Diabetes Complications Flashcards
What are the Sx of peripheral Arterial disease?
asymptomatic
claudication (leg cramping relieved at rest)
leg pain at rest
ulceration
gangrene
What is an abnormal ABPI?
ABPI = anke-brachial-pressure index)
ABPI < 0.9 suggests arterial disease
ABPI < 0.5 suggests severe arterial disease
What are the general complications of DM?
- metabolic (acute vs chronic)
- vascular
What acute metabolic complications can be used by DM?
- DKA
- hyperosmolar hyperglycaemic state (HHS)
Why does DKA occur in T1DM?
Complete deficiency in insulin production (no suppression of ketosis generating ketone bodies)
Compensatory hormones released (GCG, catecholamines, GH)
Acidosis results from ketone bodies
What is the pathophysiology in DKA that results in the Sx?
insulin deficiency -> ketosis -> acidosis
insulin deficiency -> hyperglycaemia -> osmotic diuresis -> dehydration
Which electrolytes are depleted/lost through osmotic diuresis in DKA?
- (water)
- Na+
- total K+ (ICF+ECF)
- Cl-
- Ca2+
- PO4
- Mg2+
What are the preliminary (resuscitation) steps in Mx of DKA?
Step 1 in Mx
- insert 2x IV cannula (large bore) for fluid resuscitation
- FBCs, U&Es, BM, lactate, VBG and blood culture
- urinalysis, ECG, CXR, urine culture (also check for other infective sources)
What investigations should be performed in DKA?
- BM
- Glucose (venous blood test)
- ketones
- ABG
- osmolality
- MSU
- blood cultures
- ECG
- amylase
- CXR
How is DKA clinically managed?
- sliding scale of insulin
- fluid resuscitation
- correct metabolic abnormalities
LOOK FOR AND Rx PRECIPITANTS
What fluid resuscitation steps should be taken for DKA?
Step 2 in Mx
NaCl saline 0.9% (without K+)
1L over 10-15 mins
NaCL 0.9% (without K+)
1L over 1hr
What clinical steps should be taken to correct the hyperglycaemia?
Step 3 in Mx
- prescribe IV insulin at a fixed rate of 6 units/hr via infusion pump
- if BM < 14mmol/L then infuse 10% glucose at 100ml/hr and 0.9% saline
then reduce IV insulin rate to 3-5 units/hr
What is the on-going management for DKA?
- Hourly MEWS and BM testing
- hourly fluid balance
- check electrolytes via VBG (especially K+)
- Catheterise if oliguric
- Adjust insulin so glucose is falling at rate of >3mmol/L until <14mmol/L
- Then at BM <14mmol/L, infuse 10% glucose along with insulin at 6 units/hr
- refer to DM team for early input
What is the hyperosmolar hyperglycaemic state?
HHS
= marked hyerglycaemia (>30mmol/L) without significant ketosis or acidosis
There is usually dehydration with some reduced consciousness (GCS)
How is HHS defined clinically?
hyperglycaemia, BM > 30mmol/L
plasma osmolality > 320 mOsm/L
What is the epidemiology of HHS?
- 83/1000 in total population
- higher in Afro-Carribean population
What are the presenting/clinical Sx of HHS?
- elderly
- confused
- vomiting
- dehydration
- pyrexia
- focal neurology
- COMA
What is the Mx for HHS?
similar to DKA
- Be more cautious with fluid replacement
- give less insulin
- MUST use prophylactic heparin
- low threshold for central venous line insertion
- maintain glucose, such that is doesn’t change >10mmol/L/24hr
How may insulin delivery change post-HHS?
may need to switch to subcutaneous (SC) insulin for 2 months post-HHS
What are the chronic complications of DM?
MICROVASCULAR
- nephropathy
- retinopathy
- neuropathy
MACROVASCULAR
- CHD/CVA
- peripheral vascular disease
- hypertension
What is the pathophysiology for vascular complications in DM?
- leakage of PAS POSITIVE glycated proteins
- increase in ECM
- hypertrophy and hyperplasia of endothelium
- acute reversible alterations in metabolism
- cumulative irreversible change in proteins and nucleic acids
How can chronic uncontrolled hyperglycaemia result in cellular damage?
MITOCHONDRIAL OVERPRODUCTION OF ROS
stimulated PARPs in nucleus (increased DNA damage)
suppression of GAPDH and other proteins
Also creates NAD+ excess, which is damaging
results in activation of NF-kB proteins and cellular stress and death
How are glycation products made in DM?
non-enzyme linked reaction
excess of glucose in blood will eventually attach to the plasma proteins (e.g. Hb) over time
What are the cellular consequences of glycan product accumulation?
REDUCED
myo-inositol synthesis (signalling molecule, PI3K)
INCREASED
- vascular permeability
- vasoactive hormone production
- basement membrane synthesis