Intravenous administration of material can be technically difficult, and use of a restraining device is often required. These should be selected carefully to be an appropriate size for the animal to be injected.
Intravenous Injection in the Rat
Too small a device can result in injuries to the animal, and can interfere with respiratory movements. Too large a restrainer can also result in injury, caused by movements during restraint.
After use, restraining devices should be cleaned thoroughly, to avoid pheromonally-induced stress or cross-infection.
Since small movements of the animal can dislodge a hypodermic needle from the vein, alternative delivery systems may be found useful, especially in the rat. These will be described in more details on a future tutorial on catheter and needle