Catheter Management

Preparation and Flushing Technique

Before attempting to flush, check for external causes of obstruction, such as kinks in tubing or patient position, to ensure the catheter is truly obstructed, as recommended by the American Journal of Kidney Diseases guidelines 1
Clean the catheter port with antiseptic and attach a sterile syringe filled with normal saline to the catheter port, applying gentle pressure during irrigation using a turbulent flushing technique, as suggested by the American Journal of Kidney Diseases guidelines 1
Use a minimum flush volume of twice the catheter volume to ensure effective flushing, as recommended by Clinical Nutrition guidelines 2
Use a sterile 10 mL (or larger) syringe to avoid excessive pressure that could damage the catheter, as recommended by Clinical Nutrition guidelines 2, 3
Apply gentle pressure during flushing to prevent catheter damage, and use aseptic technique during all catheter manipulations to prevent infection, as suggested by the Clinical Nutrition guideline 3

For blood clots, consider requesting a fibrinolytic agent, such as urokinase or alteplase, which typically requires a dwell time of at least 30 minutes, as recommended by Clinical Nutrition guidelines 2
For lipid aggregates, consider using a 70% ethanol solution, as recommended by Clinical Nutrition guidelines 2
For mineral precipitates, consider using 0.1 N hydrochloric acid, as recommended by Clinical Nutrition guidelines 2
For drug precipitates, treatment depends on pH, with acidic drugs cleared with 0.1 N HCl and basic medications cleared with sodium bicarbonate or 0.1 N sodium hydroxide, as recommended by Clinical Nutrition guidelines 2

Avoid using scissors near the catheter when changing dressings, as recommended by Clinical Nutrition guidelines 2, 3
Do not use organic solvents that could damage silicone or polyurethane catheters, as recommended by Clinical Nutrition guidelines 2, 3
Maintain strict aseptic technique during all catheter manipulations, and monitor for signs of exit site infection or catheter-related bloodstream infection, as suggested by the Annals of Oncology guideline 4
Monitor for complications, including signs of infection, worsening hematuria after manipulation, and bladder spasms or discomfort, in patients with Foley catheters and hematuria, as recommended by the American College of Radiology 5

The primary recommendation is to use sterile 0.9% sodium chloride for routine flushing, as stated by the Clinical Nutrition guideline 3
For open-ended catheters, heparin sodium flush solutions may be used after proper saline flushing for catheters that will remain closed for >8 hours, when recommended by the manufacturer, according to the Clinical Nutrition guideline 3
For close-ended valve catheters, saline only should be used, following the manufacturer's instructions, as recommended by the Clinical Nutrition guideline 3
Flushing frequency depends on catheter type, with the following recommendations:

Catheter Type	Flushing Frequency
Small caliber (≤5 Fr)	Weekly
Large caliber (≥6 Fr)	Every 3-4 weeks
Active use	After each use and after completion of any infusion or blood sampling
Inactive	At regular intervals to maintain patency

If catheter occlusion occurs, management depends on the suspected cause, with options including ethanol clearance for lipid aggregates, urokinase or recombinant tissue plasminogen activator (rTPA) for clots, NaOH or HCl solutions for drug precipitates, and NaHCO₃ for contrast medium, as recommended by the Clinical Nutrition guideline 3
Gross hematuria with clots may require more aggressive irrigation and potentially continuous bladder irrigation, while post-procedural hematuria is usually self-limiting and microscopic hematuria rarely requires catheter irrigation, as recommended by the American College of Radiology 5