diabetes Flashcards
How can diabetes be diagnosed? (3 ways)
- random blood glucose test over 11.1 with symptoms
- fasting glucose >7, if theyre asymptomatic you need two >7
- Hba1c> 6.5%
Give 5 symptoms of diabetes mellitus?
- tiredness
- frequent UTIs
- Weightloss (T1 only)
- Polyurea
- Polydipsia
Describe the presentation of decompensated ketoacidosis?
- onset over 24 hrs
- PMH T1 diabetes, recent precipitating factor
- polyurea and poly dipsia
- N+ V
- Altered mental state
- weakness
- lethargy
- hyperventilation
- pear drop smell on breath
- dehydrated and volume deplete on examination
What may precipitate DKA? (4)
- Infection.
- Discontinuation of insulin (unintentional or deliberate).
- Inadequate insulin.
- Cardiovascular disease - eg, stroke or myocardial infarction.
- Drug treatments - eg, steroids, thiazides or sodium-glucose co-transporter 2 (SGLT2) inhibitors.
How should DKA be investigated? (group into diagnosis, finding cause and assessment of severity/ complications)
- To diagnose: Blood glucose, blood ketones, urine dip for ketones, ABG showing low bicarbonate (metabolic acidosis)
- To asses severity: U&E- for dehydration and hyperkalaemia, also urea and creatine raised if AKI, 12 lead ECG, CT/ MRI of head, anion gap raised
- to find cause: blood cultures, urine dip, CXR to look for infection
Describe and explain serum osmolality, K+ and Na+ changes in DKA?
- K+ usually high due to acidosis meaning H+ going into cells and K+ coming out, however may be low due to osmotic diuresis
- Osmolality is low due to glucose and ketones causing osmotic diuresis, which is also why Na+ conc seems high or normal. Can be low as body compensates by letting sodium go
Describe the management of DKA in detail
- Fixed rate IV infusion of insulin dose of 0.1 units/ Kg bodywieght every hour
- IV fluids to rehydrate: 1st bag= 1L normal saline over an hour, then 1L normal saline with K= over 2 hrs, then same then 1L NS w/ K+ over 4 hrs then same again, then 1L NS w/ k+ over 6 hrs. Reason for this is the insulin will cause cells to uptake K+ and cause hypokalaemia.
- Monitor closely (every hour) and if targets in HCO3- increases and ketone decreases are not met then increase the insulin
- When blood glucose is over 14mmol/l add 5% dextrose solution infusion to prevent hypo, continue until eating and drinking normally
- treat complications
When does hyperosmolar hyperglycaemic state/ syndrome (HSS) occur?
It occurs in T2 diabetes when blood glucose levels are allowed to be very high for a sustained period of time, causing an osmotic diuresis and so loss of water meaning high serum osmolality. There is no ketoacidosis as there is still a basal level of insulin they respond to sufficient to prevent ketoacidosis but too low to prevent hyperglycemia.
What could cause HHS?
- infections
- inability to take medications
- hypo/hyperthermia
- MI
- Medications
- undiagnosed/ first presentation of diabetes
- Many others
How is HHS present?
With severe dehydration, fast deterioration, focal or global neurological dysfunction, often PMH of diabetes, N+V, lethargy, seizures
How is HHS treated?
- Fluid resus: 0.9% normal saline, can use hypotonic (0.45%) if serum osmolality not going down, however this is rare. You dont want osmolality to decrease too fast (>10mmol/l/hr)
- Fixed rate iv infusion of insulin- 0.05 units per kg per hr
- monitor closely (blood biochemistry as well as neuro function)
Describe 3 early and 3 late signs of hypoglycaemia
early= hungry, sweats, tremor, palpitations, shaking late= confused, headache, drowsy, slurred speech, coma
Describe treatment of hypoglycaemia if theyre conscious and orientated
Oral glucose (dextrose tablets, 150-200ml fruit juice/ original lucozade/ glucojuice) with complex carbs later (bread etc)
Describe treatment of severe hypoglycaemia (unconscious or unable to swallow)
- Iv dextrose (120-200ml 20% solution)
- or IM glucagon often given in community
Describe the diagnosis criteria for DKA and HHS
DKA: acidaemia (ph<7.3 or hco3 <15) and hyperglycaemia (>11.1) and ketonuria (++) or ketonaemia (>3)
HHS: hyperglycaemia >30, no acidosis, no ketosis, serum osmolality >320
What is Diabetes Insipidus?
Reduced ADH secretion/kidney response to ADH causes passage of large volumes of dilute urine
Give 3 symptoms of Diabetes Insipidus
Polyuria
Polydipsia
Dehydration
Give 3 causes of Cranial DI
Congenital (ADH genetic defects)
Tumour
Trauma
GIve 3 causes of Nephrogenic DI
Inherited
Chronic Renal Disease
Drugs (Lithium, Demeclocycline)
What 4 investigations could you do if you suspected DI?
U&Es
Glucose (rule out DM)
Urine Osmolality (rule out primary polydipsia)
8hr Deprivation Test
How would you treat Cranial DI?
Desmopressin
How would you treat Nephrogenic DI?
Treat underlying causes
NSAIDs (Prostaglandins locally inhibit ADH)
Bendroflumethiazide (inducing hypovolaemia may kickstart RAAS)
Describe the pathophysiology of Type 1 DM
Onset in childhood
Autoimmune destruction of pancreatic B cells
HLA association
Describe the pathophysiology of Type 2 DM
Decreased insulin secretion/increased insulin resistance
Associated with obesity/sedentary lifestyle
No HLA association
There is an autosomal dominant form affecting young people
Give 4 other causes of DM
Steroids
Pancreatitis
Cushings Disease
Glycogen Storage Disease
What is the triad of DM symptoms
Polyuria
Polydipsia
Weight Loss
What are the parameters for diagnosing DM in terms of Venous Glucose?
Fasting >7mmol/l
Random >11.1mmol/l