The patient's side of the arterial port
was clamped, and the blood rinsed back from the machine to the patient.
Fluoroscopy showed that contrast injected through the arterial port
of the catheter entered the right atrium and flowed into the pulmonary artery; contrast put into the venous port entered the left atrium and flowed into the aorta (Figure 2).
Until arterial port
systems are designed and commercially available, this treatment would not be widely available or mainstream.
Using the empty 3 milliliter sterile syringe attached to the red arterial port
(the red cap is gone), unclamp catheter port and withdraw 3 milliliters of blood to remove the heparin flush.
Because maintenance and bolus doses of heparin are injected into the venous port of the dialysis circuit and are subsequently diluted in the plasma volume, blood sampled from the arterial port
is unlikely to have concentrations of heparin greater than 2 U/mL.
Prior to the study, our INR sampling method involved a 5 ml blood discard from each port and a 60 ml aspiration from the arterial port of the catheter that was replaced after the INR sample was withdrawn.
One unit withdrew an additional 10 ml of blood before taking the INR sample from the CVC arterial port, while five units withdrew an additional 20 ml of blood prior to sample collection from the CVC arterial port.
The second sample was taken after a 5 ml sample of blood was aspirated and discarded from both CVC ports followed by an additional 20 ml aspiration from the arterial port.
If protocol allows, in adults, using sterile technique, withdraw 10 ml of blood from the arterial port
and save for reinfusion.