From the Guidelines
To clear an occluded midline intravenous (IV) catheter, the primary recommendation is to attempt a gentle flush with 0.9% normal saline using a 10 mL syringe, as suggested by the most recent and highest quality study 1. This approach is based on the principle of minimizing damage to the catheter while attempting to restore patency. The study published in 2021 in the Clinical Nutrition journal suggests irrigation of the catheter with saline as the first attempt to restore catheter patency in intra-lumen catheter occlusion, with a low grade of evidence but recent publication.
Key Steps for Clearing the Catheter
- Assess the catheter for any external damage or displacement before attempting to clear it.
- Clean the access port with an alcohol swab and attach the saline-filled syringe.
- Apply steady, gentle pressure while attempting to flush, avoiding excessive force.
- If resistance continues, try the "push-pause" technique by administering small 1-2 mL pulses of saline with brief pauses between attempts.
- Never use smaller syringes (less than 10 mL) as they generate higher pressure that could damage the catheter.
Considerations for Thrombotic Occlusion
If the occlusion is suspected to be thrombotic, the use of fibrinolytic drugs such as alteplase is recommended, as supported by studies like 1, which discusses the efficacy of alteplase in treating thrombotic catheter occlusions. However, the choice of thrombolytic agent and the protocol for its use should be guided by institutional policies and the specific circumstances of the patient.
Importance of Gentle Technique
Forceful flushing should always be avoided as it risks catheter rupture or embolization of the obstruction. If the catheter remains occluded despite these measures, it may require removal and replacement by qualified personnel. The goal is to restore catheter function while minimizing the risk of complications, prioritizing the patient's morbidity, mortality, and quality of life outcomes.
From the FDA Drug Label
DOSAGE AND ADMINISTRATION Cathflo® Activase® (Alteplase) is for instillation into the dysfunctional catheter at a concentration of 1 mg/mL If catheter function is not restored at 120 minutes after 1 dose of Cathflo Activase, a second dose may be instilled Instill the appropriate dose of Cathflo Activase into the occluded catheter. After 30 minutes of dwell time, assess catheter function by attempting to aspirate blood If the catheter is not functional, go to Step 5. After 120 minutes of dwell time, assess catheter function by attempting to aspirate blood and catheter contents.
The recommended dose for clearing an occluded midline intravenous (IV) catheter is 2 mg in 2 mL for patients weighing ≥30 kg, and 110% of the internal lumen volume of the catheter, not to exceed 2 mg in 2 mL for patients weighing <30 kg. If catheter function is not restored after one dose, a second dose of equal amount may be instilled. The catheter function should be assessed after 30 minutes and 120 minutes of dwell time by attempting to aspirate blood and catheter contents 2 2.
From the Research
Recommendations for Clearing an Occluded Midline Intravenous (IV) Catheter
- The use of tissue plasminogen activator (t-PA) has been investigated for occluded central venous catheters, with studies suggesting it may be a safe and effective thrombolytic agent 3.
- A study found that 5 out of 6 catheters that failed to clear with urokinase were successfully cleared with t-PA, with no coagulation abnormalities or bleeding observed 3.
- The dosage used in the study was 2 mg/2 cc of t-PA, with a mean of 1.5 bolus installations 3.
- Another study used recombinant tissue plasminogen activator (rt-PA) for segmentally enclosed thrombolysis in percutaneous transluminal angioplasty for femoropopliteal occlusions, with promising results 4.
- However, it is essential to note that the use of t-PA for occluded midline IV catheters is not directly addressed in the provided studies, and more research may be needed to confirm its effectiveness and safety in this specific context.
- Flushing vascular access devices before each infusion is crucial to assess catheter function and prevent catheter-related complications, as emphasized in current guidelines 5.