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B1.7 Aseptic Technique
Aseptic technique protects patients during invasive clinical procedures by employing infection control measures that minimise, as far as
practicably possible, the presence of pathogenic microorganisms.
B1.7.1 Aseptic non-touch technique (ANTT)
ANTT is a framework for aseptic practice — the principles are intended for use in a range of settings from the operating theatre to the
community. Since 1993, the ANTT project (www.antt.org.uk) has helped implement ANTT through clinical guidelines and a standard
implementation process, into hundreds of hospitals and community health organisations in the UK and internationally. As a result, ANTT has
become the first standardised method of aseptic technique to exist in multiple hospitals and community care organisations. Hospitals that have
implemented ANTT robustly have reported significant improvements in practice that have helped reduce rates of healthcare-associated infection
(Rowley & Clare 2009).
Terminology
Historically, the practice of protecting patients from contamination and infection during clinical procedures has generated an inaccurate and
confusing paradigm based on the terminology of undefined sterile, aseptic and clean techniques.
The use of accurate terminology is important in order to promote clarity in practice.
Sterile
‘Free from microorganisms’ (Weller 1997)
Due to the natural multitude of organisms in the atmosphere it is not possible to achieve a sterile technique in a typical healthcare setting. Near
sterile techniques can only be achieved in controlled environments such as a laminar air flow cabinet or a specially equipped theatre. The
commonly used term, ‘sterile technique’ i.e. the instruction to maintain sterility of equipment exposed to air, is obviously not possible and is often
applied inaccurately.
Asepsis
‘Freedom from infection or infectious (pathogenic) material' (Weller 1997)
An aseptic technique aims to prevent pathogenic organisms, in sufficient quantity to cause infection, from being introduced to susceptible sites
by hands, surfaces and equipment. Therefore, unlike sterile techniques, aseptic techniques are possible and can be achieved in typical hospital
and community settings.
Clean
‘Free from dirt, marks or stains’ (Mcleod 1991).
Although cleaning followed by drying of equipment and surfaces can be very effective it does not necessarily meet the quality standard of asepsis
(Ayliffe 2000). However, the action of cleaning is an important component in helping render equipment and skin aseptic, especially when there
are high levels of contamination that require removal or reduction. However, to be confident of achieving asepsis an application of a skin or hard
surface disinfectant is required either during cleaning or afterwards.
Consequently, the aim of any aseptic technique including ANTT, is asepsis.
ANTT in practice
ANTT is a technique used to prevent contamination of key parts and key sites by microorganisms that could cause infection. In ANTT, asepsis is
ensured by identifying and then protecting key parts and key sites by hand hygiene, non-touch technique, using new sterilised equipment and/or
cleaning existing key parts to a standard that renders them aseptic prior to use (Rowley et al 2010).
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Risk assessment
While the principles of ANTT remain constant for all clinical procedures, the level of practice will change depending upon a standard ANTT risk
assessment. Taking into account the technical difficulty of the procedure and his or her own competence, the healthcare worker assesses
whether procedures can be performed without touching key parts and key sites directly. Infective precautions are then selected to counter the
risks identified. For example, if it were necessary to touch a key part directly, sterile gloves would be the gloves of choice. Otherwise non-sterile
gloves would be used.
B1.7.2 Core infection control components of ANTT
Key part and key site identification and protection
Key parts must be identified and protected at all times. Aseptic key parts must only come into contact with other aseptic key parts and/or key
sites.
Hand hygiene
Effective hand hygiene is an essential component of ANTT. In Standard ANTT, hand hygiene should be performed as outlined in Section B1.1. In
Surgical ANTT, a surgical hand scrub is required (ICNA 2002) (see Section B4.3.2).
It is known that hand hygiene is not always correctly performed and that even correctly performed hand hygiene cannot always remove all
pathogenic organisms. Therefore, a non-touch technique — identifying ‘key parts’ and not touching them directly or indirectly — is a vital
component of achieving asepsis. In other words, the safest way to protect a key part is not to touch it, even when wearing sterile gloves, as even
sterile gloves can become contaminated.
Glove use
Gloves are single-use items. In ANTT, if it is necessary to touch key parts or key sites directly, sterile gloves are used to minimise the risk of
contamination. Otherwise, non-sterile gloves are typically the gloves of choice.
Aseptic fields
Even well cleaned hospitals can be said to be ‘dirty’ — busy and dynamic environments resident with unusual antibiotic-resistant organisms.
Consequently, aseptic fields are important in providing a controlled aseptic working space to help promote or ensure the integrity of asepsis
during clinical procedures. It is also important that aseptic fields are fit for purpose. In ANTT, aseptic fields are increased in size and sterilised
drapes added on the basis of procedure complexity; for example in IV therapy, ‘mobile’ aseptic fields such as plastic trays should be large enough
and with high sides to provide an adequate working space to contain equipment, sharps and spillages.
ANTT employs two types of aseptic field that require different management depending on whether the primary purpose is to promote or ensure
asepsis.
Critical aseptic fields; ensuring asepsis
Critical aseptic fields are used when key parts and/or key sites, usually due to their size or number, cannot easily be protected at all times with
covers and caps, or handled at all times by a non-touch technique (such as in PICC line, urinary catheter insertion, complex wound care etc), or
when particularly open and invasive procedures demand large aseptic working areas for long durations, as in the operating room. In such cases,
the critical aseptic field demands to be managed as a key part (i.e. only equipment that has been sterilised can come into contact with it). Such a
critical aseptic field demands the use of sterilised gloves and, often, full barrier precautions (Pratt et al 2007). Large main critical aseptic fields
are used in Surgical ANTT and as a result, technique is more complicated.
A sub-type of a main critical aseptic field is the critical micro aseptic field. Traditional non-touch/clean techniques have protected key parts by
syringe caps, sheathed needles, covers or packaging etc. This often-understated approach is given new emphasis in ANTT, because the inside of
such caps and covers have been sterilised and thus provide an optimum all-encompassing aseptic field for key parts.
General aseptic fields; promoting asepsis
General aseptic fields are used in Standard ANTT when key parts can easily and optimally be protected by critical micro aseptic fields and a nontouch technique. The main general aseptic field does not have to be managed as a key part and is essentially promoting rather than ensuring
asepsis. Subsequently, aseptic technique is considerably simplified and typically involves non-sterile gloves.
Figure B1.4: Use of standard and surgical aseptic non-touch technique
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Environmental control
Prior to aseptic procedures, healthcare workers must ensure that there are no avoidable nearby environmental risk factors, such as bed making
or patients using commodes.
Sequencing
ANTT practice is sequenced to ensure an efficient, logical and safe order of procedure events. Section B5.4 provides examples of how to perform
ANTT for peripheral and central access intravenous therapy and for wound care.
B1.7.3 Surgical or Standard ANTT?
Differentiation between Standard and Surgical ANTT is intended to provide clarity and structure to aid understanding, but not polarise practice.
ANTT guidelines help standardise practice, technique and equipment levels.
Standard ANTT — Clinical procedures managed with Standard ANTT will characteristically be technically simple, short in duration
(approximately less than 20 minutes), and involve relatively few and small key sites and key parts. Standard ANTT requires a main general
aseptic field and non-sterile gloves. The use of critical micro aseptic fields and a non-touch technique is essential to protect key parts and
key sites.
Surgical ANTT — Surgical ANTT is demanded when procedures are technically complex, involve extended periods of time, large open key
sites or large or numerous key parts. To counter these risks, a main critical aseptic field and sterile gloves are required and often full
barrier precautions (Pratt et al, 2007). Surgical ANTT should still utilise critical micro aseptic fields and non-touch technique where
practical to do so.
Table B1.16: Use of aseptic non-touch technique for specific procedures
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Procedure Standard Rationale/typical procedure
/Surgical
ANTT
IV therapy
Standard ANTT
Key parts can typically be protected by optimal critical micro fields and non-touch technique.
Key sites are small. Procedures are technically simple and <20 mins duration.
Simple wound
dressings
Standard ANTT
Key parts and sites can be protected by optimal critical micro fields and non-touch technique.
Procedures are technically simple and <20 mins duration.
Complex or large
wound dressings
Surgical ANTT
The complexity, duration or number of key parts may demand a critical aseptic field.
Urinary
catheterisation
Standard/
An experienced healthcare worker can perform catheterisation with the use of a main general
aseptic field, micro-aseptic-fields and a non-touch technique. However, less experienced
healthcare workers may require a critical aseptic field.
Surgical ANTT
Cannulation
Standard/
Surgical ANTT
Although technically quite simple the close proximity of healthcare worker hands to the
puncture site and key parts may demand sterile gloves – dependant upon healthcare worker
competency.
PICC/CVC insertion
Surgical ANTT
The size of the CVC or PICC line, invasiveness, numerous key parts and equipment and duration
will demand a critical aseptic field and full barrier precautions.
Surgery
Surgical ANTT
Surgical access involves deep or large exposed wounds, numerous key parts and equipment and
long procedures. Standard operating room precautions required.
B1.7.4 References
Ayliffe G, Fraise A, Geddes A, Mitchell K (2000) Control of Hospital Infection: A Practical Handbook. 4th edition. Butterworth Heinemannn,
Oxford.
Cotterill S, Evans R, Fraise AP (1996) An unusual source for an outbreak of MRSA on an intensive care unit. J Hospital Infect 32(3): 207–16.
Kaler W & Chinn R (2007) A Matter of time and friction. JAVA 12(3): 140–42.
ICNA (2002) Hand Decontamination Guidelines. Infection Control Nurses Association. Available from [email protected]
McLeod W (1991) The New Collins Dictionary and Thesaurus. Harper Collins Publishers, Glasgow.
Pratt RJ, Pellowea CM, Wilson JA et al (2007) epic2: National Evidence-Based Guidelines for Preventing Healthcare-Associated Infections
in NHS Hospitals in England. J Hospital Infect (2007) 65S, S1–S64
Roberts K, Smith C, Snelling A et al (2008) Aerial dissemination of clostridium difficile spores. BMC Infectious Diseases 8(7). Available:
www.biomedcentral.com/1471-2334/8/7.
Rowley S & Clare S (2009) Improving standards of aseptic practice through an ANTT trust-wide implementation process: a matter of
prioritisation and care. Brit J Infection Prevention 10(1): IV Supplement.
Rowley S, Clare S, Macqueen A et al (2010) ANTTv2 An updated practice framework for aseptic technique. Brit J Nursing 19(5).
Weller B (ed) (1997) Encyclopedic Dictionary of Nursing and Health Care. Balliere Tindall, London: 81.
Source URL (modified on 05/10/2010 - 10:19): https://www.nhmrc.gov.au/book/australian-guidelines-prevention-and-control-infectionhealthcare-2010/b1-7-aseptic-technique
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