To the best of our knowledge, this is the first case of catheter fracture occurring during femoral placement of TIVAP. Several retrospective studies reported that femoral placement of a TIVAP was feasible in view of the high technical success rate as well as low early and late complication rates (Almasi-Sperling et al. 2016; Bertoglio et al. 1996; Chen et al. 2008; Goltz et al. 2014; Kato et al. 2016; Wolosker et al. 2004). Even in cases of late complications, infection, catheter occlusion, and blood clots were reported, but not catheter fracture (Almasi-Sperling et al. 2016; Bertoglio et al. 1996; Chen et al. 2008; Goltz et al. 2014; Kato et al. 2016; Wolosker et al. 2004). However, as the catheter fracture in the femoral position has not been previously reported, the reasons why catheter fracture occurred in the femoral placement are unclear.
Then, we consider three plausible reasons contributed to catheter fracture in the femoral vein. The first possibility was that chronic stress caused by motion of the hip joint and thigh. The most common cause of catheter fracture in the standard position is “pinch-off syndrome”. This syndrome occurs when the catheter is compressed between the first rib and the clavicle (Kurul et al. 2002). In the present case, the fractured catheter’s edges were rounded and polished due to repeated material wear, with part of the circumference of the break manifesting a rough/granular texture. These findings indicated that this flexural fatigue damage might result in a complete break. Furthermore, the overall elliptical shape of the fracture cross-section indicated repeated kinking of the tubing.
The second possibility was that silicone catheters are more prone to fracture. A retrospective analysis of 698 consecutively implanted TIVAP at the forearm indicated that fracture of the catheter was observed in 3/302 (1.0%) cases in which a silicone catheter was used, whereas no rupture occurred when a polyurethane catheter was used (Wildgruber et al. 2016). Moreover, in patients with implanted TIVAP at the IJV, Groshong silicone catheters were reported as a potential risk for catheter fracture (Saijo et al., n.d.). Power-injectable Groshong silicone TIVAP could be attributed to the fracture in our case.
The final possibility was ultrasound-guided “out-of-plane” puncture of the femoral vein. We performed “out-of-plane” puncture of the femoral vein, which is reported to be a risk factor for IJV puncture. A retrospective analysis of 338 removed ports reported that out-of-plane” ultrasound-guided puncture of the IJV was significantly associated with catheter ruptures, which is invariably associated with a more vertical pathway and a narrower angle at the entry point into the vein wall (Balsorano et al. 2014).
When the backflow of blood from TIVAP is insufficient, X-ray photography should be considered for early detection of catheter fracture. In the present case, catheter fracture occurred even though injection through TIVAP proceeded smoothly. Contrast-enhanced sodium was injected through TIVAP and sodium flow could be observed in the femoral vein. These atypical findings could be due to a narrow tract between the tip of the fractured catheter and the femoral vein shown by contrast injection (Fig. 2).
In conclusion, we experienced the first case of spontaneous catheter fracture after femoral placement of a TIVAP. This fracture could be explained by chronic stress to the catheter caused by motion and use of silicone catheters and ultrasound-guided “out-of-plane” punctures. Even in cases in which it is possible to injection through TIVAP, catheter fracture should be considered as a possible complication of femoral placement of a TIVAP when the backflow of blood from TIVAP is insufficient. Further investigation is needed to clarify the safety of femoral placement of a TIVAP.