Technology

Question 1

How big is 1Fr

Answer 1

Divide the Fr number by 3 = the size in mm

3Fr = about 1mm

Question 2

What are ureteric stents made of

Answer 2

Usually silicon, or polyurethrane

Rarely metal = Such as Resonance stent, which is wire based

Question 3

Components of rigid cystoscope

Answer 3

External sheath with obturator
(A resectoscope has additional external/internal sheath to allow inflow and outflow)

Bridge (optional)

Telescope lens/optical system

Light source

Question 4

Common sizes for rigid scope

Answer 4

Usually 15-25Fr

Question 5

Common sizes for ureteroscope

Answer 5

Usually 7-12Fr

Question 6

Common sizes flexual ureteroscopes (fURS)

Answer 6

6-9Fr

Question 7

Key characteristics that allow a laser to work well

Answer 7

The light needs to be = Monochromatic, coherent, and collimated

So can travel down fibre and have desired clinical effect

Question 8

Coating in ureteric stent that makes it radiopaque

Answer 8

Barium sulfate

Question 9

Main components of laparoscopic cart

Answer 9

Insufflator
Light source
Camera controls
Recording device

Question 10

Steps for veress needle pneumoperitoneum

Answer 10

1)Insert needle
-Should feel 2 points of resistance = Abdominal fascia and peritoneum
2) Aspirate to check for blood/bowel contents
3) Flush saline - Should be smooth without resistance
4) Aspirate syringe again - Should be negative again
5) Drop test - remove needle and look at fluid in hub of veress needle
-Should drop down swiftly into peritoneum
6) Advancement - Then can advance by 1cm
-If really in peritoneum, should be able to advance smoothly. Otherwise might still be in preperitoneal speace
7) If all above okay = Pneumoperitoneum

Question 11

Position for access retroperitoneal lap nephrec

Answer 11

In mid axillary line

Usually just below tip of 12th rib

Question 12

Steps for retroperitoneal access lap nephrec

Answer 12

Skin incision
Incise posterior layer lumbodorsal fascia
-And split muscle fibres
Incise anterior thoracolumbar fascia
Insert finger and palpate belly of psoas (posteriorly)
Place baloon dilators to open up space

Question 13

Structural balloons - max volume?

Answer 13

800mls = 40 pumps of the inflating balloon

Question 14

what is capacitive coupling

Answer 14

Transfer of energy within an electrical network by means of capacitance between circuit nodes

Essentially two conductive elements are seperated by an insulator
-Then energy stored producing electrostatic field
-Then net charge exceeds insulators capacity = Causing current transfer between first and second conductor

Classic example = First electrode is active instrument, insulator between, then metal trocar around
-Then bowel adjacent to trocar injuried

Question 15

How does ultrasonic advanced energy devices work?

Answer 15

Piezoelectric crystal system - Electrical energy transformed into mechanical vibration at the tip.

These cause cavitation, coagulation and cutting in the targetted tissues.

Question 16

Benefits of ultrasonic energy

Answer 16

There is less thermal damage and charring

-Because workign temp is less then 80C

But remember that jaws can still get hot.

Also no capacitive coupling, and less wmoke

Question 17

Downsides ultrasonic energy

Answer 17

Slower vessel sealing

Jaws become very hot with activation (over 200C compared to bipolar devices 100C).
-So need to wait for it to cool down

Question 18

Name a device that has combined ultrasonic and advanced bipolar energies

Answer 18

Thunderbeat

Question 19

What are the two different types of grip for this needle holder

Answer 19

Top is straight handled

Bottom is pistol type grip

Question 20

Colours of stapler, their size and what they are used for

Answer 20

Gray = 2mm
White = 2.5mm (vascular like renal vein/artery)
Blue = 3.8mm (bowel/bladder)
Green = 4.8mm (bowel/baldder)

Question 21

Power for electrosurgery

Answer 21

Delivers more then 100W

At a voltage of 100 to 5,000 volts

Question 22

Formula for electrosurgery and interpretation

Answer 22

Ohm’s law = Current = Voltage / Resistance

So more tissue resistance means greated voltage required to deliver current

Question 23

How is energy delivered for coagulation in electrosurgery?

Answer 23

Needs to be interrupted approx 30,000 times a second.

This causes short bursns of radiofrequency energy.

Question 24

How is energy delivered for cutting in electrosurgery?

Answer 24

The radiofrequency current is delivered continuously

Question 25

What is fulguration

Answer 25

When electrode is placed about 2-5mm away from tissue Electrical energy forms spark arcs from electrode to tissue to cause desired effect

Question 26

Pacemaker or IDC with monopolar diathermy?

Answer 26

Try to avoid Need to put magnet over it to deactivate it during surgery