Microvascular Complications Flashcards
KEY SITES OF MICROVASCULAR COMPLICATIONS: (3)
- Retinal arteries (eyes)
- Glomerular arterioles (kidneys)
- Vasa nervorum (tiny blood vessels that supply the nerves)
FACTORS THAT INFLUENCE RISK/SEVERITY OF COMPLICATIONS: (5)
- Severity of hyperglycaemia
- Hypertension
- Genetics
- Hyperglycaemic memory
- Tissue damage through originally reversible and later irreversible alterations in protein
what is hyperglycaemic memory
How well controlled your glucose has been from the onset of the diabetes- it does not matter if you now have good control, you will still see repercussions if you had poor control at the start
What is the main cause of blindness in people of working age
Diabetic retinopathy
What is 1st stage diabetic retinopathy known as:
Background retinopathy
What is 2nd stage diabetic retinopathy known as:
pre-proliferative diabetic retinopathy
What is 3rd stage diabetic retinopathy known as
proliferative retinopathy
Are microvascular complications reversible?
To an extent, then you’ve fucked it
What happens in 1st stage diabetic retinopathy (3)
- Hard exudates (cheese coloured lipid deposits)
- Microaneurysms (‘dots’)
- Blot haemorrhages
What happens in 2nd stage diabetic retinopathy (3)
- Cotton wool spots, also called soft exudates
- Represent retinal ischaemia
What happens in 3rd stage diabetic retinopathy (3)
- Visible new vessels on disk or elsewhere in retina
What is maculopathy
a specific type of retinopathy that effects the macula, involved in colour vision
What does the macula do
involved in colour vision
What happens in maculopathy (3)
- Hard exudates near the macula
- Same as retinopathy but located around macula
- Can threaten direct vision
MANAGEMENT OF DIABETIC BACKGROUND RETINOPATHY (3)
- Improve glucose control
- Warn patient that warnings signs are present
- Retinal screening annually
MANAGEMENT OF DIABETIC PRE-PROLIFERATIVE RETINOPATHY
- Treatment= PAN RETINAL PHOTOCOAGULATION- burn off parts of the retina using lasers- prevents new vessels forming
What does PRE-PROLIFERATIVE RETINOPATHY show
Suggests general ischaemia
What happens if nothing is done in PRE-PROLIFERATIVE RETINOPATHY
New vessels will grow due to ischaemia
MANAGEMENT OF DIABETIC PRE-PROLIFERATIVE RETINOPATHY
- URGENT pan retinal photocoagulation
MANAGEMENT OF DIABETIC MACULOPATHY
Needs only a GRID of photocoagulation- not PAN retinal, just on the macula
Features of diabetic nephropathy?
- Hypertension
- Progressively increasing proteinuria
- Progressively deteriorating kidney function
- Classic histological features
People tend to die from X problems following this as diabetic nephropathy increases your risk of X problems hugely
cardiovascular
CVS
Histological features in the glomerular cells of kidney in diabetic nephropathy (3)
- Mesangial expansion
- Basement membrane thickening
- Glomerulosclerosis
Incidence of diabetic nephropathy in T1DM?
20-40% by 30-40 years
Incidence of diabetic nephropathy in T2DM?
20-40% by 30-40 years
Difference between T1 and T2DM in epidemiology? (3)
- T2DM is developed at a later age
- Racial factors impact nephropathy risk
- Loss due to cardiovascular morbidity (they die from macrovascular disease)
CLINICAL FEATURES OF DN: (3)
- Progressive proteinuria- use a urine dipstick (nephrotic range >3000mg/24hr)
- Increased BP
- Deranged renal function
STRATEGIES FOR INTERVENTION FOR DIABETIC NEPHROPATHY: (4)
- Control of the diabetes
- Blood pressure control- Antihypertensive treatment
- Inhibition of the RAAS system- ACE inhibitors
- Cessation of smoking
most common cause of neuropathy and therefore of limb amputation in the world is…
Diabetes
vasa nervorum are…
Small vessels supplying nerves
- Small vessels supplying nerves are called ….
vasa nervorum
- Neuropathy results when….
vasa nervorum get blocked
FEATURES OF DIABETIC NEUROPATHY: (6)
- Peripheral neuropathy
- Mononeuropathy (1 nerve effected)
- Mononeuritis multiplex (multiple nerves)
- Radiculopathy (dermatomes effected)
- Autonomic neuropathy
- Diabetic Amyotrophy (part of the muscle effected)
PERIPHERAL NEUROPATHY IS MOST COMMON IN…
Longest nerves supplying feet
PERIPHERAL NEUROPATHY causes a…
loss of sensation in patients
PERIPHERAL NEUROPATHY is more common in…
tall people
Patients with poor glucose control
The danger in PERIPHERAL NEUROPATHY is….
Danger is that patients will not sense an injury to the foot
WE TEST SENSATION IN FEET USING ….
MONOFILAMENT EXAMINATION
What is Charcot’s joint
- Multiple fractures on foot x-ray to diagnose
What is MONONEUROPATHY
- Usually sudden motor loss
Which areas are usually affected by MONONEUROPATHY
- Wrist drop, foot drop
- Cranial nerve palsy
- Double vision due to 3rd nerve palsy
What is PUPIL SPARING 3rd NERVE PALSY
- Eye is usually “DOWN AND OUT”
- (6th nerve pulls eye out and 4th nerve pulls it down)
- Pupil DOES respond to light
In 3rd nerve palsy, if pupil is spared, it’s X or Y, if it’s not spared, it’s probably Z
X - diabetes
Y - a vascular disease
Z - a compressive lesion
Why is the pupil spared in diabetic neuropathy and not a compressive lesion
PS fibres controlling constriction run on the outside of the optic nerve, and are less easily blocked.
However a compressive lesion will block this
MONONEURITIS MULTIPLEX is….?
- A random combination of peripheral nerve lesions
RADICULOPATHY is…?
- Pain over spinal nerves, usually affecting a dermatome on the abdomen or chest wall
AUTONOMIC NEUROPATHY is…?
- Loss of sympathetic and parasympathetic nerves to GI tract, bladder, cardiovascular system
AUTONOMIC NEUROPATHY effects on GI tract? (4)
Difficulty swallowing
Delayed gastric emptying
Constripation/nocturnal diarrhoea
Bladder dysfunction
AUTONOMIC NEUROPATHY effects on CVS? (2)
Postural hypotension- can be disabling Collapsing on standing
Cardiac autonomic supply Case reports of sudden cardiac death
TESTING FOR AUTONOMIC NEUROPATHY:
- Measure changes in HR in response to VALSALVA MANOEVRE
- Normally there is a change in HR
- Look at ECG and compare R-R intervals
What is vasalva manouvre?
Breathing out with a closed mouth and pinched shut nose
What is vasalva manouvre?
Breathing out with a closed mouth and pinched shut nose. normally there is an increase in HR
