chapter 10 pt2 darby
Engineering Controls
Engineering controls are the most effective way to reduce workplace injuries, according to OSHA.
They involve devices or equipment that eliminate or reduce hazards.
Examples in oral healthcare:
Devices that contain or remove sharp items.
Anesthetic syringes with retractable needles or shielding.
Anesthetic needles with shielding mechanisms (Fig. 10.2).
Disposable scalpels that don't require blade removal.
Scalpel handles with retractable blades or guards.
Safety IV needles and needle-free ports for IV lines.
Use engineering controls when they can reduce exposure to blood or body fluids.
OSHA mandates using sharps with engineered injury protection if they offer superior protection and don't interfere with patient care.
These devices reduce the risk of percutaneous injuries.
Core Infection Prevention Practices
In 2014, HICPAC (an advisory group to the CDC) adopted the Core Infection Prevention and Control Practices for Safe Healthcare Delivery in All Settings.
These practices are widely agreed upon and unlikely to change with further research due to strong evidence or ethical concerns.
Core Practice Categories (Table 10.3)
Leadership support: Visible support from all levels of the healthcare facility is crucial.
Education and training: Healthcare personnel should be trained on infection prevention, adapted to their roles and the facility.
Patient, family, and caregiver education: Provide information on infection spread, prevention, and when to seek re-evaluation. Materials should accommodate diverse education levels and languages.
Performance monitoring and feedback: Measures should be tailored to care activities and the population served.
Standard precautions: Basic practices applicable to all patient care, regardless of infection status, in all settings.
Hand hygiene: Alcohol-based hand rubs are preferred over soap and water when hands aren't visibly soiled, due to better compliance and less irritation.
Environmental cleaning and disinfection: Facility policies should be guided by the best available evidence, considering risks and benefits.
Infection and medication safety: Refer to the "Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings, 2007" for details.
Risk assessment and PPE use: PPE (gloves, gowns, masks, respirators, goggles, face shields) are secondary to administrative and engineering controls.
Minimizing potential exposures: Refer to the "Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings, 2007" for details.
Reprocessing reusable medical equipment: Follow manufacturer's instructions, provide training, and document competencies.
Transmission-based precautions: Implementation varies based on setting (inpatient, outpatient, long-term care) and facility design.
Temporary invasive medical devices: Remove devices early and promptly, and healthcare personnel should be knowledgeable about device risks and infection prevention interventions.
Occupational health: Healthcare organizations and personnel must adhere to federal, state, and local requirements concerning immunizations, work policies, and reporting of illnesses.
Standard Precautions
Standard precautions involve HCP following the same protocols for all patients, regardless of infectious status or health history.
Consistent use ensures safe oral healthcare delivery.
Health history alone cannot reliably identify all persons with HIV, HBV, or other blood-borne diseases.
Standard precautions do not depend on health, dental, and pharmacologic histories.
These precautions protect both HCP and patients from disease transmission.
Standard precautions are a synthesis of universal precautions and body substance isolation precautions.
Apply to:
Blood
Other bodily fluids, secretions, and excretions (except sweat), regardless of visible blood
Non-intact skin
Mucous membranes
Standard precautions apply to all body fluids, excretions, and secretions, except sweat and tears.
Transmission-Based Precautions
Certain diseases require additional measures beyond standard precautions, based on the transmission route.
These precautions may be necessary for diseases like TB, influenza, varicella, measles, and COVID-19.
Acutely ill persons with these diseases should not be treated in a typical dental outpatient setting while infectious.
Understanding precautions for all transmission routes is critical because:
Some DHCP are based in hospitals or work part-time in hospital settings.
Infected persons may seek urgent treatment at outpatient dental offices.
DHCP may become infected with these diseases.
Necessary precautions may include patient placement (isolation), adequate room ventilation, respiratory protection (N95 masks), or postponing nonemergency dental procedures.
The CDC has identified three categories of transmission-based precautions:
Contact
Droplet
Airborne
These are used when standard precautions alone are insufficient.
For diseases with multiple transmission routes (e.g., measles), multiple categories may be used.
Standard precautions always apply in addition to transmission-based precautions.
In clinically active TB, standard precautions alone aren't enough.
Risk of TB transmission is reduced by administrative, environmental, and personal respiratory protection.
For patients with known or suspected active TB, the CDC recommends:
Evaluating the patient away from others, with the patient wearing a surgical mask or covering their mouth and nose when coughing or sneezing.
Deferring elective dental treatment until the person is noninfectious.
Referring patients needing urgent care to a facility with TB engineering controls and a respiratory protection program.
Health History
The health history is important for:
Understanding the patient's overall health
Assisting in making appropriate care and referral decisions
DHCP should be aware of signs and symptoms of infectious diseases and steps to minimize transmission risk.
This is particularly important for active TB, with symptoms like coughing, chest pain, sweating, weight loss, night sweats, and fever.
Tuberculosis Considerations for Dental Healthcare Personnel (Box 10.4)
Coughing (especially if persistent and with blood) is a key indicator of infection.
Patients with active or suspected active TB should be isolated, asked to wear a face mask, and encouraged to contact their physician.
The tuberculin skin test (TST), previously known as the Mantoux test, is a common screening test.
It involves an intradermal injection of purified protein derivative (PPD) into the forearm.
The area is observed for 48-72 hours for a wheal (raised, red area) of at least 10 mm.
Repeating the test may be recommended if it's been several years since the last test to rule out false-negative results.
For HIV-infected individuals, a 5-mm wheal is an indication of infection.
A positive TST result indicates infection with the bacterium but not necessarily active disease.
Approximately 10% of infected individuals develop active TB in their lifetime; about 5% shortly after exposure and 5% later in life due to a compromised immune system.
A positive TST may also be due to a previous TB vaccine called bacillus Calmette-Guérin (BCG).
BCG is often given to people in countries with a high prevalence of TB to prevent childhood TB meningitis.
A blood test called an interferon-gamma release assay (IGRA) may be used to rule out false-positive tests in those vaccinated with BCG.
Most people with a positive TST result receive preventive chemotherapy for 6 months, typically with isoniazid (INH).
To treat active infection, physicians use INH with other medications like rifampin and pyrazinamide.
Drug-resistant TB cases do not respond to traditional therapy and are more likely to result in death.
Work Practice Controls
Work practice controls reduce the likelihood of exposure to bloodborne pathogens by altering task performance.
Examples:
Using a stabilized sponge or cotton rolls to wipe instruments instead of wrapping gauze around a finger.
Proper patient positioning (14- to 18-inch focal distance) to reduce exposure to contaminated droplets. Magnifying loupes may assist.
Using a high-speed evacuator while spraying air and water.
Using an ultrasonic cleaner, washer, or washer/disinfector to decontaminate instruments before sterilization.
Using a one-handed scoop technique to recap used anesthetic needles.
If a suitable engineering control is available, it should be implemented instead of a work practice control.
Protocols to prevent percutaneous injuries:
Use medical devices with engineered safety features.
Never recap needles by hand.
Never disengage needles from a single-use syringe.
Use a holding device to remove needles from reusable syringes.
Dispose of needles and sharps in appropriate containers.
Avoid hand contact with sharps.
Never wipe instruments on gauze in a hand or wrapped around a finger; use a commercial safe wipe or sponge device.
Announce instrument passes.
Create a neutral zone for sharps.
Use appropriate cleanup procedures to minimize hand contact with sharps.
Work-practice controls have a significant impact on preventing blood-borne disease transmission; over 90% of exposures in dental settings are associated with needles or other sharp devices.
Most transmissions occur outside of the mouth and on the hands and fingers of the DHCP, and are preventable with proper caution and safer devices.
Administrative Controls
Administrative controls reduce or eliminate hazards through actions such as rotating duties and taking breaks.
These are used in combination with engineering and work practice controls.
Personal Protective Equipment (PPE)
PPE includes protective clothing, eye protection, airway protection, and other attire to protect DHCP from blood and body fluid exposure.
Work practice and engineering controls are the preferred methods of protection.
PPE is indicated when those controls will not prevent exposure.
The PPE should protect the skin, clothing, eyes, mouth, and other mucous membranes.
Base the selection of protective attire on the nature of the procedure and anticipated exposure risks.
Do not base the selection of PPE on the infectious disease status of the patient; use the same precautions for each patient.
Eye and Face Protection
Appropriate eye protection includes goggles, glasses with solid side shields, or a face shield.
The CDC recommends and OSHA regulates that protective eyewear meet standards for spatter protection.
HCP who wear prescription eyeglasses should consult an eyecare professional to ensure the eyewear meets standards for protective eyewear or whether they should use goggles or face shields that fit over the prescription eyewear.
Masks
Surgical masks protect the mucous membranes of the nose and mouth from spatter.
Wear masks under the same circumstances as eye protection.
Base the selection of masks on comfort, fit, and filtration level.
Surgical face masks are divided into performance classes based on fluid resistance, bacterial filtration efficiency, submicron particle filtration efficiency, and flame spread potential.
When laser technologies are used, additional eye protection may be required.
Every pair of safety goggles or safety glasses intended for use with laser beams must bear a label with the following information:
Laser wavelengths in use
Optical density of those wavelengths
Visible light transmission
Follow recommended manufacturer instructions for cleaning and disinfecting protective eyewear.
The FDA provides specific guidance to manufacturers for clearing surgical masks for the market.
The American Society for Testing and Materials (ASTM) rating designation recognized by the FDA includes levels 1, 2, and 3, with level 3 providing the highest barrier performance.
Clinicians should consider using a level 2 or level 3 mask for most dental hygiene procedures, as they are likely to produce some level of splatter.
Respirators and Respiratory Protection
During the COVID-19 pandemic, the CDC issued interim IPC guidelines that included the use of respirators in place of face masks for protection against airborne transmission.
Respirators provide greater protection for the respiratory system.
Respiratory protection should be used when performing aerosol-generating procedures, particularly on patients who are suspected or confirmed to have infections that are transmitted through aerosols, including SARS-CoV-2.
DHCP should correctly wear recommended PPE (including NIOSH-approved N95 equivalents or higher-level respirators) and use other mitigation methods designed to minimize droplet spatter and aerosols, including four-handed dentistry, high evacuation suction, and dental dams.
Respirator fit testing, medical evaluation, education, and training are important elements of a comprehensive respiratory protection program.
OSHA's Respiratory Protection Standard (29 CFR1910.134 and 29 CFR 1926.139) defines the specific regulations to develop, implement, and manage a respiratory protection program.
Protective clothing
Protective clothing (e.g., reusable or disposable gown, laboratory coat, uniform) should cover personal clothing and skin (e.g., forearms).
The protective clothing provides a barrier to protect work clothes (i.e., scrubs) or street clothes from exposure to spray or spatter generated during dental procedures.
In most dental settings, a long-sleeved lab coat that falls at or below the knees is adequate.
However, during exposure-prone procedures, such as surgical procedures, the DHCP may need a more fluid-resistant material.
Protective clothing is removed before leaving the work area, including during breaks or going into nonclinical areas of the facility.
Scrubs alone are not protective attire and should be worn in combination with a long-sleeved gown or lab coat; the gown or lab coat is the protective attire.
OSHA regulations require the employer to arrange for laundering reusable protective attire.
Gloves
Gloves used for dental and dental hygiene procedures fall into three categories:
Medical examination gloves: Nonsterile gloves in various sizes and materials.
Sterile surgeon's gloves: Sterile gloves individually packaged in sized pairs, indicated for oral surgical procedures.
Heavy-duty utility gloves: Puncture-resistant gloves used when handling contaminated sharps to reduce risk of accidental puncture injury (Fig. 10.5).
The CDC recommends that DHCP:
Wear medical gloves when a potential exists for contacting blood, saliva, OPIM, or mucous membranes.
Wear sterile surgical gloves in connection with surgical procedures.
Wear a new pair of medical gloves for each patient.
Promptly remove the gloves after use and immediately perform hand hygiene.
Remove gloves that are torn, cut, or punctured, and wash hands before regloving.
Medical gloves and sterile surgeon's gloves are regulated by the FDA.
Dermatitis or allergic reactions may arise from exposure to materials used in the manufacture of gloves.
Many reactions are the result of contact with chemicals, but a small percentage involve a potentially serious allergic reaction to the proteins found in natural rubber latex.
Today, most medical examination gloves are made of nitrile rubber, not latex.
Hand Hygiene
Hand hygiene is the most important behavior in the prevention of disease transmission.
The preferred method for hand hygiene depends on the type of procedure, the degree of contamination, and the desired persistence of antimicrobial action on the skin.
Remove transient microbial flora and disease by cleaning the hands with detergent and water.
The presence of colonized or resident flora on the hands requires the use of antiseptic agents.
For routine dental procedures (e.g., screening, examination, non-surgical procedures), wash hands with either plain or antimicrobial soap and water. If the hands are not visibly soiled, an alcohol-based hand rub is adequate.
Hand hygiene for surgical procedures (e.g., periodontal surgery, surgical extraction of teeth, biopsy) requires surgical hand antisepsis to eliminate transient flora and reduce resident flora.
Rings and hand jewelry should be removed before performing hand hygiene.
The CDC recommends keeping fingernails short, with smooth, filed edges to allow thorough cleaning and prevent glove tears.
The CDC further recommends healthcare personnel not wear artificial fingernails or extenders when having direct contact with patients.
Dermatitis may arise from the effects of frequent use of hand hygiene products and exposure to water.
Strategies to help maintain good skin integrity:
Thoroughly dry hands after washing with soap and water and before donning gloves.
Use powder-free gloves.
Frequently use appropriate lubricating hand lotions throughout the day.
Use cool water when washing hands.
Protect hands from chapping and drying during cold weather.
Protect hands from cuts and scratches when performing household chores.
Patient Care Items
Instruments, devices, and equipment used to provide direct patient care become contaminated.
Appropriate infection-control measures must be taken to prevent transmission of infectious agents from patient to patient through these contaminated items.
Patient care items are either single-use disposable items or reusable items that require sterilization between uses.
Methods of appropriate infection-control measures include the following:
Cleaning, sterilization, or disinfection of reusable patient care items
Appropriate containment and disposal of all single-use items
Sterilization is the destruction of all living organisms, including highly resistant bacterial spores.
Properly performed cleaning and sterilization procedures offer the highest level of assurance that no pathogenic organisms remain on instruments and devices.
The intent of instrument and equipment sterilization is not to establish a sterile-care environment; rather, the sterilization process ensures the destruction of all organisms transferred to an item during use on a patient before reuse of the item on a subsequent patient.
Instrument Classification
Dental instruments fall into three broad categories for determining the minimal level of management between patients (Table 10.5):