TSE: Instrument Management in Surgery and Dentistry Current CDC Recommendations

1
TSE Instrument Management in Surgery and
DentistryCurrent CDC Recommendations

• Lynne Sehulster, PhD, M(ASCP)
• Division of Healthcare Quality Promotion
• Centers for Disease Control and Prevention
• Atlanta, GA 30333

2
Information Resources

• WHO Infection Control Guidelines for TSEs - 1999
• www.who.int/emc-documents/tse/whocdscsraph2003c.h
  tml
• CDC Infection control Q A
• www.cdc.gov/ncidod/diseases/cjd/cjd_inf_ctrl_qa.h
  tm
• CDC Guidelines for Infection Control in Dental
  Health-Care Settings - 2003 www.cdc.gov/mmwr/PDF/
  RR/RR5217.pdf

3
Instrument Management Strategy Elements

• Patient Status
• Confirmed or suspected CJD case
• Low or no risk patient
• Tissue infectivity level
• High-, Low-, or no infectivity
• Instruments and surgical procedures
• Tissue contact

4
Tissues and InfectivityPatients with Confirmed
or Suspected CJD

• High infectivity tissues
• Brain, spinal cord, eyes
• Low infectivity tissues
• Cerebrospinal fluid, kidneys, liver, lungs,
  lymph nodes, spleen, placenta
• Based on Table 2, WHO Infection Control
  Guidelines for TSEs 1999

5
Neurosurgery Strategies for Infection Control

• Prion-specific reprocessing should be employed
  for
• Any neurosurgical procedure performed on a
  confirmed or suspected TSE patient
• Neurosurgery performed for diagnosis
• Neurosurgery to obtain non-lesionous biopsy
  material
• Consider demographics of TSE patients

6
Decontamination Levels for Risk Categories
Patient Category Tissue Category Decon Options
Confirmed or suspected TSE case High infectivity Low infectivity Annex III Annex III
Relative of patient with familial TSE High infectivity Low infectivity Annex III (Annex III)
All of the above categories No detectable infectivity Routine procedures
Confirmed or suspected vCJD case All tissue categories Annex III
WHO Infection Control Guidelines for TSEs
Annex III 1999 WHO guidance is controversial
on this topic.
7
Reprocessing Parameters TSEHeat-Resistant
Instruments

• Immerse in 1N sodium hydroxide (NaOH) and heat in
  a gravity displacement autoclave at 121C for 30
  min, cool, clean, rinse, and follow with
  conventional autoclaving
• WHO Infection Control Guidelines for TSEs Annex
  III 1999
• Measures to prevent sodium hydroxide spills in
  autoclaves include use of a container with rim
  and lid designed to collect condensation. Use
  caution. Let cool to minimize exposure to
  hydroxide vapor.
• Brown and Merritt. Am J Infect Control 2003 31
  257-60

8
Reprocessing Parameters TSEHeat-Resistant
Instruments

• Immerse in 1N sodium hydroxide (NaOH) or 20,000
  ppm sodium hypchlorite for 1 hr, transfer to
  water, heat in a gravity displacement autoclave
  at 121C for 1 hr, cool, clean, rinse, and follow
  with conventional autoclaving OR
• Immerse in 1N sodium hydroxide (NaOH) or 20,000
  ppm sodium hypochlorite for 1 hr, rinse, heat in
  gravity displacement autoclave (121C) or porous
  load autoclave (134C) for 1 hr, cool, clean,
  rinse, and follow with conventional autoclaving.
• WHO Infection Control Guidelines for TSEs Annex
  III 1999

9
Reprocessing Parameters TSEHeat-Sensitive
Instruments

• Instruments having contact with high- and
  low-infectivity tissues
• High brain, spinal cord, eyes
• Low cerebrospinal fluid, kidneys, lungs, liver,
  lymph nodes, spleen, placenta
• Disposable instruments discard
• Reusable instruments soak in 2N NaOH or
  undiluted sodium hypochlorite for 1 hr, rinse,
  clean, reprocess with low-temperature process

10
Chemicals / Autoclaving Effects on Instruments

• Inexpensive carbon-steel instruments are easily
  damaged
• Gold plating damaged by sodium hypochlorite
• Soldered and welded joints damaged by sodium
  hypochlorite
• Autoclaving in NaOH discolored instruments
• NaOH did not affect instrument function

Brown, Merritt, Woods, Busick J Biomed Mater Res
Part B, 2005 72 186-90
11
JCAHO Sentinel Alert No. 20 June 2001

• Major points emphasized
• Atypical clinical presentations possible
• Time interval between biopsy and pathology report
  should be as short as possible
• Neurosurgical instruments should not be reused
  while diagnosis is pending
• JCAHO recommends
• Policies and procedures for appropriate
  reprocessing
• Quarantine instruments until diagnosis is
  confirmed

12
Practical Advice

• Quarantine the instruments
• Suitable if the time interval between surgery and
  confirmation of the diagnosis is short
• Have sufficient instrument inventory to
  accommodate this practice
• Keep instruments moist while awaiting release for
  decontamination and reprocessing

13
Practical Advice II

• To minimize potential exposures to patients in
  the event that instruments are returned to
  central sterile units before the diagnosis is
  confirmed
• Reprocess neurosurgical instruments as
  recommended
• Consider instrument tracking
• Restrict instruments in neurosurgery trays to
  those trays only

14
More Research is Needed

• Evaluate decontamination, cleaning, and
  reprocessing processes as are currently available
  in health care
• Cleaners enzymatic, alkaline
• Terminal reprocessing peracetic acid, hydrogen
  peroxide gas plasma
• Effects of repeated cycles of cleaning and
  conventional autoclaving
• Potential for prion contamination of other
  surfaces in reprocessing areas

15
CDC- Infection Control for Known CJD or vCJD
Dental Patients

• Use single-use disposable items and equipment
• Consider items difficult to clean (e.g.,
  endodontic files, broaches, carbide and diamond
  burs) as single-use disposable and discard after
  one use

16
CDC- Infection Control for Known CJD or vCJD
Dental Patients

• Keep instruments moist until cleaned and
  decontaminated
• Clean thoroughly and steam autoclave at 134C for
  18 minutes. This is the least stringent of a list
  of sterilization methods offered by WHO
• Do not use flash sterilization for reprocessing
  instruments or devices

17
Summary Dentistry

• Risk of transmission of CJD during dental
  treatment is low
• No documentation of prions in human oral tissues
  
• No published reports of an association of CJD
  infection with dental treatment
• Additional precautions beyond Standard
  Precautions might be warranted for known CJD or
  vCJD patients

18
CDC PerspectiveAt-Risk Patients in the U.S.

• Blood relative of patient with inheritable forms
  of TSEs
• Are asymptomatic individuals truly at risk?
• WHO no consensus - relatives of familial cases

19
Thank You!

• Centers for Disease Control and Prevention
• National Center for Infectious Diseases
• Division of Viral and Rickettsial Diseases
• Division of Healthcare Quality Promotion