TSE: Instrument Management in Surgery and Dentistry

Current CDC Recommendations

Lynne Sehulster, PhD, M(ASCP)

Division of Healthcare Quality Promotion

Centers for Disease Control and Prevention

Atlanta, GA 30333

Information Resources

WHO Infection Control Guidelines for TSEs - 1999:

www.who.int/emc-documents/tse/whocdscsraph2003c.html

CDC Infection control Q & A:

www.cdc.gov/ncidod/diseases/cjd/cjd_inf_ctrl_qa.htm

CDC Guidelines for Infection Control in Dental Health-Care Settings - 2003 www.cdc.gov/mmwr/PDF/RR/RR5217.pdf

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

Tissues and Infectivity:Patients 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

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

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.

Reprocessing Parameters: TSEHeat-Resistant Instruments

Immerse in 1N sodium hydroxide (NaOH) and heat in a gravity displacement autoclave at 121°C 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

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 121°C 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 (121°C) or porous load autoclave (134°C) for 1 hr, cool, clean, rinse, and follow with conventional autoclaving.

WHO Infection Control Guidelines for TSEs: Annex III 1999

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

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

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

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

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

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

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

CDC- Infection Control for Known CJD or vCJD Dental Patients

Keep instruments moist until cleaned and decontaminated

Clean thoroughly and steam autoclave at 134°C 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

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

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

Summary: DentistrySummary: Dentistry

CDC Perspective:At-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

Thank You!

Centers for Disease Control and Prevention

National Center for Infectious Diseases

Division of Viral and Rickettsial Diseases

Division of Healthcare Quality Promotion