Data interpretation Flashcards
Cause of microcytic anaemia.
Shown by low MCV – Iron deficiency.
Causes of normocytic anaemia.
Anaemia of chronic disease.
Acute blood loss.
Causes of macrocytic anaemia.
B12/folate deficiency.
Alcohol excess.
Liver disease.
Causes of thrombocytopenia.
Reduced production – infection, drugs, myelodysplasia.
Increased destruction – heparin, hypersplenism, DIC
Causes of thrombocytosis.
Reactive – bleeding, tissue damage, post-splenectomy.
Primary – myeloproliferative disorders.
Causes of hyponatraemia.
Hypovolaemic – fluid loss, Addison’s disease, diuretics.
Euvolaemic – SIADH, psychogenic polydipsia, hypothyroid.
Hypervolaemic – heart/renal/liver/nutritional/thyroid failure.
Causes of hypernatraemia.
Dehydration, drips, drugs, diabetes insipidus (opposite of SIADH).
Causes of hypokalaemia.
DIRE: Drugs (loop and thiazide diuretics). Inadequate intake. Renal tubular acidosis. Endocrine (Cushing's and Conn's syndromes).
Causes of hyperkalaemia.
DREAD: Drugs (K+ sparing diuretics, ACEi) Renal failure. Endocrine (Addison's). Artefact (clotted sample) DKA (after giving insulin K+ will drop).
Differentiating types of AKI.
Pre-renal: urea rise»creatinine rise.
Renal: urea rise «_space;creatinine rise.
Post-renal: urea rise «_space;creatinine rise and bladder/hydronephrosis may be palpable.
What can a raised urea indicate?
Kidney injury or upper GI bleed (the break down of blood releases urea into the stomach and it is absorbed into the blood stream). If a patient has a raised urea but a normal creatinine, investigate their haemoglobin.
How to identify hepatocyte injury.
Bilirubin.
ALT AST.
Alkaline phosphate.
How to identify liver function changes.
Albumin.
Vitamin K dependent clotting factors (II, VII, IX, X) – PT and INR.
Differentiating between pre-hepatic, hepatic and post-hepatic liver problems.
Pre-hepatic: raised bilirubin only.
Hepatic: raised bilirubin and AST/ALT.
Post-hepatic: raised bilirubin and ALP.
Causes of raised bilirubin only.
PRE-HEPATIC PROBLEMS.
Haemolysis – red blood cell break down.
Causes of raised bilirubin and AST/ALT.
HEPATIC PROBLEMS. Fatty liver. Hepatitis. Cirrhosis. Malignancy. Metabolic: Wilson’s disease. Heart failure.
Causes of raised bilirubin and ALP.
POST-HEPATIC PROBLEMS.
Lumen: stones, drugs causing cholestasis.
In wall: tumour, PBC, sclerosing cholangitis.
Extrinsic pressure: pancreatic/gastric cancer, lymph node.
When a patient is taking levothyroxine, what range of TSH concentration are you aiming for?
0.5-5mlU/L
Always change the dose by the smallest increment.
Decreased T4 and raised TSH.
Primary hypothyroidism – Hashimoto’s thyroiditis, drug-induced hypothyroidism.
Decreased T4 and decreased TSH.
Secondary hypothyroidism – due to pituitary tumour/damage.
Increased T4 and decreased TSH.
Primary hyperthyroidism – Grave’s disease and toxic nodular goitre.
Increased T4 and increased TSH.
Secondary hyperthyroidism – pituitary tumour.
Signs of pleural effusion on chest x-ray.
Alveolar oedema (bat wings). kerley B lines. Cardiomegaly. Diversion of blood to the upper lobes. pleural Effusion.
Normal ABG ranges.
pH 7.35-7.45 PaCO2 4.7-6.0kPa PaO2 11-13kPa HCO3- 22-26 Base excess -2 to +2