01Purpose and principlesWhat the treatment does and how it fits into care.
Diabetic foot tissue loss often reflects the convergence of neuropathic pressure and PAD. Clinical examination identifies threat but poorly excludes disease: neuropathy masks claudication and rest pain, autonomic dysfunction may warm the skin, oedema obscures contours and medial arterial calcification can elevate ankle pressure. Combine Doppler waveforms, ABPI and toe-based testing. Toe pressure and TcPO2 estimate healing probability, while anatomical imaging defines whether and how blood flow can be restored.
Revascularisation should be considered when an ulcerated diabetic foot has clinical ischaemia, including absent pulses, monophasic or absent waveforms, ankle pressure below 100 mmHg or toe pressure below 60 mmHg; severe thresholds require urgent consultation. Reassess when wound area falls by less than 50% after four weeks of good care. Modality remains individual, but IWGDF conditionally suggests bypass when infrainguinal revascularisation is indicated, an adequate single-segment saphenous vein exists and the person is suitable for either route; evidence certainty is moderate. Endovascular or hybrid treatment may better fit anatomy, urgency, operative risk, expertise or preference.
Key points
- Ulceration with suspected limb ischaemia needs immediate acute referral and multidisciplinary vascular involvement; a normal or high ABPI cannot safely exclude PAD in diabetes.
- Keep purpose-specific thresholds separate: severe ischaemia uses ABI <0.4, ankle <50 mmHg, toe <30 mmHg, TcPO2 <30 mmHg or monophasic or absent waveforms for urgent consultation; prognosis worsens with toe <30 mmHg or TcPO2 <25 mmHg. No single value dictates every decision.
- Revascularisation aims to restore durable in-line flow to at least one foot artery, preferably supplying the ulcer region, while preserving future treatment options.
- Image from the aorta through below-knee and pedal vessels using duplex, CTA, MRA or catheter angiography selected for anatomy, renal function and intervention plans.
- Choose endovascular, bypass or hybrid treatment from disease distribution, suitable vein, operative risk, life expectancy, local expertise and informed patient preference.
- When infection and PAD coexist, drainage, antibiotics and revascularisation are coordinated; neither infection control nor perfusion should be treated as an isolated sequential checklist.
- After the procedure, confirm improved perfusion objectively, continue offloading and wound care, and investigate failure for restenosis, persistent infection or mechanical load.
02Indications, selection and cautionsWho may benefit, who needs urgent treatment and important alternatives.
Very low toe or ankle pressure, low ABPI and monophasic or absent Doppler waveforms signal poor healing potential. Calcification may falsely raise ABPI, so discordant toe and waveform findings deserve greater weight.
Enlargement, edge necrosis, failure of granulation and absent progress despite pressure relief and infection control suggest perfusion is limiting repair. Measure serially rather than relying on photographs alone.
Diabetes often produces long-segment below-knee and pedal disease with relative sparing of proximal vessels. Palpable femoral pulses therefore coexist with severe foot ischaemia and do not settle suitability for intervention.
PAD increases failure of antibiotics and surgery. Wet gangrene, abscess or sepsis may demand drainage first or simultaneous treatment, while some stable tissue loss benefits from inflow before definitive debridement.
Frailty, cardiac and renal disease, expected mobility, available vein, prior interventions, anatomy and the person's goals affect whether limb salvage is proportionate and which method offers durable benefit.
03Assessment before treatmentTests and checks that guide safe selection.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Doppler waveforms, ABPI and TBIFirst step - Why
- Identify PAD with complementary tests and reveal incompressible ankle arteries before relying on one ratio.
- Interpretation and limitations
- Monophasic signals, ABPI below 0.9 or above 1.3, and TBI below 0.70 support PAD. Apparently normal values make disease less likely but never exclude it in an ulcerated diabetic foot.
- 02
Toe pressure or TcPO2 - Why
- Estimate healing and amputation probability and help set vascular urgency when tissue loss is present.
- Interpretation and limitations
- Toe pressure at least 30 mmHg and TcPO2 at least 25 mmHg increase healing probability; lower values increase major-amputation concern. They remain probabilistic and are affected by technique, oedema and local conditions.
- 03
WIfI staging - Why
- Combine wound extent, ischaemia and infection to frame one-year amputation risk and likely revascularisation benefit.
- Interpretation and limitations
- Record component grades rather than quoting a stage without context. WIfI supports communication and prioritisation but does not override emergency features or individual feasibility.
- 04
Anatomical arterial imaging - Why
- Visualise inflow, femoropopliteal, tibial and pedal circulation for endovascular, bypass or hybrid planning.
- Interpretation and limitations
- Duplex is non-invasive; CTA is affected by calcification and contrast; MRA has device and renal considerations; catheter angiography offers high detail and possible same-session treatment.
- 05
Conduit and physiological assessment - Why
- Determine whether bypass is feasible and whether the person can tolerate the proposed limb-salvage strategy.
- Interpretation and limitations
- Map great saphenous vein when bypass is plausible, assess cardiac and renal risk, functional goals, nutrition and infection. Risk modifies modality rather than erasing the vascular indication.
04Treatment approachPreparation, options, escalation and aftercare.
01Urgent pathwaySevere ischaemia or infected tissue lossFirst stepGangrene, ulcer with severe perfusion deficit, rapid deterioration, rest pain, infection or systemic illness threatens the limb.+
- 1Refer immediately when NICE limb-threatening features are present and obtain urgent vascular, surgical and multidisciplinary foot assessment while treating sepsis and infection.
- 2Perform rapid bedside haemodynamic testing when it does not delay care, then obtain complete anatomical imaging to the foot and decide drainage and revascularisation sequence.
- 3DefinitiveRestore direct flow using the safest durable endovascular, bypass or hybrid option, then reassess tissue viability before definitive debridement, closure or minor amputation.
- 4Document post-procedure perfusion and continue offloading, wound care, antibiotics when infected and cardiovascular secondary prevention.
02Preferred branchNon-healing ulcer despite good carePreferredA PAD-associated ulcer shows less than 50% reduction in wound area after about four weeks despite appropriate infection and glucose control, wound care and offloading.+
- 1Repeat clinical and bedside vascular assessment because disease and technical measurements change; seek specialist vascular review despite previously reassuring results.
- 2Image the arterial tree and discuss revascularisation based on wound trajectory, WIfI, anatomy, procedural risk and the person's priorities.
- 3Audit healing after inflow restoration and investigate restenosis, occult infection, osteomyelitis and continued pressure if progress remains poor.
03Modality decisionEndovascular, bypass or hybridAnatomical imaging confirms treatable disease and the team must choose a route to durable foot perfusion.+
- 1If infrainguinal revascularisation is indicated, an adequate single-segment saphenous vein is available and the person is suitable for either route, discuss the IWGDF conditional preference for bypass over endovascular therapy; supporting evidence is moderate-certainty.
- 2Otherwise compare endovascular, bypass and hybrid options using lesion distribution, pedal targets, conduit, prior procedures, urgency, operative and renal risk, expected durability, local expertise and the person’s informed preference; bypass is not a universal rule.
- 3Preserve future options, define surveillance and contingency plans, and avoid a technically successful procedure that does not improve wound perfusion.
05Regimens, contraindications and interactionsTreatment details and the circumstances that modify them.
Clopidogrel
Give clopidogrel 75 mg orally once daily for established symptomatic PAD unless contraindicated; continue long term while benefit exceeds bleeding risk and review around procedures. The SmPC specifies no numeric renal adjustment because experience in renal impairment is limited, so use caution rather than assuming equivalence.Check active bleeding, bleeding disorders, severe hepatic impairment and interactions including omeprazole or esomeprazole; renal impairment has limited therapeutic experience and requires caution without an evidence-based alternate dose. Coordinate perioperative interruption with the vascular team, and avoid routine pregnancy use unless specialist benefit outweighs uncertainty.
Atorvastatin
Offer atorvastatin 80 mg orally once daily for secondary prevention in people with CVD, including symptomatic PAD, unless contraindications, interactions, adverse-effect risk or preference require a lower dose. For a person with CKD, NICE NG238 instead says to start atorvastatin 20 mg once daily for primary or secondary prevention; increase the dose if the lipid target is unmet and eGFR is at least 30 mL/min/1.73 m², but agree any higher dose with a renal specialist if eGFR is below 30 mL/min/1.73 m².Keep two renal statements distinct: the product SmPC reports no pharmacokinetic dose adjustment for renal impairment, while NICE sets a CKD-specific 20 mg starting regimen and specialist agreement boundary for higher doses when eGFR is below 30 mL/min/1.73 m². Check baseline liver enzymes and major CYP3A4 interactions, counsel about unexplained muscle symptoms, and avoid in pregnancy; active liver disease is contraindicated. Reassess for intolerance and measure lipids to confirm response.
06Complications, monitoring and follow-upAdverse effects, response and longer-term review.
- Document toe pressure, TcPO2 or other objective perfusion change after revascularisation rather than relying only on pulse palpation.
- Measure wound area, depth, necrosis and granulation at agreed intervals and coordinate dressings, offloading and infection treatment through the foot team.
- Surveil the treated artery or bypass according to procedure and local pathway, with prompt duplex or imaging for recurrent symptoms or stalled healing.
- Monitor renal function after contrast exposure, access-site or wound complications, antithrombotic bleeding and statin tolerance.
- Continue smoking cessation, glucose, blood pressure and lipid management because the ulcer is also a marker of high myocardial infarction and stroke risk.
07Special situationsVariants, exceptions and circumstances that change the usual approach.
ABPI can reassure falsely
Medial calcification elevates ankle pressure, so a high ratio may coexist with severe tibial disease. Toe measurements and waveform shape help expose this discordance.
Thresholds modify probability
A toe pressure below 30 mmHg raises amputation concern, but infection, wound extent and technical error also matter. Use thresholds to accelerate judgment, not replace it.
Angiosomes guide, not command
Direct flow to the artery supplying the ulcer is desirable when technically feasible, but collateral networks, target quality and durable patency may justify an indirect route.
Success is a healing foot
Angiographic patency is only an intermediate result. Objective perfusion improvement, viable tissue, wound progress and preserved function are the outcomes that validate the procedure.
No-option language evolves
A person labelled unsuitable after one study may benefit from expert re-review, new imaging or another technique. Equally, burdensome salvage may conflict with frailty and personal goals.
08Common pitfallsFrequent interpretation and management errors.
- 01
Accepting a high ABPI as normal in diabetes can delay revascularisation until tissue loss is irreversible.
- 02
Imaging only to the knee misses the infrapopliteal and pedal disease most relevant to an ulcerated diabetic foot.
- 03
Waiting four weeks despite gangrene or severe perfusion deficit misapplies the non-healing reassessment rule to an urgent presentation.
- 04
Choosing a procedure by anatomy alone ignores conduit, infection, renal function, functional outcome and patient preference.
- 05
Stopping wound care after revascularisation assumes blood flow alone removes pressure, necrosis and infection; coordinated care must continue.