Chapter 2: Prescription Review Flashcards
Safe routine for Prescribing
PReSCRIBER
- Patient details
- Reactions (+allergies)
- Sign, front of chart
- Contrainidcations
- Route
- IV fluids
- Blood clot prophylaxis
- (anti)Emetic
- Relief of pain
What to check for P in PReSCRIBER
Patient details
3 pieces of information needed: name + DOB + Hosp #
What to check for Re in PReSCRIBER
Reactions i.e. allergy + the reaction.
Complete or check allergy box before prescribing.
NB: Co-amoxiclav + Tazocin both contain penicillin.
What to check for S in PReSCRIBER
Sign : Front of chart + individual prescription
What to check for C in PReSCRIBER
Contraindications:
BANS: consider 4 groups of drugs.
- Bleeding risk:
- Do not give if patient bleeding or suspected or at risk of bleeding e.g. prolonged PT in CLD.
- Prophylactic heparin CI in acute ischaemic stroke as may bleed into stroke.
- Enzyme inhibitors (AO DEVICES) can increase warfarin’s effect, despite stable dose e.g Erythromycin
- Antihypertensives:
- Hypotension – including postural hypotension, from ALL groups of antihypertensives.
- Bradycardia – B-blockers + CCBs.
- Electrolyte disturbances – ACE-i + diuretics.
- Specific side-effects: ACE-i = dry cough; B-blockers = wheeze in asthmatics + worsening of ACUTE heart failure; CCBs = peripheral oedema + flushing; diuretics = renal failure → loop (+thiazide) diuretics = gout, K+-sparing diuretics (e.g. spironolactone) = gynaecomastia.
- NSAIDs:
- Cautions/CIs = NSAID = No urine (renal failure), Systolic dysfunction (HF), Asthma, Indigestion (any cause) + Dyscrasias (clotting abnormality).
- NB: Although aspirin an NSAID, it is NOT CI in renal or HF, or asthma.
- Steroids:
- S/Es (+ loosely the Cis) = STEROIDS = stomach ulcers, thin skin, edema, R+L HF, osteoporosis, infection, diabetes (mainly hyperglycaemia, rarely progresses to diabetes), syndrome (Cushing’s).
Contraindications: B
Bleeding risk:
- Do not give if patient bleeding or suspected or at risk of bleeding e.g. prolonged PT in CLD.
- Prophylactic heparin CI in acute ischaemic stroke as may bleed into stroke.
- Enzyme inhibitors (AO DEVICES) can increase warfarin’s effect, despite stable dose.
Contraindications: A
Which cause bradycardia?
Which cause electrolyte disturbances?
What can b-blockers worsen in the acute setting?
General sfx of all diuretics? Loop? K+ sparing?
Antihypertensives:
- Hypotension – including postural hypotension, from ALL groups of antihypertensives.
- Bradycardia – B-blockers + CCBs.
- Electrolyte disturbances – ACE-i + diuretics.
- Specific side-effects:
- ACE-i = dry cough;
- B-blockers = wheeze in asthmatics + worsening of ACUTE heart failure;
- CCBs = peripheral oedema + flushing;
- Diuretics = renal failure + loop diuretics = gout, K+-sparing diuretics (e.g. spironolactone) = gynaecomastia
Contraindications: N
NSAIDs:
- Cautions/CIs = NSAID = No urine (renal failure), Systolic dysfunction (HF), Asthma, Indigestion (any cause) + Dyscrasias (clotting abnormality).
- NB: Although aspirin an NSAID, it is NOT CI in renal or HF, or asthma.
Contraindications: S
Steroids: S/Es (+ loosely the Cis) = STEROIDS
- stomach ulcers
- thin skin
- edema
- R+L HF
- osteoporosis
- infection
- diabetes (mainly hyperglycaemia, rarely progresses to diabetes)
- syndrome (Cushing’s)
What to check for R in PReSCRIBER
Dosing of anti-emetics?
Route for each drug.
- Vomiting = give via IV/IM/SC.
- If short-lasting vomiting (which it usually is) = no need to change route of other prescribed medicines.
- Doses of anti-emetics all SAME regardless of route e.g. cyclizine 50mg 8-hourly, metoclopramide 10mg 8-hourly.
- NBM still need their oral medication, including prior to surgery.
What to check for I in PReSCRIBER
IV fluids.
Prescribed in 2 situations: (1) Replacement = if dehydrated/acutely unwell; (2) Maintenance = if NBM.
What to check in replacement fluids?
If the patient is shocked…
What to assess when giving replacement fluids?
Replacement: Which fluid? All 0.9% saline unless:
- Hypernatraemic or hypoglycaemia = give 5% dextrose.
- Ascites = give human-albumin solution (HAS) – maintains oncotic pressure, 0.9% saline worsens ascites.
- Shocked with SBP < 90mmHg = 500 ml 0.9% Sodium Chloride over 15 minutes (250 ml in elderly). (if have to do this, x3, give inotropes - Inotropic agents such as milrinone, digoxin, epinephrine, dopamine, and dobutamine are used to increase the force of cardiac contractions.)
- Shocked with bleeding = 500 ml 0.9% Sodium Chloride over 15 minutes (250 ml in elderly), then like with like (senior decision)
Replacement: How much + how fast? Assess HR, BP + UO first.
- Tachycardic + hypotensive = 500ml IV STAT (250ml if HF) → reassess.
- Only oliguric (not obstruction) = 1L over 2-4h → reassess.
- ↓UO (oliguric <30mL/h, anuric <0ml/h) = 500ml depleted.
- ↓UO + tachycardia = 1L depleted.
- ↓UO + tachycardia + hypotension (i.e. shocked) = >2L depleted.
- General rule – never prescribe >2L IV fluid, as should review rate regularly.
- 0.9% saline 1L 2⁰ = give over 2h – should write “2 hours” or “2-hourly” instead.
What to check in maintenance fluids?
Which fluids + how much?
- Adults need 3L/day of IV fluid OR 25-30ML/KG/DAY. Elderly need 2L/day.
- Adequate electrolytes = 1 salty + 2 sweet = 1L 0.9% saline + 2L 5% dextrose.
- Provide K+ by adding KCl to bags, guided by U&Es. If N K+, need 1mmol of KCl/kg/day. (c.40mmol/day)
- Do NOT give IV K+ at rate of >10mmol/hour.
How fast?
- If giving 3L/day = 8 hourly bags.
- If giving 2L/day = 12 hourly bags.
- Before prescribing, always check: U&Es, not fluid overloaded, bladder not palpable.
What to check for B in PReSCRIBER
Blood clot prophylaxis.
- To prevent VTE, majority get LMWH (e.g. dalteparin 5000U daily SC) + compression stockings.
- Drug charts provide assessment tool.
- Note if bleeding/suspected/at risk (including ischaemic stroke), don’t give warfarin or heparin.
- If peripheral arterial disease, don’t give compression stockings (may cause acute limb ischaemia)
What to check for E in PReSCRIBER
Emesis relief.
- Nauseated = regular anti-emetic vs Not nauseated = as-required anti-emetic:
- Cyclizine 50mg 8-hourly IM/IV/oral → but fluid retention
- Metoclopramide 10mg 8-hourly IM/IV if HF.
- Avoid cyclizine (anti-histamine) if HF, otherwise good 1st-line for almost all cases except cardiac.
- Avoid metocloporamide (dopamine antagonist) if Parkinson’s disease (exacerbates) + young women (dyskinesia, especially acute dystonia).
