The causes of catheter occlusion might be thrombotic, related to drug or parenteral nutrition (PN) precipitates or mechanical. Still, the most effective locking solution will depend on the catheter type and the patient's condition.įlushing and locking have been strongly associated with the prevention of catheter occlusion. Other catheter lock solutions focus on the anti-infective properties of the locks such as antibiotics and chelating agents. Thrombolytic agents have also been studied as a locking solution because their antithrombotic effect was suggested as superior to heparin. More recently, a 0.9% sodium chloride lock has also been investigated in other types of catheters.

A long time ago, 0.9% sodium chloride was already introduced as locking solution in peripheral cannulas. However, the high number of risks associated with heparin forces us to look for alternatives.

Heparin has played a key role in locking venous catheters. For years, it has been thought that the catheter has to be filled with an anticoagulant to prevent catheter occlusion. If a catheter is not in use, it is locked. Therefore fluid dynamics, flushing techniques, and sufficient flushing volumes are important matters in adequate flushing in all catheter types.

The clinical sign of an occlusion is catheter malfunction and flushing is strongly recommended to ensure a well-functioning catheter. Flushing and locking of intravenous catheters are thought to be essential in the prevention of occlusion.

Dead space in 0.5 animal syringe