Data Interpretation Flashcards
What are some causes of a neutropenia?
Clozapine (agranulocytosis)
Carbimazole
Chemo/radiotherapy
(Viral infection- most common in real life)
What are some drug causes of neutrophilia?
Steroids
What are some drug causes of thrombocytopenia?
Penicillamine - reduces production
Heparin
What can cause hypovolaemic hyponatraemia?
Diuretics
What are some causes of hypokalaemia?
DIRE: Drugs- loop and thiazide diuretics Inadequate intake or intestinal loss Renal tubular acidosis Endocrine (cushings and conns syndrome)
What are some causes of hyperkalaemia?
DREAD: Drugs e.g. K-sparing diuretics and ACEI Renal failure Endocrine (addisons disease) Artefact: common, due to clotted sample DKA
What are some drug causes of AKI?
(NB all renal) Nephrotoxic antibiotics, especially gentamicin, vancomycin and tetracyclines ACEI NSAIDs Radiological contrast
What drugs may cause cholestasis?
NB: All cause posthepatic (obstructive) Flucloxacillin Coamoxiclav Nitrofurantoin Steroids Sulphonylureas
What drugs may cause hepatitis and cirrhosis?
Paracetamol OD
Statins
Rifampicin
What does a raised urea indicate?
Kidney injury or upper GI haemorrhage (break down of Hb tourea)
Therefore also look at Hb of a patient with raised urea in patients with normal Cr who are not dehydrated.
How should you change the levothyroxine dose according to a patient’s TFTs for the PSA?
Target TSH range 0.5-5 mIU/L
5: Increase dose
Unless grossly hypo/hyperthyroid, change by smallest increment offered
How can you roughly calculate the normal PaO2 from a patient on oxygen?
Subtract 10 from the FiO2. if the PaO2 exceeds the calculated number then the patient is not hypoxic.
E.g. Patient on 60% O2 with FiO2 of 30kPa is hypoxic- expect 50kPa+
What are the most common drugs requiring monitoring to ensure they stay within their therapeutic index?
Digoxin Theophylline Lithium Phenytoin Abx e.g. gentamicin and vancomycin
How should you manage a patient with an inadequate drug response and low serum drug level
Increase dose- generally by smallest increment possible.
Especially important if a drug has zero-order kinetics e.g. phenytoin as a small dose increase will cause a large clinical effect, with higher risk of toxicity
How should you manage a patient with adequate response to a drug and reduced or normal drug levels?
No change in dose required- clinical effect more important.
How should you manage a patient with adequate response to a drug and high drug levels?
Decrease dose
How should you manage a patient with adequate response to a drug and high drug levels and/or evidence of toxicity?
Omit drug for few days
Exception: Gentamicin- high serum level without signs of toxicity –> decreased frequency by 12 hours rather than reducing dose
How should you manage a patient on gent with high serum levels and no signs of toxicity?
Decrease dose frequency by 12 hours rather than reducing dose
How would you manage a patient with evidence of toxicity, regardless of drug levels?
3 options:
1) Stop drug +/- alternative if required
2) Supportive measures (usually IV fluids)
3) Give antidote if one available
What are features of digoxin toxicity?
Confusion
Nausea
Visual halos
Arrhythmias
What are features of lithium toxicity?
Early: Tremor
Intermediate: Tiredness
Late: Arrhythmias, seizures, coma, renal failure, DI
What are features of phenytoin toxicity?
Gum hypertrophy
Cerebellar symptoms: Ataxia, nystagmus
Peripheral neuropathy
Teratogenicity
What are features of gentamicin toxicity?
Ototoxicity
Nephrotoxicity
What are features of vancomycin toxicity?
Ototoxicity
Nephrotoxicity
What are the target INRs for most patients on warfarin?
2.5
In what instances would patients have a target INR of 3.5?
Recurrent thromboembolism while on warfarin
Metal replacement heart valve
What are indications for giving emergency reversal of warfarin in a patient?
Major bleed e.g. causing hypotension or bleeding into a confined space e.g. brain or eye
How would you manage a patient requiring emergency reversal of warfarin?
Stop warfarin
Give 5-10mg IV vitamin K
Give prothrombin complex (e.g. Beriplex)
How would you manage a patient who is over anticoagulated with an INR >6?
Reduce warfarin dose
How would you manage a patient who is over anticoagulated with an INR 6-8?
Omit warfarin for 2 days then reduce dose
How would you manage a patient who is over anticoagulated with an INR >8?
Omit warfarin and give 1-5mg oral vitamin K
How would you manage a patient who has minor bleeding with INR >5?
Omit warfarin, give 1-5mg oral vitamin K
