Endocrinology Flashcards
Insulin infusion rate in children in DKA?
0.05 - 0.1 units/ kg /hr
Single best test to assess thyroid function
TSH
HbA1c threshold to diagnose diabetes
48
Desmopressin test, results in
Craniogenic DI
Nephrogenic DI
- Responds, increase urine osmolality
- opposite
Glucose % and ml/hr once BGL <14 in DKA
10 % 125ml/hr
Fluid resus in adults with DKA
500ml NaCl initially over 10-15 mins
+ another 500ml if BP <90
Then 1L NaCl over 90 mins
Initial immediate treatment for a thyroid storm
beta blockers
Osmolality formula
2Na + glucose + urea
DKA CRITERIA
Glucose >11 or known diabetes
Ketones - >3 serum or 2+ on urine dip
Bicarb <15 and or pH <7.3
Complications of HSS
Re-hydrating too quickly
Cerebral oedema
Pulmonary oedema
cental pontine myelionsis
Congenital adrenal hypoplasia, deficiency in what?
deficiency of the enzyme 21-hydroxylase.
Test for congenital adrenal hypoplasia
ACTH stimulation test
HHS and advice regarding VTE
The risk of thromboembolism is very high in patients with HHS, and low molecular weight heparin should be routinely given. In patients such as this with a serum osmolality greater than 350 mmol/l full heparinisation should be considered.
Diabetic amyotrophy
(Proximal diabetic neuropathy)
second most common type of diabetic neuropathy
initially presents with pain in the buttocks, hips or thighs and is frequently unilateral initially.
Weakness and wasting of the proximal muscles of the lower limbs follow, and it can result in the patient being unable to go from sitting to standing without assistance.
Reflexes can also be affected in the corresponding areas involved. Diabetic amyotrophy is reversible with good glycaemic control, physiotherapy and lifestyle measures.
Nelson’s syndrome
Nelson’s syndrome is a rare condition that occurs many years after a bilateral adrenalectomy for Cushing’s syndrome. It is thought that it develops due to the loss of the negative feedback control that usually suppresses high cortisol levels. This, in turn, results in the re-establishment of CRH production by the hypothalamus, which subsequently stimulates the growth of an adrenocorticotrophic hormone (ACTH) producing pituitary adenoma.
Biochemical features of Addison’s disease
The classical biochemical features of Addison’s disease are as follows:
Increased ACTH levels
Elevated serum renin level
Hyponatraemia
Hyperkalaemia
Hypercalcaemia
Hypoglycaemia
Metabolic acidosis
Type A vs B lactic acidosis
Type-B lactic acidosis is defined as not having to do with tissue hypoxia or hypoperfusion.
Cushing’s disease vs Cushing’s syndrome
Cushing’s disease - an adenoma of the pituitary gland that secretes large amounts of ACTH and in turn elevates cortisol levels.
Metabolic acidosis
(with raised anion gap) causes:
(4)
Lactic acidosis (e.g. hypoxaemia, shock, sepsis, infarction)
Ketoacidosis (e.g. diabetes, starvation, alcohol excess)
Renal failure
Poisoning (e.g. late stages of aspirin overdose, methanol, ethylene glycol)
Metabolic acidosis
(with normal anion gap) causes:
(4)
Renal tubular acidosis
Diarrhoea
Ammonium chloride ingestion
Adrenal insufficiency
Metabolic alkalosis causes:
(4)
Vomiting
Potassium depletion (e.g. diuretic usage)
Cushing’s syndrome
Conn’s syndrome
Respiratory acidosis causes:
(5)
COPD
Life-threatening asthma
Pulmonary oedema
Sedative drug overdose (e.g. opiates, benzodiazepines)
Neuromuscular disease
Obesity
Respiratory alkalosis cause:
(6)
Hyperventilation (e.g. anxiety)
Pulmonary embolism
CNS disorders (e.g. CVA, SAH, encephalitis)
Altitude
Pregnancy
Early stages of aspirin overdose
How often is hydrocortisone given in adrenal crisis?
100mg IV 6hrly until the patient is haemodynamically stable and clinical improvement (alternative 200mg/24hrs by continuous IV infusion).
Glucose concentration criteria in diabetes
Random > 11
Fasting > or equal to 7
OGTT > 11
(if asymptomatic, must be on two separate occasions)
HBA1C criteria in diabetes
> or equal to 48 (confirmed with a second sample)
Parameters for diagnosis of HHS
Glucose >30
Osmolality > 320
Hypovolaemia
Absence of significant ketonaemia (<3) and acidosis (pH 7.3 / Bicarb <15)
Hyponatraemia with neurological sx
At what rate should Na be increased by
1-2 mmol/L/hr until symptoms resolve
Markers for 5% dehydration for children in DKA
ph < 7.3 / Bicarb <15
Markers for 7% dehydration for children in DKA
pH <7.2 or serum bicarbonate <10mmol/L
Markers for 10% dehydration for children in DKA
pH <7.1 or serum bicarbonate <5mmol/L
Fluid bolus in children in DKA who are shocked
20ml/kg of 0.9% (normal) saline over 15 minutes
If required, further 10ml/kg boluses up to a maximum of 40ml/kg at which point inotropes should be considered
Fluid bolus in children in DKA who are NOT shocked
10ml/kg bolus of 0.9% (normal) saline over 60 minutes
Boluses for non-shocked patients should be subtracted from the fluid deficit
Calculate fluid deficit in children with DKA
Given over what time period
Deficit (ml) = % dehydration X weight (kg) X 10
48hrs
Calculate insulin rate in DKA in children
0.05 units/kg/hour
Diabetic amyotrophy
proximal diabetic neuropathy, is the second most common type of diabetic neuropathy.
Treatment for myxoedema
Thyroid hormones
Glucocorticoids
Treat infection if present
When should insulin be stopped in DKA?
Ketones <0.6
pH >7.3 / Bicarb >18
