Page 128 - Clinical Manual of Small Animal Endosurgery

116 Clinical Manual of Small Animal Endosurgery

float on the fluid surface, increasing the risk of iatrogenic damage when
inserting the Veress needle and the primary trocar and cannula. This risk
is minimised by using a threaded cannula and an open technique to
induce pneumoperitoneum.
Haemostasis is of paramount importance in minimally invasive surgery.
Due to magnification, even small haemorrhages obscure the field of view
and are therefore best prevented. Energy-assisted devices are preferred
to dissect through vascular tissue planes.
In the event of haemorrhage, severed vessels are not easy to isolate,
and using pressure to control bleeding can be difficult. After suction,
clamping the tissue with grasping forceps allows temporary control,
and once the vessel is identified, vascular clips, sutures or electrosurgical
devices are used to achieve haemostasis. Persistent haemorrhage may
require conversion to an open procedure.
At the end of the procedure, the abdominal cavity is inspected to rule
out trauma to the viscera, haemorrhage or other complications. Insuf-
flation pressure is best reduced to 4–6 mmHg to inspect ligature sites, as
higher pressure may prevent bleeding (Kolata and Freeman, 1999b). If
there is concern about active bleeding, it may be necessary to irrigate the
site or lavage the abdomen and aspirate the fluid.
The instruments and telescope are then removed, and the pneumoperi-
toneum is evacuated by discontinuing insufflation and opening the valves
of the cannulae. Gentle pressure is applied onto the abdominal wall while
the cannulae are slowly removed. The puncture sites are inspected for
bleeding, then sutured with interrupted sutures on the body wall and
skin. Entry sites for small cannulae (less than 10 mm) require only skin
suture. Finally, a long-acting local anaesthetic such as bupivacaine is
infiltrated at the port sites.
Although it has been demonstrated that laparoscopic procedure are
associated with less postoperative pain and a more rapid recovery (Magne
and Tams, 1999), multimodal analgesia is necessary in the postoperative
period, for as long as required by the individual patient. The patient
needs to be monitored for insurgence of hypotension, as after desuffla-
tion the abdominal pressure decreases, with a consequent drop in vas-
cular resistance. Patients that are haemodynamically stable usually
tolerate hypotension well, but hypovolaemic animals, or those with
cardiocirculatory compromise, may decompensate.

Exploratory laparoscopy and organ biopsy

In many cases, laparoscopic evaluation of intra-abdominal structures
offers many advantages compared to exploratory laparotomy. Enhanced
visualisation and opportunity to obtain reliable tissue samples allow the
surgeon to acquire useful information also in animals with advanced
disease, or in the work-up of challenging medical cases. Gastro- or
enteral feeding tubes can also be inserted during the procedure. The
surgeon can also perform laparoscopy in view of converting it to open