Prescription review

Question 1

Why should an ACE-inhibitor be stopped when a patient is hyperkalaemic?

Answer 1

ACE inhibitors retain potassium, thereby worsening the hyperkalaemia

Question 2

What is the maximum daily dose of paracetamol?

Answer 2

4g/day

Question 3

What is the PReSCRIBER mnemonic?

Answer 3

Patient details
Reaction (i.e. allergy)
Sign the chart
Contraindications
Route
IV fluids (if needed)
Blood clot prophylaxis
anti-Emesis
pain Relief

Question 4

What are the cautions/contraindications to prescribing NSAIDs? (mnemonic- NSAID)

Answer 4

No urine (i.e. renal failure)
Systolic dysfunction (i.e. heart failure)
Asthma
Indigestion
Dyscrasia (i.e. blood clotting disorders)

Question 5

Side effects/cautions of antihypertensives:

a) ACE inhibitors (2)
b) Beta-blockers (2)
c) Calcium blockers (2)
d) Diuretics (2)

Answer 5

a) Dry cough; electrolyte disturbance e.g. hyperkalaemia
b) wheeze in asthmatics; worsening of acute heart failure
c) peripheral oedema; facial flushing
d) renal failure; electrolyte disturbance

Question 6

In what two situations are IV fluids prescribed?

Answer 6

Replacement/resus for a dehydrated/acutely unwell patient

Maintenance fluids for a patient who is nil by mouth

Question 7

Fluids (other than 0.9% NaCl) to give if:

a) hypernatraemic or hypoglycaemic
b) ascites
c) shocked from bleeding

Answer 7

a) 5% dextrose
b) human albumin solution
c) blood if available

Question 8

What factors should be considered when assessing the volume/rate of replacement fluids?

Answer 8

Blood pressure, pulse rate and urine output

Question 9

If a patient is oliguric but BP and pulse are normal, how quickly should fluids be given?

Answer 9

1L over 2-4 hours then re-assess

Question 10

If a patient is hypotensive and/or tachycardic, how quickly should fluids be given, and what volume?

Answer 10

Stat; 500ml unless proven/suspected heart failure (250ml). Then re-assess to determine speed of next bag

Question 11

What is an ideal daily fluid regimen for a normal adult on maintenance fluids?

Answer 11

3L (2L of 5% dextrose, 1L of saline- “1 salty and 2 sweet)

2 x 20mmol potassium chloride

Question 12

What should always be checked if you are prescribing fluids due to reduced urine output?

Answer 12

Whether or not the patient has a palpable bladder- this could indicate urinary obstruction

Question 13

What are the signs of fluid overload? (3)

Answer 13

Increased JVP, peripheral oedema, pulmonary oedema

Question 14

When should a) prophylactic LMWH b) compression stockings not be prescribed?

Answer 14

a) patients bleeding or at risk of bleeding

b) peripheral arterial disease

Question 15

Anti-emetic choice?

Answer 15

Cyclizine 50mg up to 8hrly IM/IV/oral regularly or as required

Question 16

What is the main contraindication to cyclyzine?

Answer 16

Heart failure (causes fluid retention) prescribe metoclopramide 10mg up to 8-hourly IM/IV

Question 17

When should metaclopramide be avoided?

Answer 17

Parkinson’s disease/LBD

Question 18

Regular analgesia for:

a) mild pain
b) severe pain

Answer 18

a) paracetamol 1g qds

b) co-codamol 30/500, 2 tablets 6hrly

Question 19

As-required analgesia for:

a) no pain
b) mild pain
c) severe pain

Answer 19

a) paracetamol 1g up to 6-hourly
b) codeine 30mg up to 6-hourly
c) morphine sulphate 10mg up to 6-hourly

Question 20

What effect do thiazides/loop diuretics have on potassium?

Answer 20

Lower serum K+

Question 21

Which class of drug is domperidone, and why is it potentially safer to use in Parkinsons disease than metoclopramide?

Answer 21

Dopamine antagonist

Doesn’t cross the blood-brain barrier

Question 22

Which class of anti-emetic is cyclizine?

Answer 22

Anti-histamine

Question 23

Under what circumstances should methotrexate be withheld?

Answer 23

If patient is septic (until neutropenic sepsis is excluded)

Question 24

What could be the result of combining a rate-limiting calcium blocker and a beta blocker?

Answer 24

Brady-arrythmia, potential asystole