Peritoneal Catheter Length Marks: Why They Matter When Trimming

The DESU peritoneal catheter is a 120 cm radiopaque silicone catheter with a 1.1 mm inner and 2.5 mm outer diameter, tantalum length marks at every centimetre from 5 to 20 cm and drainage holes along four rows at the proximal end. The marks give the surgeon a readable reference when the catheter is shortened and placed, and when its position is later checked on imaging.

The peritoneal catheter kit belongs to DESU’s range of neurosurgical catheters and supplies the outflow end of a shunt. The catheter comes long, and its length marks are useful at the moment the surgeon decides how much of it to use.

What does the peritoneal catheter do in a shunt?

In a ventriculoperitoneal or lumboperitoneal shunt, the peritoneal catheter carries cerebrospinal fluid from the valve to the peritoneal cavity, where it is absorbed. It runs under the skin from the valve to the abdomen, so it is the longest component of the system.

What are the specifications of the DESU peritoneal catheter?

The 2.5 mm outer diameter is the same as that of the DESU ventricular catheter, while the inner diameter is 1.1 mm rather than 1.3 mm. The Defit, Decurve and Depus VP shunt kits use the same peritoneal catheter dimensions.

Why is a peritoneal catheter supplied at 120 cm?

Patients differ widely in height and build, from infants to adults, and the distance from the valve to the abdomen differs with them. Peritoneal catheters are generally supplied longer than most patients need, and the surgeon decides the final length at surgery. Starting long means a single catheter can serve a wide range of patients, and the team does not need to stock several lengths.

The route, the length inside the abdomen, how the catheter is secured, and whether it is shortened, by how much and at which end are surgical decisions that follow the instructions for use.

Why do length marks matter when the catheter is trimmed and placed?

Without marks, the team has to measure a soft, wet silicone tube against a ruler in a sterile field, or estimate. With tantalum marks at every centimetre from 5 to 20 cm, the reading is on the catheter itself.

• A direct reading: the surgeon can see how many centimetres lie beyond a given point within the marked zone, without a separate measuring step.
• Consistency: when the length used is noted against the marks, the next operation, or a revision, starts from a known figure.
• Documentation: the mark observed at a reference point can be written into the operative note, which is more precise than an estimate.
• Imaging: because the marks are tantalum, they appear on X-ray and CT, so the segment of catheter they cover can be identified on later images.
• Communication: theatre staff, radiology and the surgical team can refer to the same numbered reference.

The same principle is discussed for EVD and ventricular catheters in catheter tantalum length marks and radiopacity. On the peritoneal catheter the marked zone is longer, running to 20 cm rather than 15 cm.

Why does radiopaque silicone help after surgery?

The silicone itself is radiopaque, so the catheter’s course from the valve to the abdomen can be followed under imaging. If a shunt is investigated later, a radiopaque catheter with numbered marks makes it easier to see where the catheter runs and to compare the images with what was recorded at surgery. For patients and families, our guide to living with a shunt covers life after shunt surgery in plain language.

How are the drainage holes arranged?

The drainage holes sit at the proximal end, arranged along four rows, which distributes the openings over the drainage section. Any question about the effect of shortening on the drainage section should be checked against the instructions for use before surgery.

Standard or antibiotic-impregnated: what is the difference?

In the antibiotic-impregnated version, the antibiotic is impregnated into the catheter material and released in a controlled manner over 28 days. The dimensions and marks are unchanged, so the trimming and documentation workflow is the same for both. The choice between them is clinical.

Which DESU kits include the 120 cm peritoneal catheter?

• Peritoneal catheter kit: the peritoneal catheter on its own, standard or antibiotic-impregnated.
• Ventriculoperitoneal catheter kit: the 120 cm peritoneal catheter with a 23 cm ventricular catheter, a stylet and a right-angled connector.
• Lumboperitoneal catheter kit: the 120 cm peritoneal catheter with a 100 cm lumbar catheter, a 14 G Tuohy needle and a guidewire.
• Defit, Decurve and Depus VP shunt kits: the same peritoneal catheter, supplied with the valve.

Hospitals that stock separate catheter kits alongside complete shunt kits may find the bundling approach in combining EVD with ventricular and peritoneal catheter kits useful.

Talk to a DESU product specialist

If you need samples, specification sheets or advice on standard and antibiotic-impregnated peritoneal catheters, DESU’s product specialists can help. Write to sales@desu.tr, use the contact page, or request a quote.