Chapter 24 Fundamentals of Laparoscopy and Thoracoscopy

Question 1

List two advantages and two disadvantages of MIS

Answer 1

Less pain, faster return to activity

Prolonged surgery time, need for costly equipment

Question 2

Name the three most important compnents of the “tower”

Answer 2

endoscopy tower (A).

The most important components housed on the tower are the camera box (B),

the light source (C), and the

mechanical insufflator (D).

Question 3

What is the quality of endoscopic camera dependent on?

Answer 3

Depends on camera control unit i.e. chip.

One chip fine, three chip better quality 9i.e. one chip for each primary colour)

Question 4

What are the two types of lightsource available?

Which is preferred and why?

What wattage is recommended?

Answer 4

Halogen or xenon.

Xenon preferred as emith high-intensit light

150 - 300 watts recommended

Question 5

What is recommended limit of insufflation in abdo?

Insufflation not usually nec in thorax - above what pressure is cardiorespiratory depression seen

Answer 5

15 mmHg (or anaesthesia chapter says ensure it is below 14 cm H2O = 11 mmHg…).

8-10 mmHg usually adequate

CR depression seen with thoracic insufflation to 3 mm Hg!

Question 6

Why does insufflation line usually contain microporous filter

Answer 6

Prevent particulate matter/bacteria passing from canister –> patient and prevent back-flow of body fluids into canister

Question 7

List 3 properties that make CO2 good gas for insufflation:

Aside from CO2 what gas has been used for insufflation?

Answer 7

• Cheap
• Rapidly diffuses/excreted
• Colourless

But reported to have detrimental effects on cellular, hormaonal and immunologic functions.

Helium. Hypothesised to cause fewer changes to immulogic and cardiorespiratory status

Question 8

What is most common diameter, lenght and angulation of scope used?

Answer 8

5mm, 29cm 30 degree angled

Question 9

List 6 methods for haemostasis in MIS

Answer 9

Haemostatic agents

Haemostatic clips

Extracorporeal suture

Intracororeal suture

Pre-tied ligature loop

Vessel sealing device

Question 10

What size vessel can harmonic ace tip seal?

Answer 10

5 mm

Question 11

What is thermal spread of ligasure?

Answer 11

1.5 - 3.2mm

Question 12

What cannula is necessary for use of endoscopic staplers?

Answer 12

12mm cannula

Question 13

Briefly outline the two types of MIS abdo entry techniques

How is correct entry confirmed with each technique?

Answer 13

Veress needle technique vs Hasson technique

Veress:

• 2 mm skin incision just cranial to umbilicus. Needle introduced (blunt obturator become depressed into needle). once into abdo, blunt obturator springs back out to protect underlying organs.
• Hanging drop with saline to confirm correct entry

Hasson:

• 4mm incision and dissect down to line alba, just caudal to umbilicus. Blunt tipped trocar used to enter abdo.
• Correct entry confirmed by visualisation of falciform fat.

Also if pressure >6mmHg and low flwo of CO2 suggestive of sc placement

Question 14

List 3 methods for performing one lung ventilation:

Answer 14

• Bronchial blockers
• Selective intubation
• Double lumen endobronchial tube