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Guidelines for Prevention of TB. Centers for Disease Control & Prevention. Administrative Controls. Infection Control Policies and Procedures Risk Assessment/HCW Screening Investigation of HCW TST Conversions. TB Infection Control Policies & Procedures 1. High index of suspicion for TB
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Guidelines for Prevention of TB Centers for Disease Control & Prevention
Administrative Controls • Infection Control Policies and Procedures • Risk Assessment/HCW Screening • Investigation of HCW TST Conversions
TB Infection Control Policies & Procedures 1 • High index of suspicion for TB • Prompt triage • Prompt initiation of respiratory isolation • AII room under negative pressure (monitored) • UVGI and HEPA filtration as necessary • Limit movement of patient outside AII room • Prompt initiation of appropriate treatment
TB Infection Control Policies & Procedures 2 • Personal respiratory protection during exposure (N-95 respirators)**fit testing req. • Limit employee and visitor exposure • Monitor clinical status by symptoms, laboratory and CXR to ensure appropriate duration of airborne precautions • Appropriate discharge to the community
Respiratory Protection • The ability to filter 1um in size with a filter efficiency of >95% • Fit test to insure face seal leakage of <10% • Making respirators available in at least three sizes • Reuse of Respirators
Why do we place patients in isolation? • Patients who are immunocompromised are placed in a “protective environment” • Patients who have communicable diseases are placed in “airborne infection isolation”(AII) • Patients who have both problems are put in a room with a combination of controls but always protect the staff, visitors and other patients
Protective Environment • Install central or point-of-use HEPA filters for incoming air • Maintain > 12 air changes per hour (ACH) • Maintain positive pressure (> 2.5 Pa) in relation to corridor • Ensure that rooms are well sealed • Properly constructed windows, doors and intake and exhaust ports • Maintain ceilings that are smooth and free of fissures, open joints and crevices • Monitor for leakage
Airborne Spread of Smallpox in the Meschede Hospital Fenner. 1988.Fig. 4.9
AII Rooms • Maintain continuous negative pressure (2.5 Pa) in relation to the air pressure in the corridor and ensure monitoring • Ensure that rooms are well sealed • Provide ventilation to ensure > 12 ACH for new and renovated rooms and > 6 ACH for existing rooms • Direct exhaust air to the outside, away from air intake and populated areas. If this is not practical, air from the room can be recirculated after passing through a HEPA filter, ?UVGI
Guidelines • 2001 AIA “Guidelines for Design and Construction of Hospital and Health Care Facilities - ????NEW July 2006 • 2003 CDC “Guidelines for Environmental Infection Control in Health-Care Facilities” • 2004 JCAHO “Environment of Care – Essentials for Health Care” Fourth Edition
What about an anteroom? AIA Guidelines Section: 7.2.C Airborne Infectious Isolation Rooms does not require anterooms. The requirement for an anteroom was dropped in the 1996-97 edition of the Guidelines on the basis of a study. CDC Guideline: Does not require anteroom. For Viral Hemorrhagic Fever and Smallpox, use AII preferably with an anteroom – if not available use industrial-grade HEPA filters to provide additional ACH JCAHO EC Standard: No reference to anterooms
ASHRAE’s Design Manual(American Society of Heating, Refrigeration, and Air-conditioning Engineers)“HVAC Design Manual for Hospitals and Clinics” 2003
Chapter 12: Room Design On negative air pressure, as is required for Airborne Infectious Isolation Rooms: “…Through dilution, a 500 cubic feet anteroom (for example) with an AVM of 50 cubic feet would experience a 90 percent reduction in the transmission of contaminated air to and from the isolation room. An anteroom is recommended as a means of controlling airborne contaminant concentration via containment and dilution of the migrating air.”
Why add an anteroom or airlock? • To provide a barrier against loss of pressurization, and against entry/exit of contaminated air into/out of isolation room when the door to the airlock is opened • To provide a controlled environment in which protective garments can be donned without contamination before entry into and exit out of room • To provide a controlled environment in which equipment and supplies can be transferred fro the isolation room without contaminating the surrounding area
Creating Isolation Rooms • Funding by governmental agencies to increase isolation capacity • Many healthcare facilities have upgraded or retrofitted existing negative pressure isolation rooms • Many healthcare facilities have purchased “quick fixes” to increase isolation capacity
What’s out there? Source Control – Local Exhaust/Ventilation
What’s out there? Source Control – Local Exhaust/Ventilation
Disclaimer • Following are illustrations of actual products available to healthcare facilities. These are being used for educational purposes only and are not meant to endorse or criticize any individual company or product. I have no financial interest in any healthcare products.
Key Points • There needs to be a clear understanding by all of our goals when using isolation rooms – who are we trying to protect and why. • There needs to be a clear understanding of how to appropriately use the equipment/resources available to accomplish our goals. • There needs to be a clear understanding of how to minimize risks and maximize benefits to patients and health care workers by using the equipment/resources.
Key Points • A portable HEPA device will not create a negative pressure room unless exhaust can be discharged directly to the outside. • Trying to connect a HEPA unit into a return duct to create negative pressure would pressurize the return duct and result in blowback into adjacent rooms. • If the unit is vented directly to the outside, return air grilles must be sealed off – remember to take into account the direction of flow into the attached bathroom.
Key Points • All personnel must understand the use of these devices – housekeeping, nursing. • The portable air filtration device should not be plugged into a power strip or extension cord. Consider using an emergency power outlet. • The HEPA unit must not create an obstruction that would interfere with the proper delivery of health care. • The placement of the device needs to be pre-determined to maximize air mixing for better air scrubbing.
Key Points • The intake of the device should be placed as close to the suspected source of contamination. • The device should be placed so that it does not draw contaminated air past the breathing zone of the caregiver. • The air flowing out of the device must not be directed in a way that would cause discomfort to patients, visitors and staff.
Key Points • The air flow needs to be appropriate for the size of the room to give the desired air exchanges per hour. Consider a locked panel to prevent a change in the air flow controls. • Rooms in which the devices may be utilized should be chosen beforehand ensuring that the noise created is not disruptive to others. • If the unit is ducted to the outside or into the existing ventilation system, ensure that an appropriately fitting interface is available.
Key Points • Place HEPA filters over exhaust grilles that cannot be blocked. • The use of the portable filtration devices should be guided by a written policy that is facility-specific with appropriate reviews and approvals from infection control, administration, clinical and facility engineering and the departments in which the units will be used. • Healthcare facilities should have a checklist establishing the proper room use.
Key Points • Based on manufacturer’s recommendation and any additional suggested protocol from facility maintenance, a standard routine maintenance procedure should be developed for the unit. This should include: • Changing of pre-filters. Be sure to include details of PPE and proper disposal of filters. • Operational check for proper operation. • Interior cleaning of the unit • Changing of UV lamp • General electrical and mechanical safety check
Key Points • Clinical and/or facility engineering should check the machine on a daily basis while in use and measure the degree of negative pressure between the room in which it is situated and adjacent/affected areas.
Key Points • The HEPA device must be leak tested and certified. This should be done initially when the equipment is received, at least annually thereafter, and every time the HEPA filter is changed. The frequency of changing the HEPA filter should be based upon manufacturer’s recommendation.
Key Points • Policies and procedures should specify recommended PPE when performing maintenance of the unit. • Maintenance should be performed in an area away from patient care.
Pressure-measuring devices Measure pressure at the bottom of the door Audible warning with a time delay Check continuous monitoring devices at least monthly using smoke tubes Monitoring Negative Air Pressure
Smoke Test • Checked daily • Hold 2 inches from bottom of door • If room air cleaners are used they should be running • Door must be closed
UV Radiation • Used to supplement other engineering controls • Duct Irradiation • To recirculate air from an isolation room back into the room. • Used in general use areas where air is recirculated back into general ventilation • Upper Room Air Irradiation • Mounted on ceiling or wall
Effectiveness of UV Systems • Intensity of UVGI • Duration of contact • Relative humidity
UV Safety Issues • Short Term Exposure • Education • Labeling • Maintenance • Monitoring
Operating Room • Place bacterial filter on • patient endotracheal tube • Expiratory side of breathing circuit of a • Ventilator • Anesthesia equipment • No anterooms • Keep doors closed • Control traffic • If possible schedule case at end of day
Postoperative recovery • Private room • Negative air pressure
Autopsy rooms • Negative air Pressure • 12 ACH • Increase ventilation if possible using HEPA –filtered air or UVGI recirculation systems • Exhausted directly to outside • Respiratory protection