Spontaneous fracture of implanted central venous catheters in cancer patients: report of two cases and retrospective analysis of the 'pinch-off sign' as a risk factor.

Spontaneous fracture of central venous catheters (CVC) has been reported. It results from repeated compression of the extravasal part of the CVC between the clavicle and the first rib. The so called pinch-off sign (POS) of the CVC as visible on a chest radiograph has been described as a warning for this complication. Fracture of CVC in patients receiving chemotherapy results in extravasation of the drug which may have serious consequences. We describe the spontaneous fracture of a CVC in two cancer patients. Subsequently we retrospectively analyzed chest radiographs for the POS of 77 cancer patients who received chemotherapy through a CVC and correlated these results with the occurence of complications related to CVC compression. In 77 patients a total of 97 CVC were implanted for a median duration of 7 months. Four CVC (4%) showed a grade 2 POS (change in course of CVC)CVC with luminal narrowing) on a chest radiograph. In three of these (75%) a compression-related complication occurred versus no compression-related complications in 93 CVC showing a POS of grade 1 (change in course of CVC without narrowing) or 0 (no change in course of CVC). The grade of POS on a chest radiograph may vary with the position of the patient, but all grade 2 POS were visible in the upright position. We recommend a chest radiograph in the upright position after placement of a CVC for grading of the POS. CVC showing a grade 2 POS should be removed or at least checked by a chest radiograph before the start of each chemotherapy infusion.(ABSTRACT TRUNCATED AT 250 WORDS)