Endocrinology Flashcards
(19 cards)
What is the diagnostic criteria for a DKA?
Key points
* glucose > 11 mmol/l or known diabetes mellitus
* pH < 7.3
* bicarbonate < 15 mmol/l
* ketones > 3 mmol/l or urine ketones ++ on dipstick
What is the immediate management (0-60min) of a DKA?
- Commence 0.9% sodium chloride solution (use large bore cannula) via infusion pump.
- Systolic BP on admission 90 mmHg and over
- Give 1000ml 0.9% sodium chloride over first 60 minutes
* Systolic BP (SBP) below 90mmHg - Give 500ml of 0.9% sodium chloride solution over 10-15 minutes. If SBP remains below 90mmHg repeat whilst requesting senior input. Most patients require between 500 to 1000ml given rapidly.
- Consider involving the ITU/critical care team.
- Once SBP above 90mmHg give 1000ml 0.9% sodium chloride over next 60 minutes.
2.Commence a fixed rate intravenous insulin infusion . (0.1unit/kg/hr based on estimate of weight) 50 units human soluble insulin (Actrapid® or Humulin S®) made up to 50ml with 0.9% sodium chloride solution. If patient normally takes long acting insulin analogue (Lantus®, Levemir®) continue at usual dose and time
3.Assess patient
* Respiratory rate; temperature; blood pressure; pulse; oxygen saturation
* GCS
* Full clinical examination
4.Further Ix
* Capillary glucose
* VBG
* U&E
* FBC
* Blood cultures
* ECG
* CXR
* MSU
5.Establish monitoring requirements
* Hourly capillary blood glucose
* Hourly capillary ketones
* Venous bicarbonate and potassium at 60 minutes, 2 hours and 2 hourly thereafter.
* 4 hourly plasma electrolytes
* Continuous cardiac monitoring
* Continious pulse oximetry if required.
6.Consider and precipitating causes and treat appropriately
What are the aims of tx in DKA (60 min to 6 hrs) and how should we manage at this point?
Aims:
* Rate of fall of ketones of at least 0.5 mmol/L/hr OR bicarbonate rise 3 mmol/L/hr and blood glucose fall 3 mmol/L/hr
* Maintain serum potassium in normal range
* Avoid hypoglycaemia
- Keep monitoring
* Hourly capillary blood glucose
* Hourly capillary ketones
* Venous bicarbonate and potassium at 60 minutes, 2 hours and 2 hourly thereafter.
* If potassium is outside normal range, re-assess potassium replacement and check hourly. If abnormal after further hour seek immediate senior medical advice
2.Continue fluid replacement via infusion pump
* 0.9% sodium chloride 1L with potassium chloride over next 2 hours
* 0.9% sodium chloride 1L with potassium chloride over next 2 hours
* 0.9% sodium chloride 1L with potassium chloride over next 4 hours
* Add 10% glucose 125ml/hr if blood glucose falls below 14 momol/L
3.Assess response to treatment
* Review infusion rate if aims not required.
* Continue fixed rate IVII until ketones less than 0.3 mmol/L, venous pH over 7.3 and/or venous bicarbonate over 18 mmol/L.
Additional measures …
What are the aims of tx in DKA (6 hrs to 12 hrs) and how should we manage at this point?
Aims: Improvement + Assess for complications
1. Reassess + monitor
*0.9% sodium chloride 1L with potassium chloride over next 4 hours
0.9% sodium chloride 1L with potassium chloride over next 6 hours
2.Check for fluid overload
3.Review biochemical markers
* At 6 hours check venous pH, bicarbonate, potassium, capillary ketones and glucose
* Resolution is defined as ketones less than 0.3 mmol/L, venous pH over 7.3 (do not use bicarbonate as a surrogate at this stage).
* Ensure referral has been made to diabetes team
What are the aims of tx in DKA (12 hrs to 24 hrs) and how should we manage at this point?
By 24 hours the ketonaemia and acidosis should have resolved. Request senior review if not improving
1. Re-assess patient, monitor vital signs
2.Review biochemical and metabolic parameters
* At 12 hours check venous pH, bicarbonate, potassium, capillary ketones
* Resolution is defined as ketones <0.3 mmol/L, venous pH>7.3
What should be done after the resolutions of a DKA?
When should a central line or HDU be considered?
What potassium replacements should be given in DKA?
What are the complications of a DKA?
- gastric stasis
- thromboembolism
- arrhythmias secondary to hyperkalaemia/iatrogenic hypokalaemia
- iatrogenic due to incorrect fluid therapy: cerebral oedema*, hypokalaemia, hypoglycaemia
- acute respiratory distress syndrome
- acute kidney injury
How is T2DM diagnosed?
If the patient is symptomatic:
* fasting glucose greater than or equal to 7.0 mmol/l
* random glucose greater than or equal to 11.1 mmol/l (or after 75g oral glucose tolerance test)
If the patient is asymptomatic the above criteria apply but must be demonstrated on two separate occasions.
HbA1c -
- a HbA1c of greater than or equal to 48 mmol/mol (6.5%) is diagnostic of diabetes mellitus
- a HbA1c value of less than 48 mmol/mol (6.5%) does not exclude diabetes (i.e. it is not as sensitive as fasting samples for detecting diabetes)
- in patients without symptoms, the test must be repeated to confirm the diagnosis
When can HbA1c not be used to diagnose DM?
- haemoglobinopathies
- haemolytic anaemia
- untreated iron deficiency anaemia
- suspected gestational diabetes
- children
- HIV
- chronic kidney disease
- people taking medication that may cause hyperglycaemia (for example corticosteroids)
What dietary advice should be given for T2DM?
- encourage high fibre, low glycaemic index sources of carbohydrates
- include low-fat dairy products and oily fish
- control the intake of foods containing saturated fats and trans fatty acids
- limited substitution of sucrose-containing foods for other carbohydrates is allowable, but care should be taken to avoid excess energy intake
- discourage the use of foods marketed specifically at people with diabetes
- initial target weight loss in an overweight person is 5-10%
What are appropriate HbA1c targets for T2DM patients?
A case-by-case basis, with particular consideration for people who are older or frail, for adults with type 2 diabetes
If patient is already on one drug but HbA1c had rised to 58 mmol/mol (7.5%) -> HbA1c target = 53mmol/mol (7.0%)
What is the first line management of T2DM?
Metformin remains the first-line drug of choice in type 2 diabetes mellitus.
* metformin should be titrated up slowly to minimise the possibility of gastrointestinal upset
* if standard-release metformin is not tolerated then modified-release metformin should be trialled
SGLT-2 inhibitors
should also be given in addition to metformin if any of the following apply:
* the patient has a high risk of developing cardiovascular disease (CVD, e.g. QRISK ≥ 10%)
* the patient has established CVD
* the patient has chronic heart failure
metformin should be established and titrated up before introducing the SGLT-2 inhibitor
SGLT-2 inhibitors should also be started at any point if a patient develops CVD (e.g. is diagnosed with ischaemic heart disease), a QRISK ≥ 10% or chronic heart failure
What is the most common cause of primary hyperaldosteronism?
idiopathic adrenal hyperplasia is the cause in up to 70% of cases
What is the some other causes of primary hyperaldosteronism?
- an adrenal adenoma
- Adrenal carcinoma
What are the features of primary hyperaldosteronism?
- hypertension
- hypokalaemia
- e.g. muscle weakness
- this is a classical feature in exams but studies suggest this is seen in only 10-40% of patients
- alkalosis
How should primary hyperaldosteronism be investigated?
- plasma aldosterone/renin ratio is the first-line investigation - should show high aldosterone levels alongside low renin levels (negative feedback due to sodium retention from aldosterone)
*following this a high-resolution CT abdomen and adrenal vein sampling is used to differentiate between unilateral and bilateral sources of aldosterone excess.
If the CT is normal adrenal venous sampling (AVS) can be used to distinguish between unilateral adenoma and bilateral hyperplasia
How should primary hyperaldosteronism be managed?
- adrenal adenoma: surgery
- bilateral adrenocortical hyperplasia: aldosterone antagonist e.g. spironolactone
