Ch. 33 Diabetes Mellitus and the Metabolic Syndrome Flashcards
Where is insulin found?
insulin is secreted by Beta Cells which are found in the Islets of Langerhans in the Pancreas
function of insulin
- transporter of glucose from circulation to cells
- w/o insulin, glucose stays in circulation and cells starve
- if there is an excess of insulin, the body will store it
elevated blood sugar
- insulin secreted by Beta cells
- insulin causes glucose to reenter cells
- blood glucose is lowered
decreased blood sugar
- glucagon released by alpha cells
- glucagon stimulates release of glucose from liver
- blood glucose is raised
Glucose
- brain requires constant supply
- hypoglycemia/brain death
- blood glucose level
- ingested
- liver regulation
liver regulation of glucose
- glycogenesis
- glycogenolysis
- gluconeogenesis
when blood sugar drops (like during sleep) the liver releases glycogen so the blood sugar level can stay normal—–> if liver is saturated with glycogen, then glucose is turned into triglycerol (fat cells) which is usually seen in people who have diets high in carbohydrates
glycogenesis
make glycogen
glycogenolysis
breakdown of glycogen
gluconeogenesis
makes glucose out of other sources in the body
BADDDDD
occurs when not enough is consumed and the liver storage is depleted
Insulin
- released by beta cells
- only hormone known to lower blood glucose
- increases transport of glucose into cells
- inhibits gluconeogenesis
- increases protein production (glycemic control for wound healing)
glucagon
- produced by alpha cells
- provides increase in blood glucose during fasting
- initiate glycogenolysis
- regulated by blood glucose level
- increases conversion of amino acids to glucose
Diabetes Mellitus
- hyperglycemia
- impaired glucose regulation
- imbalance - gestational diabetes
- 2 types: type 1 and type 2
Type 1
- onset b/w 10-14 (but can be diagnosed later)
- treated with pump, shots/injection of insulin, organ (pancreas) transplant
- no insulin production
- symptoms 3Ps
- polyuria- increased urine production
- polydipsia- increased thirst- polyphagia- increased hunger (cells starving so they keep signaling )
- other S/S : sweet/fruity breath, weight loss w/o trying, elevated ketones
Type 2
- insulin resistance
- 90-95% of diabetes patients
- most diagnosed over 40, but now in obese children
- multifactorial (genetic, environmental/food)
- treated with oral hypoglycemic agents(stimulate B cells to produce more insulin)
- could result in an insulin dependent diabetic if not controlled
- macrovascular disease
- low levels of HDL (good cholesterol)
What increases risk of Type 2 diabetes
smoking, sedentary lifestyle, overweight, high fat and cholesterol levels,hypertension
DM1
IDDM - Insulin dependent
DM2
NIDDM - non insulin dependent
Can a type 1 diabetic respond to oral anti diabetic medications?
no
plasma insulin levels in type 1/type 2
type 1: absent or low
type 2: normal to high(not enough for the body)
Gestational diabetes
- associated with pregnancy
- insulin requirements increase
- production decreased or same
- can be treated with oral medication but have to be aware of tetragenics(cause birth defects)
Risk factors
- family history of type 2
- age
- gestational diabetes previously
- previous pregnancy w/baby >9 lbs
- impaired glucose tolerance or impaired
- smoking
Which type of diabetes manifests more slowly
type 2: creeps in cant identify short time
type 1: manifests more suddenly
Casual blood glucose
used in the ER and times when fasting blood glucose cant be taken
glycosylated hemoglobin test HgA1C
HgA1C
- best predictor of blood glucose levels over time
- RBC live for 120 days, normally don’t contain glucose, but is blood glucose is elevated for a while they will begin to pick up some of the glucose
diagnostic tests for diabetes
- fasting blood glucose
- oral glucose tolerance
- casual blood glucose
- capillary blood glucose
- urine test
- glycosylated hemoglobin test HgA1C
Management of DM
normalize blood sugar, exercise, diet, insulin, pills, keep lipid levels down (cardiovascular risk), keep Blood pressure down
why is exercising with type 1 risky?
insulin is set for what they need normally so when they exercise it burns up the glucose and they don’t have any stored because they lack storing mechanisms. need to eat complex carbs to prevent a fast and high peak in blood sugar levels.
acute complications
Diabetic ketoacidosis and Hyperosmolar Hyperglycemic Non Ketotic state = hyperglycemia
but can lead to hypoglycemia
DKA
Type 1
- acidosis is result of ketones
- response to stress, illness
- lack of insulin: mobilization of fatty acids —> excess ketone production by the liver
- often initial presentation in the ER
S/S
- nausea
- vomiting
- polyuria
- polydipsia
- dehydration
- mental status change
- Kussmal breathing/rapid breathing
- fruity smell on breath-from ketones
HHNS
type 2 will come in ER with even high blood glucose because of glycosuria and water loss
- stress, infections and trauma cause an increase in release of cortisol thus increasing blood sugars
- NO KETONES
- very dehydrated
- could result in HHNK coma with extremely high glucose levels
hypoglycemia
- insulin reaction
- complication of therapy
- parasympathetic stimulation followed by sympathetic stimulation
peripheral Neuropathy
complication of DM
- somatic neuropathy- feeling in extremities
- autonomic neuropathy- decreased cardiac responses, inability to empty bladder, GI tract, sexual dysfunction
Nephropathy
chronic complication of DM
- affecting the kidneys
- leading cause or ESRD
- end stage renal disease is usually caused by damage to glomeruli where glucose is being filtered
- Microalbuminuria is the 1st renal manifestation
Retinopathy
chronic complication of DM
- affecting the eyes : leading cause of blindness
- due to retinal hemorrhage
Vascular Disease
chronic complication of DM
-macrovascular :coronary artery disease, vascular disease, stroke
and
-microvascular : kidney, eyes, nerves
foot ulcers
- most common complication leading to hospitalization
- neuropathy is a major risk factor
Common Sites:
- back of heel
- great toe
- plantar metatarsal
common infections
- soft tissue of extremities
- osteomyelitis
- UTI
- candidal infections (yeast)
- tuberculosis
why are infections common in DM patients?
- sensory deficits
- macrovascular compromise
- high blood glucose levels can impair host defences
