Ch 24 Laparoscopy and Thoracoscopy Flashcards
What benefits have been shown regarding minimally invasive surgical procedures? (5)
Decrease in pain
More rapid return to normal activity
Lower incidence of incisional infection
Decreased surgical time
Shorter hospitalisation times
What are the basic components of an endoscopy tower? (5)
Monitor
Camera control box
Light source
Insufflators
Data recording devices
What are they typical light sources?
Halogen or xenon
Xenon is preferred - more closely resembles natural light
What pressure of intrathoracic insufflation causes significant cardiorespiratory depression?
3mmHg
Often not required, placement of cannulas forms a pnemothorax and ribs prevent collapse
What are the recommended insufflation pressures in the abdomen of dogs and cats?
Dogs: 8-10mmHg (Can increase to 15 with acceptable cardiorespiratory depression)
Cats: 8mmHg (little increase in working volume above this)
What is the main gas used for insufflation and why?
How does retrograde flow occur?
CO2
- Does not support combustion
- Cheap
- Colourless
- Rapidly excreted
- Highly soluable (unlikely to form gas embolus)
Retrograde flow can occur when the CO2 canister is depleted intra-op and pressure in the body cavity drives air/fluid in a retrograde manner. Can result in damage and cross contamination of next patient
What is the most versatile telescope for use in vet med?
5mm telescope 29cm in length
0 degress is typically used in the abdomen with 30 degree typically used for thorax
What are the benefits of using a cannula?
Atraumatic repeated instrument exchange
Airtight seal for insufflation
What are the disadvantages of reusable cannulas as apposed to single use cannulas
Heavy weight
Can become dull over time
Changing instruments is cumbersome (reduced caps required)
Main benefit is cost reduction
List some options of single-port surgery devices
SILS port (single-incision laparoscopic surgery)
Triport
Gelport
Endocone
Most incorporate 3-5 ports within a single device
What size instruments are typically used? What sizes are available?
Typically use 5mm instrucments in vet med
2, 3 and 10mm also available
What instruments are requires for basic laparoscopic procedures?
What other insrtuments are commonly useful?
Basic Instruments:
- Metzembaums
- Hook (suture) scissors
- Kelly haemostats
- Babcock forceps
- Cup biopsy forceps
Other useful instruments:
- Right angle forceps
- Knot-pusher (extracorporeal knot tying)
- Fan retractors and inflatable retractors
- Laparoscopic needle holders (parrot jaw most common)
What options are there for laparoscopic/thoracoscopic haemostasis? (5)
Haemostatic agents (gelatin sponge, ORC, fibrin glue)
Haemostatic clips (multifier devices available)
Suturing (extracorporeal, intracorporeal)
Electrosurgery (bipolar is safer)
Vessel sealing devices
ligasure and laparoscopy
pressure exerted on tissue when the tissue is crushed in the tips of the device, followed by application of bipolar or ultrasonic energy. This process allows elastin and collagen in the vessel wall to be sealed together permanently.
LigaSure lateral thermal spread ranged from 1.5 to 3.2 mm in one study, with a greater degree of thermal spread seen as vessel size increased
ForceTriad (Covidien-Medtronic) and the Enseal (Ethicon Endo-Surgery). Both devices have tips that are indicated to seal arteries and veins up to 7 mm in diameter.
What is the strongest slip knot for extracorporeal suturing?
4S modified Roeder knot
An easier alternative to creation of these slip knots for ligation of free tissue pedicles is the pretied loop ligature (Endoloop, Ethicon; Surgitie,
What are the options for laparoscopic vessel sealing device?
What size vessels can then be used on?
ForceTriad - up to 7mm (new generation LigaSure
Enseal - up to 7mm
Harmonic system - up to 5mm
When are specimen retrieval bags indicated?
When removing tissue that could be neoplastic or infected through a small port incision
What size is the most common endoscopic stapler and how many staple rows do they produce?
What sizes endoGIA are available?
Most commonly 12mm in diameter (require 12mm cannula) and combine 2 triple rows of staggered staples seperated by a cutting blade.
EndoGIA come in
lengths of 30, 45 and 60mm
staple lengths of 2.0, 2.5, 3.5 and 4.8mm
(Most common 30-60 length with 3.5m staples)
What are the two techniques for gaining access into the abdominal cavity?
**Veress needle technique **-
Has a spring-loaded blunt-tipped obturator. Hanging-drop test will confirm when in peritoneal cavity. Once insufflated, veress needle is removed and a sharp trocar-cannula can be placed
Modified Hasson technique -
A small approach to the linea just caudal to the umbilicus for controlled incision and placement of trocar-cannula. Blunt-tipped trocar used
What is this instrument?
Veress needle
What 2 options are available to gain access to the thoracic cavity?
What is the preferred method of increasing exposure/space in the thoracic cavity?
Gaining access:
- Veress needle
- Cannula without a diaphragm
One-lung ventilation preferred for increasing exposure, insufflation not well tolerated + help avoid iatrogenic trauma to tissues
What techniques can be used to create one-lung ventilation? (3)
Selective intubation
Bronchial blockers
Double-lumen endobronchial intubation
What process limits the physiological effects of V/Q mismatch with 1-lung ventilation?
Hypoxic pulmonary vasoconstriction
significant physiologic changes must be anticipated due to the fact that a significant ventilation-perfusion mismatch occurs because nonventilated lung remains perfused. However, the process of hypoxic pulmonary vasoconstriction will limit perfusion to the nonventilated lung, and studies have shown that no large effect on oxygen delivery in healthy dogs occurs during one-lung ventilation
What procedures have been reported with the use of one-lung ventilation?
Pericardial windows
Subphrenic pericardiectomy
Lung lobectomy
Thymoma excision
Comparison between intracorporeal and extracorporeal
ligations in a laparoscopic ovariectomy model in dogs
Martin 2021
Study design: Prospective randomized experimental study.
Animals: Healthy intact female dogs (n = 18).
No difference was identified between extracorporeal and
intracorporeal ligations of ovarian pedicles.
A systematic review of complications related
to laparoscopic and laparoscopic-assisted procedures
in dogs
Maurin 2020
Study design: Systematic review.
Animals: Client-owned or healthy research dogs
most commonly reported intraoperative and postoperative complications were related to
abdominal entry and portal incisions, respectively. In 53 of 54 non-randomized
studies, high risk of bias was found
The overall quality of evidence was low, limiting direct comparison of complication rates between studies
The most common intraoperative complication was splenic laceration, was most
commonly related to abdominal entry technique
The conversion rate across all
studies ranged from 0% to 30%.
highest conversion rate was
described in a case series of 20 dogs undergoing cholecystectomy
postoperative complications, recorded 192 times in 20 (31.3%) studies and across all organ systems, were wound related and included emphysema, inflammation, infection, swelling, seroma, discharge, and incisional
authors of a recent study evaluated the
prevalence of and risk factors for complications related to three different entry techniques, the modified Hasson, Veress needle, and Ternamian visual entry techniques.81
In that study, complications were five and 28 times higher with modified Hasson (26%) and Veress needle entry (60%) techniques, respectively, compared with Ternamian
visual entry (9%) technique.
more experienced
laparoscopist, proficient and comfortable with
complex laparoscopic procedures, would tolerate more
adverse situations for a longer time before converting to
an open procedure. Other factors such as careful case
selection are also very likely to influence intraoperative
conversion rates.
Paramedian incisional complications after prophylactic
laparoscopy-assisted gastropexy in 411 dogs
Baron 2020
Multi-institutional retrospective study.
Animals: Client-owned dogs (N = 411).
LAG > In either case, a
laparoscope is used to identify the stomach, the stomach is grasped and exteriorized through a right-sided paramedian
incision, and the gastropexy is performed extracorporeally at that location
Paramedian incisional complications were observed in 78 of
411 (19%) dogs. The most common complication was seroma formation, which
occurred in 51 (12.4%) dogs. Surgical site infections were observed in 16 (3.9%)
dogs, and dehiscence or development of excessive scar tissue at the incision
site were each observed in nine (2.2%) dogs
The odds of complications were approximately twice as high in dogs undergoing single port than in dogs undergoing multiport
The high complication rate
associated with paramedian LAG incisions may be a rationale for intracorporeal gastropexy.
Single-Port Laparoscopic Treatment and
Outcome of Dogs with Ovarian Remnant
Syndrome: 13 Cases (2010–2018)
Aaron Percival 2020
retrospectively reviewed
Major intraoperative complications did not occur and conversion to open laparotomy was not
required. In 1 dog, an SPL 1 1 technique was used, in which an additional port was placed cranial
Clinical signs related to estrus
had resolved in 11 of 13 dog
Comparison of outcome in dogs undergoing single-incision
laparoscopic-assisted intestinal surgery and open laparotomy
for simple small intestinal foreign body removal
Otomo 2019
Retrospective study.
Animals: Twenty-eight client-owned dogs
After laparoscopic evaluation, a wound retraction device
(WRD) was inserted. The small intestine was extracorporeally explored, and foreign
body removal was performed. The surgeon’s hand was inserted through the WRD to
palpate portions of the gastrointestinal tract not able to be extracorporeally evaluated
Conversion
from SILAIS to OL occurred in 3/13 cases
was not significantly different from OL in a variety of outcome measures
in this cohort of dogs. Diagnostic imaging including ultrasonography or computed
tomography may improve appropriate case selection for SILAIS for simple
foreign body removal.
A comparison of the rates of
postoperative complications between
dogs undergoing laparoscopic and open
ovariectomy
T. M. Charlesworth 2019
A retrospective study
46 of 106 (44%) dogs undergoing open ovariectomy developed a complication
Thirty-one (20%) of 154 dogs undergoing laparoscopic ovariectomy developed a complication
herniation occurred in none of the
laparoscopic cases.
rates of overall and wound healing complications were lower for the laparascopic
group than the open surgical group in this non-randomised study. Laparoscopy might be considered
preferable for ovariectomy in dogs but confirmation requires a randomised trial
Hybrid single-port laparoscopic cisterna chyli ablation
for the adjunct treatment of chylothorax disease in dogs
Morris 2019
near-infrared imaging of indocyanine green.
Cadaveric and retrospective study.
Animals: Six canine cadavers and 14 client-owned dogs
wound retractor device (WRD) and a single-port device were placed in the
abdominal flank 2–3 cm caudal to the 13th rib.
Successful ML was completed by using ICG in all 6 canine cadavers. A
right- or left-sided single-port laparoscopic CCA was successfully performed in 14 dogs
No intraoperative complications
were reported. Three dogs developed severe chyloabdomen postoperatively,
with 1 dog requiring multiple abdominocenteses.
sternal recumbency allows both a CCA and an intraoperative ML through the same
incision. This procedure may be combined with thoracoscopic thoracic duct ligation
and pericardectomy for the treatment of idiopathic chylothorax in dogs.
