Anaerobic Line Draw aspirating syringes, with a liquid sodium heparin concentration of 23.5 I.U. per mL, allows for blood sampling directly from an arterial line. The syringes use a specially formulated electrolyte-balanced liquid sodium heparin that offsets both binding and dilution factors by chemically pre-adjusting key electrolytes to normal blood levels. This provides consistent and accurate analysis for all parameters tested.