Page 150 - Clinical Manual of Small Animal Endosurgery

138 Clinical Manual of Small Animal Endosurgery

of this risk when giving their consent for laparoscopy. When the initial
examination suggests an involved procedure is warranted, or when tra-
ditional laparoscopy does not provide adequate and safe exposure, the
surgeon may elect to perform conversion to ‘open’ celiotomy. The umbil-
ical port is extended cranially and caudally along the linea alba, retrac-
tors are placed, and the procedure is converted from a laparoscopic to
an open approach.

Anaesthesia and preoperative preparation

Anaesthesia and preoperative preparation proceed in a standard fashion
as if the surgical procedure were going to be performed by open tech-
nique. Additional concerns for anaesthesia include increased abdominal
pressure and absorption of carbon dioxide from pneumoperitoneum.
With increased abdominal pressure there is reduced tidal volume, so
assisted ventilation may be necessary. Carbon dioxide absorption leads
to elevated P a CO 2 , warranting monitoring of pulse oximetry and end-
tidal carbon dioxide (Weil, 2009). Positioning the animal for laparoscopy
is critical to ensure that the procedure proceeds expediently. An operative
table that is capable of being tilted head up or down and to the right or
left simplifies the operative set-up. Having a monitor at both the head
and foot of the table minimises the need to re-arrange the room during
a procedure. It is very important to ensure that the animal is securely
positioned and that it will remain so when the table is tilted. Very large
animals have a tendency to slide down the table when the head is elevated
or when tilted to the side if they are not properly secured.

General operative procedures

A well-trained surgical team is essential for smooth functioning of the
operative procedure. While the animal is being draped the instruments
for laparoscopy are opened and assembled on the back table. As the
camera, light guide cable and insufflation tubing require connections to
the endoscopy tower, a non-sterile operating room assistant trained in
operation and trouble-shooting of the equipment and in capturing video
images is essential. Each procedure usually involves a camera operator,
the surgeon and an assistant to manage the back table of supplies and
equipment. The surgical field is widely draped. After the field drape is
applied and the video connections are made, the camera is white-balanced
and the operation begins.

Access and visualisation
Primary port placement is safely achieved using the open technique for
placement of a blunt-tipped Hasson trocar. A small incision is made