Chapter 12:
This chapter will review important information about clinical practice activities in the medical office. The topics include basic infection control procedures, treatments, and preparation of treatment areas. In addition, you will review patient history taking and strategies of assisting physicians with patient examination.
An important aspect of health care is to avoid doing harm to the patient. Infection control is critical to successful patient outcomes, as well as to your own health and well-being as a provider of care.
Infectious disease is caused by pathogens or agents. These pathogens are microorganisms or organisms that are too small to be seen without a microscope. Methods must be used to halt the transmission of these organisms in the medical office.
The spread of disease is dependent on a series of factors called the chain of infection. All of the links of this chain must be intact for infectious disease to spread. The goal of infection control is to stop the chain of infection from completing this series to prevent disease
The first link in the chain is the infective agent. The agent may be a virus, bacterium, protozoa, fungus, or rickettsia. The second link in the chain is the reservoir host. Potential hosts include contaminated people, insects, animals, food, water, or other objects including medical equipment. The reservoir host is where the pathogen resides prior to infecting a person. The third link is the portal of exit, which is how the agent leaves the host and spreads to another. The pathogen is then transmitted to the infected patient. Transmission (the fourth link) can occur with either direct or indirect contact. The pathogen might be expelled into the air from the host, transmitted by contaminated food or drink, or deposited on an inanimate object called a fomite. The pathogen is then picked up and deposited in the portal of entry. The pathogen may also be spread by a vector, which is an insect or animal that is capable of passing the pathogen on to a human host.
The portal of entry, the fifth link in the chain, could be the respiratory system, gastrointestinal system, reproductive system, or any open area in the skin of the susceptible host. The sixth link in the chain is a susceptible host. The pathogen must be able to survive in the environment of the host. Many different factors affect host susceptibility. If the host has immunity, the pathogen is not strong enough to fight the immune response of the host. If the host is not able to support the growth of the pathogen, the cycle will not complete. If there is no break in this chain, the cycle of infection will repeat itself over and over again. The actions that you take as a medical assistant are designed to prevent the spread of infection by breaking the links in this chain. Following is a list of examples of common pathogens and their methods of transmission to a susceptible host.
| Organism | Disease | Method of Transmission |
| Virus | HIV | Blood, body fluids |
| Bacterium | Neisseria gonorrhoeae (gonorrhea) | Sexual transmission |
| Fungus | Tinia (athlete's foot, ringworm) | Direct contact, clothing, moist environment |
| Protozoa | Malaria | Vector (Anopheles mosquito) |
| Rickettsia | Lyme disease | Vector (tick) |
There are several types of infection caused by the cycle of infection in humans.
Universal precautions are methods that are mandated by the Centers for Disease Control (CDC) to prevent the spread of infectious diseases in human populations. The CDC guidelines must be followed to protect the health and safety of the public and the health care worker. Universal precautions or standard precautions were first introduced in 1985 by the CDC in response to the concern about the spread of infectious disease and the safety of health care workers. Standard precautions are part the system of barrier precautions that are used with all patients regardless of their diagnosis by health care workers. These precautions include exposure to all blood, bodily fluids, skin that is not intact, and mucous membranes. Additionally, in July of 1992, the Occupational Safety and Health Administration (OSHA) began enforcing work practice controls in order to reduce or eliminate the risk of on-the-job exposure.
Potentially infectious body fluids include:
Barrier protection or personal protective equipment (PPE) must be available and worn when there is any possibility of contact with any of the listed body fluids. The type of PPE worn is dependent upon the possibility of contamination. Gloves must be worn at all times. Gown, eye protection, and masks are used if possible exposure is anticipated. As a result of the increase in use of latex gloves, there has also been an increase in the incidence of latex allergies. Hypersensitivity reactions to the latex or the powder in the gloves can cause localized reactions with dermatitis, urticaria, and rhinitis or systemic reactions such as anaphylaxis.
OSHA standards require that all employees who are at risk for exposure to blood-borne pathogens must be offered vaccination for hepatitis B free of charge by the employer. The vaccine is given in a series of three injections. Employees may refuse the vaccination, but must sign a declination form that the employer will maintain in their employee file. Employees can always receive the vaccine at a later date if they change their mind. The CDC recognizes that health care workers are at a higher risk of exposure to multiple diseases and recommends vaccination based on that exposure. Recommended precautions include MMR, Tdap, flu, and meningococcal vaccines, as described on the CDC website at https://www.cdc.gov/vaccines/adults/rec-vac/hcw.html.
OSHA also directs that certain procedures must be followed if there is a workplace exposure to body fluids. The procedures to manage the contamination include the following.
OSHA standards also apply to the disposal of biohazardous waste and specific housekeeping controls to make sure that your work areas are clean and maintained in a sanitary manner. Biohazardous waste includes any bodily fluid that comes from a patient, as well as any soiled or used equipment that came into contact with a patient. There must be a posted schedule of cleaning in work areas where there is possible exposure to biohazardous materials. Sharps containers must be used to contain waste such as glass, needles, scalpels, and syringes. These are rigid containers that must be sealed and disposed of properly by professional waste management companies. They may not be emptied by hand and should be monitored and changed before they become overly filled to prevent accidental injury. There must be a policy to clean biohazardous spills and materials to contain the spills for disposal. Garbage that is contaminated must be placed in a red bag marked with a biohazard sign and be disposed of by a specialized handler of biohazardous trash. It must be separated from noncontaminated trash to ensure it is taken care of in the correct manner and to keep costs down for the organization. It is much more expensive to dispose of contaminated waste than regular garbage. Soiled linens must be placed in an impervious bag without contaminating the surrounding area or your clothing. Gloves should always be worn when handling any item soiled with biohazardous waste.
Asepsis is the absence of infection or infectious material. Medical asepsis comprises the removal or destruction of pathogens after they leave the body. Examples of this are proper disposal of a soiled dressing into a red bag or a used sharp into a rigid biohazard container. Surgical asepsis is the removal or destruction of pathogens before they enter the body. Examples of this include the use of sterile instruments in a surgical procedure or a sterile syringe to give an injection.
The cornerstone of infection control is hand washing. Routine hand washing in the medical office is necessary before and after treating a patient, even if gloves are used.
The most important aspects are soap, friction, and warm, running water. Spend 1–2 minutes any time that contamination of the hands is apparent or suspected.
Hand washing for sterile procedures is even more involved and must be done for all sterile procedures (see Chapter 15).
The process of preparing instruments to be disinfected or sterilized is called sanitization. All blood and debris from the instruments must be removed prior to any further processing. You should wear thick gloves to prevent puncture by sharp instruments along with eye protection and a protective gown or lab coat to prevent soiling of clothing. Ultrasonic sterilization uses a special cleanser in a bath, which cleans the instruments with bubbles caused by sound vibrations. This is especially useful for delicate instruments that cannot be scrubbed and eliminates the need for handling of soiled instruments.
Disinfection is the process of killing or inactivating pathogens on objects. Environmental Protection Agency (EPA)–approved disinfectants can be purchased commercially or made fresh daily using a 1:10 solution of bleach and water. You must follow the manufacturer’s directions very carefully when using chemical disinfectants to ensure the best results possible. Disinfection also can be achieved by boiling materials that are able to withstand the temperature of 212°F for 15 minutes. This process will not sterilize. Ultraviolet radiation using ultraviolet light and desiccation or drying are other methods of disinfection.
Antiseptics are used on the skin. The most common is 70 percent alcohol, which is commonly used to clean the skin and to decrease the number of organisms at the site of injections. Betadine is also safe to use for antisepsis on skin, as long as the patient does not have an allergy to iodine.
Sterilization completely removes all microorganisms from objects. It can be done chemically, by autoclave, or by gas sterilization. Gas sterilization rarely takes place in the medical office. The method most often used in a medical office is the autoclave. Chemical sterilization is done using manufacturer specifications and must be used immediately after taking the item from the sterilization solution. The autoclave uses a combination of steam, heat, and pressure for a prescribed amount of time to sterilize different items. This method kills all organisms and spores.
Items to be sterilized in the autoclave must be wrapped in special disposable autoclave paper or packaged in special materials. Hinged instruments must be opened to allow steam to penetrate all areas of the item. Sharp points must be wrapped in gauze to prevent tearing of the protective packaging. If instruments are packaged in bags, the handle should be inserted first to be properly displayed for use when the package is peeled open. All packaging must include indicator strips to monitor the sterilization process and ensure that it was successful. Labeling with the name of the instrument, the date of sterilization, and the name of the person performing the procedure is necessary.
Sterilization indicators may be incorporated with the bags in which the instruments are packaged. Indicator strips are also used. They have special inks that become visible when the conditions for sterilization have been achieved. They should be placed in wrapped packs in order to determine that the steam has reached all areas of the pack. Finally, packs should be secured with autoclave tape, which will also turns colors when the appropriate conditions have been reached. Autoclaving should be done according to manufacturers’ directions. Control testing should be done in order to ensure that the autoclave is functioning properly.
Items that have been autoclaved are considered sterile for 28 days only. If the items have also been sealed in impervious plastic wrap, they will remain sterile for a longer period. The sterilized items must be stored properly and in a protected area. An item that has been autoclaved must be re-sterilized if the 28-day period has expired, the pack becomes wet, is dropped onto the floor, there is any tear in the packaging, or it is exposed to moisture. If there is any question about the integrity of the pack, it should be opened, the instruments re-cleaned, packed, and re-sterilized.