Page 187 - Clinical Manual of Small Animal Endosurgery

Thoracoscopy 175

instruments to morcellate tissue inside the bag. The neck of the bag is
brought through the extraction site, and any samples for histology or
microbiology taken. In the absence of a dedicated endosurgical extrac-
tion bag, the finger cut off a silicon glove can be used for extraction of
samples such as small endoloop lung biopsies. These are not as easy to
manipulate and use. Fingers of latex gloves are less suitable, as they are
weaker and more easily broken, and also have a tendency to stick closed
with moisture when trying to insert a sample.
The extraction-site wound can also be limited when using a rip-proof
bag. The neck of the bag is exteriorised and samples taken for histology
and culture as needed (this may be aided by inserting the endoscope
into the bag; however, the endoscope should not then be re-inserted into
the chest without adequate cleaning; an alternative is to use a different
smaller endoscope for this purpose). After this, sponge-holding forceps
are inserted into the neck of the bag and used to mash the tissue, which
can then be removed piecemeal via the bag’s neck, or alternatively it will
simply allow removal via a smaller wound as the tissue is less rigid. This
procedure unfortunately is not as effective with lungs, especially if fibro-
sis is present, as it is with liver. Scissors should not be inserted into the
bag in an effort to cut the tissue, as this could result in cutting the bag
with subsequent leakage of contents into the chest.

Staplers
Endosurgical stapling equipment is among the most expensive single-use
consumable items that a veterinary surgeon may consider purchasing.
Less costly extracorporeal ligatures are more suited to some veterinary
thoracoscopic procedures. Endosurgical staplers produce two to three
lines of staples on either side of tissue, as well as cutting between these
staple lines. Different staple cartridge lengths (30, 45 and 60 mm) and
different staple sizes (2.0–4.8 mm) are suited to different tissue thick-
nesses and procedures. As a rough guide, a 2.0 or 2.5 mm staple leg
length is generally suitable for most peripheral lung, while partial or
complete lobectomies in medium and larger dogs usually require a
3.5 mm staple leg length. Endosurgical staplers with 2.0–3.5 mm staples
suited to thoracoscopy need a 12 mm port for insertion.
Of current endosurgical staplers the Endo GIA universal stapler (Covi-
dien) is the best suited to veterinary thoracoscopic surgical use. The
universal handpiece can be reused with care a reasonable number of
times and re-sterilised with ethylene oxide. Straight and articulated
(called Roticulator) cartridges of differing length and different staple
sizes can all be used with the same universal handpiece. Each individual
staple cartridge contains its own anvil and blade. While Ethicon endo-
surgery ETS staplers provide a better-quality sturdy steel anvil as part of
the handpiece, and are hence favoured by many colorectal surgeons
working with humans, they are not as suitable for veterinary thoraco-
scopic use. The main disadvantage for veterinary surgeons is that despite