A peripherally inserted central catheter (PICC line) is a thin, flexible tube inserted into a vein in the arm. This catheter is guided through the vein until its tip rests in a large central vein near the heart, typically the superior vena cava. The purpose of a PICC line is to provide prolonged access to the bloodstream for treatments such as long-term antibiotics, chemotherapy, or specialized nutrition. The safety and function of the line depend on its tip remaining in the correct position. Movement of the external portion is a serious concern, as it indicates the internal tip location may have shifted, potentially compromising the therapy or patient safety.
Measuring and Monitoring External Line Length
Monitoring the internal position of a PICC line is done by tracking the length of the catheter outside the insertion site. At insertion, the healthcare provider records this external length as a baseline measurement. The catheter is often marked with centimeter “tic-marks” for measurement against the securement device or the skin insertion point. A change in external length signals that the internal tip has migrated and should be treated seriously. Movement exceeding one centimeter requires immediate clinical review, as a line pulled out by several centimeters may lose its central line status, affecting the type of medication that can be safely infused.
Common Causes of PICC Line Migration
Catheter movement can be triggered by both mechanical forces applied externally and physiological changes.
External Mechanical Causes
The most frequent cause of migration is accidental pulling or tugging on the line during routine activities like bathing, dressing, or sleeping. Inadequate securement of the external catheter or a loose dressing also increases the risk of dislodgement. Movement of the arm with the PICC line, especially frequent or vigorous flexing of the elbow, can push the catheter in or pull it out at the insertion site.
Internal Physiological Causes
Internal body pressure changes can also cause the tip to shift inside the vein. Actions such as forceful coughing, vomiting, or heavy lifting create pressure fluctuations that move the line’s tip away from its intended position. These internal shifts may not always be visible as a change in the external length, but they still compromise the line’s function.
Immediate Steps If Movement is Noticed
If any change in the external length of the PICC line is observed, or if the initial measurement cannot be confirmed, all infusions must be stopped immediately. Continued use of a dislodged line can lead to severe complications. Do not attempt to push any exposed portion of the catheter back into the insertion site, as this introduces a risk of infection by pushing bacteria from the skin surface into the bloodstream. The site should be gently covered with sterile gauze and the line secured with tape to its current position to prevent accidental traction. The healthcare provider, home care nurse, or emergency services must be contacted right away. Clearly communicate the observed change in length and the time it was noticed. The line should not be used again until its tip position has been verified, usually through an X-ray or other imaging study.
Risks Associated with Significant Dislodgement
Significant dislodgement poses two threats: the line pulling out and the line migrating in.
Migration Outward
If the catheter pulls out too far, it may no longer reach the large central vein, losing its central access status. This change requires the discontinuation of certain medications and increases the risk of phlebitis, or vein irritation, if those medications are continued. If a section of the catheter that was previously beneath the skin is exposed, the risk of infection increases as the sterile barrier is breached.
Migration Inward
If the line migrates inward, advancing closer to the heart, it poses a danger. If the tip enters the right side of the heart, it can irritate the cardiac tissue, potentially leading to cardiac arrhythmia. In rare, severe cases, inward migration can result in cardiac perforation or tamponade, which is a life-threatening emergency. Immediate verification and correction of any observed line migration is necessary.