Acute limb ischemia (ALI) is a common surgical emergency with an incidence of 1.5 per 10 000 people per year (Creager et al., 2012). Historically the management has been challenging with rates of limb loss reported up to 25% and mortality rates up to 15-20% (Norgren et al., 2007). The relationship between time to revascularization and major limb amputation or mortality is well established, with guidelines indicating revascularization be achieved within a critical 6-hour period. While this recommendation is an ideal practice, it is important to recognize that there may be foreseeable delays in treatment due to hospital transfers from peripheral hospital sites as well as late patient presentation and diagnosis. As such, it is imperative to address the implications of delay in revascularization and resultant patient outcomes in this patient population. Our study aims to evaluate the impact of hospital transfers on time-to-revascularization, compare type of interventions and associated outcomes in patients with ALI who require transfer to a tertiary center.

A retrospective review of all cases with lower extremity ALI was conducted on patients presenting to our tertiary hospital between 2010 and 2019. Patient data was collected on patients who were direct admissions from our emergency department or admissions following hospital transfer from a peripheral hospital. This data was compared to evaluate time to revascularization, interventions performed, and postoperative outcomes of patients with direct admission versus patients who were transferred to our hospital.

173 patients presented to our tertiary hospital with lower extremity ALI. Of these cases, 80 were direct admissions while 93 were transfers accepted from another hospital. The median transfer distance was 91.3km. Transfer patients had a significantly higher time of initial assessment to revascularization compared to direct admits (9.83 hours vs. 6.04, p=0.012), however, however, time of symptom onset to revascularization was not significantly different the two groups (24.92 vs. 20.75, p=0.28). The direct admit group had a higher proportion of Rutherford class IIA limbs (50.0%) while the transferred patient group had a higher proportion of class IIB (43.0%) and III (11.8%) ischemic limbs. Thromboembolectomy was the most common treatment intervention for direct presentation and transfer patients; 91.3% and 89.25%, respectively. There was no significant difference in intra-operative fasciotomy between direct admit and transfer patients (31.3% vs. 38.7%, p=0.31) The direct admit cohort had a higher percentage of full recovery with no documented limb deficits at discharge (78.8% vs. 57%, p=0.0024). Additionally, this cohort had a higher percentage of patients who were discharged home (67.5% vs. 46.2%, p<.0001). Alternatively transfer patients experienced higher proportion of major limb amputation (8.6% vs. 2.5%, p=0.039), discharge to another hospital (35.5% vs. 10% p<0.0001) and mortality (16.1% vs. 8.8%, p<0.0001).

Patients with ALI who required transfer to our hospital from a peripheral site suffered from increased major limb amputation and mortality despite similar total ischemic time and interventions, compared to patients who present and are admitted directly from our emergency department.

1. Creager M., Kaufman J., Conte M. Clinical practice. Acute limb ischemia. N Engl J Med. 2012; 366: 2198-2206 2. Norgren L., Hiatt W.R., Dormandy J.A., Nehler M.R., Harris K.A., Fowkes F.G. et al. Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II). J Vasc Surg. 2007; 45: S5-S67