There are many factors and details that should be addressed to ensure a satisfactory outcome of vascular catheter implantation. It is also necessary to consider the details of specific experiments. The exact nature of implants and their anatomical placement will be influenced by the species used and the purpose of the study; for example, the desired blood sampling route and regimen, the location of infusion, and blood pressure measurement.
It is essential that preliminary in vitro tests are performed to establish that compounds and solvents are compatabile with catheters, including any connecting tubing, infusion pumps and reservoirs.
Particular problems that may be encountered with infusion studies include:
- Absorption of the compound by tubing and other materials.
- Crystallisation of the compound.
- Compounds precipitating out of solution at low flow rates in narrow bore catheters and tubing.
The presence of foreign material within the vascular system and exposure to any eluting coatings from catheters coupled with the compounds used in locking solutions can all give rise to biological or pathological changes that may confound experimental data (e.g. microthrombi may arise and be deposited in the lung during infusion toxicology studies). Access to good background data and well-designed control groups will assist with data interpretation.
Resources and references
- Guiding principles for preparing for and undertaking aseptic surgery: A report by the LASA Education, Training and Ethics section.
- Methods in vascular infusion biotechnology in research with rodents.
- Refining procedures for the administration of substances.
- Removal of blood from laboratory animals and birds.