Laser and operating room safety

Laser accidents—they do happen!
LASER AND OPERATING
ROOM SAFETY
Dr. Meenu Chadha
Chief Anaesthetist, Pain Physician and O.T.
Superintendent. Vishesh Hospital

LASER ACCIDENTS....THEY DO
HAPPEN!
Laser light differs from ordinary light in three ways
 Directionality
 Monochromaticity
 Coherence
Lasers can pose more of a hazard than
ordinary light because they can focus a
lot of power onto a small area

LASER TYPES
 CONTINOUS WAVE- Operates with stable beam power
( power remains constant)
 PULSED OR Q- SWITCHED- Where pulse is generated
by the resonant mode of the optical cavity. Power
fluctuates up and down.

LASER CLASSIFICATION
OLD- American- Used before 2002
REVISED- European- from 2007
 Class 1- Safe under all conditions of normal use
 Class 1 M- Safe for all conditions except when passed
through magnifying optics like telescope or microscope
Laser radiation
Do not view directly with optical
instruments
Class I M Laser product

 Class 2- Safe because the blink reflex will limit the
exposure to no more than 0.25 seconds. It only applies to
visible light lasers.
 Class 2 M- Safe because of the blink reflex if not viewed
through optical instruments.
 Class 3 R- Safe if handled carefully , with restricted beam
viewing.
 .
Laser radiation
Do not stare into beam
Class 2 Laser Product
Laser radiation
Do not stare into beam or view directly with optical
instruments
Class 2 M Laser Product
Laser radiation
Avoid direct eye exposure
Class 3 R Laser product

 Class 3 B- Hazardous if the eye is exposed directly , but
diffuse reflections are not hazardous. Protective
eyewear required when direct viewing. Must be
equipped with key switch and safety interlock
 Class 4- Includes all lasers with beam power greater
than 3 B. It can burn skin and cause permanent eye
damage. Can ignite combustible material so fire risk.
Must be equipped with key switch and safety interlock.
Laser radiation
Avoid exposure to beam
Class 3 B Laser product
Laser radiation
Avoid eye or skin exposure to direct or scattered radiation
Class 4 Laser Product

LASER SAFETY
The most prominent safety concern with lasers is the possibility
of damage from exposure to the laser beam. The nature of the
damage and the threshold level at which each type of injury can
occur depend on the beam parameters:
 Wave length
 Beam divergence
 Exposure duration
For pulsed lasers parameters include
 Pulse length
 Pulse repetition frequency

BASIC LASER SAFETY- EXPOSURE
 MPE (Maximum Permissible Exposure)
The highest laser energy exposure for eye or skin for a given
laser that will not cause injury
 NHZ (Nominal Hazard Zone)
Area within which the MPE can be met or exceeded

BEAM HAZARDS
Primary sites of damage
 Eyes
 Skin
Laser beam damage can be
 Thermal (Heat)
 Acoustic
 Photochemical

Many people think that looking into a laser beam can
make them blind. Is that correct?
This fibroma was removed with a 15 watt
surgical CO2 laser, 50 mm focal length.
Can that laser make you blind? NO
It might burn the cornea in or near the focal
area, but not make someone blind!

An Alexandrite
laser for hair removal.
Can this laser make you blind?
NO
A Q-switched Nd:YAG-laser – can it make you
blind if someone shoots right into your eyes?
NO

Lasers are of extremely low risk compared to:
Dart arrows.
Air guns.
Knives.
Stones thrown.
Slingshots.
Practically all weapons.
Broken branches on trees in the forest.
Let us forbid all these things before putting strong
restrictions on therapeutic (and surgical) lasers

 Lasers are used for eye treatments

 It is not "laser" light that may be dangerous.
 It is any light of certain power, and exposure time, in
certain wavelength interval, with certain pulse energy
(if pulsed) with certain geometric configuration
(divergence, solid angle) etc that may cause such
irradiation in the retina that the MPE (maximum
permissible exposure) is exceeded enough.

What is the best protection?
Knowledge.
Safety glasses can be hazardous:
If you use the wrong type, you may think that you are protected,
but instead ...

LASER SAFETY- CHOOSING THE
CORRECT GLASSES
 The safety glasses you wear depend on the type of laser you work
with and your processes.
 Your glasses need to block all the wavelengths in use.
 The optical density of your glasses should block the maximum
power in use especially for invisible wavelengths.
 The optical density and the wavelength must be printed on the
glasses .
 Just because it is the right color does not mean it will stop the laser.

FACTORS TO CONSIDER WHEN CHOOSING
LASER EYEWEAR
 Rx – availability
 Peripheral vision
 Anti-fog capabilities esp. goggles
 Multi wavelength operations , flip options
 Laser inscribed markings
 UV inhibitors to prevent darkening
 Cost ( What’s the cost of an eye)
 Inspect eyewear for pitting, cracking, scratches and discoloration including light
leaks and coating damage prior to EVERY use

POLYMER LASER EYEWEAR
 Translucent laser resistant goggles
 Passed UV and environmental stabilization tests.
 Lenses will not darken over time
 Special caution- UV and CO2 – street wear lenses don’t
absorb these wavelengths

GLASS LASER EYEWEAR
 Not as impact resistant as polymer, but do not scratch
easily.
 Heavier weight , limited frames.
 Glass prescriptions available.
 Made of mineral glass, dielectrically coated mineral
glass, layered laminates of mineral glass, rare earth
minerals.
 Flips in glass base, plastic flip down or plastic combo.

PATIENT EYE CARE OPTIONS
 Gauze, cotton ball, tapes and quarters- looks cheap to patient
and doctors.
 Metal eye shields, extra ocular and intraocular corneal shields.
 Disposable patient shields.
 Laser glasses

EYE SAFETY
 Avoid “eye level” beams
 Avoid situations where the beam is, or might be deflected upward i.e. beam
steering, “flippers,” periscopes.
 Use beam blocks .
 Keep the room lights bright if possible
 Remove or cover all jewellery
 Exercise caution when leaning down to beam-level
 Always look away from table area when bending-down
 Think twice before leaning to table level to get a better look at your
experiment
 Be VERY CAUTIOUS using “IR cards” and Ultraviolet (UV) Sensor
Cards

SKIN AND PHOTOCHEMICAL
THERMAL BURNS
 Ultraviolet (UV)- –UV can cause skin injuries
comparable to a sun burn
 As with damage from the sun, there is an increased risk
for developing skin cancer from UV laser exposure.
 Thermal Injuries
 High powered (Class 4) lasers, can burn the skin and
even infrared (IR) and visible range cause first, second,
and third degree of sun burns and can set clothes on fire.

PHOTOCHEMICAL AND THERMAL
BURNS
 Thermal Skin Burns-Rare; normally requires high exposure
dose of at least several J/cm2; most common from CO2,10.6
μm exposure.
 First degree (erythema), second degree (blistering), and
third degree (charring) burns are possible-dependent upon
exposure dose.
 Delayed effects include skin cancer and accelerated skin
aging
The hazards associated with skin exposure are of less
importance than eye hazards. However, with the expanding
use of higher power laser systems, particularly ultraviolet
lasers, the unprotected skin of personnel may be exposed to
extremely hazardous levels of the beam power if used in an
unenclosed system design.

INTRAOPERATIVE PRECAUTIONS
 Dry combustible items as sponge, towel should not be placed
in sterile field
 Sponges should be moistened and its moisture level should be
monitored
 Cloth and paper drapes not used because flammable,
polypropylene drapes least inflammable.
 Inflammable solutions not used for preparation
 If laser surgery near patient’s teeth such as MLS, teeth
protector which is non inflammable and can withstand laser
impact used.

INTRAOPERATIVE PRECAUTIONS
 Patient should receive preoperative instructions not to use hair
spray, gel or mousse.
 If patients hair near laser impact site, covered with wet sponge.
 Coat any exposed facial hair with water soluble jelly.
 Laser personnel should wear scrub suits, gloves and surgical
gowns to protect the skin.

COMMONLY OCCURING CAUSES OF
LASER RELATED INCIDENTS
 Unanticipated eye exposure during alignments.
 Available laser eye protection not used.
 Intentional exposure occurred to protected persons.
 Incorrect eyewear selection and/or eyewear failure.
 Accidental eye/skin exposure during use.
 Eye /skin hazards were produced of a photochemical origin.

BASIC LASER SAFETY CONTROLS
Administrative Controls
 Warning Signs
 Labels
 SOPs- Class 3B and 4
laser systems
 Training
 Security
Engineering Controls
 Beam Housings
 Shutters
 Attenuators
 Remote viewing devices
 Interlocks/switch lock
receptacles
 Emergency Disconnects

OUT DOOR WARNING SYSTEMS
 Warning sign which states type and wattage of laser
 Appropriate goggles for the specific wavelength of laser in use
to be located outside the door
Door knob warning
signs ( “ Do not
enter”, “ Alignment
in progress”, “ Laser
operating inside”)
should be
temporarily posted
to alert the persons
during beam
alignment

TEMPORARY LASER CONTROLLED
AREA ( e.g. Servicing Laser)
If a temporary laser
controlled area is
established, as in the case
of servicing a laser a notice
sign for temporary laser
controlled area must be
posted.
28

WINDOW COVERING
 No additional covering required for CO2 laser – absorbed
by glass
 For argon and Nd YAG laser- windows covered with
window inserts

ELECTRICAL CONNECTIONS
DO NOT USE
 Frayed electrical cords .
 If significant leak in water hoses.
 Water leakage from laser console.
 Isolated transformer alarms.
 Excessive cords or wires on floor ( trip hazard)

ESSENTIAL REQUIREMENTS
POWER OUTLET REQUIREMENTS
 Nd YAG- 208 volts , 3 phase
 Argon -208 volts, single phase
 CO2 110 volts grounded
WATER SAFETY
 If water leakage- disconnect
 Person should stand on dry floor when plugging the laser
 Laser foot pedal on dry floor. Only one foot pedal is to be used.
 Instruments to be used in laser proximity have dull rough surface to
diffuse any stray energy or constructed of material that will absorb
energy

SMOKE EVACUATION
 Some procedures generate smoke so smoke evacuation required
 High filtration surgical masks must be worn during procedures that
produce plumes.
 Fire extinguisher must be always available
 Container of sterile water always available
 Do not use flammable tapes, skin degreasers, prep solution,
lubricants and drying agents during surgery
 PVC endotracheal tubes not suitable
 Cover rectal area with moist sponges as methane gas is inflammable
 Use non-explosive anaesthetics and localized ventilation in laser
surgery of digestive tracts
 Avoid flammable gases near laser

DEFECTIVE
DO NOT USE
Date ___________
By ___________
Do not Remove
This Label
LOCK OUT/ TAG OUT PROCEDURES
Laser systems have
safety concerns.
Ensures that the equipment
being controlled cannot be re-
energized until the locking
device is removed

ENTRY WAY CONTROLS
Of two types
 Doors and barriers that are interlocked to laser power supply
 Doors and barriers that are not interlocked to laser power
supply.
First option best and provision can be made for selective entry of
personnel

BEAM PATH CONTROL
Done to reduce the nominal hazard zone around the laser
 Use of a mechanically stable , optical table.
 Careful placement of optical components to ensure the beam
path is well defined.
 Keeping the beam path above or below the eye level.
 Use of screens , curtains, window cover.

COLLATERAL RADIATION
Includes any radiation produced by the laser or laser system other
than the beam
 X ray radiation- lead shielding is required to keep the exposure
below the maximum permissible exposure level.
 Ultraviolet and visible radiation- Protection afforded by
protective housing over laser

PANIC BUTTON
 Red mushroom shaped button – to facilitate immediate
shutdown of a laser in an event of emergency such as fire or
sudden or unexpected change in beam direction that creates a
hazard to personnel

EMERGENCY PROCEDURES
May be sudden fire, explosion, release of toxic gas or serious
injury to personnel
 Shut the laser off using panic button or remove the interlock
key
 Evacuate the area
 If fire- evacuate and shout FIRE, activate fire alarm

TRAINING
 Laser education program should be designed to meet
individual’s need
 OT personnel should demonstrate appropriate skill levels
before assuming the responsibility for operating laser
equipment.
 Laser safety operator should be responsible for
1. Laser safety protocol
2. Performing laser equipment preoperative check
3. Operating laser control panel
4. Completing laser documents

SPECIFIC PROCEDURES
LASER SURGERY IN HEAD AND NECK AREA
CO2 LASER- For patient- if patient asleep- saline soaked
sponges over patients eyes and if awake protective goggles.
 For OT personnel – clear goggles over prescription glasses ,
clear glasses with side shields, contact lenses not acceptable

Nd YAG OR ARGON LASER
 For treatment outside eye area- eyes covered with oval gauze
and overlying filtering lenses that correspond to the specific
laser wavelength. Both should be taped securely so no exposed
area through which light can radiate. If patient awake –
protective goggles.
 For treatment of periorbital area- eye can be protected by
holding a covered or dull metal spoon over the eye, to expose
more skin surface for treatment.
 For OT personnel- For argon- Special eyewear with OD> 5,
amber filtered goggles with side shields
 For Nd YAG- Special eyewear OD 4.5, green filtered goggles
with side shields.

SURGERY BELOW HEAD AND NECK
 Patients who are awake- Goggles provided so there is no open
area between the goggle and skin surface where laser light may
enter. Or patients may wear a sleep mask with gauze pads
placed between the mask and face.
 Patients who are asleep- gauze pads taped securely over the
eyes.

EYE WEAR FOR OT PERSONNEL
 For diode- Special eyewear with OD 4
 When using laser through endoscope or microscope- all OT
personnel should wear appropriate eye wear and endoscopic
lens covers with appropriate filtering lenses must be used for
protection.

SAFETY CHECK LIST
PREOPERATIVE
1. EYE PROTECTION- Personnel, patient
2. DOORS PROPER WARNING SIGN- Flashing light on
3. SMOKE EVACUATION
4. FIRE EXTINGUISHER- Room free of inflammables, patient free of
inflammables- hairspray, clothing etc
5. WATER- Laser hoses connected to outlets and turned ON. Excessive
water not leaking from hoses.

6. ELECTRICITY- Electric cords are in good condition, cords
plugged into appropriate outlet, circuit breaker switch in
correct position.
7. TRAFFIC- Laser console, water hoses, and electrical cords are
out of traffic mainstream.
8. GASES- coaxial –proper kind and amount for laser. Assist for
CO2 LASER, co2 for CO2 laser enough for procedure.
9. RECIRCULATION SYSTEM- Off and on as needed, High
and low flows regulated, Suction regulated, Endoscope T piece
ready for use,

10. DELIVERY SYSTEM INSPECTION/PLACEMENT- Fibre, Hand piece,
Micromanipulator.
11. MODIFIED INSTUMENTATION- Retractors, suction, special finish on
instruments, modified endotracheal tubes, modified cottonoids.
12. REINTUBATION EQUIPMENT- ready
13. OBATIN KEY TO LASER
14. BASIN OF STERILE WATER AVAILBLE
15. TEST FIRE LASER
16. CHECK LASER FOR PROPER FUNCTIONING- Check standby/ OFF,
check HIGH/LOW laser power, check all mode and malfunction panels

INTRAOPERATIVE
1. When physician requests laser , turn machine to standby and position
foot pedal for physician.
2. Select mode and power as requested by physician
3. Do not leave laser while in use.
4. Place laser on standby when not in use
5. Turn off the laser before changing gas tanks.
6. Maintain communication with surgeon while operating the laser.

POSTOPERATIVE
1. Turn of laser and remove the key.
2. Return laser key to proper storage.

CONCLUSION
 Safety is everyone’s responsibility !
 Knowledge of Laser science= Ability to perform risk
assessment=development of appropriate safety
policies=safer staff=safer patient care !!!

Laser and operating room safety

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Laser and operating room safety

Similar to Laser and operating room safety (20)

Recently uploaded

Recently uploaded (20)

Laser and operating room safety