Vascular access: theory and techniques in the small animal emergency patient.

Acquisition of vascular access in the emergent small animal patient is one of the keys to successful management of a population of patients that are often unstable with regard to their major body systems. Venous and intraosseus cannulation allow for the administration of a variety of fluids and potentially life-saving medications. In addition, central venous and arterial access also serve as conduits for atraumatic blood sampling and intravascular pressure monitoring. A thorough knowledge of vascular access theory, the dynamics of fluid flow, vascular anatomy, catheter selection criteria, and placement techniques are critical to the proper and safe use of the vascular access options available today to the small animal clinician.