What is the Hickman line for TPN? A guide to total parenteral nutrition

According to the National Institutes of Health, Total Parenteral Nutrition (TPN) is a viable option when oral and enteral feedings are inadequate. For patients requiring TPN long-term, a Hickman line is often the preferred and most reliable access method.

Quick Summary

A Hickman line is a tunneled central venous catheter providing safe, long-term intravenous access for total parenteral nutrition (TPN) when the digestive system cannot function properly.

Key Points

• Long-term Solution: A Hickman line is a durable, tunneled central venous catheter designed for long-term TPN therapy, lasting months to years.

• Infection Control: The subcutaneous tunneling and Dacron cuff provide an effective barrier, significantly lowering the risk of infection compared to other central lines.

• Reduced Needle Sticks: Using a Hickman line eliminates the need for repeated needle insertions into peripheral veins, reducing discomfort for patients requiring frequent treatment.

• Specialized Care: Proper sterile care, including regular dressing changes and flushing, is mandatory to maintain line function and prevent serious complications like bloodstream infections.

• Critical Access: The line provides essential access for delivering the concentrated nutrient solutions of TPN, which are unsuitable for smaller peripheral veins.

• Multiple Uses: Many Hickman lines have multiple lumens, allowing for TPN, medication administration, and blood draws simultaneously.

Understanding Total Parenteral Nutrition (TPN)

Total Parenteral Nutrition (TPN) is a method of feeding that provides all essential nutrients directly into a patient's bloodstream, bypassing the digestive system. This form of nutrition is crucial for individuals with a non-functioning gastrointestinal (GI) tract or those who require complete bowel rest to heal from an illness or surgery. The TPN formula is a customized sterile solution containing carbohydrates, proteins, fats, vitamins, and minerals.

Unlike standard IV drips given into smaller veins, the high concentration and caloric density of a TPN solution require a more robust and direct route into the body's central circulation. This is where a central venous catheter (CVC), such as a Hickman line, becomes essential for long-term therapy. It provides a reliable and consistent path for delivering nutrition without causing damage to the smaller, more fragile peripheral veins.

What is the Hickman line for TPN?

A Hickman line is a specific type of CVC, named after its developer, Robert O. Hickman. It is a soft, flexible, hollow silicone tube that is surgically implanted for long-term intravenous access. What distinguishes it from other central lines is that a portion of the catheter is 'tunneled' under the skin of the chest before entering a large vein near the heart, like the superior vena cava. This tunneling creates a barrier against infection, a significant advantage for patients needing prolonged treatment.

A key feature of the Hickman line is the Dacron cuff located on the part of the catheter that is under the skin. Over time, the body's tissues grow around this cuff, securely anchoring the line and creating a further barrier against infection. Outside the body, the line can have multiple 'lumens' or channels (one to three), each with a cap. This multi-lumen design is particularly beneficial for TPN patients, as it allows for simultaneous administration of different medications or blood draws without interrupting the continuous TPN infusion.

The procedure for Hickman line insertion

Inserting a Hickman line is a sterile procedure performed by a specialist, typically in a hospital setting. The procedure usually takes between 30 to 45 minutes and is done with local anesthesia, though sedation may also be used.

1. Preparation: The area where the line will be inserted, usually on the chest and neck, is cleaned with an antiseptic solution.
2. Venous Access: Guided by ultrasound, a specialist makes a small incision to access a large vein, such as the internal jugular or subclavian vein.
3. Tunneling: A second incision is made on the chest wall. The catheter is then tunneled under the skin from the chest exit site up to the vein insertion site.
4. Placement: The catheter is threaded into the vein until its tip rests in the large vessel just above the heart. X-ray imaging is used to confirm the correct position.
5. Securing the line: The line is stitched at the exit site to hold it in place while the body's tissue grows into the Dacron cuff. A dressing is applied to protect the site.

Living with a Hickman line for TPN

Caring for a Hickman line properly is crucial to prevent complications, especially infection, which can be serious for TPN patients. Patients and caregivers are trained by healthcare professionals on proper line care.

Routine care and maintenance

• Daily Inspection: The patient or caregiver should check the exit site daily for signs of infection, such as redness, swelling, tenderness, or discharge.
• Dressing Changes: The sterile dressing covering the exit site must be changed regularly, typically once a week or whenever it becomes wet, loose, or dirty. Sterile technique is critical during this process.
• Flushing: Each lumen of the line must be flushed with a saline solution regularly, often weekly, to prevent blockages.
• Protecting the Line: The line must be kept dry during bathing and protected from accidental pulls or snags. Patients should avoid swimming and contact sports.

Hickman vs. PICC Line for TPN: A Comparison

When considering a CVC for TPN, a Hickman line is often compared with a PICC (Peripherally Inserted Central Catheter). The best choice depends on the patient's individual needs and expected duration of therapy.

Feature	Hickman Line	PICC Line (for Central TPN)
Insertion Site	Usually chest/neck, with a tunneled path.	Typically inserted in the arm, traveling up to the chest.
Tunneling	Yes, tunneled under the skin for infection barrier.	No, inserted directly and threaded.
Duration	Long-term use, months to years.	Short- to medium-term, weeks to months.
Infection Risk	Lower due to tunneling and cuff.	Higher risk compared to Hickman.
Insertion Procedure	Requires a minor surgical procedure.	Can often be inserted by a nurse in a less invasive procedure.
Mechanical Complications	Lower risk of mechanical issues.	Higher risk of mechanical complications and thrombosis.
Appearance	May be less visible as the line can be taped down.	Portion of catheter is visible and can be more prone to snagging.

Potential risks and complications

While a Hickman line is a very reliable device, risks are associated with its insertion and long-term use. The most serious risk is infection, which can lead to life-threatening sepsis. Other complications include:

• Blood clots: A thrombosis can form in the vein where the catheter is placed.
• Occlusion: The line can become blocked by a blood clot or precipitate from the TPN formula.
• Damage: The line can be cut or cracked, requiring repair or replacement.
• Insertion-related complications: During placement, there is a small risk of arterial puncture, pneumothorax, or cardiac issues.

Recognizing signs of complications

It is important for patients and caregivers to monitor for any signs of an issue. Immediate medical attention is required if any of the following occur:

• Redness, swelling, tenderness, warmth, or drainage around the catheter exit site.
• Fever, chills, or generally feeling unwell.
• Unusual pain in the neck, shoulder, or chest.
• Swelling of the arm, neck, or face on the same side as the line.
• Inability to flush the catheter or administer TPN.
• Catheter breakage or leakage.

Conclusion

A Hickman line is a specialized, tunneled central venous catheter that provides a safe and reliable method for delivering long-term Total Parenteral Nutrition (TPN). Its design, featuring a subcutaneous tunnel and a cuff, helps minimize the risk of infection compared to other central lines. While insertion requires a surgical procedure, a Hickman line avoids repeated needle sticks, offering a higher quality of life for patients. Proper sterile care and diligent monitoring are essential to prevent complications such as infection and blockage. The choice to use a Hickman line is made in consultation with a medical team, considering the patient's nutritional needs and duration of therapy.

For more in-depth information on managing central lines, you may consult resources from institutions like the National Institutes of Health.

Frequently Asked Questions

What is the difference between a Hickman line and a PICC line for TPN?

A Hickman line is a tunneled CVC typically placed in the chest for long-term use. A PICC line is inserted in the arm and is suitable for shorter to medium-term TPN. Hickman lines generally have a lower risk of infection due to the tunneled path.

How is a Hickman line inserted for TPN?

The line is inserted in a sterile procedure using local anesthesia. A doctor accesses a large vein in the neck or chest, tunnels the catheter under the skin, and guides the tip into a central vein. X-rays confirm correct placement.

What are the signs of a Hickman line infection?

Signs of an infection include redness, swelling, pain, warmth, or drainage at the exit site. Systemic symptoms like fever, chills, or feeling generally unwell also require immediate medical attention.

Can I still shower or bathe with a Hickman line?

You can shower if you protect the line and dressing with a waterproof cover to keep the site dry. Swimming and soaking in a bath are strongly advised against due to the risk of infection.

How often does a Hickman line need to be flushed?

To prevent blockages, each lumen of the Hickman line needs to be flushed on a regular basis, usually once a week or after each use, with a saline solution.

What should I do if my Hickman line gets damaged or leaks?

If the line is damaged or leaks, it should be clamped immediately between the break and the exit site. You should then contact your medical team or go to the emergency department for further instructions.

Is it painful to have a Hickman line inserted?

The insertion procedure uses local anesthesia to numb the area, so you should not feel sharp pain. Some pressure or a stinging sensation from the anesthetic is normal. Soreness or bruising may occur for a few days after.