Incidence and Determinants of Port Occlusions in Cancer Outpatients A Prospective Cohort Study

Background: Normal saline is considered a safe alternative for heparin as a locking solution in totally implantable venous access devices. The incidence rate of partial occlusion with the use of normal saline (easy injection, impossible aspiration) is estimated at 4%. Objective: The aim of this study was to investigate determinants of partial occlusions with the use of normal saline solution and the maintenance of positive pressure in the catheter. Methods: We enrolled 218 patients with different solid tumors who underwent pharmacologic treatment through the port with different frequencies: from once every week to at least once every month. The port was flushed with normal saline solution keeping a positive pressure in the catheter. Results: We performed 4111 observations and documented normal port functioning in 99% of observations (n = 4057) and partial occlusions in 1% of observations (n = 54). Partial occlusions were significantly associated with frequency of port flushing (P <.05), chemotherapy (P <.001), and blood sample collection (P <.001). Conclusions: The use of positive pressure in addition to normal saline reduces the incidence rate of partial occlusions. The type of treatment, blood sample collection, and treatment schedule are important determinants of partial occlusions. Implications for Practice: Nurses play a key role in maintaining a functioning port using positive pressure during the flushing techniques. Certain risk factors must be monitored to prevent partial occlusions, and certain patients are more likely to present with port-related problems.