Prescription review: a foolproof plan Flashcards
Key points: question 1
- Haemoptysis (blood in sputum), so stop aspirin (an antiplatelet) and prophylactic enoxaparin (a low molecular weight (LMW) heparin)
- Hyperkalaemic, so stop the ACE-inhibitor (ramipril) (may contribute to renal failure) and IV fluid containing potassium (and start an alternative).
- Penicillin allergy, so stop co-amoxiclav and start an alternative
- This patient is receiving 6 g/day of paracetamol (i.e. 2 g more than the maximum dose): the frequency should be
6-hourly not 4-hourly.
PReSCRIBER mnemonic to avoid common pitfalls
● Patient details
● Reaction (i.e. allergy plus the reaction)
● Sign the front of the chart
● check for Contraindications to each drug
● check Route for each drug
● prescribe Intravenous fluids if needed
● prescribe Blood clot prophylaxis if needed
● prescribe antiEmetic if needed and
● prescribe pain Relief if needed.
What must you add to a new chart
3 pieces of PID
What do co-amoxiclav and Tazocin both have
Penicillin
Important groups of drugs to be aware of contraindications (4)
- Drugs that increase bleeding
- Steroids
- NSAIDs
- Antigypertensives
- Drugs that increase bleeding
Drugs that increase bleeding (aspirin, heparin and warfarin) should not be given to patients who are bleeding, suspected of bleeding, or at risk of bleeding (e.g. those with a prolonged prothrombin time due to liver disease).
Do not forget that prophylactic heparin is contraindicated in acute ischaemic stroke due to the risk of bleeding into the stroke.
If presents with excessive coagulation, check for enzyme inhibitors e.g. erythromycin –> can increase warfarin’s effect (and thus the prothrombin time (PT) and international normalized ratio (INR)) despite a stable dose.
- Steroids
Remember side effects (/contraindications) as STEROIDS:
Stomach ulcers
Thin skin
Edema
Right and left heart failure
Osteoporosis
Infection (inc candida)
Diabetes (commonly causes hyperglycaemia and uncommonly progresses to diabetes)
cushing’s Syndrome
- NSAIDS
NSAID:
No urine (i.e. renal failure)
Systolic dysfunction (i.e. heart failure)
Asthma
Indigestion (any cause)
Dyscrasia (clotting abnormality).
While aspirin is technically a NSAID, it is not contraindicated in renal or heart failure, or in asthma.
- Antihypertensives
Think of the side effects in three categories:
a. Hypotension (including postural hypotension) that may
result from all groups of antihypertensives.
b. Dividing the groups of antihypertensives into two
mechanistic categories:
1. BB and CCB –> Bradycardia
2. ACEi and diuretics –> Electrolyte disturbance
c. Individual drug classes have specific side effects:
1. ACE-inhibitors –> dry cough.
2. Beta-blockers –> wheeze in asthmatics; worsening of acute heart failure (but helps chronic heart failure).
3. Calcium-channel blockers –> peripheral oedema and flushing.
4. Diuretics –> renal failure.
Loop diuretics (e.g. furosemide) can also cause gout
Potassium-sparing diuretics (e.g. spironolactone) can cause gynaecomastia
Route
If patient vomiting –> IV/IM/SC
Doses for common antiemetics are usually the same regardless or route e.g. metoclopramide 10mg 8-hrly and cyclizine 50mg 8hrly
PATIENTS WHO ARE NBM STILL NEED THEIR ORAL MEDICATION
Intravenous fluids: when do you prescribe them (2 situations)
- Replacement
- Maintenance
Replacement fluids: what to prescribe usually
Always 0.9% NaCl (crystalloid), unless:
Replacement fluids: if hypernatraemic or hypoglycaemic
5% dextrose
Replacement fluids: ascites
Human Albumin Solution - maintains oncotic pressure + higher sodium concentration would worsen ascites
Replacement fluids: shocked with BP <90mmHg
Gelofusine (colloid) - high osmotic content, so stays intravascular for longer, maintaining BP
Replacement fluids: shocked from bleeding
blood transfusion, colloid if no blood available
Replacement: how much fluid and how fast? - what to assess first
Start by assessing
the HR, BP and urine output
Replacement: how much fluid and how fast? - if tachycardic or hypotensive
500 mL bolus immediately
(250 mL if HF) then reassess patient, especially HR, BP and urine output to assess response and speed of next bag of IV fluid.