Data interpretation

Question 1

Cause of microcytic anaemia.

Answer 1

Shown by low MCV – Iron deficiency.

Question 2

Causes of normocytic anaemia.

Answer 2

Anaemia of chronic disease.

Acute blood loss.

Question 3

Causes of macrocytic anaemia.

Answer 3

B12/folate deficiency.
Alcohol excess.
Liver disease.

Question 4

Causes of thrombocytopenia.

Answer 4

Reduced production – infection, drugs, myelodysplasia.

Increased destruction – heparin, hypersplenism, DIC

Question 5

Causes of thrombocytosis.

Answer 5

Reactive – bleeding, tissue damage, post-splenectomy.

Primary – myeloproliferative disorders.

Question 6

Causes of hyponatraemia.

Answer 6

Hypovolaemic – fluid loss, Addison’s disease, diuretics.
Euvolaemic – SIADH, psychogenic polydipsia, hypothyroid.
Hypervolaemic – heart/renal/liver/nutritional/thyroid failure.

Question 7

Causes of hypernatraemia.

Answer 7

Dehydration, drips, drugs, diabetes insipidus (opposite of SIADH).

Question 8

Causes of hypokalaemia.

Answer 8

DIRE:
Drugs (loop and thiazide diuretics).
Inadequate intake.
Renal tubular acidosis.
Endocrine (Cushing's and Conn's syndromes).

Question 9

Causes of hyperkalaemia.

Answer 9

DREAD:
Drugs (K+ sparing diuretics, ACEi)
Renal failure.
Endocrine (Addison's).
Artefact (clotted sample)
DKA (after giving insulin K+ will drop).

Question 10

Differentiating types of AKI.

Answer 10

Pre-renal: urea rise»creatinine rise.
Renal: urea rise &laquo_space;creatinine rise.
Post-renal: urea rise &laquo_space;creatinine rise and bladder/hydronephrosis may be palpable.

Question 11

What can a raised urea indicate?

Answer 11

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.

Question 12

How to identify hepatocyte injury.

Answer 12

Bilirubin.
ALT AST.
Alkaline phosphate.

Question 13

How to identify liver function changes.

Answer 13

Albumin.

Vitamin K dependent clotting factors (II, VII, IX, X) – PT and INR.

Question 14

Differentiating between pre-hepatic, hepatic and post-hepatic liver problems.

Answer 14

Pre-hepatic: raised bilirubin only.
Hepatic: raised bilirubin and AST/ALT.
Post-hepatic: raised bilirubin and ALP.

Question 15

Causes of raised bilirubin only.

Answer 15

PRE-HEPATIC PROBLEMS.

Haemolysis – red blood cell break down.

Question 16

Causes of raised bilirubin and AST/ALT.

Answer 16

HEPATIC PROBLEMS.
Fatty liver.
Hepatitis.
Cirrhosis.
Malignancy.
Metabolic: Wilson’s disease.
Heart failure.

Question 17

Causes of raised bilirubin and ALP.

Answer 17

POST-HEPATIC PROBLEMS.
Lumen: stones, drugs causing cholestasis.
In wall: tumour, PBC, sclerosing cholangitis.
Extrinsic pressure: pancreatic/gastric cancer, lymph node.

Question 18

When a patient is taking levothyroxine, what range of TSH concentration are you aiming for?

Answer 18

0.5-5mlU/L

Always change the dose by the smallest increment.

Question 19

Decreased T4 and raised TSH.

Answer 19

Primary hypothyroidism – Hashimoto’s thyroiditis, drug-induced hypothyroidism.

Question 20

Decreased T4 and decreased TSH.

Answer 20

Secondary hypothyroidism – due to pituitary tumour/damage.

Question 21

Increased T4 and decreased TSH.

Answer 21

Primary hyperthyroidism – Grave’s disease and toxic nodular goitre.

Question 22

Increased T4 and increased TSH.

Answer 22

Secondary hyperthyroidism – pituitary tumour.

Question 23

Signs of pleural effusion on chest x-ray.

Answer 23

Alveolar oedema (bat wings).
kerley B lines.
Cardiomegaly.
Diversion of blood to the upper lobes.
pleural Effusion.

Question 24

Normal ABG ranges.

Answer 24

pH 7.35-7.45
PaCO2 4.7-6.0kPa
PaO2 11-13kPa
HCO3- 22-26
Base excess -2 to +2

Question 25

If a patient is on high flow oxygen, what should their FiO2 be?

Answer 25

The % O2 they’re on - 10. So if they’re on 40% O2 their FiO2 should be 30.

Question 26

Levels of hypoxia.

Answer 26

O2 <10kPa = hypoxic.

O2 <8kPa = severely hypoxic, in respiratory failure.

Question 27

Blood gases in T1 RF.

Answer 27

Hypoxaemia <8kPa.

Normocapnia 4.7-6.0kPa.

Question 28

Blood gases in T2 RF.

Answer 28

Hypoxaemia <8kPa.

Hypercapnia >6.0kPa.

Question 29

Blood gases in compensated T2 RF.

Answer 29

Hypoxaemia <8kPa.
Hypercapnia >6.0kPa.
With raised HCO3.

Question 30

Cause of respiratory acidosis.

Answer 30

Slow shallow breathing (blue bloaters).

Question 31

Cause of respiratory alkalosis.

Answer 31

Rapid breathing – disease or anxiety driven.

Question 32

Causes of metabolic alkalosis.

Answer 32

Caused by vomiting, diuretics and Conn’s syndrome.

Question 33

Frequent causes of metabolic acidosis.

Answer 33

DKA, lactic acidosis, renal failure, ethanol intoxication.

Question 34

If heart rate 150 what should you consider?

Answer 34

Atrial flutter: 2:1 atrial contractions to ventricular so 150 (ventricular rate) may be 300 atrial.

Question 35

Degrees of heart block.

Answer 35

First – constant PR interval >1 big square.
Second T1 – increasing PR interval, then QRS missed.
Second T2 – 2/3 P waves for each QRS.
Third (complete) – no connection between P and QRS waves.

Question 36

Common drugs with narrow therapeutic index’s

Answer 36

Digoxin.
Phenytoin.
Lithium.
Theophylline.
Gentamicin and vancomycin.

Question 37

What do you do if a patient has a high serum-gentamicin concentration?

Answer 37

Decrease the frequency of drug by 12h.

Question 38

Management of paracetamol overdose.

Answer 38

Supportive – fluids.

Specific – N-acetyl cystine.

Question 39

Levels of warfarin over anticoagulation and how to respond.

Answer 39

INR <6 – reduce dose.
INR 6-8 – stop warfarin for 2 days then reduce dose.
INR >8 – stop warfarin, give 1-5mg oral vitamin K.

Question 40

What do you do if someone is bleeding when on warfarin?

Answer 40

– Stop warfarin.
– Give vitamin K 5-10mg IV.
– Give prothrombin complex (Beriplex).

Question 41

Target INRs in patients on warfarin.

Answer 41

Most – 2.5

Patients with metallic heart valves or with recent thromboembolism – 3.5