
Converts glycogen to glucose and creates glucose (inhibited by insulin and somatostatin (inhibits both insulin and glucagon). Part of sympathetic- stress-fight or flight
Insulin released beta cells in pancreas when blood sugar too high, and causes… glycogenesis, lipogenesis,, decreases glycogenolysis, stimulates uptake + use of glucose by muscle and connective tissue cells
Insulin is formed from amino acids?
True
Insulin reduces blood glucose levels?
True
glucagon reduces blood glucose levels?
False
Secretion of insulin is stimulated by low blood sugar levels?
False
Secretion of insulin is stimulated by gastrin?
True- because gastrin is produced when you eat, and t
The hypothalamus is involved in the secretion of insulin?
False, the pancreas is
Insulin secretion is decreased by sympathetic stimulation?
True
What is gluconeogenesis?
Body converts non-carbohydrate sources (like amino acids) in our liver into glucose
What is lipogenesis?
Synthesis of fatty acids and storage of fat in adipose tissue
What is glycogenesis?
Conversion of glucose to glycogen, especially in liver and skeletal muscles
What is glycogenolysis?
Breakdown of glycogen into glucose
What is lipolysis?
Breakdown of fat and other lipids by hydrolysis (reaction with water) to release fatty acids
How do healthy newborns regulate their blood sugar?
Healthy newborns initially use glucose in their blood to provide energy, when this is used they then break down their brown fat stores into lactates and ketones to provide energy, until feeding established
What is neonatal hypoglycaemia?
Plasma glucose conc. below 2.6 mmol/l (can vary per trust)
Insufficient circulating glucose to meet the metabolic demands of the body, particularly the brain
May be symptomatic or asymptomatic
Cerebral blood flow becomes deranged below 2.0 mmol.l
Don’t take BMs until 2 hours after birth- it will be low
What infants are at risk of neonatal hypoglycaemia and why?
Premature- because brown fat stores aren’t there and developed until 3rd trimester
IUGR/SGA- low brown fat reserves
Sepsis- body working harder to fight infection
Hypothermic- needs extra glucose and oxygen to keep warm
Babies of mothers with IDDM/GDM
Perinatal stress/asphyxia
Inborn errors of metabolism, e.g. PKU
Beckwith-Wiedemann Syndrome (overgrowth syndomr-macrosomia)
What are the general symptoms?
Abnormal cry
Poor feeding
Hyporthermia
What are the cardio respiratory symptoms?
Tachypnea
Apnea
Cyanois
What are the neurologic symptoms?
Tremors/jitteriness Irritability Lethargy Hypotonic Seizure
Why does neonatal hypoglycaemia occur in preterm infants?
Majority of glycogen stored in 3rd trimester
Brown fat is laid down in the last few weeks of the pregnancy
At TERM 5-8% of liver and muscle weight is glycogen storage
Available stores rapidly depleted
Immature counter regulatory response to low glucose concentration
Why does neonatal hypoglycaemia occur in SGA babies?
Low glycogen and fat stores
Inadequate metabolic control
Chronically stressed fetus may use most of the placentally transferred glucose for growth and survival
Why does neonatal hypoglycaemia occur in the infant of a diabetic mother?
Glucose crosses placenta/insulin does not
Fetal glucose level 70-80% of mother’s
Infant produces insulin in response to higher blood sugars
At cord clamping, glucose supply is removed but insulin production in infant remains elevated
May take several days to down regulate insulin production
How can it be prevented and treated?
Keep babies warm Identify at risk groups Follow local guidelines Keep warm and dry Feed within 60 mins of delivery Frequent feeding, at least 3 hourly Supportive feeding Appropriate monitoring Staff competent when blood sampling Measure blood glucose before 2nd feed Glucose gel- needs feeding as well EBM/formula Naso-Gastric tube Intravenous glucose
Local trust blood glucose measurements?
Use national guidelines for exam
