Specific Guidelines for the diagnosis and treatment of PAD in a diabetic patient with a foot ulcer 2011
From the International Working Group on the Diabetic Foot.
These guidelines are based upon two companion IWGDF papers: "A Systematic
Review of the Effectiveness of Revascularisation of the Ulcerated Foot in Patients
with Diabetes and Peripheral Arterial Disease" and "Diagnosis and treatment of
peripheral arterial disease in diabetic patients with a foot ulcer. A progress report".
Screening and diagnosis
Peripheral arterial disease (PAD) is an important predictor of outcome of ulceration
of the foot in patients with diabetes. The clinician examining a patient with diabetes
and an ulcer of the foot should therefore always evaluate the vascular status of the
lower extremity, specifically looking for signs of ischaemia, as up to 50% of these
patients have PAD. Before a major amputation is undertaken a revascularization
should always be considered and discussed preferably in a multidisciplinary diabetic
In all patients with diabetes and a foot ulcer the presence of PAD must be excluded. The following clinical examination must be performed in all patients:
- A history to identify symptoms of PAD.
- Palpation of pulses in the lower limb (including posterior tibial and dorsalis pedis
The following screening test are nessecary to exclude PAD:
- Hand-held Doppler evaluation of the flow signals from both foot arteries
(dorsalis pedis and posterior tibial).
- Measurement of the ankle brachial index (ABI).
- If there is diagnostic uncertainty, measurement of the toe-brachial index has
additional diagnostic value.
PAD is likely when:
- The patient has claudication or rest pain.
- Both foot pulses are absent to palpation.
- Absent or monophasic Doppler signals are obtained from one or both foot
- The ABI is < 0.9.
- A toe-brachial index <0.7 strongly suggests PAD in a foot acclimatised in a warm
The diagnostic utility of each of these items has limitations in diabetes.
- In patients without symptoms of ischaemia, with palpable foot pulses or with
perfusion measurements suggesting only mild PAD, experts advise to evaluate
the effect of maximal 6 weeks optimal wound care.
- If the wound healing response is poor,
perfusion should be reassessed. Duplex ultrasound or angiography of the arteries
of the lower limb should be strongly considered.
Once the diagnosis of PAD is established, the severity of the perfusion deficit should
- An ABI <0.6 indicates significant ischaemia with respect to wound healing
- An ABI > 0.6 has less predictive value and in these patients toe-pressure and/
or tcpO2 (transcutaneous pressure of oxygen) should be measured.
- Prediction of wound healing based on perfusion testing, regardless of method,
follows a sigmoid curve. Ulceration of the foot in diabetes will often heal if the
toe pressure is >55 mmHg and the tcpO2 >50 mmHg. Healing is usually severely
impaired when toe-pressure is <30 mmHg and tcpO2 <30 mmHg.
If PAD of sufficient severity to impair wound healing is identified, revascularisation
(endovascular or bypass) must be considered in all patients. Exceptions to this
general rule may include: severely frail patients or patients with a short life
expectancy (<6-12 months); patients with pre-existing severe functional impairment
unlikely to be significantly worsened by an amputation; and patients who have such
a large volume of tissue necrosis that the foot is functionally unsalvageable.
Most studies report limb salvage rates after revascularisation procedures between
approximately 80-85% and ulcer healing in > 60% at 12 months.
- The entire lower extremity arterial circulation should be evaluated, with detailed
visualisation of below-knee and pedal arteries.
- One of the following techniques can be used: colour Doppler ultrasound,
multi-detector-row computed tomography angiography (MD-CTA), contrast
enhanced magnetic resonance angiography (CE-MRA) or intra-arterial digital
subtraction angiography (DSA).
- The aim of revascularisation is to restore direct pulsatile flow to at least one of the
foot arteries, preferably the artery which supplies the anatomical region of
- There are no randomised clinical trials comparing open with endovascular
revascularisation techniques in patients with diabetes, a foot ulcer and PAD.
Broadly speaking major outcomes of both techniques appear similar. The results
of both open and endovascular procedures will greatly depend upon the
morphological distribution of PAD as well as the local availability and expertise in
a given centre. The definitive choice for either treatment should be based on a
multi-disciplinary discussion that includes the different vascular specialists involved.
- The peri-operative mortality of these procedures is in most case series < 5% and
major systemic complications are observed in about 10% of the patients.
- Mortality and amputation rates in patients with end stage renal disease are worse.
However, even in these patients favourable results can be obtained, the majority
of studies report 1-year limb salvage rates of approximately 70%.
- "Time is tissue" in infected ischaemic diabetic foot ulcers. Patients with signs of
PAD and a foot infection are at particularly high risk for major limb amputation
and should be treated as a medical urgency, preferably within 24 hours.
- The treatment of PAD should be part of a comprehensive care plan which should
also include treatment of infection, frequent debridement, biomechanical
off-loading, blood glucose control and treatment of co-morbidities.
- Cardiovascular morbidity and mortality are markedly increased in patients with
diabetes, a foot ulcer and PAD; these patients have an overall mortality at 5 years
of 50%. All patients should receive aggressive cardiovascular risk management
that should include support for cessation of smoking, treatment of hypertension
and prescription of a statin as well as low-dose aspirin or clopidogel.