| |
Home > Surgical Tips > Care and Use of Implanted Vascular Catheters in Rats
Care and Use of Implanted Vascular Catheters in Rats
Vascular catheterizations of rats can be utilized for infusion of materials, multiple blood samplings and, in the case of arterial catheterizations, direct blood pressure measurement. Catheters can be filled with viscous heparinized lock solutions such as 50% dextrose or glycerol to extend the patency of the catheter preparations. These catheter lock solutions must be removed before administration of materials via the catheter. The vascular catheter accessory, 23-PP, is a wire plug used to seal the external port of the catheter when it is not in use. The vascular catheter accessory, 23-LH, is a blunted luer hub; which when used in conjunction with a hypodermic syringe; allows access to the circulatory system for catheter flushing, blood sampling, or material infusion.
The materials needed for flushing and use of the implanted vascular catheter preparation are:
A. 23-LH attached to 1 ml hypodermic syringe, several of these units may be needed
B. A catheter flush solution such as phosphate buffered saline
C. A heparinized catheter fill/lock solution
All materials should be sterilized before use.
A simplified protocol for the flushing and use of the implanted catheter preparation is as follows:
1. Remove the 23-PP and replace with a 23-LH attached to 1 ml hypodermic syringe. The syringe assembly should contain a small amount of flush solution. Please note that this must be performed rapidly for arterial catheter preparations and applying hemostatic forceps to the exposed portion of the catheter port may be helpful but care must be taken to avoid damage to the catheter port.
2. Gently withdraw the syringe plunger until blood is seen in the hypodermic syringe. This sample will contain the catheter fill solution mixed with blood and should be discarded. A second 23-LH attached to an empty 1 ml hypodermic syringe can now be used to obtain experimental blood sample. If resistance is encountered, gently apply positive pressure to the syringe plunger, and then withdraw.
3. A 23-LH/syringe assembly containing 0.2 ml of flush solution should be connected to the catheter port and the contents expressed to flush blood from the catheter. Material injections or infusions can now be performed.
4. A 23-LH/syringe assembly containing 0.05 ml of fill solution should be connected to the catheter port and the contents expressed to fill the catheter with lock solution. The assembly is then removed and replaced with the 23-PP to seal the catheter.
Catheters should be flushed on a routine schedule of 1 to 3 times per week.
|
|