Page 369 - Fluid, Electrolyte, and Acid-Base Disorders in Small Animal Practice

Technical Aspects of Fluid Therapy 359

A

B C

D E

Figure 15-3 Catheterization of the cephalic vein with an over-the-needle style catheter. A, The skin has
been clipped widely, the insertion site blocked with a 9:1 lidocaine/bicarbonate mixture, and the skin has been
aseptically prepared as described in the text. An 18-gauge injection needle is used to create a facilitation
incision in the skin. The skin at that site must never be touched. B, The tip of the needle-catheter assembly is
advanced into the skin puncture and proximally, parallel to the long axis of the vein, through the subcutis as far
as practical before entering the vein. The catheter shaft is not allowed to contact the distal limb hair. The
catheter is angled toward the vein and advanced into it. The goal should be to “snag” the outer layer of
the vein with the needle tip. The flow of blood into the clear needle hub depicted here confirms venipuncture.
C, The needle is held stationary, and the catheter is advanced fully to the Luer hub, or as deeply as possible
without crossing a joint. D, The needle is removed, and an injection plug or “T” piece is connected to
the Luer fitting. Any air is aspirated, and the system is purged with heparinized saline. E, The end of a
1-cm-wide (0.4 inch) strip of white porous tape is secured around the catheter hub, and then the remainder
of the tape is wrapped firmly, but loosely, around the limb.

(continued)