Topic Six: Stage 6 - The Unsalvageable Foot
Once an ulcer has developed, there is an increased risk of wound progression that may ultimately lead to amputation. It has been estimated that every 20 seconds, a lower limb is amputated due to complications of diabetes (Hinchcliffe et al., 2012). Unfortunately, some Stage 5 feet will not improve despite interventions taken to treat severe infection or re-perfuse the limb. Amputation may then become necessary.
Amputation may be indicated in the following circumstances:
- A massive acute reduction in arterial perfusion leading to necrosis that spreads up the foot
- Ischaemic rest pain that cannot be managed by analgesia or revascularisation
- A life-threatening foot infection that cannot be managed by other measures
- An unstable, and inoperable Charcot hind foot where external fixation or internal fixation is not possible.
- A non-healing ulcer that is accompanied by a higher burden of disease than would result from amputation. In some cases, for example, complications in a diabetic foot render it functionally useless and a well-performed amputation is a better alternative for the patient.
(IDF, 2012; IWGDF, 2019)
Major amputation in a neuropathic foot should be a very rare event and is usually only necessary when the infection has irretrievably destroyed the foot (Edmonds & Foster, 2014).
Patients needing major amputation have significant co-morbidity and are at high risk for peri-operative complications. Amputations should be managed by a multidisciplinary team consisting of surgeons, physiotherapists, occupational therapists, nurses, podiatrists and rehabilitation doctors.
It has been suggested that up to 85% of amputations can be avoided when an effective care plan is adopted (Pecoraro et al., 1990).
Dressings
Most dressings are designed to create a moist wound environment and support progression towards wound healing (Wounds International, 2013); an ideal wound dressing should provide a moist wound environment, offer protection from secondary infections, remove wound exudate and promote tissue regeneration (Moura et al., 2013).
Sterile non-adherent dressings should be used to cover all open diabetic foot lesions to protect them from trauma, absorb exudate, reduce infection and promote healing. In the absence of strong evidence of clinical or cost-effectiveness, health care professionals should use wound dressings that best match the clinical appearance and site of the wound, as well as patient preferences (NICE, 2011; Wounds UK, 2021).
Dressing choice must begin with a thorough patient and wound assessment.
Factors to consider when selecting dressings include:
- Location of the wound
- Extent (size/depth) of the wound
- Amount and type of exudate
- The predominant tissue type on the wound surface
- Condition of the periwound skin
- Compatibility with other therapies (e.g. contact casts)
- Wound bioburden and risk of infection
- Avoidance of pain and trauma at dressing changes
- Quality of life and patient wellbeing
(Wounds International, 2013; Nair et al., 2020)
The status of the diabetic foot can change very quickly, especially if the infection has not been appropriately addressed. The need for regular inspection and assessment means that dressings designed to be left in situ for more than five days are not usually appropriate for DFU management (Wounds International, 2013).