L20: Minimally Invasive Surgery (Case)

Question 1

Minimally Invasive Surgery (MIS)

Answer 1

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

Question 2

laparoscopy

Answer 2

endoscopy in the abd

Question 3

thoracoscopy

Answer 3

endoscopy in the thorax

Question 4

Veress needle

Answer 4

a spring-loaded needle used to create pneumoperitoneum for laparoscopic surgery

Question 5

Trocar

Answer 5

Composed of obturator (sharp or blunt) and cannula (smooth or threaded)

Question 6

cannula

Answer 6

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

Question 7

“the tower”

Answer 7

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

Question 8

rule of triangulation

Answer 8

camera closest to you, then instruments, then monitor in a triangle

Question 9

use what size telescope most commonly?

Answer 9

5mm

Question 10

bipolar cautery

Answer 10

-can be used to easily ligate vessels up to 7mm, ovarian pedicle, etc.

Question 11

forceps used

Answer 11

Babcock
Scissor
Kelly

Question 12

methods of sterilization

Answer 12

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)

Question 13

Indications for laparoscopy

Answer 13

• elective procedures: OVE, gastropexy, cryptorchidectomy, biopsy
• client request
• patient morbidity (less pain, hospitalization, medication, infection)
• hospital reputation

Question 14

contraindications of laparoscopy

Answer 14

• inexperienced surgeon or staff
• missing instrumentation (ie. bipolar cautery)
• advanced and exploratory procedures (GI, cholecystectomy, adrenalectomy)

Question 15

physiologic effects of abdominal insufflation***

Answer 15

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

Question 16

sources of pain: Incisions

Answer 16

tissue injury: cutaneous and muscular nerve endings - nociceptors
tx/prevent: limit incision size and number. Give local anesthetic and NSAIDs; block nerve conduction

Question 17

sources of pain: peritoneal CO2

Answer 17

CO2 + H2O = carbonic acid –> acidosis –> chemical irritation of peritoneum
nonhumidified –> dessication of peritoneum
tx/prevent: evacuate residual gas, use humidified gas

Question 18

sources of pain: stretching of diaphragm

Answer 18

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

Question 19

surgical costs –>

Answer 19

anesthesia
instrumentation
procedure
technical

Question 20

hospital costs –>

Answer 20

level of care
duration
medications

Question 21

total costs –>

Answer 21

neuropraxia: phrenic nerves, visceral afferents

Question 22

convert what percent of diagnostic laparoscopic cases to laparotomy?

Answer 22

20%

Question 23

complications of Lap-OVE

Answer 23

• 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!*

Question 24

surgical complications of OVH or OVE

Answer 24

• 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)

Question 25

long-term complications of OVH or OVE

Answer 25

• 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)

Question 26

see graph slide 8***

Answer 26

:)

Question 27

evidence for OVE over OVH

Answer 27

• easier
• fewer complications
• less tissue trauma
• less painful
• faster
• minimally invasive*

Question 28

indications for prophylactic gastropexy

Answer 28

• relative with GDV
• large breed and deep chest
• Great Danes have 40% lifetime risk
• Irish Wolfhound, Standard Poodle

Question 29

surgical options for prophylactic gastropexy

Answer 29

• open
• keyhole
• laparoscopic
• lap-assisted

Question 30

SILS =

Answer 30

single incision laparoscopic surgery

Question 31

complications of lap-gastropexy

Answer 31

• seroma (very common)
• splenic laceration/hemorrhage
• serosal tearing
• loss of insufflation due to enlarged incision
• dropped stomach
• conversion to keyhole technique possible