Analysis of chest X-ray plain film images of intravenous ports inserted via the superior vena cava

Purposes

The optimal tip position for an intravenous port and the angle between the locking nut and the catheter are still debatable. This study evaluates the use of chest X-ray plain films for screening patients with potential intravenous port complications.

Methods

We reviewed, retrospectively, 1505 patients who had an intravenous port implanted between January 1 and December 31, 2006 at Chang Gung Memorial Hospital, and were followed up until June 30, 2010. Of the 1119 patients with an intravenous port implanted via the superior vena cava (SVC), 279 underwent re-interventions for complications. There were four different types of single lumen port, and entry vessels on the right side were utilized as the predominant entry sites through the vessel cut-down method for catheter cannulation. The anatomic catheter tip was confirmed on the postero-anterior view of plain chest X-ray films. We used the Picture Arching and Communicating System (PACS) (GE, Fairfield, CT, USA) to record the angle and distance in degrees and centimeters, respectively.

Results

The tracheal carina was seen easily on the chest X-ray plain film and the location of the catheter tip and the angle between the locking nut and the catheter were identified. The location of the catheter tip was significantly related to migration (p < 0.0001). The cut-off value of the receiver operating characteristic (ROC) curve for location and migration was 0.68 cm below the carina. The area under the curve (AUC) was 0.8385 and had favorable predictive power.

Conclusion

The ideal position of an intravenous port to avoid migration is 0.68 cm below the carina. For surgeons, a quantified reference may minimize technical errors. Patients with shallow tip location should be followed up regularly and aggressive intervention initiated for any intravenous port malfunction.