Data interpretation

Question 1

Types of AKI

Answer 1

Question 2

Name causes of anaemia:

Microcytic

Normocytic

Macrocytic

Answer 2

Question 4

Causes of thrombocytosis and thrombocytopaenia:

Answer 4

Question 5

Causes of hyponatraemia

Answer 5

Question 6

Causes of abnormal potassium

Answer 6

Question 7

Which WBCs are raised in

• bacterial infection
• viral infection
• > what else is it affected by?

When are neutrophils decreased

Answer 7

Bacterial

• Neutrophils
  
  • also raised in tissue damage and steroid use

Viral

• Lymphocytes
  
  • also raised in lymphoma and chronic lymphocytic leukaemia

Neutrophils are low in

• viral infection
• Chemo/radiothx
• Clozapine
  
  • Carbimazole

Question 8

What to be aware of with a raised urea?

Answer 8

Maybe because of AKI or upper GI bleed.

So if abnormal urea and normal creatinine (in patient who is not dehydrated), check haemoglobin

-> if dropped -> Upper GI Bleed probable

Question 9

Liver function tests

which are used for what pathology?

Answer 9

Hepatocyte injury or cholestasis

• bilirubin
• ALT/AST
• ALP

Synthetic function

• Albumin
• Vit-K dependent clotting factors measured with PT/INR
  
  • CF II, VII, IX, X

Question 10

What does a raised bilirubin on its own indicate?

Answer 10

post-hepatic jaundice - rarely due to liver. It usually indicates haemolysis - as bilirubin is a breakdown product

Question 11

What does a raised Alk Phos indicate?

Answer 11

Not necessarily post-hep jaundice:

ALKPHOS

Any fracture

Liver damage

K for kancer/krebs

Paget’s disease of bone and Pregnancy

Hyperparathyroidism

Osteomalacia

Surgery

Question 12

Specific causes of deranged liver function tests

Prehepatic

Intrahepatic

Posthepatic

Answer 12

Question 13

What’s the target range for TSH? How do you respond to changes?

Answer 13

Target range: 0.5-5

if <0.5 -> decrease dose by smallest increments offered

if >5, increase dose by smallest increment offered

Question 14

Causes of hypo and hyperthyroidism (1ary and 2ary)

Answer 14

Question 15

Main pathologies to consider on CXR (for PSA)

Answer 15

pneumonia

pulmonary oedema

Question 16

Signs of pulmonary oedema on XR

Answer 16

• cardiomegaly (should be <50% of lung witdth on PA)
• bilateral and fluffy oedema (rather than unilateral -> pneumonia)
• dull costophrenic angles

Then, ABCDE

Alveolar oedema (bat wings), Kerley B Lines, Cardiomegaly, Diversion of blood to upper lobes, pleural effusions

Question 17

ABGs - describe the steps for looking at them.

Answer 17

Check inspired O2 conc. (FiO2)

• pt on O2 should have higher FiO2
• Calculate: if PaO2 > FiO2 - 10, patient is not hypoxic. If PaO2 lower -> hypoxia

Check for resp failure

Type 1 vs Type 2 resp failure

Check acid-base status by looking at pH

acidosis vs alkalosis?

only PaCO2 abnormal - resp cause

only HCO3 abnormal - metabolic cause

Think about causes

Respiratory alkalosis caused by rapid breathing, whether due to disease or anxiety.

Respiratory acidosis has the same causes as type 2 respiratory failure.

Metabolic alkalosis caused by vomiting, diuretics and Conn’s syndrome.

Metabolic acidosis has multiple causes and the most frequent are lactic acidosis, DKA, renal failure and ethanol/ methanol/ethylene glycol intoxication. One can use the anion gap to narrow the cause (but this is beyond the scope of this book).

Question 18

Which drugs have a narrow therapeutic index?

Answer 18

Most common ones are digoxin, lithium, phenytoin, theophylline and some Abx (gentamycin and vancomycin)

Question 19

How to monitor drugs with therapeutic index? 3 basic principles

Answer 19

1. If inadequate response to the drug and low serum drug level then increase dose. In general increase the dose by the smallest possible increment. This is especially important if the drug exhibits zero-order kinetics (such as phenytoin), as a small dose increase will lead to a large clinical effect (with higher risk of toxicity).
2. If adequate response to the drug and normal or low serum drug level then no change to the dose is required, i.e. clinical response is more important. There is no point in increasing the dose just to get the patient into what is generally considered a ‘therapeutic’ range – it’s already therapeutic!
3. If adequate response to the drug and high serum drug level then decrease the dose. If there is evidence of toxicity (see later in chapter) and clearly if the level is very high then omitting the drug for a few days is appropriate. The only exception to this is gentamicin, where a high serum level (without signs of toxicity) should pre-empt a decrease in frequency by 12 h rather than reducing the dose, e.g. changing from every 24 h (daily) to every 36 h (see below for explanation).

Question 20

Signs of drug toxicity for:

Digoxin

Lithium

Phenytoin

Gentamycin

Vancomycin

Answer 20

Question 21

How to use paracetamol nomogram

Answer 21

Question 22

Manage over-anticoagulation with Warfarin using INR

Answer 22

Question 23

What do you do in case of a major warfarin bleed?

Answer 23

If there is a major bleed ie causing hypotension or bleeding into confined space:

• stop warfarin
• give 5-20 mg IV Vit K
• give prothrombin complex (ie Beriplex)

Question 24

Target INR

Answer 24

2.5

unless recent thromboembolism on warfarin or metal replacement heart valve -> 3.5