Spontaneous knotting of urinary catheters placed with nonindwelling intent: Case series and literature review

Urethral catheters are placed with nonindwelling intent chiefly for clean intermittent catheterization (CIC), imaging, or collection of a urine sample. Catheter knotting can be a troublesome complication, especially when it occurs in children often resulting in interventions under anesthesia in the operating room. Three children (4 years male, 4 years female, and 6 years male) presented with knotted feeding tubes placed for CIC. Details of these and an additional 31 patients are discussed in a short review. Knotting occurred almost exclusively in children (33/34, 97%), was more common in boys (22/34, 65%) and most often involved a feeding tube (27/34, 79%) with knotting in the bladder (28/34, 82%). Insertion length, caliber and stiffness of catheter, technique, and patient factors are important factors. Avoiding excessive insertion and use of an appropriate size of catheter (that is not too small) may reduce the risk. Manipulation alone (12/34, 35%), with guidewire (5/34, 15%), or with dilatation (3/34, 9%) is most often successful and is best accomplished under general anesthesia. Endourology (7/34, 21%), laparoscopy (1/34, 3%), or an incision (5/34, 15%) may be necessary in some patients. Safeguarding urethral integrity is the overarching concern.