Skin microvascular morphology and hemodynamics during treatment with veno-arterial extra-corporeal membrane oxygenation

Abstract

OBJECTIVES: To explore the potentials of microcirculatory assessments for predicting outcome of patients treated with extra corporeal membrane oxygenation for cardiogenic shock. METHODS: Eight patients with acute cardiogenic shock treated with ECMO and eight healthy controls were examined with skin vital microscopy and laser Doppler perfusion measurements. RESULTS: Three patients died on ECMO (group 1). Five patients were successfully weaned off ECMO (group 2). Four patients were discharged from hospital and one died after successful weaning from bleeding complications. Patients surviving ECMO (group 2) had microcirculatory findings comparable with healthy controls. Patients in group 1 showed major skin microvascular pathology: pericapillary bleedings (n = 1), pericapillary dark haloes (n = 2) and capillary micro thrombi (n = 1). As compared with survivors they had lower functional capillary density (FCD) (n = 3), higher heterogeneity of functional capillary density (n = 3) and significantly reduced capillary mean flow-categorical velocity (n = 2). Laser Doppler measurements in group 1 had non-significant lower laser Doppler flux values as compared with survivors and controls. CONCLUSION: Skin microvascular pathology as detected with video microscopy (pericapillary bleedings or haloes, microthrombi/capillaries with "no flow", low FCD with high spatial distribution heterogeneity or low mean flow-categorial velocity) seems to be associated with poor prognosis.

Acute skin trauma induces hyperemia, but superficial papillary nutritive perfusion remains unchanged

“…The present study confirmed in accordance with previous studies that with the CAVM technique, it is possible to assess perfusion and vascular density in the nutritive papillary capillaries of the skin separately. 7,8,[14][15][16][17] Systemic circulatory failure can best be defined as lack of capacity of the circulatory system to deliver sufficient amounts of oxygen to the cells. 8 Capillary perfusion is regulated based on local metabolic needs in both the skin and in other tissues like in the brain.…”

“…7,8,[14][15][16][17] Systemic circulatory failure can best be defined as lack of capacity of the circulatory system to deliver sufficient amounts of oxygen to the cells. 8 Capillary perfusion is regulated based on local metabolic needs in both the skin and in other tissues like in the brain. We therefore hypothesize that systemic circulatory failure, for example, in patients with acute heart failure, hypovolemic, or septic shock, can be evaluated based on CAVM examination of skin microcirculation.…”

“…1), can occasionally be seen and were not counted as capillaries. 8 These vessels were located deeper in the skin. When focusing the microscope on the papillary capillaries (see Figure 1), these larger vessels were out of focus.…”

“…With the CAVM technique, capillary morphology and physiology can be visualized and described according to size, shape, density, and blood flow velocity. 7,8,[14][15][16][17] Capillaries were defined as microvessels with a diameter <15 μm. Not all capillaries in a tissue are perfused at a given per millimeter line (c/mm).…”

“…These techniques have been applied in studies of patients with acute heart failure and in healthy and sick newborns. [7][8][9] The measuring depth of the DRS and CAVM methods has been estimated in theoretical models, 10,11 but it remains to be shown that the two techniques in humans assess papillary nutritive perfusion only.…”