Handwashing practices in the patient care setting began in the early 19th century. The practice evolved over the years with evidential proof of its vast importance and coupled with other hand-hygienic practices, decreased pathogens responsible for nosocomial or hospital-acquired infections (HAI). [1][2][3]

Contaminated hands of healthcare providers are a primary source of pathogenic spread. Proper hand hygiene decreases the proliferation of microorganisms, thus reducing infection risk and overall healthcare costs, length of stays, and ultimately, reimbursement.

According to the Centers for Disease Control and Prevention (CDC), hand hygiene is the single most important practice in the reduction of the transmission of infection in the healthcare setting[4][2]. Despite this evidence, studies have repeatedly shown that the importance of hygiene has not been adequately recognized amongst healthcare professionals and compliance remains low [5]. 

According to the CDC, understanding the importance of hand hygiene and its impact on the pathogenic spread of microorganisms is best understood when one understands the anatomy of the skin. The skin serves as a protective barrier against water loss, heat loss, microorganisms, and other environmental hazards.[6]

Structurally, the skin is made up of an outer, superficial layer known as the stratum corneum, the epidermis, dermis, and the hypodermis. Healthy skin is colonized with resident flora that are microorganisms that reside below the stratum corneum and the skin's surface [7]. This flora has two main functions: microbial antagonism and competing for nutrients within the ecosystem. Generally, these bacteria are not pathogenic on intact skin but may cause infections in other areas of the body such as nonintact skin, the eyes, or sterile body cavities [7]. 

Transient microorganisms are often acquired by healthcare workers through direct, close contact with patients or contaminated inanimate objects or environmental surfaces. Transient flora colonizes the superficial skin layers [8]. It can be removed by routine handwashing more easily than resident flora. These organisms vary in number depending upon body location. Healthcare-associated infections are a result of these transient organisms.[9][10][11][12]

According to the CDC, hand hygiene encompasses the cleansing of your hands with soap and water, antiseptic hand washes, antiseptic hand rubs such as alcohol-based hand sanitizers, foams or gels, or surgical hand antisepsis. Indications for handwashing include when hands are visibly soiled, contaminated with blood or other bodily fluids, before eating, and after restroom use. Hands should be washed if potential there was potential exposure to Clostridium difficile, Norovirus, or Bacillus anthracis.[13][14]

In 2009, the World Health Organization (WHO) highlighted preset guidelines known as the "Five Moments for Hand Hygiene." [15]

1. Before touching or coming into contact with a patient
2. Before performing a clean or aseptic procedure
3. After an exposure risk to bodily fluids and glove removal
4. After contact with a patient and their immediate surroundings
5. After touching an inanimate object in the patient's immediate surroundings even if no direct patient contact

Alcohol-based hand sanitizers are the recommended product for hand hygiene when hands are not visibly soiled. Apply alcohol-based products per manufacturer guidelines on dispensing of the product. Typically, 3 mL to 5 mL in the palm, rubbing vigorously, ensuring all surfaces on both hands get covered, about 20 seconds is required for all surfaces to dry completely [15].

Patient and facility healthcare professionals are monitored for hand-washing practices, and they are conforming to hand-hygiene practices. This practice is becoming increasingly popular as healthcare professionals strive for a safer environment.

Artificial nails and nail extensions contain pathogens in the subungual spaces; thus posing a threat to microorganism transmission in the healthcare arena. Therefore, it is recommended that healthcare professionals do not use them. Well-manicured nails and adherence to artificial nail policies outlined in facility-specific guidelines are vital to hand hygiene practices. The WHO guidelines recommend that nails should be kept less than 0.5cm long [15]. 

Hand rubbing with an alcohol-based rub should not be performed when the hands are visibly soiled. In this case, the CDC and WHO guidelines recommend that handwashing with soap and water [15].

Handwashing is the act of washing hands with soap, either antimicrobial or nonantimicrobial, and water for at least 15 to 20 seconds with a vigorous motion to cause friction making sure to include all surfaces of the hands and fingers.

It requires a specific skill set to ensure proper technique. 

Handwashing Technique: [15]

• Begin by standing in front of the sink and taking care not to touch sink surfaces with hands or uniform/lab coat.
• If hands touch sinks at any time during this process, they are considered contaminated, and you must start the process over.
• Turn on the warm water. Allow water to wet hands and wrists thoroughly.
• Remember to keep hands and forearms lower than your elbows, so cross-contamination from water running back does not occur.
• Water should flow in a manner from least to most contaminated areas such as the hands. Microorganisms get washed down the sink. 
• Apply approximately 3 mL to 5 mL of an antiseptic soapy solution. Soap requires even distribution with a nice lather making sure all areas of hands receive covering in soap. 
• Next, use friction or rubbing of hands and wrists for no less than 15-20 seconds to ensure the removal of germs.
• Use a timer or timed sink if available.
• This vigorous rubbing of hands and wrists will include anterior and posterior surfaces, cuticle area, underneath nails, and in between each finger.
• Leave no part of the hand or wrist untouched.
• Interlace fingers, rub palms and backs of hands at least five times each to ensure all areas have coverage. 
• The World Health Organization (WHO) recommends 6 steps in hand hygiene. This includes palm to palm, right palm over the left dorsum and vice versa, palm to palm with fingers interlaced, backs of fingers to opposing palms, rubbing of thumbs and fingertips.
• Rinse hands and wrists making sure all soap has been successfully washed off.
• When rinsing off water remember to keep hands down and elbows up, then dry hands and wrists entirely with clean or disposable towels.
• Throw towels away if disposable or place in the appropriate place/hamper/bin without coming into contact with these objects.
• The end of handwashing will involve making sure you do not recontaminate your hands by touching the sink or faucet handles to turn the water off. Once hands are washed and dried, use a towel to turn off the water and then dispose of it in the appropriate container. 
• Surgical sinks/handwashing stations have timers such as in trauma bays that automatically shut off at specific time intervals. These guard against recontamination of hands/wrists by ensuring there is no need to turn the water off manually.