Assessment of Macro- and Microcirculation in Contemporary Critical Limb Ischemia

SLR - March 2012 - Jill Peotter

Reference: Kawarada O, Yokoi Y et al. 2011. Assessment of Macro- and Microcirculation in Contemporary Critical Limb Ischemia. Catheterization and Cardiovascular Interventions 78:1051-1058.

Scientific Literature Review

Reviewed by: Jill Peotter
Residency Program: Southern Arizona VA Healthcare System

Podiatric Relevance: 
Many podiatric patients have coexisting vascular disease, and the macro- and microcirculation is often evaluated when treating wounds and determining limb salvage technique. This article evaluates pedal circulation through angiographic findings, assesses the relationship between micro- and macrocirculation, and studies the effect postural changes have on circulation.

Methods: 
A total of 40 critically ischemic limbs in 29 patients who underwent noninvasive evaluation of pedal circulation were included in this study. Patients with history of venous disease or signs and symptoms of venous insufficiency were excluded. All included patients that met criteria for critical limb ischemia including rest pain, with and without tissue loss, significant reduction of skin perfusion pressure (<50mmHg) or lower extremity atherosclerotic occlusive disease as established by angiography. Noninvasive evaluation included ankle brachial index (ABI), and ankle pressure for macrocirculation and skin perfusion pressure (SPP) for microcirculation. All tests were performed in both the supine and dependent positions.

Results: 
In the supine position, the dorsal SPP correlated significantly with ABI (P=0.021, r=0.363) and ankle pressure (P=0.001, r=0.495), whereas plantar SPP did not show a significant correlation to either ABI (P=0.198, r=0.208) or ankle pressure (P=0.185, r=0.214). In the dependent position SPP did not correlate significantly with either ABI or ankle pressure. Postural change from supine to dependent showed a significant increase in SPP (dorsal: 37.2 ± 16.2 to 77.9 ± 17.7mmHg, P<0.001; plantar: 33.6 ± 17.3 to 75.7 ± 18.3mmHg, P<0.001) along with ABI and ankle pressure (ABI: 0.7 ± 0.35 to 0.78 ± 0.42, P=0.003; ankle pressure: 108 ± 61 to 111 ± 60 mmHg; P=0.038).

Conclusions: 
Of microcirculation assessed, only dorsal SPP was significantly correlated with macrocirculation in the supine position. Also, postural changes from supine to dependent position showed an improvement in microcirculation. When treating limbs with critical ischemia one must take into account both macro- and microcirculation as they do not always correlate.