Specialized Access as Parenteral Routes

Specialized Access as Parenteral Routes

  • When it is necessary to administer repeated injections over time, it is prudent to employ specialized devices that provide continued access and reduce pain associated with administration.

  • A central component in modern medical care, several types of central venous catheters are widely used in institutions and outpatient settings for a variety of parenteral medications such as cancer chemotherapy, long-term antibiotic therapy, and total parenteral nutrition (TPN) solutions.

  • These central venous catheters can remain in place for varying durations, from a few days to several months, depending on the patient's treatment needs.

  • To maintain the patency of the catheter lumen when not in use, they require heparinization, which involves flushing the catheter with a heparin solution to prevent clot formation.

  • The use of indwelling plastic catheters significantly reduces the need for multiple punctures during intravenous (IV) therapy, thus improving the patient's comfort and outcomes.

  • These catheters are typically composed of materials such as polyvinyl chloride (PVC), Teflon, and polyethylene and should be radiopaque to ensure visibility on radiographs.

  • Different types of catheters are available based on their design and intended use, including:

    1. Plain Plastic Catheters: Basic design suitable for short-term use.

    2. Catheter Over Needle/Outside Needle: Provides a different method of insertion, often for easier access and removal.

    3. Catheter Inside Needle: Used for specific procedures where precise placement is needed.

  • The injection ports on Broviac and Hickman central vein catheters are unique in that they are not implanted subdermally.

  • Instead, they are positioned externally, usually at the abdomen, after the catheter has been tunneled under the abdominal skin and chest to connect to the superior vena cava.

  • While these devices are designed to facilitate repeated access to the infusion site, they carry risks of morbidity, including catheter fractures, entrance site infections, and catheter-associated sepsis.

  • In response to complications associated with cannulation, newer models have been developed to offer safer alternatives.

  • These devices can provide repeated access to various infusion sites, including veins, cavities, arteries, or even the central nervous system.

  • A specialized Huber point needle is utilized to inject through the skin into the rubber septum of a totally implanted central vein access device, ensuring a secure and effective method for administering medications without frequent needle sticks.