Perioperative Outcomes are Adversely Affected by Poor Pretransfer Adherence to Acute Limb Ischemia Practice Guidelines

Abstract

Objectives The accepted treatment for acute limb ischemia (ALI) is immediate systemic anticoagulation and timely reperfusion to restore blood flow. In this study, we describe the retrospective assessment of pretransfer management decisions by referring hospitals to an academic tertiary care facility and its impact on perioperative adverse events.

Methods A retrospective analysis of ALI patients transferred to us via our Level I Vascular Emergency program from 2010 to 2013 was performed. Patient demographics, comorbidities, Rutherford ischemia classification, time to anticoagulation, and time to reperfusion were tabulated and analyzed for correlation to incidence of major adverse limb events (MALE), mortality, and bypass patency in the perioperative period (30-day postoperative). All time intervals were calculated from the onset of symptoms and categorized into three subcohorts (<6 hrs, 6-48 hrs, and >48 hrs).

Results Eighty-seven patients with an average age of 64.0 (± 16.2) years presented to outlying hospitals and was transferred to us with lower extremity ALI. The mean delay from symptom onset to initial referring physician evaluation was 18.3 hrs. At that time of evaluation, 53.8% had Rutherford class IIA ischemia and 36.3% had class IIB ischemia. Seventy-six (87.4%) patients were started on heparin previous to transfer. However, only 44 (57.9%) patients reached therapeutic levels as measured by activated partial thromboplastin time (aPTT) prior to definitive revascularization. A delay of anticoagulation initiation >48 hrs from symptom onset was associated with increased 30-day reintervention rates compared with the <6 hrs group (66.7% vs. 23.5%; p<0.05). However, time to reperfusion had no statistically significant impact on MALE, 30-day mortality, or 30-day interventional patency in our small cohorts. Additionally, patients with a previous revascularization had a higher 30-day reintervention rate (46.5%; p<0.05).

Conclusions The practice of timely therapeutic anticoagulation of patients referred for ALI from community facilities occurs less frequently than expected and is associated with an increased perioperative reintervention rate.