insulin Flashcards
drivers who are treated with insulin should always carry the following when driving, even if they use a continuous glucose monitoring system
capillary blood glucose meter
test strips
drivers who use a continuous glucose monitoring system who experience hypo symptoms or have a CGM reading of 4mmol/litre or below should confirm their BGC with….
capillary blood reading
when do blood glucose levels need to be checked before and during driving?
no more than 2 hours before
every 2 hours while driving
when may more frequent self monitoring be required for insulin users who are driving (normally needs to be no more than 2 hours before, and every 2 hours whilst driving)
if for any reason there is a greater risk of hypo e.g. after physical activity or altered meal routine
what does BG conc need to be whilst driving, and what should you do it if is less than this
needs to be at least 5 mmol/litre while driving
if between 4-5 take a snack
if below 4, treat hypo
what do all drivers taking insulin need to ensure is always available in the vehicle
fast acting carb
Glucose tablets, glucose drinks, full-sugar soft drinks or squashes, jellies (not diet), sweets
do not drive if….
BG 4 or below, or warning signs of hypo
what to do if you are driving and BG levels drop to 4 below or there are warning signs of hypo
stop vehicle in safe place ASAP and turn off engine
remove keys from ignition and move from drivers seat
wait until 45 mins after BG has returned to at least 5 before continuing journey
how long do you need to wait to drive after BG levels have returned to at least 5 to drive after warning signs of hypo developing/BG dropping to 4 or below?
45 mins
who needs to inform DVLA of their condition and needs to monitor BG levels before and during driving
- insulin
- may be necessary for some other oral anti diabetic drugs that hold risk of hypo e.g. meglitinides, SU
if the patient has lost hypoglycaemia awareness, but they are using CGM system and have capillary blood glucose monitor and test strips, are they allowed to drive
NO - cannot drive if hypoglycaemia awareness is lost! must inform DVLA. can resume if medical report confirmed awareness regained
group 1 drivers who have had more than one episode of severe hypoglycaemia while awake in the last 12 months
Must not drive and must notify DVLA
Group 2 drivers after every episode of severe hypoglycaemia in the last 12 months
Must not drive and must notify DVLA following all episodes of severe hypoglycaemia.
hypoglycaemia unawareness for group 2 drivers - DVLA guidance
Must not drive and must notify DVLA
The licence will be refused or revoked
will a group 1 drive have their licensed revokes if they have hypoglycaemia unawareness
no but they must not drive and must notify DVLA. driving may resume after clinical report by GP or consultant diabetes specialist confirms it has been regained
will a group 2 driver have their licensed revoked if they have hypoglycaemia unawareness
yes
DVLA advice for group 1 drivers who have temporary insulin treatment – including gestational diabetes or post-myocardial infarction
can drive and don’t need to notify DVLA as long as under medical supervision, and not advised by clinical as at risk of diabsliqng hypoglycaemia
- may drive but have to notify DVLA if disabling hypo occurs, or if treatment continues for >3 moths, or in gestation diabetes if treatment continues for 3 months after delivery
a patient is on insulin therapy for gestational diabetes. can she still drive and does she need to inform DVLA
can drive. doesn’t need to notify DVLA as long as she is under medical supervision and is not at risk of disabling hypoglycaemia.
can drive but does need to notify DVLA if disabling hypo occurs, or if treatment continues for 3 months after delivery
what is severe hypoglycaemia?
episode of hypo that requires assistance of another person
a maximum of …… should pass between pre-diving glucose test and first glucose test performed after driving started
2 hours
Natural profile of insulin secretion in the body:
Basal insulin (low and steady secretion of background insulin that controls glucose continuously released from liver
Meal time bolus insulin (secreted in response to glucose absorbed from food and drink)
3 types of insulin available in UK
Human insulin
Human insulin analogues
Animal insulin
Human insulin and insulin analogues are ….. immunogenic than animal insulins
less
What makes human insulin analogues different to human insulin?
Both produced by recombinant DNA tech
Both have same amino acid sequence as endogenous insulin
Analogues: modified to produce desired kinetic characteristics e.g. extended duration of action or faster absorption and onset of action
why can’t insulin be given PO
Inactivated by GI enzymes - must be given by injection, SC ideal in most circumstances
where does insulin need to be injected
Inject into a part of the body with plenty of SC fat
Abdomen - fastest absorption rate
Outer thighs, buttocks - slower absorption compared to abdomen or inner thighs
what body part has the fastest absorption rate when injecting insulin
Abdomen
is absorption at limb site injected the same
no.
absorption from limb site can vary (by as much as 20-40%) day to day, esp in children
what factors can affect rate of insulin absorption after injection
Local tissue reactions, changes in insulin sensitivity, injection site, blood flow, depth of injection and the amount of insulin injected
how can exercise increase insulin absorption
Increased blood flow around injection site due to exercise can also increase insulin absorption
what is lipohypertrophy
lump of fatty tissue under your skin caused by repeated injections in the same place
what to advice pt regarding lipohypertrophy
May occur due to repeated injection into the same small area
Can cause erratic absorption of insulin
Can contribute to poor glycaemic control
Advice pt not to use affected areas for further injection until skin has recovered
Can be minimised by using diff injection sites in rotation
check infection sites for the following before administration
Signs of infection
Swelling
Bruising
Lipohypertrophy
Insulin preparations can be broadly categorised into 3 groups based on their time-action profiles
SA insulin, including soluble and RA acting
Intermediate acting insulins
LA insulins
short acting insulin - characteristics
Short duration
Relatively rapid onset of action, to replicate insulin normally produced in response to glucose absorbed from a meal
short acting insulin’s are available as….
soluble insulin (human, borvine or porcine) and RA insulin analogues (GAL: glulisine, aspart, lispro)
remember rapid acting insulins as rapid LAG
lispro
aspart
glulisine
soluble insulin is usually given …. but some preps can be given….
SC but some preps given IV and IM
soluble insulin is usually injected ….. mins before meals depending on prep used
15-30 mins
characteristics of soluble insulin when injected SC
- rapid onset of action (30-60mins)
- peak action between 1-4 hours
- duration of action up to 9 hours
characteristics of soluble insulin when injected IV
- short half life of only a few mins
- onset of action is instantenous
- most appropriate form of insulin for use in emergencies e.g. DKA and peri-operatively
which insulin is most appropriate for use in diabetic emergencies e.g. DKA and peri operatively and why
soluble insulin injected IV as it has instant onset of action
RA insulin (Lispro, aspart, glulisine) is usually injected …
SC
RA insulin (Lispro, aspart, glulisine) characteristics compared to soluble insulin
- faster onset of action (within 15 mins) and shorter duration of action (2-5hours) than soluble insulin
- soluble acts within 30-60 mins and peaks at 1-4 hours and acts for up to 9 hours
if you are using RA insulin (lispro, aspart, glulisine) as part of maintenance regimen, when should you inject
ideally immediately before meals
routine use of post meal injections should be avoided as this is associated with poorer glucose control, increased risk of high postprandial glucose conc and subsequent hypo
brands of RA insulin (lispro, aspart, glulisine)
lispro: Humalog kwikpen, lyumjev
aspart: fiasp, novorapid
glulisine: apidra
what is intermediate acting insulin called
insulin isophane
brands of insulin isophane
(humulin I, hypurin porcine, insulatard)
characteristics of intermediate acting insulin
Have intermediate duration of action, designed to mimic effect of endogenous basal insulin
When given SC, onset of action ~1-2 hours, maximal effect at 3-13 hours and duration of action of 11-24 hours
what is isophane insulin
- suspension of insulin with protamine
- intermediate acting
how can isophane insulin be given as a regimen
- intermediate duration of action
- can be given as one or more daily injections, along separate meal time SA insulin injections
- can also be mixed with a SA (soluble or RA) insulin in the same syringe
- this can be mixed by the pt or you can get pre mixed biphasic insulin
give examples of pre mixed biphasic insulin
biphasic isophane insulin, biphasic insulin aspart, biphasic insulin lispro
do all biphasic insulin pre mixed preparations contain the same % of SA insulin
no it varies form 15-50%
when to administer pre mixed biphasic insulin preparations
SC immediately before meals
what are the 5 long acting insulins
protamine zinc insulin
insulin zinc suspension
insulin detemir
insulin glargine
insulin degludec
how to remember LA insulins: DDG
degludec
detemir
glargine
how to long acting insulin’s work and how long is their duration of action
Like intermediate acting insulins, the LA insulins mimic endogenous basal insulin secretion but their duration of action may last up to 36 hours
They achieve steady state level after 2-4 days to produce a constant level of insulin
how often are doses of the LA insulins given
Insulin glargine and insulin degludec are given OD
Insulin detemir is given OD or BD according to individual requirements
MHRA insulins: risk of severe harm and death due to withdrawing insulin from pen devices
Insulin should not be extracted from insulin pen devices. The strength of insulin in pen devices can vary by multiples of 100 units/mL. If insulin extracted from a pen or cartridge is of a higher strength, and that is not considered in determining the volume required, it can lead to a significant and potentially fatal overdose.
What is the insulin NHS Never Event - MHRA
Overdose of insulin due to abbreviations or incorrect device. The words ‘unit’ or ‘international units’ should not be abbreviated.
Specific insulin administration devices should always be used to measure insulin i.e. insulin syringes and pens.
Insulin should not be withdrawn from an insulin pen or pen refill and then administered using a syringe and needle.
MHRA - all types of insulin - risk of cutaneous amyloidosis at injection site
- injection of all types can lead to deposits of amyloid protein under the skin at the injection site
- this interferes with insulin absorption and thus can affect glycaemic control
- consider cutaneous amyloidosis as a differential diagnosis to lipodystrophy when pt present with SC lymph at injection sites
- ensure pt rotate injection sites
- ensure pt know that injecting into these lumpy areas can reduce effectiveness of insulin
Patients currently injecting into ‘lumpy’ (amyloidosis or lipodystrophy) areas should contact their GP before chaining injection site due to..
risk of hypo
BGC should be closely monitored after changing injection site and dose adjustment of insulin or other antidiabetics may be needed
which abx has a severe interaction with insulin because it has been reported to cause hypo when given with insulin, and therefore BG must be monitored?
clarithromycin
use of insulin during pregnancy
insulin requirements may alter and doses should be assessed frequently by an experienced diabetes physician.
dose of insulin generally needs to be increased in the second and third trimesters
in which trimesters of pregnancy does the dose of insulin generally need increasing
2 and 3
use of insulin in breastfeeding pt
insulin requirements may alter and doses should be assessed frequently by an experienced diabetes physician
which acting injectable insulin can be given by continuous SC infusion using portable infusion pump?
short acting.
ideal storage temperature for insulin that is not in use
2-6 degrees
storage for insulin that has been opened and is in use
room temperature
can you store insulin in freezer
never
a patient comes in and asks if the insulin they have is safe to use because it has been kept out of the fridge for 28 days.
throw away insulin if it has been kept out of fridge for 28 days or more
