L20: Minimally Invasive Surgery (Case) Flashcards
Minimally Invasive Surgery (MIS)
any surgery that is less invasive and/or results in less tissue trauma compared to open surgery
- usually performed w/ telescope and camera
- aka band-aid or keyhole surgery
laparoscopy
endoscopy in the abd
thoracoscopy
endoscopy in the thorax
Veress needle
a spring-loaded needle used to create pneumoperitoneum for laparoscopic surgery
Trocar
Composed of obturator (sharp or blunt) and cannula (smooth or threaded)
cannula
outer part of trocar that stays in abdomen once you take trocar out
- smooth or threaded
- threaded screws in, has tighter seal, and has rubber reducer valves for insufflation or no insufflation w/ one way valve
“the tower”
houses light source, video control unit, insufflator (CO2 gas; air would cause embolism or can combust)
-insufflator keeps abdomen distended and controls flow rate and maximum pressure
rule of triangulation
camera closest to you, then instruments, then monitor in a triangle
use what size telescope most commonly?
5mm
bipolar cautery
-can be used to easily ligate vessels up to 7mm, ovarian pedicle, etc.
forceps used
Babcock
Scissor
Kelly
methods of sterilization
1) Gas (ethylene oxide or gas plasma; preferred for scopes, cameras, cables)
2) Steam sterilization (gravity dependent; ok for scopes/cameras/cables but reduces their life)
3) Cold sterilization (2% glutaraldehyde; use to sterilize scopes between procedures)
Indications for laparoscopy
- elective procedures: OVE, gastropexy, cryptorchidectomy, biopsy
- client request
- patient morbidity (less pain, hospitalization, medication, infection)
- hospital reputation
contraindications of laparoscopy
- inexperienced surgeon or staff
- missing instrumentation (ie. bipolar cautery)
- advanced and exploratory procedures (GI, cholecystectomy, adrenalectomy)
physiologic effects of abdominal insufflation***
pressure against diaphragm and vena cava –> dec. thoracic compliance and venous return –> dec. tidal volume, CO –> hypoventilation, hypoxemia, acidemia
SOLUTION: limit intra-abdominal pressure and duration. Dogs: <8mmHg
sources of pain: Incisions
tissue injury: cutaneous and muscular nerve endings - nociceptors
tx/prevent: limit incision size and number. Give local anesthetic and NSAIDs; block nerve conduction
sources of pain: peritoneal CO2
CO2 + H2O = carbonic acid –> acidosis –> chemical irritation of peritoneum
nonhumidified –> dessication of peritoneum
tx/prevent: evacuate residual gas, use humidified gas
sources of pain: stretching of diaphragm
neuropraxia (disorder of the peripheral nervous system in which there is a temporary loss of motor and sensory function due to blockage of nerve conduction)
-can affect phrenic nerves, visceral afferents
tx/prevent: limit insufflation pressure (dogs <8), limit duration of sx
surgical costs –>
anesthesia
instrumentation
procedure
technical
hospital costs –>
level of care
duration
medications
total costs –>
neuropraxia: phrenic nerves, visceral afferents
convert what percent of diagnostic laparoscopic cases to laparotomy?
20%
complications of Lap-OVE
- splenic laceration/hemorrhage (ace makes spleen enlarge)
- pedicle hemorrhage (usually only a problem if using old cautery)
- SC emphysema
- loss of insufflation due to slipped cannula or enlarged incision
- dropped ovary or pedicle
- conversion is NOT a complication!*
surgical complications of OVH or OVE
- post-op hemorrhage or ovarian a, uterine a., or broad ligament
- ureteral ligation
- Ovarian Remnant Syndrome (70% on R side; prevent with better incision location)
long-term complications of OVH or OVE
- uterine neoplasia: 0.03% risk, 0.003% risk malignant; uterine stump leiomyosarcoma just as likely!
- endometritis/pyometra: 15-25% risk by 10yrs. Requires functional ovarian tissue. Disease of luteal phase (diestrus)
see graph slide 8***
:)
evidence for OVE over OVH
- easier
- fewer complications
- less tissue trauma
- less painful
- faster
- minimally invasive*
indications for prophylactic gastropexy
- relative with GDV
- large breed and deep chest
- Great Danes have 40% lifetime risk
- Irish Wolfhound, Standard Poodle
surgical options for prophylactic gastropexy
- open
- keyhole
- laparoscopic
- lap-assisted
SILS =
single incision laparoscopic surgery
complications of lap-gastropexy
- seroma (very common)
- splenic laceration/hemorrhage
- serosal tearing
- loss of insufflation due to enlarged incision
- dropped stomach
- conversion to keyhole technique possible
