5: Diabetes & Steroids Management Flashcards
which diabetes medications cause a fall in blood glucose
- insulins
- sulphonylureas
- meglitinides
- SGLT-2 inhibitors
which diabetes medications cause a glucose dependent fall in blood glucose
- pioglitazone
- DPP-4 inhibitors
- GLP-1 analogues
which diabetes medications prevent a rise in blood glucose
- metformin
- acarbose
what are the onsets and lengths of action of insulins
basal bolus regime
twice daily pre-mixed regime
what are the risks of surgery in patients with diabetes
- ↑ risk of morbidity and mortality
- infections, wounds
- underlying diabetic compliactions mainly CVS, AMI, stroke, ARF
- errors of blood glucose management
what are the benefits of good glucose control prior to surgery
- fewer complications
- fewer patients need an insulin infusion
- more patients have day surgery
what should you aim for the HbA1c to be prior to surgery
~ 69mmol/mol^-1
what happens if the Hba1c is >69 mmol/mol before surgery
- if urgent: plan peri-op VRIII
- otherwise consider delay and optimise
what happens if the Hba1c is <69 mmol/mol before surgery
- proceed to admission
- adjust insulin/non-insulin meds
- plan VRIII if necessaey
how is diabetes managed intra-operatively
- check CBG at induction and then hourly
- aim for CBG 6-12 mmol/L
- do not stop VRIII
how is diabetes managed post-operatively
continue hourly CBG
- aim CBG 4-12mmol/L - if usual treatment can cause hypoglycaemia e.g. insulin, sulphonylurea
- aim CBG 3.5-12 mmol/l - if usual treatment cannot cause hypoglycaemia e.g. metformin
- maintain glycaemic control, fluid & electrolytes
- facilitate early eating & drinking
- avoid iatrogenic injury
when do you treat hypoglycaemia
- CBG <4 mmol/L: 50-100ml 20% glucose
- CBG 4-6 if symptomatic: 50-100ml 10% glucose
- recheck CBG at 10 mins, if persistent hypoglycaemia then contact diabetes team
what is the ideal range for normoglycaemia
6-10 mmol/L
- continue hourly CBG monitoring
what is the range of hyperglycaemia and how is this managed
> 12 mmol/L, blood ketones < 3 or urine ketones < +++
- give s/c rapid analogue insulin and reassess
- may need VRIII
- check for DKA
what is VRIII
variable rate intravenous insulin infusions (sliding scale insulin)
what are risks/cautions of VRIII
- do not infuse insulin without substrate unless in ITU/HDU/CCU
- measure CBG hourly
- ensure administration of long acting basal insulin to prevent hyperglycaemia & ketosis on cessation
- do not take down VRIII in T1 diabetics until alternative s/c insulin has been given in previous 30 mins
- RDA of sodium to prevent hypoNa+
what are the parameters of diagnosis of DKA
- ketonaemia >= 3.0 mmol or significant ketonuria (more than 2+ on standard urine stick)
- blood glucose > 11.0 mmol or known DM
- bicarb < 15.0 mmol and/or venous pH < 7.3
what is the management of DKA
- measure blood ketones, venous pH and bicarb to use as treatment markers
- monitor ketones and glucose
- use weight based FRIII
- use venous not arterial blood sample
- monitor electrolytes using blood gas analyser
- give long acting, basal insulin
- give 10% glucose IV once CBG <14 - do not reduce insulin infusion till blood ketones controlled
what are the actions of cortisol
- increase availability of glcuose to facilitate fight or flight
- suppresses immune functions and inflammation
what is normal cortisol production and how does this change with surgery
- normal: 15-30mg/day pulsatile with circadian rhythm
- 50mg/day minor procedures
- 75-150mg/day moderate/major operations (up to 72 hours post cardiac surgery)
what is Cushings syndrome vs disease
excess cortisol production/glucocorticoid medications over a long period of time
- syndrome: exogenous glucocorticoids e.g. pred or adrenal/other tumour
- disease: secondary to pituitary tumour
what are features of Cushings disease
- moon face
- central obesity
- buffalo hump
- thin, easily bruised skin
- purple striae on abdomen and thighs
- prox muscle wasting
- HT, LVH, T2DM, hypoK
what increases the risk of HPA suppression
- <5mg/day prednisolone - minimal risk HPA
- > 5mg/day prednisolone for > 1 month - higher risk of HPA
how can HPA suppression be measured
- short synacthen test
- 250mcg synacthen
- measure cortisol at 0,30,60 mins
- peak at 420-700 nmol/L normal
how does adrenal/addisonian crisis present
- orthostatic hypotension
- headache, confusion, coma
- dehydration, dizziness
- abdo/flank pain
- fatigue, weakness, fever, N&V, loss of appetite
- tachycardia, high RR, CVS collapse
how is adrenal/addisonian crisis treated
hydrocortisone 100mg IV
what is ‘steroid cover’ and why is it needed
surgery creates extra physiological stress which requires a ‘stress response’
- ‘steroid cover’ replaces the natural stress response surge in cortisol production
what are the components of ‘steroid cover’
- double usual steroid for 24-48 hours
- hydrocortisone 100mg IV on induction followed by IV infusion 200mg/24 hr (or 50mg IM 6 hourly)
- or for adrenal suppression patients only dexamethasone 6-8mg IV will last 24 hrs
how is metformin intake (biguanide) modified for surgery
- day prior: take as normal
- morning operation: if taken TDS, omit lunchtime dose
- afternoon operation: ‘’ ‘’
generally, how are diabetic patients medications managed pre-surgery (3)
- pt w good glycaemic control can be managed by adjusting their usual insulin regimen
- surgery requiring fasting or more than one missed meal, poorly controlled –> VRIII
- oral drugs are manipulated on the day
how is sulphonylurea medication intake modified for surgery
- day prior: as normal
- morning op: if OD omit, if BD omit morning
- afternoon: if OD omit, if BD omit both
how are once daily insulin medications modified for surgery e.g. Lantus, Levemir
reduce dose by 20% at all stages
how are twice daily insulin medications modified for surgery e.g. Novomix 30, Humulin
- day prior: no change
- morning/afternoon: 1/2 usual morning dose and leave evening dose unchanged
