Delays to Revascularisation and Outcomes of Non-elective Admissions for Chronic Limb Threatening Ischaemia: a UK Population Based Cohort Study.

Objective: Major amputation and death are significant outcomes after lower limb revascularisation for chronic limb threatening ischaemia (CLTI), but there is limited evidence on their association with the timing of revascularisation. The aim of this study was to examine the relationship between time from non-elective admission to revascularisation and one year outcomes for patients with CLTI.

Methods: This was an observational, population based cohort study of patients aged ≥ 50 years with CLTI admitted non-electively for infra-inguinal revascularisation procedures in English NHS hospitals from January 2017 to December 2019 recorded in the Hospital Episode Statistics database. Outcomes were death and ipsilateral major amputation rate at one year. Logistic regression models were fitted to explore the relationship between time to revascularisation and death, adjusted for patient and admission factors. For major amputation, multinomial logistic regression models were used to account for the competing risk of death.

Results: A total of 10 183 patients (median age 75 years) were included in the analysis, of which 67.1% (n = 6 831) were male and 57.6% had diabetes. In patients with tissue loss, the unadjusted one year mortality rate was 30.0% (95% confidence interval [CI] 28.9 - 31.0%), and for every one day increase in time from admission to revascularisation, the adjusted odds of one year mortality increased by 3% (odds ratio 1.03, 95% CI 1.02 - 1.04). In the absence of tissue loss, the unadjusted one year mortality rate was 19.9% (95% CI 18.4 - 21.4%) and there was no evidence of an association with time to revascularisation. There was also no significant association between the time to revascularisation and risk of ipsilateral major amputation at one year irrespective of tissue loss.

Conclusion: Patients undergoing infra-inguinal revascularisation during non-elective admissions for CLTI have high one year major amputation and mortality rates. Longer time from admission to revascularisation was independently associated with higher mortality in patients with tissue loss, but not in those without.