These catheters are locked off when not in use and must be flushed with heparin after the saline every 8 hours if locked. Tunneled catheters have an entrance site distance from where the catheter enters the vascular system. This gives the body a chance protect the catheter from bacteria by the longer distance to the insertion site. MMC are inserted in x-ray, the cardiac catheterization laboratory, treatment rooms or at the bedside under sterile conditions. The valve stays shut if not in use.
Central catheters can be internal or external.
Internal devices are completely under the skin and require piercing the skin each time the device is accessed. They may require special needles to access them and less frequent flushing. It is important to know the specific needle required to access an implanted port. A port may become damaged if accessed using the wrong equipment. Broviac catheters are used for pediatric patients and sized accordingly.