Occupational eye injuries and management

1. Occupational eye health in
health care workers
Department of Ophthalmology
Christian Medical College
Vellore

2. Objectives
• Potential occupational
eye injuries
• Potentially hazardous
areas
• Hazard identification
• Surveillance system
• Personal protective
equipment for eye
• Engineering checks
• Awareness capsules
• Eye safety policy

3. Why look at eye hazards
• Absenteeism
• Cataract
• Potentially blinding:
– Retinal burns
– Perforating eye injuries
– Severe chemical injuries
• ? Life threatening:
– Blood borne viral
transmission through
splashes

4. Questionnaire
• Work related eye injuries in your department
• What eye hazards
• How can it be reduced
• Do health care workers wear PPE for the eye
at your place
• Do you have an eye safety policy

5. Epidemiology
• Eye injuries: 3- 4% of all
occupational injuries*
*Xiang H, Stallones L, Chen G, Smith GA. Work-related eye
injuries treated in hospital emergency departments in the
US. Am J Ind Med. 2005 Jul; 48(1):57-62

6. Potential Hazards
• Physical Hazards
– Foreign Bodies /
Missiles
– Radiation hazard
– Laser Induced damage
– Thermal
• Chemical hazards
• Biological hazard
– Infections
– Body fluid splashes
• Eye strain

7. PHYSICAL HAZARDS

8. DENTAL
PROCEDURES
• Hazards: Aerosol splash (saliva
and blood), flying debris
• Eye injuries: Ten % of
occupational injuries to dental
personnel 9 year period in a
dental hospital.
• Eye protection compliance
57% when using laboratory
cutting equipment.
British Dental Journal 2007; 203: E7; 1- 5

9. Optical shop : Spectacles lens
CUTTING GRINDING

10. Engineering / Maintenance/ Non
clinical support services
• Engineering controls
– E.g. machine guards
– Welding curtains for arc
flash protection
• Administrative controls
– E.g. areas “off limits” for
those uninvolved
• Proper protective eyewear
– Painting, breaking down

11. ELECTROMAGNETIC SPECTRUM
10-14
10-12
10-10
10-8
10-6
10-4
10-2
1 102
104
106
108
Wavelength in Meters
1010
108
106
104
102
1 10-2
10-4
10-6
10-8
10-10
10-12
10-14
Broadcast
Short wave
TV
FM
Radar
Infrared
Near Far
Visible
Ultraviolet
X Rays
Gamma Rays
Cosmic Rays Power
Transmission
Ionizing Radiation Nonionizing Radiation
Energy - Electron VoltsHigh Low
LASER
RADIATION

12. Departments: Radiation Exposure
Department
Radio diagnosis
Radiotherapy
Nuclear Medicine
Cardiology
Operating Theaters
Gastroenterology
Orthopaedics
Haematology ((BMT)
Dental
Stem Cell
Transfusion Medicine

13. Dose Response Tissue
Examples of tissue Sensitivity
Very High White blood cells (bone marrow)
Intestinal epithelium
Reproductive cells
High Optic lens epithelium
Esophageal epithelium
Mucous membranes
Medium Brain – Glial cells
Lung, kidney, liver, thyroid,
pancreatic epithelium
Low Mature red blood cells
Muscle cells
Mature bone and cartilage

14. Radiation induced
cataract
• Cataract – deterministic effect
with threshold; may be even
linear – no threshold
• An annual limit of 15 rem
(0.15 Sv) to the lens of the
eye
• Latency α 1 / Dose

15. Catheterization and Cardiovascular Interventions
76:826–834 (2010)

16. Protection
• Monitoring dose
received
• Personal protective
equipment

17. Management
Cataract Surgery Intraocular Lens Implantation

18. Light Amplification by Stimulated
Emission of Radiation (LASER)
• Non Beam Hazards
– Electrical
– Explosion
– Compressed Gases
– Dyes and Solvents
– Fire
• Beam Hazards

19. American National Standards Institute
(ANSI)
• Maximal Permissible Exposure
– The maximum permissible exposure (MPE) is the
highest power or energy density (in W/cm2 or J/cm2)
of a light source that is considered safe
• Nominal Ocular Hazard distance
– distance from the source at which the intensity or the
energy per surface unit becomes lower than the MPE
• Nominal hazard Zone
– space within which the level of direct, scattered or
reflected laser light emitted during laser operation
exceeds the MPE
https://www.lia.org/PDF/Z136_1_s.pdf

20. Commonly used lasers
TYPE Radiation type /
wavelength in nm
Examples of application
Carbon dioxide (gas) Infra red (10600) Surgery
Argon (gas) Visible, blue (488),
green (514)
Ophthalmology, Plastic Surgery
Krypton 532 (gas) Visible green (532) Surgery
Nd YAG (continuous wave, solid
state)
Infrared (1064) General Surgery
Nd YAG (Q switched, solid state) Visible (632) Ophthalmology
Helium Neon (gas) Visible red (632) Alignment for aiming invisible
beams
Ruby (solid) Visible red (694) Plastic Surgery, Dermatology
Rhodamine (dye) Visible red (630) Treatment of Malignancies
hwww.ccohs.ca/oshanswers/phys_agents/lasers.html

21. Laser - Biological effects in the eye
Spectral domain Wave length Eye (biological effects)
Ultraviolet B & C 200 – 315 nm Photokeratitis
Ultraviolet A 315 – 400 nm Photochemical cataract
Visible 400 -780 nm Photochemical and
thermal retinal injury
Infrared A 780 – 1400 nm Cataract and retinal burn
Infrared B 1.4 to 3.0 microns Corneal burn, aqueous
flare, cataract
Infrared C 3 to 1000 microns Corneal burn only

22. Clinical manifestations
Photokeratitis Foveal burn
Tear substitutes / rest Systemic / topical steroids

23. Factors
• Types of beam:
– Direct :NEVER UNDER ANY
CIRCUMSTANCES LOOK INTO
ANY LASER BEAM
– Specular reflection
– Diffuse
• Class IV can initiate fire!
• Duration
– Less than 0.25 s safe BLINK
• Class 1, 2 A and 2 (direct)
• intrabeam or specular
reflection viewing of Class
3a, 3b, or 4 or diffuse
Class 4 happens before
• Class
– 1 : No danger
• E.g CD ROM players
– 2 : Direct viewing
dangerous
• E.g Scanner at sales
points
– 3: Direct and Specular
• E.g Medical
– 4. Serious hazard
• Research

25. Laser pointers
• Visible light
• Output power:
– 1 to 5 mW directly at eye,
– retinal irradiance similar
to that caused by staring directly at the sun
• blink reflex and aversion response.
• near 550 nm with less than 1 mW : safe

26. Laser retinal injury
PROTECTION
• Engineering controls :
– Filters in machine
– Goggles
– Shutters /Key Switch /
• Avoid direct viewing
• Warning signs
MANAGEMENT
• Corticosteroids
• Rarely surgery

27. Thermal Hazards
• Central Sterilization
Supplies department
• Injury
– Cell death - limited to
the superficial
epithelium;
– thermal necrosis and
penetration can
occur.

28. CHEMICAL HAZARDS

29. Chemical Hazards
• Vulnerable
– House keeping Staff
– Laboratory Personnel
– Preclinical teaching
departments
– Service laboratories
– Personnel in the
Operating room
• Responsible for 7% of
work-related eye
injuries treated at US
hospital emergency
departments.
• 60% of chemical injuries
occur in workplace
accidents

30. Chemical Injuries
• Potentially blinding in 1
in five
• Approx 15 % of severe
injuries get functional
vision
• Acids / alkalis, latter
being worse

31. Anatomy

32. Transferring formalin from
40% container to another
container
Diluting the 40% formalin to
make a solution of 10%
concentration

33. Lifting body out of formalin tank and
transferring to a trolley and back

34. Management
• First Aid : Irrigate eye with sterile
Balanced salt solution, ringer
lactate or even tap water for 15 -
20 min ASAP
• Consult Ophthalmologist
– Agent / pH
– Slit lamp examination
– Medical : Steroid / cycloplegic /
anitbiotic / Vitamin C
– Surgical if extensive limbal stem cell
loss

35. BIOLOGICAL HAZARDS

36. Infection
• Microbes :
– Conjunctivitis (e.g.,
adenovirus, herpes
simplex, Staphylococcus
aureus)
– Systemic infections,
including bloodborne
viruses (e.g. hepatitis B
and C viruses, human
immunodeficiency
virus), herpes viruses,
and rhinoviruses.
• Mode of introduction
to eye
– Fomites
– directly (e.g., blood
splashes, respiratory
droplets generated
during coughing or
suctioning)
– touching the eyes with
contaminated fingers or
other objects : E.g
microbiology labs)

37. Conjunctivitis
• Adenovirus (3, 7, 8, 19 serotypes) -
nosocomial epidemic outbreaks
• Spread:
– Fomites / ophthalmic instruments
– Contaminated hand to surfaces
• Areas high risk
– Eye / staff clinics
– Neonatal ICU
– Long term facilities

38. SIGNS

39. Hemorrhagic: Enterovirus
MembranesVisual blur : corneal involvement

40. PREVENTION

41. Preventive aspects-
Conjunctivitis
• Epidemic potential,
absenteeism, economic loss
• Delayed treatment in
ophthalmology for primary
disorders, secondary
infections
• Infective as long as
symptomatic (with
discharge) up to two weeks
Identify
Educate
Treat
Isolate
Dispose
Reassure
CONTROL
EPIDEMIC

42. Body Fluid splashes - EYE
• Low risk of transmission
• Prophylaxis
recommended
AREAS LIKELY
• Blood collection Areas
• Dialysis suites
• Operating room
personnel

43. Body Fluid splashes

44. ‘Eye Strain’: Computer vision syndrome
PREVENTION
• Ergonomics
• Breaks 20 min, 20 secs
• Tear Substitutes
HIGH RISK
• Radiology
• CHIPS
AWARENESS

45. Eye protection devices
• Goggles
• Face protection Shields
• Safety glasses
(polycarbonate)
• Full face respirators
• Prescription users :
additional eyewear
• Z87 DEVICES

46. DO NOT
• rub when you suspect debris
• irrigate when suspecting perforation or
foreign body
• use ordinary prescription glasses, reading
glasses, sunglasses, and contact lenses
instead of protective eyewear.
• work without appropriate spectacle
correction: leads to injuries at workplace

47. Eye safety policy
• When must you wear PPE for eye
• What enforcement processes are in place
• How do you get help when there has been
health care related eye injury
• How do you report
• How do you rectify lapse if any

48. Occupational Eye Injury
Sustained
eye injury
First Aid
Inform OSH
team / SSHS
Eye consult
Manage
Preventive
measure assess
/ set up
Awareness
Compliance

49. Monitoring
• Reporting system for eye
– Acute eg : splashes / missiles report to emergency
– Chronic eg radiation induced damage will need
systems to be placed
• Preferably all acute eye injuries on the same
line as needle stick
• Customize staff health checks on the basis of
hazard risk in addition to general check up

50. Future plans
• Detailed eye hazard assessment
• Awareness capsules eg before the
conjunctivitis season
• Mandatory staff training modules / CME
• Surveillance systems
• Baseline evaluation of departments with
radiation for cataract

51. Eye safety checklist for health care
• Create a safe work environment
– Indications
– Safety features of instruments in place and
functional
– Workers educated on safe use
– Bystanders kept out e.g Laser sessions
• Identify
– Primary Hazards
– Hazards posed by work happening on premises !!!

52. Eye safety checklist for health care
• Prevent injury/ Good work practices
– If PPE, Ensure good condition / fit / and availablility
– If procedure ensure availability of preventive
preparation eg Sterilium
• Prepare for eye injuries esp chemical splashes
– Have sterile /appropriate solution for irrigation and
equipment ready if necessary

53. Acknowledgements
• Patients / Departments of Ophthalmology,
Anatomy, Dental and Orthopedics for the pictures