PRESCRIBING FOR THE PSA AND FINALS DR FRANCESCA BONORA

Transcription

1 PRESCRIBING FOR THE PSA AND FINALS DR FRANCESCA BONORA

2 WHAT WE WILL COVER HOW TO PREPARE FOR THE PSA EXAM HOW SCENARIOS APPLY TO PRESCRIBING FOR FINALS

3 THE PSA EXAM

4 For full details of what could be asked: prescribingsafetyassessment.ac.uk/aboutpsa Click on PSA blueprint for November 2017 PDF

5 EXAMPLES OF ITEM STYLES

6 SECTION 1 PRESCRIBING Decide on the most appropriate prescription (drug, dose, route and frequency), based on the clinical circumstances Write a safe, effective and legal prescription 8 questions worth 10 marks each

7 Make sure you sign the prescriptions with your full surname (not initials) don t lose the easy marks

8 HOW TO PREPARE Exam is time pressured, so LEARN TREATMENT ALGORITHMS: Acute conditions eg acute asthma attack, acute heart failure Chronic conditions e.g. depression, reflux oesophagitis Presenting symptoms e.g. pain Find these in the back of the Oxford handbook

9 OXFORD HANDBOOK ALGORITHMS

10 THIS BOOK IS GREAT PASS THE PSA, 1E, FEB 2014, BY WILL BROWN BSC MBBS MRCP(UK) FHEA AND KEVIN W LOUDON

11 ANAPHYLAXIS TREATMENT ALGORTIHMS ACUTE ASTHMA MAKE THESE FOR YOURSELF FOR ALL COMMONEST ACUTE AND CHRONIC MEDICAL CONDITIONS PASS THE PSA, 1E, FEB 2014, BY WILL BROWN BSC MBBS MRCP(UK) FHEA AND KEVIN W LOUDON

12 HOW TO PREPARE If you can t remember use treatment summaries in the online BNF during the exam CTRL + F is your best friend!

13 BNF TREATMENT SUMMARIES CTRL + F

14 PRESCRIBING CONTROLLED DRUGS WHICH IS CORRECT? 29 Andrew Smith 01/10/87 Perrin Lecture Theatre 29 Andrew Smith 01/10/87 Perrin Lecture Theatre MORPHINE SULPHATE 10mg oral tablets Take one tablet, three times daily Please supply 28 (TWENTY-EIGHT) tablets. MORPHINE SULPHATE 10mg oral tablets Take one tablet, three times daily. Please supply 28 10mg (TEN MILLIGRAM) tablets.

15 PRESCRIBING CONTROLLED DRUGS WHICH IS CORRECT? 29 Andrew Smith 01/10/87 Perrin Lecture Theatre 29 Andrew Smith 01/10/87 Perrin Lecture Theatre MORPHINE SULPHATE 10mg oral tablets Take one tablet, three times daily Please supply 28 (TWENTY-EIGHT) tablets. MORPHINE SULPHATE 10mg oral tablets Take one tablet, three times daily. Please supply 28 10mg (TEN MILLIGRAM) tablets. It s the total amount that you need to specify

16 PRESCRIBING CONTROLLED DRUGS Include the name and address of the patient. State the name and strength of the drug State the dose and frequency TOTAL AMOUNT must be written in WORDS AND FIGURES

17 WHAT DOSE SHOULD YOU PRESCRIBE?

18 WHAT DOSE SHOULD YOU PRESCRIBE?

19 SECTION 2 PRESCRIPTION REVIEW Identify prescriptions (drugs, doses or routes) that are inappropriate, unsafe or ineffective from amongst the current list of prescribed medicines 8 items worth 4 marks each

20 PRESCRIPTION REVIEW 11/1/17 PO FUROSEMIDE 40mg 11/1/17 PO PREDNISOLONE 40mg

21 PRESCRIPTION REVIEW 11/1/17 PO FUROSEMIDE 40mg 11/1/17 PO SHOULD BE GIVEN IN MORNING WILL KEEP PATIENT AWAKE! PREDNISOLONE 40mg SHOULD BE GIVEN IN MORNING WILL KEEP PATIENT AWAKE!

22 SPOT THE MISTAKES

23 SPOT THE MISTAKES INCORRECT DOSE SHOULD BE 62.5 MICROGRAMS WHAT TYPE? WRITE UNITS (NOT JUST U ) TECHNICALLY SHOULD BE PRESCRIBED ON THE INSULIN AREA OF THE CHART! WRITE MICROGRAMS IN FULL

24 FLUID CHART ERRORS 11/1/17 0.9% Saline 1 litre KCl 40mmol STAT A.L.S 11/1/17 Red Blood Cells 2 units hours A.L.S 11/1/17 50% Dextrose 1 litre 12 hours A.L.S

25 FLUID CHART ERRORS 11/1/17 0.9% Saline 1 litre KCl 40mmol STAT A.L.S This amount of potassium must be given over at least 4 hours due to risk of arrhythmias 11/1/17 Red Blood Cells 2 units hours A.L.S Each unit needs to be prescribed separately Has to be discarded 4 hours (from leaving the lab) 11/1/17 50% Dextrose 1 litre 12 hours A.L.S 50% Dextrose is irritant to veins. It should only be given in small volumes (20% should preferably be used if trying to reverse hypoglycaemia)

26 SECTION 3 PLANNING MANAGEMENT Deciding which treatment would be most appropriate to manage a particular clinical situation 8 items worth 2 marks each Choose most appropriate treatment from list of 5

27 COMMON ACUTE CONDITIONS KNOW THE TREATMENT ALGORITHMS FOR: STEMI NSTEMI ACUTE LEFT VENTRICULAR FAILURE TACHYCARDIA WITH PULSE ANAPHYLAXIS ACUTE ASTHMA EXACERBATION PNEUMONIA PE GI BLEED BACTERIAL MENINGITIS SEIZURE STATUS EPILEPTICUS STROKE HYPERGLYCEMIA DKA AND HHS AKI POISONING

28 COMMON CHRONIC CONDITIONS KNOW THE TREATMENT ALGORITHMS FOR: HYPERTENSION CHRONIC HEART FAILURE STROKE PREVENTION STABLE ANGINA CHRONIC ASTHMA COPD DIABETES INSOMNIA CONSTIPATION DIARRHOEA PAIN

29 SECTION 4 PROVIDING INFORMATION Decide the most important piece of information that should be provided to patients to allow them to choose whether to take the medicine and to enhance its safety and effectiveness Six items worth 2 marks

30 PROVIDING INFORMATION DRUG RAMIPRIL GLICLAZIDE METHOTREXATE WARFARIN LONG TERM STEROIDS SSRI INSULIN BISPHOSPHONATE INFORMATION STOP IN PREGNANCY TERATOGENIC EAT REGULARLY, DON T SKIP MEALS HYPO RISK REGULAR FBC NEUTROPENIA RISK MONITOR INR - BLEEDING TAKE BISPHOSPHONATE OSTEOPEROSIS RISK DON T STOP SUDDENLY CONTACT DOCTOR IF THOUGHT OF SELF HARM DOSE MAY NEED TO BE INCREASED IF UNWELL TAKE WITH FULL GLASS OF WATER AND REMAIN UPRIGHT FOR 1 HOUR

31 SECTION 5 CALCULATION SKILLS Making an accurate drug dosage calculation based on numerical information Recording answer accurately with appropriate units of measurement 8 items worth 2 marks

32 MAKE SURE YOU PRACTICE Correct number of tablets to achieve a required dose Making necessary dose adjustments based on weight or body surface area Diluting a drug for administration in an infusion pump

33 DRUG RATIOS 1% means 1g in 100ml or 10mg in 1ml for weight/volume (w/v) calculations 1g in 100g for weight/weight calculations

34 ADRENALINE RATIOS ANAPHYLAXIS 0.5mg = 0.5ml of 1 in 1,000 IM Remember 1 in 1,000 means: 1g in 1000 ml or 1000mg in 1000ml or 1ml in 1mg Therefore 0.5ml = 0.5mg CARDIAC ARREST 1mg = 10ml of 1 in 10,000 IV Remember 1 in 10,000 means: 1g in 10,000 ml or 1,000mg in 10,000ml or 1mg in 10ml

35 Dosage Calculations Always convert to the same units and then: D (What you want) H (What you ve got) x V (volume it is in) = Dose Try some practice questions:

36 SECTION 6 ADVERSE DRUG REACTIONS Likely adverse reactions to specific drugs, potentially dangerous interactions, managing adverse effects of a drug 8 items worth 2 marks each

37 ADVERSE DRUG REACTIONS THE CTRL + F SECTION Adverse effects caused by commonly prescribed drugs such as calcium channel blockers, beta2-agonists, non-steroidal anti-inflammatory drugs, aminoglycoside antibiotics, etc. Most likely drug to have caused adverse effect e.g. renal impairment, hepatic dysfunction, hypokalaemia, urinary retention, etc. Potential interactions between medicines e.g. warfarin-statins, inhibitors NSAIDs-ACE How to treat an adverse drug reaction e.g. acute anaphylaxis, excessive anticoagulation, drug-induced hypoglycaemia, diuretic-induced dehydration etc.

38 SPOT THE POTENTIAL ADVERSE EFFECT

39 SPOT THE POTENTIAL ADVERSE EFFECT POTASSIUM BOTH DRUGS CAN CAUSE HYPERKALAEMIA

40 SPOT THE POTENTIAL ADVERSE EFFECT Some drugs causing HYPERKALAEMIA ACE Inhibitors Angiotensin Receptor Blockers (ARB) Beta Blockers Digoxin Heparin NSAIDs Spironolactone Transfusions of RBC Trimethoprim POTASSIUM BOTH DRUGS CAN CAUSE HYPERKALAEMIA

41 WHAT IS THIS PATIENT AT RISK OF?

42 WHAT IS THIS PATIENT AT RISK OF? PHENYTOIN TOXICITY Enzyme inhibitor Enzyme inducer (but relatively less so)

43 ENZYME INHIBITORS AND INDUCERS INDUCERS Increase enzyme activity Reduce drug concentration PC BRAS Phenytoin Carbamazepine Barbituates Rifampicin Alcohol (chronic excess) Sulphonylureas INHIBITORS Reduce enzyme activity Increase drug concentration AODEVICES Allopurinol Omeprazole Disulfiram Erythromycin Valproate Isoniazid Ciprofloxacin Ethanol (acute itntoxication) Sulphonamides

44 WHAT IS THIS PATIENT AT RISK OF? 11/1/17 PO OMEPRAZOLE 40mg 11/1/17 PO PAROXETINE 20mg

45 WHAT IS THIS PATIENT AT RISK OF? 11/1/17 PO 40mg 11/1/17 PO OMEPRAZOLE PAROXETINE Drugs commonly causing HYPONATRAEMIA Thiazide diuretics Amiloride Carbamazepine Sulphonylureas (but not Gliclazide) Proton pump inhibitors Antidepressants, particularly SSRIs ACE inhibitors and ARBs Opiates 20mg

46 NEPHROTOXIC & HEPATOTOXIC DRUGS NEPHROTOXIC ACE Inhibitors Aminoglycosides NSAIDs Methotrexate HEPATOTOXIC Amiodarone Isoniazid Co-amoxiclav NSAIDs Statins Anti-fungals Anti-retrovirals

47 PENICILLIN ALLERGY FLUCLOXACILLIN ERYTHROMYCIN AMIKACIN MEROPENEM CO-AMOXICLAV TAZOCIN METRONIDAZOLE RIFAMPACIN CEFTRIAXONE AVOID CAUTION SAFE

48 PENICILLIN ALLERGY

49 ALLERGIC REACTION MANAGEMENT A patient recently given Tazocin despite a Type 1 Penicillin allergy develops shortness of breath, stridor and a widespread urticarial rash. Choose 3 appropriate treatments: A) Chlorphenamine 4mg, PO B) Adrenaline 10ml of 1:10000, IV C) Adrenaline 10ml of 1:10000, IM D) Adrenaline 0.5ml of 1:1000, IV E) Adrenaline 0.5ml of 1:1000, IM F) Hydrocortisone 200mg, IV G) Chlorphenamine 10mg, IV

50 ALLERGIC REACTION MANAGEMENT A patient recently given Tazocin despite a Type 1 Penicillin allergy develops shortness of breath, stridor and a widespread urticarial rash. Choose 3 appropriate treatments: A) Chlorphenamine 4mg, PO only after resuscitation B) Adrenaline 10ml of 1:10000, IV cardiac arrest, 1mg C) Adrenaline 10ml of 1:10000, IM never used D) Adrenaline 0.5ml of 1:1000, IV never used E) Adrenaline 0.5ml of 1:1000, IM e.g. 0.5mg F) Hydrocortisone 200mg, IV G) Chlorphenamine 10mg, IV

51 SECTION 7 - DRUG MONITORING How to monitor the beneficial and harmful effects of medicines. 8 items worth 2 marks

52 DRUG LEVEL MONITORING - EXAMPLES Some detail on specific drugs: Drug Half-life Timing Toxic Level* Major Toxic Effects Gentamicin 2h Trough After 2-3 doses >2mcg/ml Nephrotoxity, irreversible ototoxicity Phenytoin 20-40h Trough After 2-3 days Total >20mcg/ml Free >2mcg/ml Nystagmus, diplopia, ataxia, confusion, hyperglycaemia Aminophylline 4-16hr N/A 4-6hrs after starting IV infusion Theophylline Trough 5 days >20mcg/ml Arrhythmias, convulsions, hypotension Digoxin 24-36h Trough 1 week >2ng/ml Arrhythmias, visual disturbance, anorexia

53 OTHER DRUG MONITORING DRUG WARFARIN LEVOTHYROXINE ACE INHIBITORS / DIURETICS CLOZAPINE ORAL CONTRACEPTION MONITOR INR TFT (CHANGE DOSE EVERY 4 WEEKS) U&Es FBC BLOOD PRESSURE

54 GENTAMICIN DOSING Hartford nomogram: guides when to give patient next dose, based on blood concentration and the time the measurement was taken E.g. if concentration is 8mg/ml, 8h after start of infusion what is correct dosing interval?

55 GENTAMICIN DOSING Hartford nomogram: guides when to give patient next dose, based on blood concentration and the time the measurement was taken Answer: 36h

56 SECTION 8 DATA INTERPRETATION Make an appropriate change to a prescription based on results of investigations 6 items worth 2 marks

57 PARACETAMOL OVERDOSE Activated charcoal: consider if >150mg/kg has been taken within a 1 hour period. N-acetylcysteine (NAC): Single overdose check level at 4h and use the nomogram (use nomogram when OD has been taken between 4-8h ago) If plasma concentration levels are above the treatment line then you need to treat Staggered overdose (>1h) cannot accurately calculate levels so treat

58 PARACETAMOL OVERDOSE E.g. Patient takes 10 paracetamol tablets at Blood test taken at Paracetamol concentration 0.4mmol/litre

59 PARACETAMOL OVERDOSE DON T TREAT

60 PRESCRIBING SCENARIOS FINALS All the same scenarios in different formats OSCES Prescribe warfarin Prescribe an IM injection eg vitamin B12 Spot the prescription errors Write fluid prescription and calculate drip rates Presenting a history and giving treatment recommendations eg hypertension WRITTEN PAPER Know your treatment algorithms for acute and chronic conditions Data interpretation questions remember side effects of drugs and how they can affect blood results

61 GOOD LUCK!!