a surgical access port that includes a cylindrical member having a proximal end and a distal end and defining a longitudinal axis ; at least two lumen extending through the cylindrical member along the longitudinal axis ; at least one cavity defined in the cylindrical member and positioned radially within the at least two lumen ; and a source of inflation fluid coupled to the at least one cavity , the source of inflation configured to permit selectable inflation of the at least one cavity , whereby inflation of the at least one cavity increases the radial distance between the at least two lumen .