A Peripherally Inserted Central Catheter (PICC) is a tube inserted into a vein in the upper arm and threaded into a large central vein near the heart. This device provides long-term access for administering medications, nutrition, fluids, or for drawing blood. Maintaining the PICC line requires diligent care, and the most frequent part of this maintenance is routine flushing. Adherence to a strict schedule and correct technique ensures the line remains safe and effective throughout treatment.
The Purpose of Flushing
Flushing a PICC line is performed primarily to maintain patency, keeping the internal passage of the catheter open and unobstructed. The catheter’s small diameter makes it susceptible to blockages, which can render the line unusable. The main goal of flushing is to prevent the buildup of fibrin, blood cells, and medication residue inside the catheter lumen.
Blood clots are a common threat, as blood can reflux back into the catheter tip when the line is not in use. Injecting a flush solution, typically sterile normal saline, mechanically clears the line of material that could lead to an occlusion. This action also prevents the mixing of incompatible medications administered sequentially. Maintaining a clean internal surface also reduces the risk of bacterial attachment and growth, contributing to a lower risk of infection.
Standard Flushing Schedules
The frequency of flushing depends on whether the line is active or idle. When the line is active, it must be flushed immediately before and after administering any medication, drawing blood, or infusing fluids. This step removes lingering substances and prevents residue or blood from clotting within the lumen.
For idle lines, the required frequency is typically daily or weekly, depending on the protocol and solution used. Many guidelines recommend flushing an idle PICC line with 10 milliliters of normal saline every 12 to 24 hours to maintain patency. If a heparin lock solution is used in addition to saline, the frequency may sometimes be extended to once weekly. The choice between saline-only or saline followed by a heparin lock depends on individual patient factors and institutional guidelines.
The Step-by-Step Flushing Procedure
The flushing procedure involves careful preparation and a specific injection technique to maximize effectiveness. The procedure begins with rigorous hand hygiene and cleaning the needleless connector, or hub, with an antiseptic wipe for at least 15 seconds to reduce the risk of infection. A syringe containing the flush solution, usually 10 milliliters of normal saline, is then attached to the cleaned hub. Using a syringe smaller than 10 milliliters should be avoided, as it can generate excessive pressure capable of damaging the catheter wall.
The solution is injected using the “push-pause” method, which involves injecting small bursts of fluid, approximately 1 milliliter, followed by a brief pause. This pulsatile action creates turbulence within the catheter, which is more effective than a continuous flow at dislodging debris and cleaning the inner walls. The entire volume of the flush is administered without applying force if resistance is encountered.
The final step involves the positive pressure technique, where the line is clamped while the last 0.5 to 1 milliliter of solution is being injected. This technique prevents blood from flowing back into the catheter tip as the syringe is removed, which reduces the risk of a blood clot forming.
Identifying and Preventing Complications
Consistent and timely flushing is the best defense against PICC line complications. Patients and caregivers should be aware of warning signs that maintenance may be failing. The most common complication is occlusion, identified by difficulty injecting the flush solution or feeling significant resistance. An inability to draw blood from the line, sluggish flow during an infusion, or an infusion pump frequently alarming are also signs that the catheter’s patency is compromised.
Signs of infection at the insertion site include redness, swelling, or pain and tenderness around the catheter, along with any discharge from the area. Systemic signs of a developing infection can include fever or chills. If any of these signs appear, or if there is swelling in the arm where the line is inserted, a healthcare provider must be contacted immediately. Adhering to the prescribed flushing schedule and using the correct push-pause and positive pressure techniques, along with maintaining strict hand hygiene, are the most effective measures for complication prevention.