A needle assembly can include a needle and a proximal compartment forming a reservoir for collecting blood that flows through an inner lumen of needle. The needle assembly may also include a needle tip shield for capturing a sharpened distal tip of the needle. The needle tip shield can form a fluid pathway through which blood contained within the reservoir is expelled. The volume of the reservoir can be reduced to cause blood to be expelled from the needle tip shield such as by compressing the proximal compartment or a plunger connected to the proximal compartment or by moving a plunger into the reservoir. The fluid pathway of the needle tip shield can either be the same pathway through which the sharpened distal tip is withdrawn into the needle tip shield, or can be a separate pathway.