electricity and lasers

current

measured in amps

flow of electrons

poles

opposite charged ends of magnet

circuit 4 requirements, PCLS

source of power, conductor,load,switch

voltage

electrical charge

power

masured in watts

rate in work done

load uses

device that uses electricity

switch

device used to open/close circuit

what does amps measure

current

what does watts measure

power

conductors

allow free flow of electrons

COPPER

resistance

restricting flow of current

insulators

inhibit flow of electrons

current

flow of electrons/ electric charge

1st prong

positive

2nd

negative

3rd

ground- seeks electrical current- never cut

direct current DC

current flows in one direction from - to +

DC 4 loads SCCL

source, conductors, control, load

alternating Current AC

flow of current that reverses direction

frequency

cycles per second

60 AC cycle

transformers

devices that reduce/increase exit voltage

radiofrequency waves

electromagnetic waves

system in OR

isolated power

isolated power

monitors power/fires/currents

active electrode aka as

bovie pencil

ESU developed

1926- William T Bovie

electrosurgery is

AC application to coagulate/cut

monopolar

used for cut/ coagulate

bipolar

only for coagulation No cutting

grounding pad used for

monopolar

argon plasma coagulation does what

enhance effect on ESU, less tissue damage in airways

causes for surgical team burns

RF capacitive coupling

dieleric breakdown

high voltages breakdown insulating material

3 alternative energies

harmonic scapel, plasma vapor, lasers

harmonic scapel

ultrasonic energy/ mechanical vibrations

cut and coagulate

less thermal damage

plasma vaporization

ablation- vaporize tissue without contact

used in bladder

CUSA

high frequency sound waves to emulsify tumors

laser light is of what

monochromatic, all same color and wavelength

wavelength

color determines reaction w/ tissues

collimated waves

waves are parallel to laser light

diverge

travel away from source

coherent

collimated light waves travel in same direction

fluence unit measure

energy per unit CM2

jolue

measure of laser pulse energy

fluence emphizises

highest wattage for shortest time

4 interactions of laser ATRS

absorb, transmission, reflection, scattering

absorption

thermal damage by fluence and wavelength

transmission

passage of laser through tissue

reflection/scattering

hitting non target sites but reflecting off site/insturments

what is a laser named for

active medium

what are the 3 laser units

console, cooling system, vacuum pump

carbon dioxide CO2 laser

(ablation laser)

invisible beam- HeNe combo for read beam to help aim- mirrors

dermatological indications

diode laser

soft tissue ablation in dental

ND: YAG

alternating wavelength passing thru crystal phosphate, invisible/ clear fluid

used in eyes

tips heat if no tissue contact- tips can cool down

HO: YAG

invisible, HENE aiming beam, transmitted thru clear fluids

erbium yag

used for skin resurfacing,

krypton

gas laser electrical current activates krypton- destroy retina

argon laser

no aim beam

plasma tube travels to argon atoms to provide laser energy

coag/ vapor thru clear fluids