| Thing | Notes on thing |
|---|---|
| Diagnosis | Is there an infection? Or is it an infection mimic? |
| Organism / likely organism | Bacterial vs fungal vs viral vs parasitic |
| Typical infecting organisms, atypicals, rare orgs | |
| The ‘Microbial sieve’ | |
| Local epidemiology | |
| Empirical vs Definitive Rx | Depends on if you sent samples! |
| Resistance | What Resistance mechanisms have been detected / are likely to be present? Do you have susceptibility testing results? |
| Sensitive vs Resistant vs Resistoid (Sensitive at higher doses / intermediate) | |
| Local resistance data | |
| Site | Where is it / what antimicrobials can reach the site |
| Thing | Explanation of thing |
|---|---|
| Immune status | Immunocompetent? |
| Immunocompromised? | |
| Severity of infection | Mild Sx? Life threatening sepsis? |
| Allergy Hx | Anything you can’t give? Any allergies you can review/remove? |
| Renal function | Poor renal Fn = poor renal penetrance |
| Poor renal Fn = increased toxicity from drug | |
| Liver function | Hepatotoxicity from drug? |
| Some drugs are hepatically excreted, so unsafe to use in severe liver disease | |
| Oral route available? | Nil PO = parenteral ABx |
| ?short gut | |
| ?malabsorption? | |
| PMHx | Comorbidities, e.g. Myasthenia gravis, porphyria, that mean some ABx are inappropriate. |
| Recent ABx use | Increased risk of C.difficile |
| Risk of resistance colonisation | |
| Nonadherence / Nonconcordance / Patient not taking drug | QID regimens worse than BD for this |
| Chaotic patients | |
| Altered mental status | |
| Pregnancy | AKA patient-in-patient. |
| Thingy | Thingsplanation |
|---|---|
| Spectrum | On target effects: the bugs you want to kill |
| Off target effects: the bugs | |
| Duration | Shorter is better |
| Except when it isn’t (looking at you, undrained abscess) | |
| Just google it. | |
| Previous Rx received | Source control? |
| Post-op complications? | |
| Dosing | Usually standardised |
| Dosing ranges can be quite wide; there are situations where the top dose is inappropriate. | |
| Deviate from standard dosing when appropriate for your patient/pathogen | |
| Route | PO vs Parenteral |
| Oral is the new IV | |
| Again, just google it | |
| Tissue penetrance | To target site |
| Expressed usually relative to plasma | |
| Beware protected sites (e.g. CNS, Bone&Joint, Prostate, Biofilm etc). | |
| P450 induction/Inhibition | Important isoenzymes: 3A4, 2C9, 2C19 |
| Induction: PC-BRAS drugs (including rifampicin) | |
| Inhibitors: AO DEVICCES drugs (including Azole antifungals, Macrolides, Ciprofloxacin) |
This is really a subset of interactions, in our humble opinion | | Drug interactions | Like P450 induction/inhibition! But also includes direct drug interactions, e.g. -Warfarin with multiple ABx -Antacids and tetracyclines (lowers tetracycline levels —> less efficacy) -Azole antifungals and Amiodarone (QT prolongation —> TdP) | | Side effects / ADRs | -C.difficile associated diarrhoea and other microbiotoxicities -e.g. Cipro vs Linezolid for BJI; Linezolid is Reserve, so last-resort, but due to terrible FQ side effects Linezolid may be better for the patient -Think common ones vs rare important ones Public Health Wales antimicrobial counselling sheets are particularly useful… | | Bactericidal vs Bacteriostatic | This doesn’t matter. Ignore this. See episode | | WHO AWaRe classification | This isn’t in the diagram as it predate AWaRe e.g. if you have a low-risk Staph aureus bacteraemia and you want to choose a PO switch ABx: -Cotrimoxazole is Access -Clindamycin is Watch -Linezolid is Reserve All 3 were in the SABATO trial, so if you have equipoise you may want to choose them in this rough order… |
When offering Rx options to the patients, think about the BRAN framework:
Cynefin framework:
Example: UTI
