Clinician tools - Dr Ed Halvey

Clinician decision tools

Private decision support. Everything runs in your browser and nothing is saved - no patient data is stored on this site.

Perioperative anti-inflammatory prescribing, based on Dr Halvey's algorithm (Halvey EJ, Haslam N, Mariano ER. BJA Education 2023).

1. Rule out contraindications (tick any present)

Yes No

Decision support only - confirm against current product information and local guidance, and use clinical judgement for the individual patient.

Post-arthroplasty VTE prophylaxis: aspirin vs rivaroxaban

Select the procedure and tick any factors present. The tool suggests a pathway, weighing VTE risk against bleeding risk. Set the exact thresholds and agents to your protocol.

Procedure

Higher VTE risk factors

Higher bleeding risk factors

Evidence (decision support only):

CRISTAL (JAMA 2022, Australian, 31 hospitals): enoxaparin 40 mg was superior to aspirin 100 mg for 90-day symptomatic VTE (1.8% vs 3.3%) after THA/TKA. Aspirin is not optimal for every patient.
EPCAT II (NEJM 2018): after 5 days of rivaroxaban, switching to aspirin was non-inferior to continuing rivaroxaban in selected patients - supporting aspirin for lower-risk patients after an initial potent agent.
Duration guide: extended prophylaxis up to ~35 days after THA and ~14 days after TKA.

Confirm against your local protocol and the hip arthroplasty review (BJA Education 2024).

Medicine class	Action before surgery
ACE inhibitors / ARBs	Withhold 24h (omit morning of surgery)
Beta-blockers, CCBs	Continue
Diuretics	Omit morning of surgery
Warfarin	Stop ~5 days; bridge per indication/INR target
DOACs (apixaban, rivaroxaban, dabigatran, edoxaban)	Stop ~2-3 days; longer if reduced CrCl / high bleed-risk surgery (see SCGH CrCl table)
Clopidogrel / ticagrelor / prasugrel	Stop ~5-7 days (weigh stent / ACS risk)
Aspirin (low dose)	Usually continue
SGLT2 inhibitors	Stop 3 days (ketoacidosis risk)
GLP-1 agonists	Continue; modified fasting, consider gastric stasis
Metformin / oral hypoglycaemics	Omit on day of surgery
Insulin	Dose-adjust per fasting protocol (basal 50%)
NSAIDs	Stop 2-3 days (bleeding/renal). Coxibs: little platelet effect
Statins, antidepressants, antiepileptics, inhalers	Continue
Steroids	Continue; consider stress dosing
Oestrogen / HRT / COCP	Consider stopping per VTE risk
Supplements (fish oil, vitamin E, garlic, ginkgo, ginseng, St John's Wort)	Stop ~7 days

Confirm intervals against the SCGH peri-operative medication guideline before use.

Discharge opioid reference (knee / hip)

Procedure	Typical discharge supply (set to your protocol)
Total knee replacement	e.g. tapentadol SR + IR, limited supply, wean by ~6 weeks
Total hip replacement	e.g. tapentadol SR + IR, smaller supply than TKR

Oral morphine equivalent (OME) quick calc

Approximate conversion factors - verify before relying on them. Enter total mg taken.

Total OME: 0 mg

Actual patient opioid-consumption follow-up should be captured in your Microsoft Forms / tenant, not on this website.

Direct links and codes for each plan

Give the patient the direct link (or the code). The link opens their plan straight away - they do not have to choose it from the list. Click a link to open it now.

Plan	Code	Direct link
General - etoricoxib	GEN-ETO	/tools/pain-relief.html?c=GEN-ETO
General - celecoxib	GEN-CEL	/tools/pain-relief.html?c=GEN-CEL
General - ibuprofen	GEN-IBU	/tools/pain-relief.html?c=GEN-IBU
Caesarean section	CAES	/tools/pain-relief.html?c=CAES
ACL reconstruction - celecoxib	ACL-CEL	/tools/pain-relief.html?c=ACL-CEL
ACL reconstruction - etoricoxib	ACL-ETO	/tools/pain-relief.html?c=ACL-ETO
Hip and knee replacement	JOINT	/tools/pain-relief.html?c=JOINT

When the site is live, the full link is https://drhalvey.com.au/tools/pain-relief.html?c=CODE (replace CODE). You can text or email this to the patient, or set up your SMS to include it.

References: Halvey EJ, Haslam N, Mariano ER. Non-steroidal anti-inflammatory drugs in the perioperative period. BJA Education 2023;23(11):440-447. Haslam N, Halvey E, Scott C. Perioperative care of patients undergoing total hip arthroplasty. BJA Education 2024;24(6).