Case Studies in Infection
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Page updated 9 October 2006
Hand hygiene refers to the process for the physical removal of dirt, blood, body fluids and transient microorganisms from the hands (hand washing) and /or destruction of microorganisms (hand antisepsis). It is an important measure for preventing the spread of infection and is the cornerstone of good infection control. Direct contact is one of the main modes of transmission of the multi-drug resistant pathogenic bacteria MRSA or of viruses such as Herpes viruses, which cause cold sores and shingles. Even during simple contact such as shaking hands or touching a patients face bacteria and viruses are picked up on the hands. These transient bacteria, which do not become part of the dentist's normal resident bacterial hand flora, can persist for many hours unless they are removed. The microbes can be destroyed and the transmission of infection stopped, by the simple procedure of hand hygiene.
Correctly performed, hand hygiene will remove transient microorganisms from the surface of the skin. For routine dentistry it is not necessary to try and remove the resident bacterial flora, which have a symbiotic protective role. However, for surgical procedures (e.g. implant surgery) more extensive disinfection of the hands is required to reduce the numbers of resident bacteria.
Hand hygiene is divided into preparation, washing and rinsing, and drying. There is a science to hand washing/cleaning in the same way as there is to cleaning teeth effectively. Ayliffe's hand cleaning technique is shown in table? . This method of hand cleaning employs vigorous rubbing to create friction and ensures that all surfaces of the hands and wrists are exposed to the disinfectant and thoroughly cleaned in a systematic manner. It is suitable for applying alcoholic hand rub or hand washing with non-medicated soap and antiseptic handwash solutions. Hands washed with liquid soap or antiseptic handwash solutions should be thoroughly rinsed under running water. Completely drying the hands is a key factor in effective handwashing and maintaining skin integrity, as microorganisms can proliferate on damp hands and damaged skin.
Rings and watches prevent effective cleaning of the skin and should be removed. Gloves are more prone to tearing if rings are worn. Microbiological studies show that the skin under rings becomes heavily colonised with bacteria e.g. Staphylococcus aureus. Artificial nails and chipped nail polish may also harbour bacteria. Artificial nails have been implicated in outbreaks of bacterial and fungal infections in hospital wards. So it is best to keep fingernails short, clean and free from nail polish and artificial nails and jewellery (except wedding rings) should not be worn.
In preparation for dental treatment, hand hygiene should be carried out using a skin disinfectant preferably an alcohol based hand rub. Alcohol (gel /solution) hand rubs reduce the bacterial and viral load rapidly and are an effective alternative to handwashing for clean hands. Alcohol based hand rubs have the advantages of requiring no paper towels for drying, can be performed at the chair-side, and are less irritant to hands than soaps. Many products also incorporate a moisturiser.
Alcohol will not remove dirt or kill bacterial spores such as those of C. difficile . So dirty hands that are visibly soiled, or potentially grossly contaminated with dirt or organic material will need to be washed with liquid soap first. A non-medicated liquid soap removes dirt and transient microorganisms rendering hands socially clean. Alcohol hand gel can be used thereafter as long as hands remain visibly clean. Hand rubs are also available in an individual dispenser that can be carried in the pocket or a belt and are ideal were there is limited access to a sink such as on a domiciliary visit.
As may occur with any skin preparation, a small proportion of people can develop hypersensitivity to alcohol based hand rubs. Affected staff should change to an alternative product and seek medical advice from Occupational Health or their GP. Alcohol is flammable and care should be taken to avoid contact with direct heat or sunlight, especially when it is stored in bulk. As is the case with all disinfectants a COSHH assessment must be undertaken. Keep it out of reach of children who might be tempted to drink it!
Hand antisepsis is indicated prior to minor oral surgery, periodontal and implant surgery and aims to remove transient microorganisms and reduce resident microorganisms. It requires a more time intensive technique using aqueous antiseptic or alcohol solution. Hands are washed with antiseptic handwash solution (Chlorhexidine (Hibiscrub), Povidine -iodine (Betadine) or Triclosan (Aquasept) or equivalent) for 2 minutes. Alternatively use an alcohol hand rub. T wo x 5ml applications of alcohol rub solution can be applied to socially clean hands that have been washed with soap and water. Rub hands and wrists using the method described above until completely dry .
Staff who have an existing skin conditions such as dermatitis or who develop skin irritation with a particular product should seek expert advice on treatment and management.
Intact skin is a barrier to infection, so it is essential that you take care of your hands and wear heavy duty gloves for work in the home and garden. Soaps and disinfectants cause drying and abrasion of the hands, which in some cases can lead to an irritant dermatitis. In order to avoid these problems apply hand cream several time a day. Hand cream has been shown to reduce cross infection by preventing shedding of residential bacteria. Do not use petroleum based products as they can weaken the latex and increase glove permeability.
Avoid sharing communal pots of hand cream as these can become contaminated. Use individual supplies or pump dispensers of hand cream.