Clin Chem Flashcards
1
Q
What arethe causes of hypovolaemic hyponatraemia?
A
- Urine sodium >20mM (renal loss)
- Diuretics
- Addisons
- Osmolar diuresis (glucose)
- Renal failure (diuretic phase)
- Urine sodium <20mM (extrarenal loss)
- Diarrhoea
- Vomiting
- Fistula
- SBO
- Burns
2
Q
What are the causes of hypervolaemic hyponatraemia?
A
- Cardiac failure
- Nephrotic syndrome
- Cirrhosis
- Renal failure
3
Q
What are the causes of euvolaemic hyponatraemia?
A
- Urine osmolality >500
- SIADH
- Urine osmolality <500
- Water overload
- Severe hypothyroidism
- Glucocorticoid insufficiency
4
Q
What are the ECG features of hypokalaemia?
A
- Flattened/inverted T waves
- Prominent U waves (after T waves)
- ST depression
- Long PR interval
- Long QT interval
5
Q
What are the ECG features of hyperkalaemia?
A
- Tall tented T waves
- Flattened P waves
- Increased PR interval
- Widened QRS
- Sine wave pattern -> VF
6
Q
Which drugs cause hyperkalaemia?
A
potassium sparing diuretics, ACE inhibitors, angiotensin 2 receptor blockers, spironolactone, ciclosporin, heparin
7
Q
Formula for anion gap
A
([Na+] + [K+]) - ([Cl] + [HCO3])
8
Q
Which conditions have high cholesterol rather than high triglycerides?
A
nephrotic syndrome, cholestasis, hypothyroidism
