A retrospective study supports the use of the Wound, ischaemia, and foot infection (WIfI) classification system to predict the revascularisation benefit for diabetic patients with chronic limb-threatening ischaemia (CLTI).
The WIfI classification system was developed to stratify the risk of major amputation at one year for patients presenting with CLTI. Recently, this system was used to identify patients most likely to benefit from revascularisation. WIfI scores were used to define the estimated revascularisation benefit quartiles ranging from high benefit (Q1) to questionable benefit (Q4).
“The aim of our study was to evaluate the revascularisation benefit quartiles in a cohort of diabetic patients who had presented with CLTI,” said first author Caitlin Hicks of Johns Hopkins University (Baltimore, USA).
As reported in the October issue of the Journal of Vascular Surgery, researchers from the university’s Diabetic Foot and Wound Service, led by Hicks and senior author Christopher Abularrage, evaluated 136 diabetic patients (187 limbs) who underwent lower extremity revascularisation between 2012 and 2020 at their institution. The primary outcome of their study was one-year major amputation.
Demographic characteristics of these diabetic patients included:
- Age 65±11 years
- 63% male
- Presentation with ulcer (51%), gangrene (43%) or rest pain (6%)
Revascularisation procedures were either endovascular (67%) or open (33%).
The estimated one-year amputation rates for each quartile were:
- Q1 7±4%
- Q2 4±3%
- Q3 7±5%
- Q4 26±8%
Analysis revealed the Q4 group had a significantly greater risk of amputation compared with the Q1 group (hazard ratio 4.3).
For the 137 limbs with greater than one-year follow-up after revascularisation, a total of 16 (12%) required amputation. Nine of these were in the Q4 group.
“Overall, our data support the use of the WIfI benefit of revascularisation quartiles for estimating the one-year major amputation risk for diabetic patients presenting with CLTI,” said Hicks. “We did, however, observe our actual amputation rate in the Q4 group was one half of what was expected. This may be explained by the fact that all of our diabetic patients are treated by our multidisciplinary team, which has been previously shown to have robust limb salvage outcomes.”
“Up to one half of the Q4 patients who underwent amputation did so despite patency of their revascularisation procedure. This suggests wound size and infection burden are the driving factors behind the elevated risk in this group.”
The decision to perform revascularisation in a patient with CLTI must be made carefully, particularly given their often extensive list of comorbidities, researchers said. This study supports the use of the WIfI system to predict which diabetic patients with CLTI might best be served by revascularisation and highlights the importance of multidisciplinary teams for complex medical and surgical patients.