Use of sodium hydroxide solution to clear partially occluded vascular access ports

Gradual vascular access port or tunneled central venous catheter occlusion during total parenteral nutrition is a common complication of unknown etiology, usually unresponsive to treatment with urokinase, ethanol, or hydrochloric acid. After establishing safety with regard to catheter materials and efficacy in dissolving the occluding substance in vitro, we treated a total of 13 vascular access ports (10 patients) that had occluded gradually during "three-in-one" total parental nutrition by slow perfusion with 10 to 20 mL of 0.1 mmol/mL sodium hydroxide solution. We found a mean increase in flow (results are flow rates under gravity-dependent vascular access port inlet pressure of 1.5 kPa) from 37 microL/s (95% upper confidence limit, 45 microL/s) to 75 microL/s (95% lower confidence limit, 64 microL/s; p < .001). For normal use, a flow of 50 microL/s is sufficient. There were no side effects. Five vascular access ports remained in excellent function during a follow-up period of 9 months. The others had reocclusions, but the partial reocclusions could be treated successfully.