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The importance of preventing infection
The importance of preventing infection Judy Scotter, Peter Davis LEARNING OUTCOMES On completion of the article the reader should be able to: 9 9 9
Describe the body's defence mechanisms against infection I m p l e m e n t protocols and guidelines to prevent infections and t h e i r spread Recognise the c o m m o n infections related to orthopaedic patients.
UKCC CATEGORIES This article will enable the reader to address PREP requirements through the following United Kingdom Central Council (UKCC) categories for professional development: 9 9 9
Care enhancement Practice development Reducing risk.
Examples of how this may be achieved, and possible evidence for the reader's professional profile are given t h r o u g h o u t the article. O t h e r ways to demonstrate your professional development may be through: 9 9 9 9
Reviewing the way you or your ward/unit minimise the risk of infection for your patients/clients Requesting your control of infection nurse to speak to a group of nurses you w o r k w i t h on current developments in infection control Asking a colleague to critically observe your own hand washing technique, at various times, w i t h o u t your knowledge and produce an action plan to improve it Keeping a copy of this article, any notes you may make as a result of reading it and the w o r k from the 'reflection items' in the text.
'Aspects of infection, such as pain, discomfort, embarrassment and worry, cannot be expressed in monetary terms, but can be very distressing for the relatives and nurses. Therefore any control measures that are successful in reducing infection must be worthwhile as well as being cost effective' (Bowell 1993 p 5). Judy Scotter, RGN, ONC, CertEd, BSc Senior Lecturer School of Health & Social Care South Bank UniversrLy London Peter Davis, MA, BEd(Hons), RN, ONC Principal Lecturer Redwood College of Health Studies South Bank University London Correspondence to: 24 Woodlands Road Hemel Hempstead Herts HP3 8RZ UK Tel/fax 01923 270757
INTRODUCTION Unfortunately, the development and presentation of an infection is not a new or unusual occurrence, Mason (1992) suggested that cross infection may be costing hospitals up to s million in extra care each year. There is no magic formula in preventing the spread of infection, precautions which need to be implemented should be based upon a knowledge of microbiology. This knowledge should then be used to form the basis of care planning or wound management protocols. Infection control guidelines allow for consistency of intervention that in turn
Journal of Ortha#aedicNursing (I 997) I, 2_09-2149 1997Harcourt Brace& Co Ltd
reduces confusion about standards of care, thereby minimising the potential for spread of infection.
FACTORS AFFECTING INDIVIDUALS' SUSCEPTIBILITYTO INFECTION Combinations of intrinsic and extrinsic factors play a vital role in determining how susceptible a person is to developing an infection (Table 1). For example, a person with rheumatoid arthritis may have the predisposing intrinsic factors of being elderly, on steroid treatment and have impaired immunological status. Predisposing extrinsic factors may then arise if they are admitted to hospital for joint replacement surgery, undergoing a change of environment and invasive procedures, and being inflicted with a wound, wound drainage and foreign bodies. These all decrease their ability to fight off harmful bacteria and leave them susceptible to developing an infection.
210 Journal of Orthopaedic Nursing
Intrinsic factors
Extrinsic factors
Age of patient Personal hygiene Nutritional status Immunologicalstatus Previous medicalhistory Metabolicdisorders Intake of drugs
Patient being in hospital ward Livingenvironment Contact with other people Resistance of micro-organism Route of spread of micro-organism
THE BODY'S DEFENCE MECHANISMS
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The normal healthy body has a number of mechanisms that effectively defend it from infection. Intact skin provides a barrier, the natural secretions have a bactericidal property and the normal skin flora prevents invasion by harmful bacteria. The flushing action of saliva removes microorganisms and the enzyme lysozyme acts as an antimicrobial agent. Hydrochloric acid in the stomach and bile in the duodenum destroy bacteria and mucus acts as a physical barrier. The normal flora such as Escherichia Coli acts to prevent colonlsation of other more harmful bacteria. Ciliated mucous membranes line the respiratory tract, bacteria are caught in the mucus and the beating of the cilia carry them up the airways. Hairs in the nostrils and the turbinal bones of the nose provide a barrier and the lymphoid tissue of the tonsils and adenoids fight potential infection. In a healthy person the bladder is a sterile organ, with just the tip of the urethra colonised by skin commensals. In women, vaginal pH of 4.5 prevents colonisation of bacteria. However, following the menopause, the vaginal epithelium produces less glycogen, the pH increases and reduced secretions lead to dryness all causing the vagina to become more easily inflamed and infected. Orthopaedic nurses should recognise how many of these natural barriers are breached when carrying out routine pre and postoperative procedures, see Reflection Item 1. The more breaches in the natural fines of defence, the more likely their patients are to develop an infection. As the patients' advocate they should question actions in areas such as wound management, removal of dressings and drains or the necessity to maintain intravenous lines. Urinary catheterisation is still frequently carried out in orthopaedic wards and the presence of a catheter provides direct access to the bladder for bacteria. Infection may also be introduced via the
catheter outlet if this touches the floor, or if the drainage system is disconnected or unwashed hands touch it. Urinary tract infections are the most common hospital acquired infections (Gould 1994, p 147). The insertion of an intravenous device is one of the most common invasive procedures; bacteria can migrate into the bloodstream from the skin along the cannula, from the hub or sideports of the cannula and from contaminated i.v. fluid. Infection may then present as local site infection, inflammation of the vein, bacteraemia and septicaemia or catheter colonisation. Prevention and early detection of infection is a vital aspect in caring for the patient with an intravenous infusion (Wilson 1994).
PREVENTING INFECTION
THE SPREAD OF
The spread of infection is dependant upon four factors known as the chain of infection: 9 The source of infection is the reservoir where micro-organisms thrive and multiply 9 The method of spread is the agent or route by which organisms spread from one point to another 9 The individual at risk in the hospital situation is the patient 9 The portal of entry is the break in the body's normal defence mechanism through which the organism gains entry. Prevention of the spread of infection can be achieved by breaking one of these links in the chain. Only through nurses having an adequate understanding of microbiology and infection control measures can this be achieved. Gould (1995) studied 130 nurses and concluded that most did not perform optimally in everyday nursing situations, nor did they have sufficient knowledge of microbiology to understand the theoretical principles underpinning infection control.
The importance of preventing infection
21 I
I. 2. 3. 4.
Preventpuncturewounds, cuts and abrasionsin the presence of blood and body fluids. Avoidthe use of or exposure to sharps when possible,but if unavoidable,take particularcare in handlingand disposal. Protect all breaks in exposed skinby means of waterproof dressingsand/or gloves. Protect the eyes and mouth by meansof a visor and goggles/safetyspectacles and a maskwhen splashingis a
5. 6. 7. 8. 9.
possibility. Avoid contamination of the person or clothing by use of waterproof/water-resistant protective clothing, plastic apron etc. Wear rubber boots or plastic disposable overshoes when the floor or ground is likely to be contaminated. Use good basic hygiene practices including hand washing and avoid hand to mouth/eye/etc contact. Control surface contamination by blood and body fluids by containment and appropriate decontamination procedures. Dispose of all contaminated waste safely.
H M S O (199S)
I. 2. 3. 4.
Selectionof resistantstrains. Changein gut flora, resultingin diarrhoea and pseudomembranouscolitis. Diagnosticconfusionif postoperative sepsis occurs. Increasedcosts. Sanderson (1988)
Nurses are in the unique position of providing intimate care for their patients, the standard of this care will have a direct effect on minimising the risks of patients developing hospital acquired infections. Vigilance needs to be maintained in ensuring that the universal precautions (Table 2) form their standards of care. Universal precautions were initially formulated to prevent cross infection from blood borne pathogens. There is no way of knowing which individual's bodily fluids present a high risk, therefore these precautions should be normal actions rather than something which is specifically implemented for certain patient groups. In so doing infection rates could be reduced. Patients should also be educated regarding infection control procedures and the responsibility they have in reducing cross infection.
P R E S E N T A T I O N OF I N F E C T I O N The presence of infection will give rise to certain systemic or localised signs. Systemic signs include pyrexia, tachycardia and tachypnoea, anorexia, nausea and vomiting, headache, joint and muscle pain and general malaise. The patient may be flushed, hot and the tongue may be dry and furred. Enlarged and tender lymph nodes may also be an indication of infection. Localised infection presents in the immediate area of infection, this is commonly a wound or joint. There will be redness, heat, swelling and pain. In the case of a wound infection there may be an associated discharge, inflammation and delayed healing or wound breakdown. Blood tests would show a raised erythrocyte sedimentation rate and a raised white cell count. These results should be read with caution as in the
early post operative phase they may simply indicate the body's normal physiological response tc surgery. Orthopaedic nurses need to be aware of these signs, but also develop the ability to use open endec questioning and active listening if the patient i~, expressing concerns about symptoms they may be feeling.
GENERAL INFECTIONS W o u n d infection Normal wound healing is a continuous process, clean, surgically incised wound will be sufficientl3 healed to allow the removal of sutures after seven t( ten days. Chronic or contaminated wounds, wil follow the same stages of healing-inflammation granulation, proliferation and maturation but caz take many months or years to fully mature. The duration and nature of chronic wounds giw them a greater potential for developing an infection and nurses need to be able to differentiate betweez the appearance of a wound at the inflammatou stage of healing, one which is infected and a chronic wound which is colonised with organisms. Gilchris (1994), differentiates between infection ant colonisation by considering the response of the hos to the invading organism. Diagnosis of a wounc infection should not be based upon swab results, bu the clinical presentation of the patient. Most nurse: would say that they were able to recognise wounc infection by observing for the well known signs o: inflammation. Cutting (1994) argues that if onl3 these signs are used patients may be discharged w i t unrecognised infections and suggests the addition o: some extra assessment criteria (Table 4), woulc enable a clearer picture to be obtained.
212 Journal of Orthopaedic Nursing
Traditional criteria I. Abscess 2. CeHulitis 3. Discharge (a) Serous exudate with inflammation (b) Seropurulent (c) Haemopurulent
(d) Pus
Suggested additional criteria 4. Delayed healing (compared with normal site/condition) 5. Discoloration 6. Friable granulation tissue which bleeds easily 7. Unexpected pain/tenderness 8. Pocketing at base of wound (a) Bridging at base of wound 9. Abnormal smell 10. Wound breakdown Cutting (1994)
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Patients in hospital are placed at a higher risk of developing an infection, Crowe (1996) reports the findings of a national survey which showed a mean hospital acquired infection rate of 9%. These infections fell into four main categories urinary tract infection (23.2%), lower respiratory tract infection (22.9%), surgical wound infection (10.7%) and skin infection (9.6%). Much of the available literature points to poor hand hygiene as a major causative factor. Gould (1991) suggested the poor positioning of sinks, unavailability of antiseptic solutions and lack of time to carry out the recognised hand washing procedure as contributory factors in the spread of infection, see Reflection Item 2.
SPECIFIC O R T H O P A E D I C INFECTIONS Acute osteomyelitis
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Acute haematogenous osteomyelitis presents in children with an average age of 7 to 8 years. The causative organism is usually staphylococcus aureus (75%), but in many cases the origin of infection is not discovered. The disease is uncommon in the western world with only approximately 20 cases a year being reported. (Goldschmidt & Hoffman 1991). Bacteria enter the bone via the blood stream, causing a focus of infection in the metaphysis, most commonly the upper end of tibia or lower end of femur. A build up of pus forces itself to the surface of the bone, stripping the periosteum and forming a subperiosteal abscess. The underlying bone, devoid of its blood supply dies and separates from the shaft forming the sequestrum. Osteoblastic activity lays down new bone, enclosing the affected area in an involucrum. Any remaining pus discharges through an individual sinus or through multiple smaller clocae.
The presentation of the disease includes fever, severe pain and protective muscle spasm, nonspecific signs such as these and the rarity of the condition may lead to a delay in diagnosis. A vigilant orthopaedic nurse should use observational skills and knowledge to help minimise a potentially devastating outcome.
Chronic osteomyelitis While acute osteomyelitis is uncommon in the adult, chronic osteomyelitis may present following a compound fracture that has been incompletely debrided at the time of reduction. Pozzi and Peck (1986) recognised it as the diagnosis most frequently identified in orthopaedic patients requiring long-term antibiotic therapy, prolonged treatment and repeated hospitalisation. Bacteria enter the bone and after initial treatment, lie dormant until a physiological incident causes them to multiply and present the patient with pain, redness, pyrexia swelling and a discharging sinus. These flare ups lead to immobility, loss of function, loss of independence through interruptions to work routines and loss of income through requiring time off for rest and medical treatment. Repeated courses of antibiotics, bedrest and hospital admissions are the only available options. Surgical interventions such as debridement, saucerisation and bone grafting have limited success in these cases and in severe instances elective amputation may be necessary.
Septic arthritis Septic arthritis may occur as the result of direct innoculation of bacteria into the joint or as a secondary complication of osteomyelitis. In a child, where the epiphyseal plate is intra-articular and epiphyseal fusion is incomplete, the invading bacteria may enter the joint and form a focus of infection in the synovial membrane. This leads to
The importance of preventing infection inflammation of the synovium, damage of the articular cartilage, death of affected tissue and pus formation within the joint. Clinical presentation will be of a hot, painful, swollen joint that is held in a position of fixed flexion with protective muscle spasm. Treatment includes apiration of the joint, intravenous antibiotics and rest, in some cases intraarticular antibiotics are a treatment of choice. As with osteomyelitis, if treated early, residual problems will be prevented. Delays can lead to bone and cartilage destruction causing alteration in bone growth, permanent joint damage and deformity or chronic sinus formation. The laying down of fibrous and bony tissue can lead to stiffness, deformity and loss of function.
Joint infection following arthroplasty As the average age of the population increases, more elderly individuals with disabling joint diseases may require total joint replacement to improve their quality of life. The development of a postoperative wound infection could lead to extended and costly hospitalisation and perhaps even result in permanent disability (Yandrich 1995). Many factors increase the risk of postoperative infection for an individual undergoing joint replacement. Good surgical technique is important in areas such as complete debridement of dead bone or old bone cement, thermal necrosis from equipment, the use of antibiotics and the choice of implant material. Nursing interventions relating to infection control in the peri-operative period should focus on adequately meeting the patient's hygiene needs, the administration of prescribed prophylactic antibiotic cover and the maintenance of an aseptic technique when dealing with post operative wounds. Gillespie (1994) acknowledges that in planned surgery, antibiotics should be administered at a time that will give levels above the expected minimum inhibitory concentration for likely pathogens throughout the operation. Most nurses will be familiar with a prophylactic regime of three doses of intravenous antibiotic administration. This supports early work of Sanderson (1988) who warns that continuing prophylaxis beyond a three dose regimen would appear to be a waste of antibiotic and may generate certain dangers (Table 3). Infection following joint replacement has the catastrophic potential results of loosening or rejection of the prosthesis, which may lead to permanent pain, deformity, immobility or the need to replace, or permanently remove, the prosthesis.
PIN SITE I N F E C T I O N The insertion of a metal pin for the application of skeletal traction or limb lengthening apparatus
213
provides a permanent open wound with the pin site conduit allowing access for bacteria into the bone and surrounding soft tissue. Much controversy arises regarding the management of pin tracts, especially those relating to limb lengthening apparatus. Nance and Mardjetko (1994) refer to a number of studies, which show differences in the use of cleansing agents, times of cleaning and whether or not scabs should be removed. A review by Rowe (1997) reinforces this controversy and recommends further research to compare the effectiveness of pin site care regimes for both external fixators and skeletal traction. Broader studies may lead to the development of national policies, but until then nurses should carefully read the available literature before making a decision relating to the optimal method of pin care.
M E T H IC I LLI N- RESI S T A N T STAPHYLOCOCCUS AUREUS All orthopaedic nurses will encounter methicillinresistant Staphylococcus aureus (MRSA) at some time. Humphreys and Duckworth (1997) identify orthopaedic and trauma wards as higher risk settings for MRSA. Staphylococcus aureus is commonly found on human skin, particularly moist areas such as the nasal mucosa, axilla, groin, perineum and toe webs. Up to 50% of people are nasal carriers of Staphylococcus aureus, although extra-nasal carriage is rare in healthy people (Noble 1981). Usually the organism is harmless but if it gains access to tissues beneath the skin via a wound or hair follicle it may cause infection. Strains of MRSA will have cross-resistance to all penicillin and cephalosporins. The only reliable treatment is vancomycin, which is expensive, has to be given intravenously and can be nephro- and hepatotoxic. It is only a matter of time before strains of Staphylococcus aureus emerge that are resistant to vancomycin. Most patients affected by MRSA will be colonised with the organism (Wilson & Richardson 1996). Few of those affected develop serious infection. However, colonised patients provide a reservoir from which there may be spread to other patients and more serious infections will occur. Control should be directed at limiting spread by detecting, isolating and treating patients colonised or infected with MRSA. Most guidelines aimed at reducing the risk to patients and health care staff are founded on maintaining good hygiene standards, see Reflection Item 3. Emphasis is on thorough hand-washing, appropriate use of protective clothing and complete cleaning and disinfection of the patient's environment.
214 Journal of Orthopaedic Nursing
CONCLUSION Nurses n e e d to b e continually aware o f Clause 2 in the Code o f Professional Conduct (UKCC, 1992) w h i c h states: 'Ensure that no action or omission on your part, or within your sphere o f responsibility is detrimental to the interests, condition or safety o f patients and clients'. Patients need to be educated regarding the responsibilities they have in minimising cross infection in the ward e n v i r o n m e n t and b e able to effectively care for their o w n wounds w h e r e possible.
REFERENCES
Bowell B 1993 Preventing infection and its spread. Surgical Nurse 5 - 12 Crowe M 1996 A plan for action to reduce hospital acquired infection. Nursing Times 92 (36): 40-41 Cutting K F 1994 Criteria for identifying wound infection. Journal of Wound Care 3 (4): 198-201 Gilchrist B 1994 Treating bacterial wound infection Nursing Times 90 (50): 55-58 Gillespie W 1994 Prophylaxis against infection in orthopaedic practice. Current Orthopaedics 8:220-225 Goldschmidt R, Hoffman E 1991 Osteomyelitis and septic arthritis in children. Current Orthopaedics 5:248-255 Gould D 1991 Nurses, hands as vectors of hospital acquired infection. Journal of Advanced Nursing 16:1215-1225
Gould D 1994 Preventing infection, promoting healing. In: Davis P (ed) Nursing the orthopaedic patient. Churchill Livingstone, Edinburgh HMSO 1995 Protection against blood-borne infections in the workplace: HIV and hepatitis. HMSO, London Humphreys H, Duckworth G 1997 Methicillin-resistant Staphylococcus aureus - a re-appraisal of control measures in light of changing circumstances. Journal of Hospital Infection 36:167-170 Nance D, Mardjetko S 1994 Technical aspects and nursing considerations of limb lengthening. Orthopaedic Nursing. 13 (1): 21--33 Noble WC 1981 Microbiology of human skin. Loyd & Luke, London Pozzi M, Peck N 1986 An option for the patient with chronic osteomyelitis: home intravenous antibiotic therapy. Orthopaedic Nursing 5 (5): 9-14 Rowe S 1997 A review of the literature on the nursing care of skeletal pins in the paediatric setting. Journal of Orthopaedic Nursing 1 (1): 26-29 Sanderson P J 1988 The choice between prophylactic agents for orthopaedic surgery. Journal of Hospital Infection 11: (Suppl C) 57-67 United Kingdom Central Council 1992 Code of Professional Conduct. United Kingdom Central Council for Nursing, Midwifery and Health Visiting. London Wiison J i994 Preventing infection during IV therapy. Professional Nurse 9 (6): 388-392 Wilson J, Richardson J 1996 Keeping MRSA in perspective. Nursing Times 92 (19): 58-60 Yandrich T 1995Preventing infection in total joint replacement surgery. Orthopaedic Nursing. 14 (2): 15-19
Describe the body's defence mechanisms against infection I m p l e m e n t protocols and guidelines to prevent infections and t h e i r spread Recognise the c o m m o n infections related to orthopaedic patients.
UKCC CATEGORIES This article will enable the reader to address PREP requirements through the following United Kingdom Central Council (UKCC) categories for professional development: 9 9 9
Care enhancement Practice development Reducing risk.
Examples of how this may be achieved, and possible evidence for the reader's professional profile are given t h r o u g h o u t the article. O t h e r ways to demonstrate your professional development may be through: 9 9 9 9
Reviewing the way you or your ward/unit minimise the risk of infection for your patients/clients Requesting your control of infection nurse to speak to a group of nurses you w o r k w i t h on current developments in infection control Asking a colleague to critically observe your own hand washing technique, at various times, w i t h o u t your knowledge and produce an action plan to improve it Keeping a copy of this article, any notes you may make as a result of reading it and the w o r k from the 'reflection items' in the text.
'Aspects of infection, such as pain, discomfort, embarrassment and worry, cannot be expressed in monetary terms, but can be very distressing for the relatives and nurses. Therefore any control measures that are successful in reducing infection must be worthwhile as well as being cost effective' (Bowell 1993 p 5). Judy Scotter, RGN, ONC, CertEd, BSc Senior Lecturer School of Health & Social Care South Bank UniversrLy London Peter Davis, MA, BEd(Hons), RN, ONC Principal Lecturer Redwood College of Health Studies South Bank University London Correspondence to: 24 Woodlands Road Hemel Hempstead Herts HP3 8RZ UK Tel/fax 01923 270757
INTRODUCTION Unfortunately, the development and presentation of an infection is not a new or unusual occurrence, Mason (1992) suggested that cross infection may be costing hospitals up to s million in extra care each year. There is no magic formula in preventing the spread of infection, precautions which need to be implemented should be based upon a knowledge of microbiology. This knowledge should then be used to form the basis of care planning or wound management protocols. Infection control guidelines allow for consistency of intervention that in turn
Journal of Ortha#aedicNursing (I 997) I, 2_09-2149 1997Harcourt Brace& Co Ltd
reduces confusion about standards of care, thereby minimising the potential for spread of infection.
FACTORS AFFECTING INDIVIDUALS' SUSCEPTIBILITYTO INFECTION Combinations of intrinsic and extrinsic factors play a vital role in determining how susceptible a person is to developing an infection (Table 1). For example, a person with rheumatoid arthritis may have the predisposing intrinsic factors of being elderly, on steroid treatment and have impaired immunological status. Predisposing extrinsic factors may then arise if they are admitted to hospital for joint replacement surgery, undergoing a change of environment and invasive procedures, and being inflicted with a wound, wound drainage and foreign bodies. These all decrease their ability to fight off harmful bacteria and leave them susceptible to developing an infection.
210 Journal of Orthopaedic Nursing
Intrinsic factors
Extrinsic factors
Age of patient Personal hygiene Nutritional status Immunologicalstatus Previous medicalhistory Metabolicdisorders Intake of drugs
Patient being in hospital ward Livingenvironment Contact with other people Resistance of micro-organism Route of spread of micro-organism
THE BODY'S DEFENCE MECHANISMS
Z 0 n
U r~ ul
..I
Z 0 m
U~
lu ii
0
13 Z
D Z m
FZ 0
U
The normal healthy body has a number of mechanisms that effectively defend it from infection. Intact skin provides a barrier, the natural secretions have a bactericidal property and the normal skin flora prevents invasion by harmful bacteria. The flushing action of saliva removes microorganisms and the enzyme lysozyme acts as an antimicrobial agent. Hydrochloric acid in the stomach and bile in the duodenum destroy bacteria and mucus acts as a physical barrier. The normal flora such as Escherichia Coli acts to prevent colonlsation of other more harmful bacteria. Ciliated mucous membranes line the respiratory tract, bacteria are caught in the mucus and the beating of the cilia carry them up the airways. Hairs in the nostrils and the turbinal bones of the nose provide a barrier and the lymphoid tissue of the tonsils and adenoids fight potential infection. In a healthy person the bladder is a sterile organ, with just the tip of the urethra colonised by skin commensals. In women, vaginal pH of 4.5 prevents colonisation of bacteria. However, following the menopause, the vaginal epithelium produces less glycogen, the pH increases and reduced secretions lead to dryness all causing the vagina to become more easily inflamed and infected. Orthopaedic nurses should recognise how many of these natural barriers are breached when carrying out routine pre and postoperative procedures, see Reflection Item 1. The more breaches in the natural fines of defence, the more likely their patients are to develop an infection. As the patients' advocate they should question actions in areas such as wound management, removal of dressings and drains or the necessity to maintain intravenous lines. Urinary catheterisation is still frequently carried out in orthopaedic wards and the presence of a catheter provides direct access to the bladder for bacteria. Infection may also be introduced via the
catheter outlet if this touches the floor, or if the drainage system is disconnected or unwashed hands touch it. Urinary tract infections are the most common hospital acquired infections (Gould 1994, p 147). The insertion of an intravenous device is one of the most common invasive procedures; bacteria can migrate into the bloodstream from the skin along the cannula, from the hub or sideports of the cannula and from contaminated i.v. fluid. Infection may then present as local site infection, inflammation of the vein, bacteraemia and septicaemia or catheter colonisation. Prevention and early detection of infection is a vital aspect in caring for the patient with an intravenous infusion (Wilson 1994).
PREVENTING INFECTION
THE SPREAD OF
The spread of infection is dependant upon four factors known as the chain of infection: 9 The source of infection is the reservoir where micro-organisms thrive and multiply 9 The method of spread is the agent or route by which organisms spread from one point to another 9 The individual at risk in the hospital situation is the patient 9 The portal of entry is the break in the body's normal defence mechanism through which the organism gains entry. Prevention of the spread of infection can be achieved by breaking one of these links in the chain. Only through nurses having an adequate understanding of microbiology and infection control measures can this be achieved. Gould (1995) studied 130 nurses and concluded that most did not perform optimally in everyday nursing situations, nor did they have sufficient knowledge of microbiology to understand the theoretical principles underpinning infection control.
The importance of preventing infection
21 I
I. 2. 3. 4.
Preventpuncturewounds, cuts and abrasionsin the presence of blood and body fluids. Avoidthe use of or exposure to sharps when possible,but if unavoidable,take particularcare in handlingand disposal. Protect all breaks in exposed skinby means of waterproof dressingsand/or gloves. Protect the eyes and mouth by meansof a visor and goggles/safetyspectacles and a maskwhen splashingis a
5. 6. 7. 8. 9.
possibility. Avoid contamination of the person or clothing by use of waterproof/water-resistant protective clothing, plastic apron etc. Wear rubber boots or plastic disposable overshoes when the floor or ground is likely to be contaminated. Use good basic hygiene practices including hand washing and avoid hand to mouth/eye/etc contact. Control surface contamination by blood and body fluids by containment and appropriate decontamination procedures. Dispose of all contaminated waste safely.
H M S O (199S)
I. 2. 3. 4.
Selectionof resistantstrains. Changein gut flora, resultingin diarrhoea and pseudomembranouscolitis. Diagnosticconfusionif postoperative sepsis occurs. Increasedcosts. Sanderson (1988)
Nurses are in the unique position of providing intimate care for their patients, the standard of this care will have a direct effect on minimising the risks of patients developing hospital acquired infections. Vigilance needs to be maintained in ensuring that the universal precautions (Table 2) form their standards of care. Universal precautions were initially formulated to prevent cross infection from blood borne pathogens. There is no way of knowing which individual's bodily fluids present a high risk, therefore these precautions should be normal actions rather than something which is specifically implemented for certain patient groups. In so doing infection rates could be reduced. Patients should also be educated regarding infection control procedures and the responsibility they have in reducing cross infection.
P R E S E N T A T I O N OF I N F E C T I O N The presence of infection will give rise to certain systemic or localised signs. Systemic signs include pyrexia, tachycardia and tachypnoea, anorexia, nausea and vomiting, headache, joint and muscle pain and general malaise. The patient may be flushed, hot and the tongue may be dry and furred. Enlarged and tender lymph nodes may also be an indication of infection. Localised infection presents in the immediate area of infection, this is commonly a wound or joint. There will be redness, heat, swelling and pain. In the case of a wound infection there may be an associated discharge, inflammation and delayed healing or wound breakdown. Blood tests would show a raised erythrocyte sedimentation rate and a raised white cell count. These results should be read with caution as in the
early post operative phase they may simply indicate the body's normal physiological response tc surgery. Orthopaedic nurses need to be aware of these signs, but also develop the ability to use open endec questioning and active listening if the patient i~, expressing concerns about symptoms they may be feeling.
GENERAL INFECTIONS W o u n d infection Normal wound healing is a continuous process, clean, surgically incised wound will be sufficientl3 healed to allow the removal of sutures after seven t( ten days. Chronic or contaminated wounds, wil follow the same stages of healing-inflammation granulation, proliferation and maturation but caz take many months or years to fully mature. The duration and nature of chronic wounds giw them a greater potential for developing an infection and nurses need to be able to differentiate betweez the appearance of a wound at the inflammatou stage of healing, one which is infected and a chronic wound which is colonised with organisms. Gilchris (1994), differentiates between infection ant colonisation by considering the response of the hos to the invading organism. Diagnosis of a wounc infection should not be based upon swab results, bu the clinical presentation of the patient. Most nurse: would say that they were able to recognise wounc infection by observing for the well known signs o: inflammation. Cutting (1994) argues that if onl3 these signs are used patients may be discharged w i t unrecognised infections and suggests the addition o: some extra assessment criteria (Table 4), woulc enable a clearer picture to be obtained.
212 Journal of Orthopaedic Nursing
Traditional criteria I. Abscess 2. CeHulitis 3. Discharge (a) Serous exudate with inflammation (b) Seropurulent (c) Haemopurulent
(d) Pus
Suggested additional criteria 4. Delayed healing (compared with normal site/condition) 5. Discoloration 6. Friable granulation tissue which bleeds easily 7. Unexpected pain/tenderness 8. Pocketing at base of wound (a) Bridging at base of wound 9. Abnormal smell 10. Wound breakdown Cutting (1994)
Z 0 m
Hospital acquired Infection u a m
l
Z 0
LU Lm
0 n,
D.
L) Z
Z
Patients in hospital are placed at a higher risk of developing an infection, Crowe (1996) reports the findings of a national survey which showed a mean hospital acquired infection rate of 9%. These infections fell into four main categories urinary tract infection (23.2%), lower respiratory tract infection (22.9%), surgical wound infection (10.7%) and skin infection (9.6%). Much of the available literature points to poor hand hygiene as a major causative factor. Gould (1991) suggested the poor positioning of sinks, unavailability of antiseptic solutions and lack of time to carry out the recognised hand washing procedure as contributory factors in the spread of infection, see Reflection Item 2.
SPECIFIC O R T H O P A E D I C INFECTIONS Acute osteomyelitis
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Acute haematogenous osteomyelitis presents in children with an average age of 7 to 8 years. The causative organism is usually staphylococcus aureus (75%), but in many cases the origin of infection is not discovered. The disease is uncommon in the western world with only approximately 20 cases a year being reported. (Goldschmidt & Hoffman 1991). Bacteria enter the bone via the blood stream, causing a focus of infection in the metaphysis, most commonly the upper end of tibia or lower end of femur. A build up of pus forces itself to the surface of the bone, stripping the periosteum and forming a subperiosteal abscess. The underlying bone, devoid of its blood supply dies and separates from the shaft forming the sequestrum. Osteoblastic activity lays down new bone, enclosing the affected area in an involucrum. Any remaining pus discharges through an individual sinus or through multiple smaller clocae.
The presentation of the disease includes fever, severe pain and protective muscle spasm, nonspecific signs such as these and the rarity of the condition may lead to a delay in diagnosis. A vigilant orthopaedic nurse should use observational skills and knowledge to help minimise a potentially devastating outcome.
Chronic osteomyelitis While acute osteomyelitis is uncommon in the adult, chronic osteomyelitis may present following a compound fracture that has been incompletely debrided at the time of reduction. Pozzi and Peck (1986) recognised it as the diagnosis most frequently identified in orthopaedic patients requiring long-term antibiotic therapy, prolonged treatment and repeated hospitalisation. Bacteria enter the bone and after initial treatment, lie dormant until a physiological incident causes them to multiply and present the patient with pain, redness, pyrexia swelling and a discharging sinus. These flare ups lead to immobility, loss of function, loss of independence through interruptions to work routines and loss of income through requiring time off for rest and medical treatment. Repeated courses of antibiotics, bedrest and hospital admissions are the only available options. Surgical interventions such as debridement, saucerisation and bone grafting have limited success in these cases and in severe instances elective amputation may be necessary.
Septic arthritis Septic arthritis may occur as the result of direct innoculation of bacteria into the joint or as a secondary complication of osteomyelitis. In a child, where the epiphyseal plate is intra-articular and epiphyseal fusion is incomplete, the invading bacteria may enter the joint and form a focus of infection in the synovial membrane. This leads to
The importance of preventing infection inflammation of the synovium, damage of the articular cartilage, death of affected tissue and pus formation within the joint. Clinical presentation will be of a hot, painful, swollen joint that is held in a position of fixed flexion with protective muscle spasm. Treatment includes apiration of the joint, intravenous antibiotics and rest, in some cases intraarticular antibiotics are a treatment of choice. As with osteomyelitis, if treated early, residual problems will be prevented. Delays can lead to bone and cartilage destruction causing alteration in bone growth, permanent joint damage and deformity or chronic sinus formation. The laying down of fibrous and bony tissue can lead to stiffness, deformity and loss of function.
Joint infection following arthroplasty As the average age of the population increases, more elderly individuals with disabling joint diseases may require total joint replacement to improve their quality of life. The development of a postoperative wound infection could lead to extended and costly hospitalisation and perhaps even result in permanent disability (Yandrich 1995). Many factors increase the risk of postoperative infection for an individual undergoing joint replacement. Good surgical technique is important in areas such as complete debridement of dead bone or old bone cement, thermal necrosis from equipment, the use of antibiotics and the choice of implant material. Nursing interventions relating to infection control in the peri-operative period should focus on adequately meeting the patient's hygiene needs, the administration of prescribed prophylactic antibiotic cover and the maintenance of an aseptic technique when dealing with post operative wounds. Gillespie (1994) acknowledges that in planned surgery, antibiotics should be administered at a time that will give levels above the expected minimum inhibitory concentration for likely pathogens throughout the operation. Most nurses will be familiar with a prophylactic regime of three doses of intravenous antibiotic administration. This supports early work of Sanderson (1988) who warns that continuing prophylaxis beyond a three dose regimen would appear to be a waste of antibiotic and may generate certain dangers (Table 3). Infection following joint replacement has the catastrophic potential results of loosening or rejection of the prosthesis, which may lead to permanent pain, deformity, immobility or the need to replace, or permanently remove, the prosthesis.
PIN SITE I N F E C T I O N The insertion of a metal pin for the application of skeletal traction or limb lengthening apparatus
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provides a permanent open wound with the pin site conduit allowing access for bacteria into the bone and surrounding soft tissue. Much controversy arises regarding the management of pin tracts, especially those relating to limb lengthening apparatus. Nance and Mardjetko (1994) refer to a number of studies, which show differences in the use of cleansing agents, times of cleaning and whether or not scabs should be removed. A review by Rowe (1997) reinforces this controversy and recommends further research to compare the effectiveness of pin site care regimes for both external fixators and skeletal traction. Broader studies may lead to the development of national policies, but until then nurses should carefully read the available literature before making a decision relating to the optimal method of pin care.
M E T H IC I LLI N- RESI S T A N T STAPHYLOCOCCUS AUREUS All orthopaedic nurses will encounter methicillinresistant Staphylococcus aureus (MRSA) at some time. Humphreys and Duckworth (1997) identify orthopaedic and trauma wards as higher risk settings for MRSA. Staphylococcus aureus is commonly found on human skin, particularly moist areas such as the nasal mucosa, axilla, groin, perineum and toe webs. Up to 50% of people are nasal carriers of Staphylococcus aureus, although extra-nasal carriage is rare in healthy people (Noble 1981). Usually the organism is harmless but if it gains access to tissues beneath the skin via a wound or hair follicle it may cause infection. Strains of MRSA will have cross-resistance to all penicillin and cephalosporins. The only reliable treatment is vancomycin, which is expensive, has to be given intravenously and can be nephro- and hepatotoxic. It is only a matter of time before strains of Staphylococcus aureus emerge that are resistant to vancomycin. Most patients affected by MRSA will be colonised with the organism (Wilson & Richardson 1996). Few of those affected develop serious infection. However, colonised patients provide a reservoir from which there may be spread to other patients and more serious infections will occur. Control should be directed at limiting spread by detecting, isolating and treating patients colonised or infected with MRSA. Most guidelines aimed at reducing the risk to patients and health care staff are founded on maintaining good hygiene standards, see Reflection Item 3. Emphasis is on thorough hand-washing, appropriate use of protective clothing and complete cleaning and disinfection of the patient's environment.
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CONCLUSION Nurses n e e d to b e continually aware o f Clause 2 in the Code o f Professional Conduct (UKCC, 1992) w h i c h states: 'Ensure that no action or omission on your part, or within your sphere o f responsibility is detrimental to the interests, condition or safety o f patients and clients'. Patients need to be educated regarding the responsibilities they have in minimising cross infection in the ward e n v i r o n m e n t and b e able to effectively care for their o w n wounds w h e r e possible.
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Bowell B 1993 Preventing infection and its spread. Surgical Nurse 5 - 12 Crowe M 1996 A plan for action to reduce hospital acquired infection. Nursing Times 92 (36): 40-41 Cutting K F 1994 Criteria for identifying wound infection. Journal of Wound Care 3 (4): 198-201 Gilchrist B 1994 Treating bacterial wound infection Nursing Times 90 (50): 55-58 Gillespie W 1994 Prophylaxis against infection in orthopaedic practice. Current Orthopaedics 8:220-225 Goldschmidt R, Hoffman E 1991 Osteomyelitis and septic arthritis in children. Current Orthopaedics 5:248-255 Gould D 1991 Nurses, hands as vectors of hospital acquired infection. Journal of Advanced Nursing 16:1215-1225
Gould D 1994 Preventing infection, promoting healing. In: Davis P (ed) Nursing the orthopaedic patient. Churchill Livingstone, Edinburgh HMSO 1995 Protection against blood-borne infections in the workplace: HIV and hepatitis. HMSO, London Humphreys H, Duckworth G 1997 Methicillin-resistant Staphylococcus aureus - a re-appraisal of control measures in light of changing circumstances. Journal of Hospital Infection 36:167-170 Nance D, Mardjetko S 1994 Technical aspects and nursing considerations of limb lengthening. Orthopaedic Nursing. 13 (1): 21--33 Noble WC 1981 Microbiology of human skin. Loyd & Luke, London Pozzi M, Peck N 1986 An option for the patient with chronic osteomyelitis: home intravenous antibiotic therapy. Orthopaedic Nursing 5 (5): 9-14 Rowe S 1997 A review of the literature on the nursing care of skeletal pins in the paediatric setting. Journal of Orthopaedic Nursing 1 (1): 26-29 Sanderson P J 1988 The choice between prophylactic agents for orthopaedic surgery. Journal of Hospital Infection 11: (Suppl C) 57-67 United Kingdom Central Council 1992 Code of Professional Conduct. United Kingdom Central Council for Nursing, Midwifery and Health Visiting. London Wiison J i994 Preventing infection during IV therapy. Professional Nurse 9 (6): 388-392 Wilson J, Richardson J 1996 Keeping MRSA in perspective. Nursing Times 92 (19): 58-60 Yandrich T 1995Preventing infection in total joint replacement surgery. Orthopaedic Nursing. 14 (2): 15-19