Disorders of clotting can present with an increased tendency to clotting (thrombophilia) or a decreased ability to form clots and therefore an increased risk of bleeding. Causes Increased clotting Congenital ● Factor V Leiden deficiency ● Protein C deficiency ●…
Anaemia is defined as a haemoglobin concentration of <13.5 g/dL in men and <11.5 g/dL in women. Classification of anaemia according to red cell indices is useful because specific investigations can be tailored accordingly. Causes Microcytic (MCV <80 fL) ●…
Blood urea is a useful test of renal function. However, other factors such as liver failure, dehydration and protein breakdown may alter levels of blood urea. The normal level of blood urea is 2.5–7.8 mmol However, values may be lower…
Respiratory alkalosis is a common disorder in critically ill patients. It occurs when carbon dioxide is lost via excessive pulmonary ventilation (↑ pH, ↓ p CO 2 ). Compensatory mechanisms are: ■ ↓ HCO 3 − by bicarbonate buffer system…
Respiratory acidosis is caused by CO 2 retention due to inadequate pulmonary ventilation (↓ pH, ↑ pCO 2 ). Compensatory mechanisms are: ■ ↑ HCO 3 − by bicarbonate buffer system ■ ↓ H + by kidneys (can take several…
Metabolic alkalosis is caused by an increase in HCO 3 − or decrease in H + (↑ pH,↑HCO 3 − ). Compensatory mechanisms are: ■ ↑ pCO 2 by hypoventilation (limited by hypoxia) ■ ↓ HCO 3 − by kidneys.…
Metabolic acidosis is caused by increased production of hydrogen ions from metabolic causes or from excessive bicarbonate loss (pH ↓, HCO 3 − ↓). Compensatory mechanisms are: ■ ↓ pCO 2 by hyperventilation ■ ↓ H + by kidneys (unless…
The normal range of serum magnesium is 0.7–1.0 mmol Hypomagnesaemia refers to a serum level below 0.7 mmol Causes You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are…
Hypocalcaemia is a serum calcium of <2.1 mmol/L (normal range 2.1–2.6 mmol/L) with an ionised fraction <0.8 mmol Causes Associated with high serum phosphate ● Chronic renal failure ● Hypoparathyroidism ● Rhabdomyolysis ● Phosphate therapy You’re Reading a Preview Become a…
Hypercalcaemia is a serum calcium >2.62 mmol/L (normal range 2.1–2.6 mmol/L). It may be an asymptomatic laboratory finding. Symptoms usually become apparent with levels >3.50 mmol Causes ● Malignancy ■ Solid tumour with lytic bony metastases, e.g. Ca breast, bronchus…