CLINICAL- DIABETES Flashcards
Diabetes is the fifth most common cause of death in the world!! Around ______ people between 20 and 79 have their death attributed to diabetes
1 in 8 people
Type 1 diabetes is the autoimmune destruction of pancreatic B cells. What are present in 85-90% of people that cause destruction of these cells?
Islet cell antibodies
Flag to the immune system to destroy these.
How long is life expectancy said to be decreased by for people with type 1 diabetes?
Reduced by 20 years
It’s becoming particularly common in children under 5 now
What happens in terms of insulin secretion in Type 2 diabetes?
Firstly HYPERINSULINAEMIA: body compensates for insulin resistance by increasing insulin secretion from Beta cells (lots of insulin)
Then HYPERGLYCAEMIA: resistance to insulin increases, beta cells can’t produce enough insulin to keep up, glucose levels rise
This all leads to beta cell failure. Glucose levels really badly controlled. Person has to go from oral treatment to insulin injections. Type 2 diabetes present
How long is life expectancy reduced by for people with Type 2 diabetes?
By approx 10 years10-15% of people with diabetes have Type 2
List 5 of the less severe signs and symptoms of diabetes?
Thirst
Polyuria (frequent weeing)
Lethargy Visual disturbance (getting balance of fluid and glucose in eye: some patients say it’s better some worse)
Urinogenital infection
List 3 of the more severe symptoms/ complications with diabetes?
Diabetic Ketoacidosis with type 1
Hyperosmolar hyperglycemic state with type 2
Diabetic foot ulcer
Diabetic retinopathy
Myocardial infarction
To confirm a diagnosis of diabetes, what should blood glucose be when fasting?
7.0 or over
To confirm a diagnosis of diabetes, what should blood glucose be 2 hours after a glucose load?
11.1 or over
We can use HbA1c to diagnose diabetes. What value must this be?
48 mmol/mol or over
Remember these units!!
What percentage of people are currently undiagnosed with diabetes?
50% of people. The need for regular screening is therefore very important
How often should someone with diabetes be reviewed?
ANNUALLY- once a year They do retinal (eye) screening, nephropathy screening (kidneys) Hypertension screening, vascular disease examination (fatty deposits in blood vessels) Neuropathic foot problems are often ignored- not good!!
In a trial, intensive insulin therapy was seen to cause a 1-3 fold increase in what?
Severe hypoglycaemia The more hypos you have, the more the body starts to think this is normal so doesn’t give out any signals before it- people can just fall unconscious unexpectedly But this tighter control of blood glucose slowed the onset of retinopathy (eyes), nephropathy (kidneys), and neuropathy (feet)
What percentage of people with diabetes also have depression because of the effects it can have on emotions?
50% 5-10% on an antidepressant
What is the recommended target range for fasting blood glucose?
4-7 mmol/L
With insulin treatment we aim to achieve BG in this range
What blood glucose do we aim for 2 hours after a meal?
Under 8.5 mmol/L
If we have achieved good glucose control with insulin, what should our urine test come out as?
Negative
What is the target HbA1c range for people with diabetes on insulin?
48-58 mmol/ mol
We aim for 53 mmol/mol
What does porcine insulin differ to human insulin by?
1 amino acid
It is not linked to antibody formation (antibodys won’t be produced against it)
How is human insulin produced?
By enzymatic modification of porcine (pig) insulin
Can use E Coli or Yeast to do this
When may people be out on insulin injections?
When lifestyle and oral therapy haven’t worked
Poor control of diabetes- can be either symptomatic or asymptomatic
Pre and post operatively (remember from surgery topic we can put them on IV insulin)
Infection
Myocardial infarction
Steroid therapy
Pregnancy
What does basal insulin mean ??
Long acting insulin that helps you control blood sugar between meals and during sleep
What does bolus insulin mean?
Insulin that helps you control blood sugar from meals (so managing the spikes after meals- will be shorter acting)
What is a basal- bolus insulin regimen?
Injecting a long acting analogue form (or intermediate acting) of insulin to control blood glucose levels through periods of fasting (I.e between meals and sleeping)
And seperate injections of short acting insulin and rapid acting analogue insulin to control spikes in blood glucose levels after meals
Intermediate human insulin injections, used as basal insulin (to cover you throughout day), last for how long?
May only be active for around 8 hours
But provide a higher peak in insulin action that modern basal insulin
How long may modern basil insulin last?
Can provide up to 24 hour cover
But lower levels than intermediate human insulin
Flat and stable action profile
Degludec is an ULTRA long acting insulin with very slow absorption. What causes this slow absorption?
At the injection site Degludec forms soluble hexamers
From here monomers gradually separate and get into blood stream
Long acting insulin: Zinc suspension {Hypurin} has an onset after 3 hours, and a peak at 6-14 hours (lasts for 24-28 hours so v long action!)
Why is it important to consider onset and peak time?
It’s especially important to consider this in hospital setting especially when busy, as the slower onset means that you can give it earlier and it will still be delivered on time
What are some of the differences between long acting insulin analogue and long acting isophane?
Analogue clear in appearance, isophane is cloudy
No peak with analogue, peak for 2-12 hours with isophane
Both last for 24 hours
There is a risk of night time hypos with isophane insulin
Example of long acting insulin analogue ?
Glargine
Detemir
Degludec
Examples of isophane long acting insulins?
Insulatard
Humulin I
Insuman basal
Hypurin
We need to shape our insulin to the amount of carbs we eat. What type of insulin would be needed after a High carbohydrate meal ?
Rapid acting insulin
Fast acting insulin analogue:
Rapid onset of action: 5-10 mins
Peak : 1-2 hours
Duration : 4-5 hours
Can inject this immediately before or after food
Soluble insulin:
Rapid oneself of action: 30-60 mins
Peak reached: in 1-5 hours
Duration of action: 7-8 hours
Give 30 mins before food
What are the advantages of pre-mixed insulin?
Good for patients needing a simple insulin treatment plan
E.g. If they’re elderly, have poor vision, or are just starting insulin therapy.
They contain a basal (long acting) component and a short acting component.
Why is premixed insulin sometimes called biphasic insulin??
Because premixed injections contain both prandial insulins (short acting human insulin and rapid acting insulin analogues) and basal insulin: so two types if insulin therefore called biphasic
Biphasic (pre mixed) insulin examples?
Biphasic analogues: novomix 30, Humalog mix 25
Biphasic insulin: Humulin M3
What are the three possible regimens with premixed insulin?
Once a day with largest meal
Twice daily with dinner and breakfast
Three times daily with each meal
Therefore if you saw this prescribed at bed time you would question it!!
How do we choose an insulin regimen for someone??
There’s no correct regimen for all people
We need to take into account lifestyle and eating habits when deciding which to choose
Most common regimens: biphasic analogue mix (the premixed ones) and basal bolus
Twice daily (BIPHASIC) insulin regimens are commonly used. What do these consist of?
Premix (biphasic) insulin/ analogue: e.g Humulin M3, Novomix 30, Humalog mix 25
Short acting component: controls rise in BG after breakfast and evening meal
Long acting component: maintains glycemic cit risk from lunch until early evening, and then from late evening to next morning; so you can see it must have slower onset than short acting as it doesn’t kick in for several hours after
With twice daily regimens the total daily requirement are usually split in a 2/3 to 1/3 ratio. What does this mean?
So if you were using Novomix 30: this is 30 units. Need to split in a 2 thirds to 1 third ratio:
20 units given at breakfast
10 units given at dinner
Doesn’t have to be like this: can give 15 units twice a day!!
What can be given in between meals with twice daily regimens to prevent Hypoglyceamia?
Snacks!!
The fact this is needed indicates twice daily (biphasic) regimens have poorer control
How do basal bolus regimens work?
Long acting insulin usually given at bedtime : but can be given at any time of day as long as it’s the same time !!
Short acting then usually given at breakfast lunch and dinner, but patient can adjust their short acting insulin dose according to blood glucose level, exercise and carbohydrates eaten { carbohydrate counting }
What are some of the advantages of basal bolus regimens over biphasic?
More flexibility
Better control
What are some of the advantages of biphasic regimens over basal bolus?
Fewer injections needed: only twice a day
More convenient for patient
Children wouldn’t need to inject as school
Although this last point is good, current guidance recommends children are put of basal bolus rather than biphasic, as it offers tighter control and gets children into go habits
If patients are carbohydrate counting (part of basal bolus), how should they dose their insulin?
1 unit of insulin for every 10g of carbohydrate
When starting a patient on insulin, how should it be intiated?
Start on a low dose Regularly monitor their blood glucose Adjust dose by 2 units every 2-3 days Make one adjustment at a time Then once patients on 40 units plus, you can adjust by 10% to get optimal control
How much can absorption vary by at an injection site?
10-90%
What length needles should usually be used?
4mm or 5mm
This is to avoid intramuscular injection
Children definitely have 4mm
Which sites absorb insulin fastest?
Abdomen (fastest)
Arm, legs, buttocks
Insulin dosing and requirements is also dependent on body weight. What if someone looses weight?
They need to be aware that their insulin requirements will drop
What happens to insulin levels when someone’s ill?
Especially in Type 1: blood glucose levels rise during illness
There’s a special risk of hyperglycaemia
This means that people have to continue their insulin as normal even if they are not eating as sugars still high
Can lead to DKA
Climate can affect insulin. How?
You absorb insulin more readily in hot weather than cold
What is Lipodystrophy?
A result of constantly injecting in the same place
Patient may like injecting there because it is senseless and numb but they won’t get the right amount of insulin!!
What is an insulin pump?
Administers insulin through a catheter in the abdomen
Helps control BG level so motivates people
Can do an pancreas transplant
Requires anti rejection medication
Number of patients had it and now are insulin dependent
What do once daily regimens consist of?
Just inject a LONG acting insulin once, at the same time each day
Examples: insulated, glargine, Levemir
Remember prolonged duration of zinc suspension insulin can cause Hypoglyceamia
What is DKA?
Severe lack of insulin results in a consistently high blood glucose level.. But glucose can’t be used for energy
So body starts breaking down body tissues as an alternative energy source
The by product is ketones
Patient will be vomiting and dehydrated
Why is basal bolus regimen seen as more flexible?
basal bolus gives you flexibility to delay a meal as it takes away the pre-determined hypo moments that can result from not eating
Basal bolus and carbohydrate counting come hand in hand
How can we avoid night Hypos?
Decrease insulin before going to bed, not increase it!
With carbohydrate counting, what do we do?
Adjust dose of insulin around what we eat
So we don’t have to do it the other way round and watch what we eat in relation to how much insulin we’ve had
The other factor introduced in carbohydrate counting is the correction dose of insulin: things can send blood sugar up, we need to check BG, then give a dose of insulin to correct it.
You have to record everything you eat plus blood sugar levels in a diary
When doing carbohydrate counting, if the patient has a salad for lunch, how much insulin do they need?
They don’t need any
No carbohydrates in salad!
It’s all about adjusting your insulin dose according to how many carbohydrates you eat
What level of ketones trigger patient to seek urgent help??
People have keto sticks to measure ketones
Measure ketones in millimole / ml
anything above 1.5 millimole / ml seek urgent help
Dehydration is a big risk in diabetics. If they’re vomiting when should they seek help?
Dehydration is extremely fast if blood glucose is high (e.g. 40)
Can result in death
If you vomit more than 3 times then seek help
Metformin is cautioned in patients with renal disease (therefore cautioned in elderly as these tend to have deteriorating renal function) but it is said Metformin isn’t been prescribed enough due to this caution label. What are the cut offs with Metformin in renal disease?
Review if eGFR is less than 45.
Don’t use if eGFR is less than 30
If renal function isn’t good then consider a gliclazide
What is the target BP in type 2 diabetes??
Under 130/80 for people with kidney, eye or CV damage
For all others the target BP is 140/80
What is Hyperosmolar hyperglycemic state?
A life-threatening condition seen in T2 diabetes (DKA seen in type 1)
Blood glucose becomes extremely high (Plasma glucose level of 600 mg/dL or greater)
Most patients present with severe dehydration
Some of it’s features overlap with DKA. It can cause Coma.
It usually occurs in T2 diabetics when they have some other illness causing severe dehydration such as an infection.
What rate if IV infusion do we usually give to patients with DKA?
6 units of insulin per hour
Monitor capillary blood glucose every hour!!
Or measure Blood glucose when they come into hospital and use the insulin infusion sliding scale
How many litres of fluid do we give to restore dehydration in DKA?
6-8 L (usually saline/ NaCl)
If someone is conscious and has a hypo what should we give them?
10-15 g of glucose
(55ml of lucozade contains 10g)
If unconscious they are brought into hospital and given IV glucose or injected glucagon
What are the pre-prandial (before meal) and post-prandial (after meal) target glucose levels in diabetics?
Pre prandial : 4- 8 mmol/mol
Post prandial: aim for under 10 mmol/mol
What does ACR levels indicate in diabetics? What does a values of over 2.5 in men say?
Albumin creatinine ratio
Over 2.5 in men= albumin in urine= kidney damage in diabetes
Over 3.5 in women
Diabetic skin infections are more likely to be caused by _____ bacteria and therefore require _________ antibiotics such as?
More likely to be caused by anaerobic bacteria
So they require broad spectrum antibiotics such as coamoxiclav
We tend to use an insulin sliding scale in hospital when patients blood glucose is over ___? If it’s not over this what do we use to control BG?
Over 13
If not use act-rapid doses to get BG normal.
What antihypertensives are recommended in type 1 diabetics with nephropathy (some renal impairment)?
Ace inhibitors
As they can be renal protective and prevent further deterioration
