Page 116 - Clinical Manual of Small Animal Endosurgery

104 Clinical Manual of Small Animal Endosurgery

• Biopsy: oval cup (clamshell) biopsy forceps are the most versatile,
and are commonly used for liver, spleen and lymph node biopsy,
whereas punch biopsy forceps are preferred for biopsy of the pan-
creas. For kidney and deep-tissue biopsy core biopsy needles are
required; for gall bladder aspiration specific long aspiration needles
(or spinal needles) are employed.

• Haemostasis: different methods are available for controlling bleed-
ing: clip application, sutures and use of energy-assisted devices. Vas-
cular clip applicators are available in different sizes, and can be
reusable or disposable. The clip is held in the applicator shaft and
advanced until both tips are around the vessel, and the instrument
is then closed on the tissue. Clamped tissue should fill approxi-
mately three-quarters of the internal diameter of a clip. Pre-tied loop
ligatures are available for pedicles; alternatively, ligatures can be
performed with several knotting techniques (extra- or intracorpor-
eal). Extracorporeal knot-tying requires a ‘knot-pusher’, that allows
to slide the knot tied outside of the body through the cannula and
inside the body, up to the tissue being tied. Laparoscopic needle
holders are instead used for intracorporeal suturing, and dedicated
hook-type scissors are used to cut sutures. Energy-assisted devices
are also commonly used for haemostasis. Electrosurgical units are the
most economical, and therefore the most widespread in veterinary
medicine; alter natives that can be used for careful dissection are diode
and neodymium:yttrium-aluminium-garnet or Nd:YAG lasers and
ultrasonic devices such as the Harmonic Scalpel (Ethicon Endo-
®
Surgery, Europe GmbH, Germany). The recent introduction of
®
a bipolar electrothermal vessel sealer (LigaSure , Valleylab, Tyco
Healthcare UK), able to seal vessels up to 7 mm in diameter, has
allowed a significant reduction in surgery times.

• Tissue removal: endoscopic staplers apply four or six 3–6 cm long
staggered rows of staplers and cut between the middle rows, thus
allowing easy removal of organ sections and anastomosis. Different
cartridges are available (as in open surgery) depending on the thick-
ness of the tissue to be resected. Morcellators cut tissue into smaller
pieces, thus facilitating removal; specimen-retrieval bags are used
to remove infected or neoplastic tissue. Commercially available bags
usually come on a 10 mm applicator; for smaller samples, bags can
be made inexpensively from a sterile surgical glove.

• Irrigation and suction: aspiration/irrigation units are available with
various tips such as Poole or Yankauer; most devices combine suction
and flushing capabilities, and some are also equipped with a monopo-
lar dissection probe. They are designed to carry out suction and
irrigation without significant loss of insufflation.