Non-surgical interventions for preventing contralateral tissue loss and amputation in dysvascular patients with a primary major lower limb amputation.

Rationale: Major lower limb amputation (LLA, above the ankle) is performed for people with intractable pain, life-threatening infections, or non-functional limbs. Of 7500 LLAs carried out in England between 2015 and 2018, the majority of these were performed in dysvascular patients. Dysvascularity is the absence of adequate blood supply to maintain a limb's usual function (ischaemia, usually caused by peripheral arterial disease or diabetes mellitus), ultimately leading to pain and tissue injury (ulcers, gangrene, sometimes referred to as tissue loss). Among those who undergo dysvascular LLA, 5.7% and 11.5% will likely undergo contralateral LLA at one and five years respectively, which is associated with greater disability and lower likelihood of returning to work, increasing the psychological burden to the patient and socioeconomic cost to the patient and health service. While extensive research has been carried out in the management of peripheral arterial disease and the care of diabetic feet, there are no guidelines for practice on prevention of contralateral amputation.

Objectives: To assess the effects of non-surgical interventions versus placebo, no intervention, or other non-surgical interventions on contralateral limb (CLL) tissue loss and amputation in dysvascular patients with a primary major LLA.

Search methods: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and PEDro databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers until 20 March 2023. We also checked the references of identified studies and contacted study authors and manufacturers of relevant products.

Eligibility criteria: We aimed to include all randomised controlled trials (RCTs) and quasi-RCTs (e.g. randomised by birthdate) comparing the effectiveness of a non-surgical intervention with placebo, no intervention, or other non-surgical intervention, in adults with a primary major LLA due to dysvascularity. Interventions could be physical, pharmacological, educational, behavioural, or organisational, and delivered by a healthcare professional or carer.

Outcomes: Our critical and important outcomes of interest were as follows. Critical outcomes • Incidence of new localised tissue injury or ulceration (tissue loss) of the CLL, regardless of stage or classification at given time points. • Time to the development of any localised tissue injury or ulceration (tissue loss) of the CLL, regardless of stage or classification. • Incidence of new minor amputation (through the ankle, foot, or toe(s)) of the CLL at given time points. • Time to new minor amputation (through the ankle, foot, or toe(s)) of the CLL. • Incidence of new major amputation (whole limb or partial limb, above the ankle) of the CLL at given time points. • Time to new major amputation (whole limb or partial limb, above the ankle) of the CLL. Important outcomes • Survival (time to death from all causes) at 12 months. • Patient-reported outcome measures of health-related quality of life (HRQoL) using validated scales such as the 12-item Short Form Health Survey (SF-12) and EQ-5D. • Adverse events (e.g. infections in the CLL). • Hospital readmission.

Risk of bias: We used Cochrane's RoB 1 tool to assess risk of bias in the included study.

Synthesis methods: We were only able to perform a narrative review due to lack of data. We reported risk ratios (RR) with 95% CIs for dichotomous outcomes. We used GRADE to assess the certainty of evidence for each outcome.

Included studies: We found one eligible study, which compared electrostimulation of the gastrocnemius muscle and standard rehabilitation against standard rehabilitation in 50 dysvascular amputees.

Synthesis of results: There was no new incidence of tissue loss reported. The following outcomes were not reported: time to new tissue loss; time to and incidence of minor amputation; HRQoL outcomes; adverse events; and hospital readmissions. Electrostimulation was associated with a three-fold reduction in the incidence of new major amputation of the CLL (RR 0.33, 95% CI 0.04 to 2.99), although time to new major amputation was not reported. There was no difference between groups in 12-month survival (RR 1.0, 95% CI 0.85 to 1.18). We judged the overall certainty of the evidence (GRADE) as very low across all outcomes, with unclear risk of selection and detection bias and high risk of performance bias.

Authors' conclusions: Despite the care of the CLL being identified as a key research priority by two separate consensus papers, there is insufficient high-quality evidence to address this priority to date. We found only a single RCT suitable for inclusion, and this study was subject to risk of bias. Contralateral limb outcomes should be recorded in future research on dysvascular amputees. Until better evidence and clearer recommendations are available, this topic is likely to remain a research priority.

Funding: This Cochrane review had no dedicated funding.

Registration: Protocol available via DOI 10.1002/14651858.CD013857.