| abstract |
A needle assembly comprising: a housing (1012) defining an interior of the housing, said housing (1012) comprising at least one cannula (1052) having a patient puncture tip (1038) extending from a first end (1014) of the housing and a non-patient puncture tip (1062) extending from a second end (1016) of the housing, the non-patient puncture tip (1062) and the patient puncture tip (1038) being in mutual fluid communication inside the housing; and a porous vent (920) located inside the housing that separates the interior of the housing into a first chamber and a second chamber, the porous vent (920) including pores for the passage of fluid through it from the first chamber to the second chamber, characterized in that said porous vent (920) includes a blocking element to control the flow of the fluid so that the fluid flows in an axial direction through the porous vent (920), in which the only communication path between the interior of the housing and the external environment is via the patient's puncture tip (1038). |