Diabetes Flashcards
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?
Us and Es (?hypernatraemia)
Glucose (rule out DM)
Plasma:Urine Osmolality (rule out primary polydipsia, urine should be no more that twice as conc)
8hr Deprivation Test (<700)
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 - MODY
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
What is the parameter for diagnosing DM using the OGTT?
> 11.1mmol/l
What is the parameter for diagnosing DM using HbA1c?
> 48mmol/l
6.5%
What are the parameters for ‘Pre-Diabetes’?
Fasting glucose of 5.5-6.9mmol/l
HbA1c of 42-47mmol/l (6-6.4%)
What is required for a Diabetes diagnosis?
Either
Symptoms and ONE positive blood result
Or
Positive bloods on two separate occasions
What advice would you give patients who are diagnosed with Type 1 DM? Give 4 points.
Review and research diet
Try to limit other things contributing to CVS risk
Ensure foot care
Avoid binge drinking (delayed hypoglycaemia)
Name one ultrafast, one medium and one long acting insulin
Ultrafast - Novorapid
Medium - Isophane Insulin
Long - Insulin Glargine
Name a premixed insulin
Novomix (30% short, 70%long)
Describe 2 different regimens to manage T1DM
Basal Bolus - rapid acting at meals and two long acting (determir)
BD - Twice Novomix daily
What could you give patients if they struggle with the insulin regime?
Insulin Pump
Give three important pieces of advice for T1DM regarding insulin
Vary injection site
Change needles
Continue insulin if ill (and replace lost calories with milk)
Describe the 4 step (up) therapy for T2DM
1) Lifestyle and Diet
2) Metformin
3) Dual Therapy (Metformin + another)
4) Triple Therapy or Insulin Therapy
What is Metformin’s action?
Biguanide that increases insulin sensitivity
Give 3 SE of Metformin
Nausea, Abdo Pain, Lactic Acidosis (in renal impairment)
Name a DPP4 Inhibitor. What is it’s action?
Sitagliptin
DPP4 destroys incretins which enhance insulin release
Name a Glitazone. What is it’s action?
Pioglitazone
Increases insulin sensitivity
When are Glitazones contraindicated? What are their side effects?
CI - Osteoporosis, CCF
SE - Hypoglycaemia, Fractures
Name a Sulphonylurea? What is it’s action?
Gliclazide
Increases insulin secretion by binding to ATP sensitive potassium channels, closing them
Name an SGLT2 inhibitor. What is it’s action?
Dapaglifozin
Blocks glucose reabsorption in the PCT
Name a GLP1 analogue. What is it’s action?
Exenatide
Incretin mimics
Name four complications of Diabetes
Vascular disease
Nephropathy
Retinopathy
Neuropathy
Give two eye diseases associated with Diabetes
Diabetic Retinopathy
Cataracts
Describe the pathophysiology of Diabetic Retinopathy
Microvascular occlusion causes retinal ischaemia
Leads to AV shunts, Neovascularisation and Oedema
Describe 3 characteristic features of Diabetic Retinopathy
Microaneurysms - physical weakening of vascular walls
Haemorrhages - when weakened vessels rupture, can be small or large (AKA Flame - track along nerve-fibre bundles in superficial retinal layers)
Cotton Wool Spots - Build up of axonal debris
How would Diabetic Retinopathy present?
Often gradual painless visual deterioration
If haemorrhages - sudden onset of dark, painless floaters which may resolve over several days.
Most Diabetic Retinopathies are not treated, however if they are, give 2 treatment options
Laser Treatment - aim is to induce regression of new blood vessels and reduce central macular thickening
Intravitreal Steroids
Give 4 possible features of foot neuropathy
Reduced sensation in stocking distribution
Absent ankle jerks
Charcot Joint
Claw Toes
How would a diabetic ulcer present?
Punched out ulcer in area of thick callus
Describe 3 non surgical managements of ‘Diabetic Foot’
Regular Chiropody
Bisphophonates
Antibiotics
Hypoglycaemia is classified as <3mmol/l glucose. Majority of times it’s a diabetic cause, but using the mnemonic EXPLAIN, state 7 non diabetic causes.
Exogenous Drugs (ACEI, B Blockers)
Pituitary Insufficiency
Liver Failure
Addisons
Insulinoma
Non pancreatic Neoplasms
Give 3 autonomic and 3 neuroglycopenic symptoms of Hypoglycaemia.
Autonomic - Sweating, Anxiety, Hunger
Neuroglycopenic - Confusion, Drowsiness, Coma
What is Whipple’s Triad?
Symptoms + Hypoglycaemia + Resolution as plasma glucose rises
Describe the pathophyiology of DKA
Without insulin to drive glucose into the cells, the body is forced into starvation state, using ketones for energy and causing acidosis
Name three triggers of DKA
Infection
Non Compliance
Chemo
Name 5 symptoms of DKA
Drowsiness
Vomiting
Dehydration
Abdo Pain
Polydipsia
Describe 3 diagnostic classifications of DKA
VBG pH<7.3
Glucose>11.1mmol/l
Ketonaemia (>3mmol/l) or Ketonuria
Describe a four step management plan of DKA
1) IV 0.9% NaCL - 1L over an hour
2) Insulin at 0.1 unit/kg/h
3) Monitor K+ - ?add to next bag of fluid
4) Start 5% Dextrose infusion when CBG<15
Give 3 complications of DKA
Cerebral Oedema
Hypokalaemia
Aspiration Pneumonia
What is a Hyperosmolar Hyperglycaemic State?
Seen in unwell patients with T2DM
Hx of a weeks dehydration with glucose>30mmol/l
NO KETONE METABOLISM
How would you manage Hyperosmolar Hyperglycaemic State?
Rehydrate slowly
Replace K+ when urine starts to flow
Only use insulin if glucose isn’t reducing
Describe the different between Dry and Wet Gangrene
Dry Gangrene - Black ‘mummified’ toes that often autoamputate
Wet Gangrene - indicates infection
Describe four features indicating Necrotising Fasciitis from Diabetic Foot
Spreading Cellulitis
Black Spots
Dishwater Fluid Appearance
Crepitus (tissue paper sound when pressing - gas gangrene)
Describe two features you are looking for on an X-Ray of a diabetic foot
Osteomyelitis
Gas Gangrene
Why is ABPI generally done on right arm?
Steal Syndrome is more common on the left
You generally stand to the right of the patient
Explain the ABPI value indicating Diabetic Foot
> 1.2
Due to calcification of the peripheral arteries increasing the pressure (NOT because they have superior blood flow to PAD)
Describe the Doppler Sounds of vessels
Monophasic
Biphasic
Triphasic
Monophasic is diseased, and triphasic is healthy (you can hear the elastic recoil in competent vessels)
Using the mnemonic SWOMPD, how would you manage a diabetic foot?
Sepsis
Wound Management
Offloading (Orthotics)
Mechanical (Orthopaedics input)
Perfusion (Lifestyle, Meds, Surgical)
Diabetic Control
What antimicrobials would you use for MILD Diabetic Foot?
Flucloxacillin
What antimicrobials would you use for MODERATE Diabetic Foot?
Flucloxacillin, Ciprofloxacin and Metronidazole
What antimicrobials would you use for SEVERE Diabetic Foot?
Piperacillin, Tazobactam and Vancomycin
What investigation should you do if atypical features for diabetes?
C Peptide
Give three scenarios where HbA1c cannot be used
Haemoglobinopathies
Children
CKD
What is impaired glucose tolerance?
OGTT more than 7.8 but less than 11.1
Describe T1DM monitoring
HbA1c three monthly
Self monitoring QDS
Aim for 4-7mmol/l
What medication could you add to overweight patient’s T1DM medication?
Metformin
Describe the sick day rules for diabetes
Monitor CBG more frequently
Have access fo phone
Don’t change hypoglycaemic/insulin dose (stop metformin if dehydrated)
Can consider corrective dose if rising glucose/insulin - 10-20%
What diet measures should you encourage in T2DM
High fibre
Low glycaemic index
Low fat
Target weight loss 5-10%
When should you start dual therapy in T2DM?
When HbA1c is 58mmol/l
With what oral hypoglycaemic agent are you permitted a higher target HbA1c?
Sulphonylureas (eg Gliclazide) as can cause hypoglycaemia
How can the GI side effects of Metformin be minimised?
Titrate up slowly
Modified release
If Metformin is contraindicated what can be used first line?
Gliptins (DPP4 inhib)
Glitazones
Gliclazide (Sulphonylureas)
Can use Glifozins if CVD profile
What should be added to Metformin in patients with significant cardiac history?
Glifozins (SGLT2 inhib)
When can GLP1 analogues be trialled?
If failure of triple therapy and insulin
Or unsuitable for insulin
What are the recommended adjustments during Ramadan for diabetic patients?
High carbohydrate meal before sunrise
Splitting oral hypoglycaemic dose so majority is post sunrise
Regular monitoring
What are the DVLA rules regarding Diabetics
Have to have no hypoglycaemic episodes and have full glycaemic awareness if on insulin
HGV drivers must also provide regular glucose monitoring
Name three GI neuropathic manifestations of diabetes
Gastroparesis
Chronic Diarrhoea
GORD
Describe diabetic foot screening
Annual screening for pulses and sensation
If moderate to high risk of diabetic foot - refer to local diabetes centre
How would you manage Hypoglycaemia?
Alert - quick-acting glucose/glucogel, use of hypobox
Unconscious - IM glucagon, or if good access 20% glucose
At what BGC do you experience neuroglycopenic symptoms?
<2.8
What should be done about patients long-term insulin during DKA?
Stop short-acting, continue long-acting
When has a DKA resolved?
pH>7.3
Bicarb>15
Ketones<0.6
Can start short-acting once eating and drinking
If not resolved in 24h - endocrinologist
What is the process behind Hyperosmolar Hyperglycaemic State?
Osmotic Diuresis
Why should you give VTE prophylaxis in HHS?
Hyperviscocity can result in MI/Stroke
Why is HHS more deadly than DKA?
Happens gradually over a few days therefore electrolyte disturbances are normally more severe
Name three criteria to indicate HHS
Marked Hypovolaemia
Serum Osmolaltiy > 320 (high osmolality)
No ketonaemia
When should insulin be administered in HHS?
Only if significant ketones or glucose refractory to fluids
Glucose between 10-15 is satisfactory
Why should fluid be administered carefully?
Risk of Cerebral Pontine Myelinolysis due to fluid shifts
aim to give 3-6L over 12h
Describe the water deprivation test for Diabetes Insipidus
Prevent patient from drinking and take hourly osmolalities
After deprivation : Cranial and Nephrogenic Insipidus still have low urine osmalality
Primary Polydipsia has high (as can concentrate urine)
High concentration after desmopressin = cranial
