Chapter 4 Infection prevention and control Pat Cattini with Martin Kiernan STERILE HAND WASHING C. DIFFICILE VIRUS DECONTAMINATION INFECTION MICROBIOLOGY THOGENS CLEANLINESS PA HCAI ISOLATION E. COLI SCRUB The Royal Marsden Manual of Clinical Nursing Procedures: Professional Edition, Tenth Edition. Edited by Sara Lister, Justine Hofland and Hayley Grafton. © 2020 The Royal Marsden NHS Foundation Trust. Published 2020 by John Wiley & Sons Ltd. 0004519863.INDDChapter 64 No.: 3 Title Name: <TITLENAME> 0004519863.INDD09-03-2020 15:43:49 Comp. by: <USER> Date: 09 Mar 2020 Time: 03:43:49 pm Stage: <STAGE> WorkFlow:<WORKFLOW> Page Number: 64 Procedure guidelines 4.1 Hand washing 79 4.11 Aseptic technique example: changing a wound 4.2 Hand decontamination using an alcohol-based handrub 80 dressing 102 4.3 Surgical scrub technique using soap and water 82 4.12 Source isolation: preparing an isolation room 106 4.4 Surgical scrub technique using an alcohol-based 4.13 Source isolation: entering an isolation room 107 handrub 84 4.14 Source isolation: leaving an isolation room 108 4.5 Putting on and removing non-sterile gloves 88 4.15 Source isolation: transporting infected patients outside a 4.6 Applying and removing a disposable apron 89 source isolation area 108 4.7 Putting on and removing a disposable mask or 4.16 Protective isolation: preparing an isolation room 109 respirator 91 4.17 Protective isolation: entering an isolation room 110 4.8 Putting on or removing goggles or a face-shield 93 4.18 Cleaning a hard surface without recontamination 112 4.9 Donning a sterile gown and gloves: closed technique 94 4.19 Safe disposal of foul, infected or infested linen 117 4.10 Donning sterile gloves: open technique 98 Being an accountable professional At the point of registration, the nurse will: 9. Use evidence-based, best practice approaches for meeting capacity for independence and self-care and initiating needs for care and support with the prevention and appropriate interventions. management of infection, accurately assessing the person’s Future Nurse: Standards of Proficiency for Registered Nurses (NMC 2018) 0004519863.INDDChapter 65 No.: 3 Title Name: <TITLENAME> 0004519863.INDD09-03-2020 15:43:49 Comp. by: <USER> Date: 09 Mar 2020 Time: 03:43:49 pm Stage: <STAGE> WorkFlow:<WORKFLOW> Page Number: 65 The Royal Marsden Manual of Clinical Nursing Procedures Overview This chapter begins with an explanation of the causes of infection and then focuses on healthcare-associated infections (HCAIs), specifically describing the steps to be taken to minimize the risk of Susceptible Portal of individuals acquiring infections while receiving healthcare. The host entry 66 chapter gives an overview of key principles, terminology and defi- nitions, and describes the standard precautions that must be Infectious taken with patients at all times regardless of their known infection agent Transmission status. It also covers additional precautions that may be required because the patient is colonized or infected with micro-organisms that may pose a particular risk to others, or because they are par- Reservoir Portal of ticularly vulnerable to infection themselves. The chapter addition- exit ally describes the specific precautions that must be taken during invasive procedures, in particular aseptic technique. Figure 4.1 The chain of infection: a useful tool for seeing how to prevent transmission. Infection prevention and control Definitions Some of these distinctions are still useful, but classification is increasingly based on genetic characteristics, as increasingly Infection prevention and control sophisticated analysis techniques (such as genomic sequencing) ‘Infection prevention and control’ has been defined as the clinical reveal the actual relationships between organisms. This can lead application of microbiology in practice (RCN 2017); it is a collec- to confusion as new discoveries lead to species being reclassified tive term for activities intended to protect people from infection. and renamed. For example, ‘methicillin-resistant’ Staphylococcus Such activities may form part of everyday life, such as washing aureus is now ‘meticillin-resistant’ and Clostridium difficile is now hands after using the toilet or before preparing food. However, the termed Clostridioides difficile. term is most often used in relation to healthcare, with reference in It should also be noted that there can be a wide variety of char- particular to avoiding patients acquiring preventable infections. acteristics within each species, leading to significant variations in the severity of infection caused by different strains of the same Healthcare-associated infection organism. An example of this is Group A Streptococcus pyogenes, A healthcare-associated infection (HCAI) is any infection acquired which is a common cause of sore throat but can also cause skin as a result of healthcare contact. It has replaced the term ‘hospital- conditions such as erysipelas, scarlet fever, toxic shock syndrome acquired infection’ to recognize that not all healthcare is given in a and necrotizing fasciitis. Another is Escherichia coli, which is car- hospital. Such infections are also known as ‘nosocomial’ infections. ried in the gut of all mammals with no ill effects but whose toxin- producing O157:H7 strain can cause serious illness. Anatomy and physiology In printed text, the names of bacteria are written in italics, with Pathogens are what cause infection. It is important to understand the name of the genus capitalized and the species in lower case, types of pathogen, how they spread and what kinds of environ- for example Staphylococcus aureus. The abbreviation ‘spp.’ is used ment are favourable for their growth so that effective infection pre- to refer to all of the species of a genus, for example Klebsiella spp. vention and control measures can be put in place. This section gives an overview of the different types of organism that may be encountered in a healthcare environment as well as Causes of infection the differences between and within the types. The term ‘infectious agent’ is often used to describe anything that may be transmitted from one person to another, or from the envi- Bacteria ronment to a person, and subsequently cause an infection or para- Bacteria are probably the most important group of micro-organisms sitic infestation. in terms of infection prevention and control because they are Distinct types of infectious agent act differently and have differ- responsible for the majority of opportunistic infections in health- ent impacts on the infected individual. For example, whether a care. A healthy human being will typically be host to a quadrillion particular infectious agent will cause an infection in any given cir- (1000 trillion or 1015) bacteria – around ten times as many organ- cumstance is dependent on many factors, including how easily isms as there are cells in the human body – and we need most of that agent can be transmitted, its pathogenicity (its ability to cause these to survive. disease) and its virulence (the severity of the infection produced) The so-called ‘human microbiome’ is increasingly being recog- (Gillespie and Bamford 2012). The susceptibility of the patient to nized as an essential part of human health (Bhalodi et al. 2019, infection is also a significant influence. Young 2017) and a variety of conditions – such as Crohn’s disease, To practice effective infection prevention and control, it is helpful ulcerative colitis, irritable bowel syndrome, obesity, type 2 diabe- to understand the ‘chain of infection’ (Damani 2011). This is a help- tes, Parkinson’s disease, chronic fatigue syndrome, arthritis and ful model to use when considering how infection can be prevented, even asthma – may all be related to disturbance of the balance of as it shows how it is possible to break the ‘links’ in the chain. For an micro-organisms in the gut, although the question remains as to infection to exist, there must be an organism (pathogen) and it must whether this is a cause or effect (Otter 2014, Tosh and McDonald be able to get into a susceptible host, multiply and exit. It may need 2012, Wang et al. 2017). See Table 4.2 for examples of how the a place to hide (reservoir) while waiting for the next susceptible human microbiome can be protective. host. Figure 4.1 illustrates the chain of infection and Table 4.1 lists In normal circumstances, the relationship between bacteria and the links with examples of how infection can be prevented at each their host is symbiotic and the organisms are considered to be link. The major groups of micro-organisms are described below. commensal (i.e. their presence does not cause the host any prob- lems) and mutually beneficial; however, if the host has lowered Types and classification of micro-organisms resistance or a bacteria gains access to a different site, it can Historically, the classification of micro-organisms was based on become an opportunistic pathogen. For example, E. coli from the physical characteristics such as their size, shape or ability to retain gut may cause a urinary tract infection (with associated symp- a particular stain to make them visible under the microscope. toms) if it enters the urethra and ascends the urinary tract. 0004519863.INDDChapter 66 No.: 3 Title Name: <TITLENAME> 0004519863.INDD09-03-2020 15:43:50 Comp. by: <USER> Date: 09 Mar 2020 Time: 03:43:49 pm Stage: <STAGE> WorkFlow:<WORKFLOW> Page Number: 66 Chapter 4 Infection prevention and control Table 4.1 Links in the chain of infection Link Definition