Introduction: Temporary arterial shunting is an established method to prevent tissue ischemia. Although less established, shunting might also be achieved through endovascular and hybrid techniques, known as endoshunting. Endoshunting offers advantages, for example avoiding complete occlusion of the donor artery and minimally-invasive access. In an ex vivo bench test, we previously tested volume flow in various interconnected endoshunt systems. In this previous study a combination of an 8 Fr Prelude® Short Sheath introducer (Merit Medical), a 30cm long ¼” perfusion tubing (Sorin Group) and a Distal Limb Perfusion® 10 Fr One-Piece Paediatric Arterial Cannula (Medtronic) was found to have the highest flow capacity (Fig 1). This study aims to investigate the capacity of the best performing endoshunt system in vivo.
Methods: Materials and
Methods: Six anesthetized pigs had their common iliac arteries (CIA) explored, with the left side serving as the experimental and the right CIA as the control. Mean arterial pressure, regional blood flow, endoshunt flow, and regional oxygen extraction and lactate production were recorded. Distal muscle perfusion was monitored using near infrared spectroscopy (NIRS). Each experiment involved baseline registration, cross-clamping of the left CIA, a 120 minutes endoshunt session, and restoration of native flow. (Fig 2)
Results:
Results: During cross-clamping, NIRS values on the experimental side reached the lowest measurable value. Following endoshunt activation, there were no NIRS value differences between the experimental and control extremities whereas the average arterial flow decreased in both experimental (270 to 140 ml/min, p= .028) and control extremities (245 to 190 ml/min, p= .249) with a greater drop on the endoshunted side (48% versus 22%, respectively) (Fig 2). Lactate levels temporarily increased by 42% in the endoshunted limb upon endoshunt activation but were normalized within an hour. Oxygen extraction remained constant at 55% on the control side but increased to 70% in the endoshunted extremity (p= .068).
Conclusions:
Discussion: In this animal model, a flow-optimized endoshunt system appeared to provide sufficient blood flow, restore stable tissue perfusion, and cause only transient lactate production increase. Although arterial flow was slightly lower and oxygen extraction slightly higher on the endoshunted side, the endoshunt seemed to deliver adequate perfusion to prevent significant ischemia.
