When it comes to venous catheters, two devices stand out: Midline catheters and PICC Lines. These tools are used to administer medications, solutions, or contrast agents directly into the venous system, but they differ in length, location, duration of use, and risk of complications.
For healthcare professionals and patients, understanding these differences is essential in order to choose the catheter best suited to each situation.
Both types are peripheral venous routes, but Midline catheters, with a maximum length of 20 cm, are inserted into the veins of the arms. In contrast, PICC Lines (Peripherally Inserted Central Catheters) are longer and reach central veins such as the superior vena cava.
In this article, we will examine in detail their specific characteristics, selection criteria, placement and maintenance procedures, as well as their implications for care.
Understand the basics: what is a catheter?
Definition and functioning of catheters
A catheter is a thin, flexible medical device designed to be inserted into a body cavity or blood vessel. Its main purpose is to allow the drainage or perfusion of fluids, such as drugs, solutions, contrast agents or dialysis fluids.
Catheters are used for a variety of treatments and procedures, including intravenous drug administration, parenteral nutrition, blood and platelet administration, and blood sampling for analysis. They are also used to drain excess fluids, such as in the case of ascitic or pleural fluid drainage.
Typologies: Midline vs PICC Line
Among the venous catheters, there are several types, including Midline catheters and PICC Lines, which are among the most commonly used. These two types of catheters are specifically designed for peripheral venous access, but they have significant differences in terms of length, location and duration of use.
Midline catheters and PICC Lines are both inserted into the veins of the arms. However, PICC Lines are longer and reach the central veins, such as the superior vena cava, while Midline catheters remain in the peripheral veins. This difference in location influences their use and the potential complications associated with them.
The specificities of midlines
Advantages of midline catheters
Midline catheters offer several significant advantages that make them particularly useful in certain clinical situations. First, they offer a longer lifespan compared to short peripheral intravenous catheters (SPIVCs), with an average duration ranging from 7.7 to 16.4 days. This characteristic makes them more suitable for mid-term therapies.
In addition, they help reduce major complications, such as bloodstream infections and thromboses, which are often associated with central venous lines. This reduction in complications leads to significant savings in terms of healthcare costs and management of medical problems.
Midlines can also be placed by trained nurses, which accelerates the care process while reducing the workload of physicians. In addition, they are particularly useful for patients with difficult peripheral venous access, as they help preserve venous capital while minimizing repeated venous punctures.
Limitations and risks associated with midlines
Despite their many advantages, Midline catheters present certain limitations and risks. One of the main risks is venous thrombosis, which can occur due to the length and location of the catheter in peripheral veins.
It is also important to monitor for signs of infection or phlebitis, which may develop around the insertion site. Particular attention should be paid to these complications to avoid any negative impact on the patient's health.
The placement of a midline requires the use of an ultrasound and the Seldinger technique, which requires some expertise and specific resources. Although midlines are generally more comfortable than SPIVCs, they can still cause some discomfort and movement restrictions, especially in the arm where they are inserted.
Clinical indications for midlines
Midline catheters are particularly indicated for patients requiring mid-term intravenous therapies, generally over a period of a few days to several weeks. They are ideal for the administration of medications, solutions, and parenteral nutrients, as well as for regular blood sampling, without having to perform repeated venipunctures.
These devices are also recommended for patients with difficult-to-access peripheral veins or those who require preservation of venous capital. Ultrasound-guided midline catheter placement minimizes the risk of venous injury and improves patient comfort.
The Specifics of PICC Lines
Advantages of PICC Lines
PICC Lines (Peripherally Inserted Central Catheters) offer many significant advantages in clinical settings. Their main advantage lies in their ability to administer medications and solutions that may irritate small peripheral veins, while avoiding repeated needle sticks.
This characteristic significantly reduces the risk of phlebitis and other venous complications associated with short peripheral catheters.
PICC Lines are also very practical for regular blood sampling, eliminating the need for frequent venipunctures. In addition, they can remain in place for several weeks or even months, depending on the patient's needs, making them an ideal solution for long-term treatments.
The placement of a PICC Line is relatively less invasive and faster than that of a port-a-cath (PAC) or a percutaneous implantable chamber (CIP). This makes it a particularly attractive option for many patients.
Possible complications of PICC Lines
Despite their many advantages, PICC Lines can entail a number of complications. One of the main ones is the risk of venous thrombosis, which can occur due to the prolonged presence of the catheter in the central veins.
It is essential to monitor for signs of infection, such as phlebitis, endocarditis, or infections at the insertion site.
The placement of a PICC Line must be performed under strictly sterile conditions to minimize the risk of infection. Patients should be monitored carefully for any signs of blood reflux or thrombosis. These risks can be reduced with specific devices, such as the three-way valve of the Groshong® PICC catheter.
In addition, PICC Lines can cause some discomfort and movement restrictions, although these inconveniences are generally minimal. Regular maintenance, including flushing and dressing changes, is essential to prevent these complications.
Clinical indications for PICC Lines
PICC Lines are particularly suitable for patients requiring long-term intravenous treatments, such as chemotherapy, antibiotics, parenteral nutrients, or blood transfusions. They are very useful for patients with fragile or difficult-to-access peripheral veins, as well as for those requiring repeated administration of irritating medications.
These catheters are also recommended for patients in palliative care or long-term care, where the reliability and stability of venous access are essential. Placement under ultrasound or radiological control ensures precise and secure catheter positioning.
Catheter selection: factors to consider
Duration of required venous access
When choosing a venous catheter, the duration of venous access required is a determining factor. Midline catheters are generally indicated for medium-term therapies, ranging from a few days to several weeks, while PICC Lines are more suitable for long-term treatments, which can last from several weeks to several months.
The planned duration of use directly influences the type of catheter chosen. It is essential to select a device capable of supporting the demands of the treatment without requiring frequent replacement. This minimizes the risks associated with repeated insertion and removal procedures.
Type of treatment and infusion frequency
The type of treatment and the frequency of infusions are also essential factors to consider. Irritating drugs or hyperosmolar solutions often require the use of catheters capable of withstanding these substances without causing damage to the veins.
PICC Lines are particularly suitable for these types of treatments due to their insertion into the central veins, where solutions can be diluted more easily.
The frequency of infusions is a key point. Patients requiring frequent or continuous infusions often benefit from the use of a more stable and less invasive catheter, such as PICC Lines or Midlines, which reduce the need for repeated venipunctures.
Patient's venous condition and other medical factors
The patient's venous condition is a determining factor in the choice of catheter. Patients with fragile or difficult-to-access veins may benefit from the use of more flexible and less invasive catheters, such as Midlines.
In contrast, patients with more robust veins can tolerate PICC Lines, which offer long-term stability.
Other medical factors, such as patient autonomy and safety, as well as their position throughout the procedure, should also be considered. For example, patients with reduced mobility or safety concerns may require catheters that are easier to manage and maintain, such as Midlines, which can be placed and maintained by trained nurses.
Placement and maintenance procedures
Insertion: specific techniques for Midlines and PICC Lines
The insertion of Midline and PICC Lines catheters relies on specific techniques that allow for safe and precise placement. For Midline catheters, the procedure generally begins with insertion into a vein in the forearm or arm, just above the elbow, using an ultrasound technique to guide the needle.
The Modified Seldinger Technique (MST) is often preferred for this operation.
In contrast, PICC Lines require a more complex insertion. The procedure begins by applying a tourniquet to the arm to control blood flow, followed by the insertion of a small needle into the vein. A guide wire is then positioned, allowing the catheter to be advanced over this guide wire until it reaches the superior vena cava.
The correct position of the catheter tip is then confirmed by X-ray or ECG.
For both types of catheters, the use of sterile gloves and sterile drapes is essential to ensure a clean environment and reduce the risk of infection. After insertion, the catheter is flushed with a saline solution and then secured to the skin using an adhesive or subcutaneous anchoring system.
Daily care and infection prevention
Daily care and infection prevention are essential for maintaining Midline and PICC lines. Dressings should be changed every 7 to 10 days, or more frequently if the dressing becomes soiled, detached, or shows traces of blood.
Each dressing change must be performed under sterile conditions, using sterile gloves and antiseptic solutions to clean the insertion site.
Flushing the catheter with saline or citrate solution is also essential to prevent thrombosis and obstructions. The push-stop-push technique with positive pressure is often recommended to ensure effective flushing.
Furthermore, regular monitoring of the insertion site is necessary to detect signs of infection, such as redness, pain, or the presence of pus.
Patients should be trained on home care, including catheter handling, dressing changes, and recognition of signs of potential complications. This education is essential to ensure the safety and effectiveness of the treatment.
Implications for healthcare professionals and patients
Training and skills necessary for catheter management
The management of venous catheters, whether Midlines or PICC Lines, requires in-depth training and specific skills for healthcare professionals. Nurses and other practitioners must master the techniques of placement, maintenance, and removal of these devices.
Specialized training is often organized to cover these aspects, including practical workshops on dressing changes, injections, sampling and management of potential complications.
These courses also integrate modules on hand hygiene, surgical scrubbing, and the use of antiseptics to reduce the risk of infection. Participants learn to identify signs of complications, such as infections or thromboses, and to adopt the appropriate course of action in the event of a problem.
Patient involvement and education
Active patient participation and education play a key role in the successful management of venous catheters. Patients should be informed on how to handle their catheter, change dressings, and detect signs of potential complications.
This education includes instructions on catheter flushing, monitoring the insertion site, and maintaining strict hygiene to prevent infections.
Patients should also be made aware of the risks and benefits associated with the use of these devices, which allows them to make informed decisions about their care. Close collaboration between patients and healthcare professionals is essential to ensure effective monitoring and prevent complications, particularly in the context of home care.
Conclusion
In summary, the choice between a Midline catheter and a PICC Line depends on several key factors, including the duration of venous access required, the type of treatment, and the condition of the patient's veins. Midlines are an ideal solution for medium-term therapies, while PICC Lines are better suited for long-term treatments and potentially irritating medications.
The training of healthcare professionals as well as patient education play an essential role in the placement, maintenance, and prevention of complications related to these devices.
It is essential to consider the advantages and limitations of each type of catheter in order to optimize care and reduce risks. By understanding these differences and applying best care practices, healthcare professionals can significantly improve patients' quality of life and treatment outcomes.
We strongly encourage healthcare professionals to integrate this knowledge into their daily practice for optimal management of venous catheters.
FAQ
What is the main difference between the location of the inner extremities of a Midline catheter and a PICC line catheter?
The main difference between the internal ends of a Midline catheter and a PICC line catheter lies in their final position in the venous system. The Midline catheter ends at the axillary or subclavian vein, thus remaining in the peripheral veins. In contrast, the PICC line catheter ends at the junction of the superior vena cava and the right atrium, in the central venous system.
What treatment durations are generally recommended for Midline and PICC line catheters?
Midline catheters are recommended for intravenous treatments lasting three to six weeks. PICC lines, on the other hand, are indicated for more prolonged treatments, lasting up to three months, with the possibility of extension up to six months on medical advice.
What types of medication can be administered via a Midline catheter, and what are the limitations?
Midline catheters allow the administration of drugs compatible with peripheral venous routes, including those with an osmolarity of less than 600 mOsm.l-1, a pH between 5 and 9, and a tonicity between 250 and 350 mEq.l-1. They are appropriate for antibiotics, parenteral nutrition solutions adapted to the peripheral route, and certain non-irritating or non-vesicant drugs.
However, they are not compatible with highly irritating or potentially necrotizing products, which require a central venous access.
Which patients particularly benefit from the use of a Midline catheter versus a PICC line?
Patients who particularly benefit from the use of a Midline catheter are those requiring intravenous therapies for a duration of more than five days, but less than a few weeks. This includes patients receiving drugs and solutions that are generally isotonic and non-irritating, as well as geriatric and pediatric patients who need reliable and less invasive venous access.
