Arterial cannula which allows perfusion along opposing directions within a cannulated vessel

A cannula includes at least one opening at a distal tip, and further includes multiple fenestrations that are maintainable in position substantially immediately or slightly beyond a site or point of cannula entry into a vessel. The fenestrations, in combination with the opening(s) at the cannula's distal tip, enable the simultaneous perfusion of blood into the cannulated vessel along multiple directions, including opposing or anti-parallel blood flow directions relative to a central axis of the cannulated vessel. During a medical procedure (e.g., an extra-corporeal membrane oxygenation (ECMO) procedure) blood introduced into a vessel such as the femoral artery by way of the cannula can thus exit the cannula in a manner that provides concurrent blood flow in a first direction towards the heart and a second direction away from the heart.