Chapter 15 Electrosurgery and Laser Applications

Question 1

Harmonic Scalpel vs Electrocautery - which does not have electricity transferred through or to the patient?

Answer 1

Harmonic scalpel

Question 2

How does the harmonic ultrasonic scalpel work

Answer 2

High frequency vibrations of the instrument cause an oscillating saw effect and vibration induced heat and coagulation

Question 3

Difference between coagulation and cut setting on electrocautery. (Intermittent vs continuous. Low vs high voltage)

Answer 3

Coagulation - Damped - Intermittent waveforms at a high voltage causing more thermal damage
Cut - undamped - continuous waveforms at a low voltage causing minimal collateral thermal damage

Question 4

How is the best hemostasis achieved with electrosurgery

Answer 4

Non-contact form using cutting in order to create the spark through which the current arcs to the tissue

Question 5

T/F: Harmonic scalpel causes more thermal damage than cutting with electrocautery

Answer 5

False

Question 6

Differences between healing of electrosurgery vs scalpel incision

Answer 6

Surgical time and hemostasis improved with electrosurgery

Increase in histologic scores of wound inflammation and delays in wound healing with electrosurgery compared to scalpel incision

Question 7

T/F: CO2 laser is ideal for arthroscopy because it is very specific

Answer 7

False

Question 8

Most and least depth of penetration by lasers

Answer 8

Most at 1094 nm = Nd:YAG
Least at 193 nm = Excimer

Question 9

What type of light does an argon laser use and how does it work

Answer 9

Blue-green light - highly absorbed by hemoglobin then transformed into heat

Question 10

Excimer laser: MOA, depth, benefit

Answer 10

Disrupt molecular bonds on the surface of tissue without causing water vaporization.

Tissue depth 1mm
Ideal for ophthalmic procedures.