A multi-cannula surgical instrument having an inner cannula movably disposed within an outer cannula, the inner cannula having a blunt distal tip, one or more first inner ducts and one or more first flow-through orifices arranged to allow one or more fluid flows therethrough, where the inner and the outer cannula at the proximal ends thereof are mounted onto a hub that includes a biasing mechanism coupled to the inner cannula and arranged to bias the inner cannula automatically from a retracted towards an advanced position in case of absence of resistance against the inner cannula, wherein the outer cannula comprises one or more second flow-through orifices that are in fluid communication with one or more second ducts arranged between the outer and the inner cannula, wherein the second flow-through orifices, the hub and the second ducts are configured to allow at least one fluid flow therethrough.