Diabetes CPC Flashcards
(32 cards)
48 yo Unconscious woman with recent Hx of vomiting, polyuria and polydipsia. Obese, dehydrated and ++++glycosuria on dip. Likely diagnosis?
HHS/ HONK coma - hypooperfusion (hypotension) causes unconsciousness
What test should we do first?
ABG
pH 7.65
PCO2 = 6.1 kPa (N 4.7-6.0)
PO2 = 15 kPa
What is the acid/ base abnormality?
Metabolic alkalosis
What are the causes of metabolic alkalosis?
H+ loss (e.g. vomiting)
Hypokalaemia
Ingestion of Bicarbonate
What is the formula for osmolality?
2(Na+K) + U + G
What are the causes of hypokalaemia?
Intestinal loss- Diarrhoea, vomiting, fistula
Renal loss- mineralocorticoid excess, diuretics, renal tubular
Redistribution- Insulin, alkalosis
Rare causes: Renal tubular acidosis type 1& 2, hypomagnesaemia
What does hypokalaemia lead to?
Alkalosis- Low K means shift of H+ into cells and causes extracellular alkalosis
What does alkalosis lead to?
Hypokalaemia- more K+ into cells instead of H+
KIDNEY
Lack of intracellular potassium leads to:
Increased excretion of H+ in exchange for sodium
The production of an acid urine
Generation of bicarbonate
KIDNEY
Lack of intracellular potassium leads to:
Increased excretion of H+ in exchange for sodium
The production of an acid urine
Generation of bicarbonate
Longstanding hypertension and diabetes
Previous fractured hip
Slowly worsening obesity.
Wound on shin that did not heal
What is the diagnosis?
Cushing’s syndrome
What are the causes of Cushing’s?
Pituitary
Ectopic ACTH
Adrenal
Dexamethasone failed to suppress
Low dose dex: cortisol = 3100 nM
High dose dex: cortisol = 2990 nM
(totally failed to suppress).
Ectopic ACTH
Why does Cushing’s cause hypokalaemia?
Because VERY high levels of cortisol bind to the aldosterone receptor.
What are the causes of Ectopic ACTH?
Lung cancer
Other cancers
Examination reduced on RIGHT
Percussion: dull on RIGHT
Vocal resonance: increased on RIGHT
Diagnosis?
Collapse and consolidation
Patient very hypotensive
Patient hypokalaemic
Osmolality : 380 mosm/kg
Management?
Rehydrate cautiously
Reduce potassium
She does not pass any urine.
Na 145 K 4.0
U 45 Creat 450.
What is the differential diagnosis ?
Acute renal failure (dehydration)
Chronic renal failure (diabetes)
BP recovers to 130 / 80
JVP starts to rise
Risk of pulmonary oedema
Remains anuric for 24 h
Na: 145, K: 5.2, U 50, creat 500, Glucose 34.0
What now?
Acute renal failure ? (ATN)
Chronic renal failure ? (diabetic renal disease)
Acute renal failure ? (ATN)
Chronic renal failure ? (diabetic renal disease)
How can we distinguish them ?
Renal Biopsy
What is the treatment of ATN and Diabetic glomerular kidney disease?
If ATN, then dialyse for 3 weeks (will recover)
Diabetic glomerular kidney disease is end stage renal failure and will need lifelong dialysis
What is this?
ATN
Ectopic ACTH adrenal
Pituitary Cushing’s Adrenal
What this?
Inferior STEMI
