Liver biopsy protocol
Surgery will be performed in a squeeze chute or holding stanchion at the dairy
unit. An area of approximately 10 x 15 cm over the 11th and 12th ribs on the right
side of the animal, about 15 cm below the vertebral shelf, is clipped closely and
scrubbed thoroughly with surgical soap. The area is rinsed with additional
surgical soap and clean water. The surgeon scrubs hands and arms with surgical
soap and the puts on disposable sterile gloves. To induce local anesthesia, 3-10 ml
of Lidocaine HCl (2% solution) is injected SQ and IM between the ribs, using a
sterile single-use needle and syringe. After obtaining anesthesia, a small (ca. 2
cm) incision is made through the skin and underlying fascia. Single-use sterile
scalpel blades are used. The liver biopsy is obtained by using a Hughes-type
biopsy trocar (Amer. J. Vet. Res. 23:1111, 1962). The trocar is passed through the
muscle and peritoneum layers, the inner needle is retracted, and the liver located
by palpation. A core of liver is removed by rotating the trocar. Up to three
separate penetrations with the trocar may be performed at each surgery.
Alternately, a Tru-Cut biopsy needle may be used to obtain the biopsies. After
completing the biopsies, pressure is applied with a sterile gauze to stop any
external bleeding, and the incision is closed with 2 to 5 surgical staples. The
surrounding area below the surgical site is cleansed with surgical soap and water
to remove blood, taking care not to rinse on or above the incision area.