Forum topic

5 posts / 0 new
Last post
barbara bonito
Tpa volume for Port-a-cath clearance
Given that many port-a-caths have a volume greater than 2 cc, are you still using 2 mg in 2cc, 2 mg in 4-5 cc or 5 mg in 5 cc.  And does anyone have any documentation to support what they're doing.  We spoke to a cath-flo rep who stated that their studies had shown 2mg/2cc effective for all types of caths, including port-a-caths.
Mike Brazunas
Barbara, Great question.


Great question.  

Implantable ports may not have as big a priming volume as you think.  Angiodynamics CT injectable Smart Port (the only one that I have extensive data on) has the following numbers:

 priming volume for all  ports = 0.6 mls

 priming volume 9.6fr silincone = 0.02ml per cm

 Priming volume 8.0 fr poly = 0.02ml per cm

 priming volume 7.5 re silicone = 0.015ml per cm 

 So, a 8fr poly at 20 cms  = port 0.6mls + tube [0.02mlx20cm] 0.4mls = 1ml priming volume.

But of course you also have to add the priming volume or the huber set;

LifeGaurd CT Injectable (again, the only one I have stats on right now)

20ga 1.9cm needle wiht 7" tubing  = 0.21mls

So, a 8fr poly at 20 cms  = port 0.6mls + tube 0.4mls + huber set 0.21mls =1.21mls. total.  At 30cms the total would be 1.41mls

These priming volumes are fairly  standard across all manufactures I think.  However, if there is one with a priming volume greater than 2mls, I haven't come across it.



Mike Brazunas RN




Karen Day
Karen Day's picture
I have seen this

I have seen this demonstrated;  try this - get a sample port and attach a huber needle.  Prime it and you will see that 2ml is definitely enough to reach the end of the catheter. 

According to the procedure for Cath Flo infusion, 2cc is all that is required for any VAD unless the patient is less than 30kg and then the amount is 110% of the intraluminal volume of the device.  Hope this helps.

2 mg cathflow in 3ml sterile

2 mg cathflow in 3ml sterile water.


Andre - 2mg of Cathflo in

Andre - 2mg of Cathflo in 3ml sterile water is new to me...can you explain a bit more?  Maybe a typo? 


Mari Cordes, BS RN 

Nurse Educator IV Therapy
Fletcher Allen Health Care, Burlington VT

Mari Cordes, BS RNIII VA-BC
Vascular Access Department
University of Vermont Medical Center

Log in or register to post comments