Background Placing central venous access devices (CVADs) is essential in the management of critically ill children. Used for the administration of fluids, medicines, total parenteral nutrition or blood products they may, however, also cause thrombotic complications. Purpose To develop and implement a protocol for the prevention and treatment of catheter-related intraluminal thrombosis in a Paediatric Intensive Care Unit (PICU). Materials and Methods A computerised search was carried out on MEDLINE using the medical subject heading ‘central venous catheter’ associated with ‘occlusion’,’ ‘thrombosis’, ‘critically ill patients’ and ‘fibrinolytic’. The protocol development process was guided by the goal of weighing evidence regarding effectiveness, safety and cost. Algorithms were developed in order to reduce the complexity of the protocol, aid comprehension, and facilitate successful implementation. ResultsWith the information gathered, a protocol was drawn up and those recommendations that best suit our environment were included. They were agreed upon by a broad panel of professionals working in the PICU and the Pharmacy Department. Facts to highlight: Prevention of intraluminal catheter thrombosis: Prevention of intraluminal CVAD thrombosis with continuous heparin infusion: To keep intravenous catheters patent for drug administration, haemodynamic monitoring and blood sampling.Prevention of intraluminal CVAD thrombosis with heparin lock solutions: To maintain catheters not being used for the administration of continuous infusion fluids.Prevention of intraluminal CVAD thrombosis with fibrinolytic lock solutions: If prior intraluminal thrombosis has occurred. The fibrinolytic agent used should be the same as that used for thrombosis resolution.Treatment of intraluminal CVAD thrombosisNormal saline: Flush with 5–10 mL. If after 3 attempts the problem is not solved, administration of fibrinolytic therapy is recommended.Urokinase at a concentration of 5,000 U/mL (first line).Alteplase at a concentration of 1 mg/mL (second line). Conclusions Due to the variety of options available for the pharmacotherapeutic management of intraluminal catheter thrombosis, one measure to improve the quality of the treatment and reduce the variability in prescriptions could be to implement a protocol as described. No conflict of interest.