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Arterial line tubing is the fluid-filled line that connects an arterial catheter to a pressure transducer so a bedside monitor can display blood pressure continuously. Clinic staff, buyers and students searching this term usually need to know what the parts are, which regulated device each part is, and why tubing affects the pressure waveform. It is also called transducer tubing, pressure transducer tubing or pressure monitoring tubing. This page describes products and general use; it is not medical advice.
Not the dialysis line: in hemodialysis, the “arterial line” is the arterial bloodline that carries blood from the patient to the dialyzer. That is a different product, covered in blood tubing for dialysis. Everything below is about the pressure monitoring set used with an arterial catheter.
Who uses it: critical care and perioperative teams who monitor arterial pressure through an arterial catheter, and the supply staff who stock the sets.
What arterial line tubing is
It is the tubing between the arterial catheter and the pressure transducer, filled with fluid so that pressure changes at the catheter reach the transducer. The transducer converts them to a signal for the monitor. FDA describes the transducer in 21 CFR 870.2850: “An extravascular blood pressure transducer is a device used to measure blood pressure” “by changes in the mechanical or electrical properties of the device,” with its proximal end connected to a pressure monitor (eCFR text, checked 2026-10-30). Arterial catheters themselves are a separate subject; a related device class is described in central venous catheters.
How a pressure monitoring set is built
Sets are sold as a unit, but they are built from distinct functional parts. A published pediatric intensive care study (Joffe et al., Critical Care 2016, open access) describes its arterial line setup as a connector from the catheter, a stopcock, and high pressure tubing with a disposable transducer (an Edwards Lifesciences TruWave 3 cc/72 in (180 cm) pressure monitoring set). That is one study’s configuration, not a standard.
The continuous flush element is regulated on its own. 21 CFR 870.1210 describes a continuous flush catheter as “an attachment to a catheter-transducer system that permits continuous intravascular flushing” “at a slow infusion rate for the purpose of eliminating clotting, back-leakage, and waveform damping.” Fluid delivery to a patient by pump is a different product; see IV infusion pumps.
Types and variants
The names people use for these products map to several FDA device classifications. All three below are Class II. Each row traces to the regulation text or to the openFDA device classification database (checked 2026-10-30).
| Device | FDA product code | Regulation | Class | What the source says |
|---|---|---|---|---|
| Extravascular blood pressure transducer | DRS | 21 CFR 870.2850 | II | Measures blood pressure by changes in the mechanical or electrical properties of the device; connects to a pressure monitor |
| Continuous flush catheter | KRA | 21 CFR 870.1210 | II | Attachment to a catheter-transducer system for continuous slow flushing to eliminate clotting, back-leakage and waveform damping |
| Pressure transducer, catheter tip | DXO | 21 CFR 870.2870 | II | Listed in openFDA as a separate classification; a different device from the external transducer |
Sizes and specifications that matter
| Item | Value in source | Context |
|---|---|---|
| Pressure monitoring set | 3 cc, 72 in (180 cm) | Edwards Lifesciences TruWave set used in one pediatric ICU study |
This is the value that study reported for its own setup. It is not a recommended length or volume; check the labelling of the product you stock.
Why tubing affects the waveform
The signal travels through fluid, so anything that changes how that fluid column behaves changes the displayed waveform. The Joffe authors list air bubbles, clots and excessive tubing as possible mechanical causes of poor damping, though they did not examine them in their study. FDA’s description of the continuous flush device lists waveform damping among the problems the flush is meant to prevent.
In that study, 66 arterial line flush tests were assessed: 30 (46%) were optimally damped, 25 (38%) over-damped and 11 (17%) under-damped. This was a pediatric intensive care population and the findings should be read in that context.
Handling basics
Manufacturers’ instructions for use govern each product, and facility policy governs everything else. This page does not give setup or insertion steps.
Common mistakes
- Confusing the dialysis arterial bloodline with the arterial pressure monitoring set; they are different products with different uses.
- Treating a transducer, a flush device and a catheter-tip transducer as one item; FDA classifies them separately.
- Reading one study’s set length or volume as a general specification.
FAQ
What is arterial line tubing?
It is the fluid-filled tubing that connects an arterial catheter to a pressure transducer, so the monitor can display arterial pressure continuously. Transducer tubing, pressure transducer tubing and pressure monitoring tubing are other names for the same part of the set.
Is arterial line tubing the same as dialysis arterial tubing?
No. The dialysis arterial line carries blood from the patient to the dialyzer. See blood tubing for dialysis; the dialysis machine is described in what is a dialysis machine.
How does FDA regulate the parts?
The external transducer (21 CFR 870.2850) and the continuous flush device (21 CFR 870.1210) are each Class II devices, and the catheter-tip transducer is a separate Class II classification (21 CFR 870.2870).
Sources
All sources checked 2026-10-30.
- 21 CFR 870.2850, Extravascular blood pressure transducer: https://www.law.cornell.edu/cfr/text/21/870.2850
- 21 CFR 870.1210, Continuous flush catheter: https://www.law.cornell.edu/cfr/text/21/870.1210
- openFDA device classification database, product codes DRS, KRA and DXO: https://api.fda.gov/device/classification.json
- Joffe R et al. The accuracy of blood pressure measured by arterial line and non-invasive cuff in critically ill children. Critical Care 2016;20:177. https://pmc.ncbi.nlm.nih.gov/articles/PMC4897864/ (CC BY 4.0)
