Physical restraint is often necessary in food animal practice to facilitate completion of surgical procedures says David Anderson, DVM, MS, Dipl. ACVS, Kansas State University, speaking at the 2011 83rd Annual Western Veterinary Conference. There are instances where general anesthesia is the more appropriate choice to provide patient control and comfort.
"Ruminants continue to produce a significant amount of saliva while sedated or anesthetized," Anderson says. "It is important when patients will be placed in lateral or dorsal recumbency using chemical restraint or general anesthesia to position the head so that saliva runs out of the mouth rather than pooling back near the larynx whenever possible." Anderson says this can be accomplished simply by placing a pad under the head-neck junction for patients in lateral recumbency so that the opening of the mouth is below the level of the larynx.
Protecting the airway becomes much more challenging in procedures requiring the patient to be placed in dorsal recumbency. Ruminants placed in dorsal recumbency are positioned on a foam pad with the neck and head extending past the edge. "This elevates the body such that the neck can be gently twisted as the head is lowered to the floor or surgery table surface so that the head can be positioned as lateral as possible to enhance saliva egress," Anderson explains. "When the head cannot be positioned to facilitate saliva egress or the procedure is expected to produce a significant amount of blood or other material that could enter the airway, endotracheal intubation should be strongly considered."
Anderson also demonstrated new techniques for nasotracheal intubation of cattle in the field. "Placement of tracheal tubes is intimidating to many veterinarians because of concerns for how to obtain correct placement and the need for specialized equipment such as a laryngoscope," Anderson says. Anderson's technique only requires an appropriately sized tube for nasotracheal intubation making this procedure easy to perform on the farm and greatly facilitating procedures such as umbilical surgery in calves.