We are in the process of adopting a protocol for antibiotic lock therapy from Hershey Medical Center. Our infectious disease physician is spearheading this effort. Hershey just uses a 2 ml fill volume for all catheters. I have been asked if there is some other, more precise way of calculating fill volumes for the instillation since catheters vary in length for each patient. Is there a formula to use incorporating catheter length or is using 2 ml across the board a safe way to go?
Each brand of catheter will have the priming volume for each size of catheter included in the instructions for use booklet. This booklet is included in each sterile package for all types of catheters. The numbers listed will be the fill volume for the catheter as it comes from the manufacturer, however trimming to a patient specific length will change this. You can find a formula for this calculation in this reference:
1. Lawson M, Vertenstein MJ. Methods for determining the internal volume of central venous catheters. Journal of Intravenous Nursing. 1993;16(3):148-155.
Lynn Hadaway, M.Ed., RN, BC, CRNI
www.hadawayassociates.com
Lynn Hadaway, M.Ed., RN, NPD-BC, CRNI
Lynn Hadaway Associates, Inc.
PO Box 10
Milner, GA 30257
Website http://www.hadawayassociates.com
Office Phone 770-358-7861
I made a chart with calculations already made for 5cm increments of each lumen of all of the different types of trimmable CVADs that we use, as well as the priming volumes for the non-trimmable catheters. Bard Access also provides a formula for Power Ports.
This information is part of the ALT ordering process, and available to nursing staff.
Mari Cordes, BS RN
Mari Cordes, BS RNIII VA-BC
Vascular Access Department
University of Vermont Medical Center
Hey Mari
Hope to see you at AVA this year as I will be there. Today, however, I think my brain is still home in the bed sleeping, forgive me for asking but what is the ALT ordering process as I would like to have a copy of this chart you made. thanks.
I've attached the chart (a previous version without the increments is in the downloads section of iv-therapy.net).
Because our facility uses mostly Bard products - these are mostly Bard priming volumes. Note that you can also use the direct measurement method to determine.
I will be checking these computations with the Lawson method - if there are major differences, I'll let you know.
Hi Karen - I will see you at AVA!
Mari Cordes, BS RN
Mari Cordes, BS RNIII VA-BC
Vascular Access Department
University of Vermont Medical Center