practice
Wound swab use and misuse at a regional general hospital Objective: Guidelines for swab use at our centre cover lower-limb wounds, ulcers and postoperative wound infections but not all types of wound. The objective of this study was to assess current practices in wound management at Mater Dei Hospital and to identify areas for improvement. l Method: Wound swabs received at the microbiology department between February and April 2013 from adult inpatients departments were included.Wound swabs from the ophthalmology and paediatric departments were excluded. Patient comorbidities, detailed wound descriptions, acknowledgement of and documentation of culture and sensitivity results, and antibiotic changes during treatment were collected. Indictors of infection including white cell counts (WCCs) and C-reactive protein (CRP) were recorded. l Results: The study included 134 patients. Diabetes mellitus (61.9%, n=83) was the most common underlying comorbidity. Postoperative wounds were the most common type of wounds swabbed (34.3%). The wound swab characteristics were not fully documented in 27 patients (20.1%). The CRP results were not recorded in 39.6% and WCCs were not taken in 10.4% of patients. Wound swab results were not acknowledged in the medical notes of 76% of cases. l Conclusion: Wound swabs that were not indicated, lack of documentation and untimely acknowledgement of results were evident. This suggests that a significant proportion of wound swabs may not have been justified and had no impact on wound management. Our study clearly underlines the need for a more comprehensive guideline. l Declaration of interest: There was no sponsorship of this study. The authors have no conflict of interest to declare. l
antibiotics; wound swabs; resources; documentation; guidelines; wound swab form
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care but not all types of wound. Here, we assess practice regarding wound swab use at Mater Dei Hospital, in order to identify any problems and provide recommendations for improvements in the current guidelines.
Materials and methods Wound swabs from adult inpatients received by the bacteriology laboratory between February and April 2013 were included. Exclusion criteria included wound swabs taken from outpatients, and those from the ophthalmology and paediatric departments. From the included patients swabs were randomly selected. Demographic data and patient comorbidities were collected from the patients’ notes. Length of stay in hospital, reason for admission and any associated infections were recorded. The documentation on the type of wound, site and its characteristics such as the presence of erythema and pus was used to determine whether a wound swab was indicated. Wound management and any input by the plastic surgeons, microbiology and infectious diseases teams were audited. Parameters of infection including fever, WCC and C-reactive protein (CRP) were all recorded. The patients’ medical records were checked for acknowledgement and documentation of culture and sensitivity results. Empirical antibiot-
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rocessing wound swabs is laborious and requires considerable financial resources. Each wound swab on average is estimated to cost €53.72. The bacteriology laboratory at Mater Dei hospital, Malta, receives an average of 7,000 wound swabs each year, thus amounting to approximately €376,000. Specific criteria help to determine the indications for taking a wound swab. These include local features such as the presence of erythema, pain, oedema, and pus, and systemic features, a raised temperature, white cell count (WCC) and inflammatory markers. Although there is no universal consensus regarding the exact indications for taking a wound swab, medical institutions often issue good-practice guidelines based on these criteria. This is usually heavily influenced by local bacterial epidemiology. Such guidelines should be stringently followed to help avoid the antibiotic treatment of uninfected wounds and the considerable financial costs associated with the laboratory processing of wound swabs that were not indicated. Guidelines exist at Mater Dei hospital for antibiotic management of lower-limb wounds, ulcers and the management of postoperative wound infections. These guidelines cover the types of wounds most commonly encountered in clinical
© 2014 MA Healthcare
M. Fenech, MD, MRCP UK, Higher Specialist Trainee; R. Abela, MD, Higher Specialist Trainee; S. Chetcuti Zammit, MD, MRCP UK, Higher Specialist Trainee; L. Mercieca, MD, MRCP UK, Higher Specialist Trainee; J. Gauci, MD, Basic Specialist Trainee; N. Edwards, MD, House Officer; E. Carachi, MD, MRCP UK, Higher Specialist Trainee; M. Mifsud, MD, MRCP UK, Basic Specialist Trainee; T. Piscopo, MD, FRCP (Lond), DTM&H (Lond), Consultant;
J O U R N A L O F WO U N D C A R E V O L 2 3 , N O 1 2 , D E C E M B E R 2 0 1 4
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practice otics after receiving the wound swab results as well as any organisms cultured were recorded.
Table 1. Underlying co-morbidities n=134 Diabetes mellitus
61.9% (n=83)
Ischaemic heart disease
35.8% (n=48)
Surgery in the previous two weeks
20.9% (n=28)
Peripheral vascular disease
32.8% (n=44)
Chronic kidney disease
17.2% (n=23)
Stroke
Statistics Statistical analysis was carried out using SPSS predictive analysis software (version 19). The data is presented as mean±standard deviation (sd) or as a percentage where appropriate.
7.5% (n=10)
Soft tissue infections
Results
12.7% (n=17)
Trauma
6.7% (n=9)
Chest infection
6.0% (n=8)
Table 2. Wound type n=134 Surgical wound
34.3% (n=46)
Diabetic ulcer
26.1% (n=35)
Ischaemic ulcer
16.4% (n=22)
Pressure ulcer
10.4% (n=14)
Others
12.7% (n=17)
Table 3. Wound site n=134 Lower limb
70.9% (n=95)
Abdominal wounds
11.2% (n=15)
Upper limb
1.5% (n=2)
Sacrum
6.7% (n=9)
Other
9.7% (n=13)
ics administered (the choice of antibiotics before antibiotic sensitivities are known, targeted towards the likely organisms present), any change of antibi-
The study included 134 randomly selected patients including 69 males (51.5%) and 65 females (48.5%). The mean age of the patient group was 65.0±18 (mean±sd) years and the mean length of hospital stay was 17.8±26.4 days. Diabetes mellitus was the most common underlying comorbidity (61.9%, n=83; Table 1) The most common wound types were surgical wounds (34.3%, n=46) and diabetic ulcers (26.1%, n=35; Table 2) The lower limbs were the most frequently affected site (70.9%; n=95; Table 3) Fever was documented in 15.7% (n=21) of patients. In 81 cases CRP (60.4%) and 120 cases WCC (89.6%; n=120) were taken within two days of swabbing. The number of consultations with the infectious disease and microbiology teams before swabbing (23.9%; n=32) and after result authorisation (the issue of the results for review by the team through an electronic system) (20.1%; n=27) was similar. Debridement was required in 18.7% of wounds (n=25), while 11.9% (n=16) required incision and drainage. Plastic surgery input was required in 4.5% (n=6) of cases and 17.2% (n=23) required amputation. A sample of pus was sent for culture in 11.9% of cases (n=16).
Fig 1. Characteristics of wound infections 100% 90% 80%
46.7%
69.6%
68.1%
66.7%
74.1%
45.9%
60.0%
61.5%
70% 60% 50%
8.9%
10.3%
40%
20% 10% 0%
43.0%
18.5%
Surrounding Surrounding cellulitis oedema
20.0%
20.0%
14.0%
13.3%
20.0%
ltd
11.9%
11.9%
19.3%
5.9%
45.2%
20.0%
25.2%
Clan base
Slough
Granulation tissue
Pus/ discharge
Necrotic tissue
Pain/ tenderness
■ Not documented ■ Documented as absent ■ Present
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30%
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practice Fig 2. Days taken to change antibiotics 12 10 Number of patients
There was failure of documentation of wound characteristics ranging from 45.9% to 74.1% of cases. (Fig 1). The presence or absence of granulation tissue, surrounding oedema and a clean wound base, were among the least documented characteristics. The culture results were acknowledged in the clinical records of patients in 23.9% of cases (n=32). Empirical antibiotics were given to 23.9% (n=32) of patients. Antibiotics were changed in 23.1% (n=31) of all patients. When antibiotics were changed, this was usually done within the first 2 days of result authorisation (Fig 2). Ciprofloxacin was the most common antibiotic started empirically for a wound infection (35.8% of patients, n=48). This was followed by clindamycin in 43 patients (32.1%; Fig 3). Clindamycin and ciprofloxacin were given together empirically in 21.6% (n=29) of patients. More than one antibiotic was started in 54.5% (n=73) of patients before wound swabbing. Three empirical antibiotics or more were started in 6.7% of these (n=9). The most common organisms cultured were Enterococcus sp. (17.9%, n=24), Escherichia sp. (17.1%, n=23) and Pseudomonas sp. (16.4%, n=22; Fig 4). One organism was identified in 35.8% of patients (n=48). Multiple organisms (two or three) were identified (n=43) in 32.1% of patients. The ratio of Meticillin-resistant Staphylococcus aureus (MRSA) (8.0%) to that of Meticillin-sensitive Staphylococcus aureus (MSSA) (8.5%) cultured from wounds was 1:1 (Fig 4). The use of ciprofloxacin, clindamycin and gentamicin was 35.8%, 32.1% and 10.4% respectively. Flucloxacillin was used in 7.5%, co-trimoxazole was used in 4.5% and doxycycline was used in 3.0% of patients. Antibiotics were changed on 26.1% (n=35) of occasions in which one or more organisms were cultured. In highly mixed cultures only 1 patient (0.04%) received a change in treatment.
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8 6
5
4
3 2
2 0
1
1 0
0
1
2
3
4
5
6
7
Number of days until change of antibiotics
for a wound swab was very rarely included in the management plan written by the patients’ caring firm (a consultant, a specialised registrar, a basic specialist trainee and a house officer). It was thus very hard to determine whether it was the caring firm or another health professional who felt the need to take a wound swab. This study identifies the need to increase awareness of this problem among medical professionals and the need to develop appropriate guidelines. The guidelines do not specify when wound swabs should be taken. This indicates a lack of an appropriate approach towards wound swabbing, which should start with a clear indication, clear documentation and a standard technique.
Discussion There was a high incidence of diabetes mellitus among the patients who had a wound swab taken. Diabetic patients have a higher incidence of cellulitis and complicated wound infections when compared to the general population.2 1 There was also a significant number of patients with underlying ischaemic heart disease and peripheral vascular disease. There was also a high mean age of the cohort studied (65 years). This suggests that patients with underlying comorbidities and the elderly are more prone to suffer from wounds and their complications. A lack of documentation of the type and characteristics of wounds was evident in both the nursing and doctors’ notes. Such poor wound documentation increases the difficulty of determining the indication for wound swabbing. The request J O U R N A L O F WO U N D C A R E V O L 2 3 , N O 1 2 , D E C E M B E R , 2 0 1 4
Fig 3. Empirical antibiotics targeted at wound infections. Ciprofloxacin Clindamycin Gentamicin Flucloxacillin -lactam/ -lactamase inhibitor combination Carbapenems Glycopeptides Metronidazole Co-trimoxazole Tigecycline Doxycycline 3rd generation cephalosporins 2nd generation cephalosporins Levofloxacin Polymixin Penicillin Fusidic acid Nitrofurantoin Amikacin
10.4% 7.5% 7.5% 6.7% 6.0% 5.2% 4.5% 3.7% 3.0% 2.2% 1.5% 1.5% 1.5% 0.7% 0.7% 0.7% 0.7%
35.8% 32.1%
s
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Highly mixed Enterococcus spp. Escherichia spp. Pseudomonas spp. No pathogenic bacteria MSSA MRSA Streptococcus spp. Morganella spp. Klebsiella spp. Serratia spp. Enterobacter spp. Proteus spp. Citrobacter spp. Candida spp. Bacteroides spp. Alcaligenes spp. Providencia spp.
18.7% 17.9% 17.1% 16.4% 13.4% 12.7% 11.9% 9.7% 8.2% 8.2% 5.2% 3.0% 3.0% 2.2% 0.7% 0.7% 0.7% 0.7%
There was a similar rate of consultation with the infectious diseases and microbiology team before swabbing when compared to that following result authorisation. CRP and WCC are recognised as important parameters in wound management.2,3 In this study CRP levels were not taken in 39.6% and no WCC taken in 10.4% of patients two days either side of swabbing the wound. Measurements of CRP and WCC are helpful indicators of whether a wound swab is required and for monitoring progress.4 The lack of these investigations makes it difficult to determine whether the wound swabs taken were actually indicated. Our local guidelines do not highlight the need to take a CRP and WCC except in systemic sepsis. To our knowledge this is the only study of its kind which assesses the note taking and acknowledgement of the swab results and sensitivities. Here, only 24% of wound swab results were acknowledged in patients’ notes. This approximately corresponds to the 23.1% of patients who had their antibiotics changed. This implies that acknowledgement of results led to an antibiotic change depending on sensitivities. The omission and overlooking of such information suggests that wound swab results were not used by the clinician in wound management. This could imply a waste of resources. The total cost per year would amount to approximately €376,000. Wound swabs were not acknowledged in 76% of cases. These would amount to €285,760 wasted resources as the tests were performed but the results not used. Interestingly, the ratio of MRSA (8.0%) to that of MSSA (8.5%) cultured from wounds is similar to the ratio of these organisms as isolated from blood cultures and other clinical samples in our hospital. In 640
the literature, only Portugal has a 1:1 ratio of MRSA to MMSA from blood cultures. The rest of the countries have a lower MRSA to MMSA ratio.5 According to the 2012 European antimicrobial surveillance report, Portugal and Romania had the highest incidence of MRSA (54%), with Malta ranking close behind at 47%.6 Highly mixed cultures were reported in 18.7% of cases, the most commonly reported result for all the wound swabs included in the audit. This implies incorrect wound swabbing technique7 or that bacteria were potentially colonising the wound rather than causing an infection. Colonisation itself can cause infection but, if the wound is not properly cleansed before swabbing, a wound swab can represent a colony of different bacteria rather than a specific type of bacteria-causing infection. This highlights the need to emphasise guidelines on wound swabbing technique. The presence of highly mixed cultures will inevitably lead to a lower pick-up rate of potentially pathogenic organisms. Hence this would delay starting the appropriate antibiotic treatment targeting these pathogens. The guidelines do not indicate when a wound swab should be taken but guide the physician in the antibiotic management of wound swabs by taking into consideration clinical features of sepsis. Also, only certain types of wounds are covered. These include lower limb ulcers and postoperative wounds. There are no dedicated guidelines for the management of diabetic ulcers, ischaemic ulcers and pressure ulcers. According to the guidelines, patients with nonsevere infections should be treated with doxycycline or flucloxacillin, and patients with severe infections should be given either clindamycin and ciprofloxacin or gentamicin. The presence of fever was necessary for the classification of a wound infection as severe. Due to lack of fever at the time of swabbing, 84.3% of patients had wound infections that were classified as not severe. Bearing in mind that the majority of wound swabs were taken from lower-limb ulcers and postoperative wounds, this study shows a lack of adherence to current guidelines on lower-limb wounds, where wounds characterised with a nonsevere infection were treated with the wrong antibiotics. Ciprofloxacin and clindamycin were used in 35.8% and 32.1% of cases respectively. They should have been used at most in the 15.7% of cases where they were classed as severely infected. There was overuse of clindamycin and ciprofloxacin and underuse of flucloxacillin, co-trimoxazole and doxycycline. Clindamycin and ciprofloxacin are higher risk antibiotics that predispose to Clostridium difficile infection.8
Wound swab form Here, we propose a wound swab form to help keep better track of a wound and its management (Fig 5)
© 2014 MA Healthcare
Fig 4. Organisms cultured from wound swabs
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practice
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practice Fig 5. Wound swab management form Name
Surname
ID number
Age (years)
Gender (M/F)
Wound site
Wound size (mm)
Date of wound
Wound type • Surgical wound • Trauma • Pressure ulcer • Diabetic ulcer • Ischaemic ulcer • Burn • Others
Wound history
DATE Temperature Wound characteristics Surrounding cellulitis Surrounding oedema Slough Granulation tissue Pus / discharge Necrotic tissue Pain / tenderness Smelly wound Erythema Clean base Investigations White cell count ESR CRP Choice of antibiotics Empirical antibiotics for wound infection
Antibiotics for other conditions
Date started
Date started
Date of sampling
Antibiotics according to C&S* result
Date of result authorisation
Date started
Debridement
Y/N
Plastic surgery input
Y/N
Incision and drainage
Y/N
Infectious Diseases input
Y/N
Amputation
Y/N
Microbiology input
Y/N
* C and S: Culture and Sensitivity
s
© 2014 MA Healthcare
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Management
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practice This can be used both by doctors and nurses, it is easy to fill in and it will help improve documentation. Guidelines for antibiotic management of specific wound types such as diabetic ulcers and pressure ulcers should be developed. We also aim to raise awareness about the importance of documentation as this will enable better use of resources and better wound care. Health professionals across all specialities and at all levels will be made aware of the existence of this form and the ease of its use as part of the hospital resources. They will also be made aware of the results of this study including the extreme waste of resources implied by the lack of documentation and the inappropriate use of antibiotics if wounds are swabbed incorrectly. Following the implementation of this wound swab form, reauditing can then be carried out. The form itself will enable us to develop a scoring system that will guide health professionals further as to when a wound swab should be taken.
Limitations Limitations of our study include the fact that a significant number of patients (74%) had a coexist-
References 1. Falanga,V. Wound healing and its impairment in the diabetic foot. Lancet 2005; 366: 9498,1736–1743. 2. Dzieciuchowicz, Ł.1., Kruszyna, Ł., Krasinski, Z., Espinosa, G. Monitoring of systemic inflammatory response in diabetic patients with deep foot infection treated with negative pressure wound therapy. Foot Ankle Int 2012; 33: 10, 832–837.
3. Kahn, M.H., Smith, P.N., Rao, N., Donaldson, W.F. Serum C-reative protein levels correlate with clinical response in patients treated with antibiotics for wound infections after spinal surgery. Spine J 2006; 6: 3, 311–315. 4. Fujii, T., Tabe,Y.,Yajima, R. et al. Relationship between C-reactive protein levels and wound infections in elective colorectal surgery: C-reactive protein as a predictor for incisional SSI.
ing infective process or were in hospital following surgery. Therefore antibiotics might have been administered for reasons other than an infected wound. Lack of documentation of both wound description and acknowledgement of results, is another limitation of our study in itself, as we could not infer whether wound swabbing was indicated or not.
Conclusions Failure of documentation of wound characteristics and lack of acknowledgement of culture results were evident in this study. Overuse of clindamycin and ciprofloxacin was also apparent. Wound swabs that are not indicated, lack of documentation and untimely acknowledgement of culture results can lead to considerable waste of financial and laboratory resources. Our study clearly underlines the need for a more comprehensive guideline on wound swab taking and management of wounds. This should aid both doctors and nurses in the proper management of infected wounds. n
Hepatogastroenterology 2011; 58: 752–755. 5. MRSA Survivors network. www.mrsasurvivors.org/mrsa/ wp-content/uploads/2010/12/ EARSS-map-2006-2008.pdf; 2008. (assessed November 2014) 6. European Centre for Disease Prevention and Control. Annual Report of the European Antimicrobial Resistance Surveillance Network. Antimicrobial resistance www. ecdc.europa.eu/en/activities/
surveillance/EARS-Net/Pages/ index.aspx surveillance in Europe 2012 (assessed November 2014) 7 Starr, S,. MacLeod, T. Wound swabbing technique. Nurs Times 2003; 99: 5, 57–59. 8 Brown, K.A.1., Khanafer, N., Daneman, N., Fisman, D.N. Meta-analysis of antibiotics and the risk of community-associated Clostridium difficile infection. Antimicrob Agents Chemother. 2013; 57: 5, 2326–2332.
Geroult, S., Phillips, R.O, Demangel, C. Adhesion of the ulcerative pathogen Mycobacterium ulcerans to DACC-coated dressings. J Wound Care 2014; 23: 8, 417–424. In this original research article, the statement in the result section of the abstract: ‘Mycobacterium ulcerans bacteria bound DACC-coated dressings were better than untreated controls.’ is
642
incorrect. It should be corrected to: Mycobacterium ulcerans bacteria bound to DACC-coated dressings better than untreated controls. In the discussion on page 422 the statement: ‘Given pivotal role wwplayed by mycolactone in the pathogenesis of Buruli ulcers, dressings that efficiently capture mycolactone may help to improve its elimination from the wounds and shorten the current eight-week daily
treatment with streptomyci nand rifampicin’ is incorrect. It should be corrected to: Given pivotal role played by mycolactone in the pathogenesis of Buruli ulcers, dressings that efficiently capture mycolactone may help to improve its elimination from the wounds and shorten the current eightweek daily treatment with streptomycin and rifampicin’ The Journal of Wound Care would like to apologise for these errors.
© 2014 MA Healthcare
Erratum in:
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erratum
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Wound swab use and misuse at a regional general hospital Objective: Guidelines for swab use at our centre cover lower-limb wounds, ulcers and postoperative wound infections but not all types of wound. The objective of this study was to assess current practices in wound management at Mater Dei Hospital and to identify areas for improvement. l Method: Wound swabs received at the microbiology department between February and April 2013 from adult inpatients departments were included.Wound swabs from the ophthalmology and paediatric departments were excluded. Patient comorbidities, detailed wound descriptions, acknowledgement of and documentation of culture and sensitivity results, and antibiotic changes during treatment were collected. Indictors of infection including white cell counts (WCCs) and C-reactive protein (CRP) were recorded. l Results: The study included 134 patients. Diabetes mellitus (61.9%, n=83) was the most common underlying comorbidity. Postoperative wounds were the most common type of wounds swabbed (34.3%). The wound swab characteristics were not fully documented in 27 patients (20.1%). The CRP results were not recorded in 39.6% and WCCs were not taken in 10.4% of patients. Wound swab results were not acknowledged in the medical notes of 76% of cases. l Conclusion: Wound swabs that were not indicated, lack of documentation and untimely acknowledgement of results were evident. This suggests that a significant proportion of wound swabs may not have been justified and had no impact on wound management. Our study clearly underlines the need for a more comprehensive guideline. l Declaration of interest: There was no sponsorship of this study. The authors have no conflict of interest to declare. l
antibiotics; wound swabs; resources; documentation; guidelines; wound swab form
634
care but not all types of wound. Here, we assess practice regarding wound swab use at Mater Dei Hospital, in order to identify any problems and provide recommendations for improvements in the current guidelines.
Materials and methods Wound swabs from adult inpatients received by the bacteriology laboratory between February and April 2013 were included. Exclusion criteria included wound swabs taken from outpatients, and those from the ophthalmology and paediatric departments. From the included patients swabs were randomly selected. Demographic data and patient comorbidities were collected from the patients’ notes. Length of stay in hospital, reason for admission and any associated infections were recorded. The documentation on the type of wound, site and its characteristics such as the presence of erythema and pus was used to determine whether a wound swab was indicated. Wound management and any input by the plastic surgeons, microbiology and infectious diseases teams were audited. Parameters of infection including fever, WCC and C-reactive protein (CRP) were all recorded. The patients’ medical records were checked for acknowledgement and documentation of culture and sensitivity results. Empirical antibiot-
ltd
Email: stf_che@yahoo. com
P
rocessing wound swabs is laborious and requires considerable financial resources. Each wound swab on average is estimated to cost €53.72. The bacteriology laboratory at Mater Dei hospital, Malta, receives an average of 7,000 wound swabs each year, thus amounting to approximately €376,000. Specific criteria help to determine the indications for taking a wound swab. These include local features such as the presence of erythema, pain, oedema, and pus, and systemic features, a raised temperature, white cell count (WCC) and inflammatory markers. Although there is no universal consensus regarding the exact indications for taking a wound swab, medical institutions often issue good-practice guidelines based on these criteria. This is usually heavily influenced by local bacterial epidemiology. Such guidelines should be stringently followed to help avoid the antibiotic treatment of uninfected wounds and the considerable financial costs associated with the laboratory processing of wound swabs that were not indicated. Guidelines exist at Mater Dei hospital for antibiotic management of lower-limb wounds, ulcers and the management of postoperative wound infections. These guidelines cover the types of wounds most commonly encountered in clinical
© 2014 MA Healthcare
M. Fenech, MD, MRCP UK, Higher Specialist Trainee; R. Abela, MD, Higher Specialist Trainee; S. Chetcuti Zammit, MD, MRCP UK, Higher Specialist Trainee; L. Mercieca, MD, MRCP UK, Higher Specialist Trainee; J. Gauci, MD, Basic Specialist Trainee; N. Edwards, MD, House Officer; E. Carachi, MD, MRCP UK, Higher Specialist Trainee; M. Mifsud, MD, MRCP UK, Basic Specialist Trainee; T. Piscopo, MD, FRCP (Lond), DTM&H (Lond), Consultant;
J O U R N A L O F WO U N D C A R E V O L 2 3 , N O 1 2 , D E C E M B E R 2 0 1 4
Journal of Wound Care. Downloaded from magonlinelibrary.com by 155.198.030.043 on August 9, 2015. For personal use only. No other uses without permission. . All rights reserved.
practice otics after receiving the wound swab results as well as any organisms cultured were recorded.
Table 1. Underlying co-morbidities n=134 Diabetes mellitus
61.9% (n=83)
Ischaemic heart disease
35.8% (n=48)
Surgery in the previous two weeks
20.9% (n=28)
Peripheral vascular disease
32.8% (n=44)
Chronic kidney disease
17.2% (n=23)
Stroke
Statistics Statistical analysis was carried out using SPSS predictive analysis software (version 19). The data is presented as mean±standard deviation (sd) or as a percentage where appropriate.
7.5% (n=10)
Soft tissue infections
Results
12.7% (n=17)
Trauma
6.7% (n=9)
Chest infection
6.0% (n=8)
Table 2. Wound type n=134 Surgical wound
34.3% (n=46)
Diabetic ulcer
26.1% (n=35)
Ischaemic ulcer
16.4% (n=22)
Pressure ulcer
10.4% (n=14)
Others
12.7% (n=17)
Table 3. Wound site n=134 Lower limb
70.9% (n=95)
Abdominal wounds
11.2% (n=15)
Upper limb
1.5% (n=2)
Sacrum
6.7% (n=9)
Other
9.7% (n=13)
ics administered (the choice of antibiotics before antibiotic sensitivities are known, targeted towards the likely organisms present), any change of antibi-
The study included 134 randomly selected patients including 69 males (51.5%) and 65 females (48.5%). The mean age of the patient group was 65.0±18 (mean±sd) years and the mean length of hospital stay was 17.8±26.4 days. Diabetes mellitus was the most common underlying comorbidity (61.9%, n=83; Table 1) The most common wound types were surgical wounds (34.3%, n=46) and diabetic ulcers (26.1%, n=35; Table 2) The lower limbs were the most frequently affected site (70.9%; n=95; Table 3) Fever was documented in 15.7% (n=21) of patients. In 81 cases CRP (60.4%) and 120 cases WCC (89.6%; n=120) were taken within two days of swabbing. The number of consultations with the infectious disease and microbiology teams before swabbing (23.9%; n=32) and after result authorisation (the issue of the results for review by the team through an electronic system) (20.1%; n=27) was similar. Debridement was required in 18.7% of wounds (n=25), while 11.9% (n=16) required incision and drainage. Plastic surgery input was required in 4.5% (n=6) of cases and 17.2% (n=23) required amputation. A sample of pus was sent for culture in 11.9% of cases (n=16).
Fig 1. Characteristics of wound infections 100% 90% 80%
46.7%
69.6%
68.1%
66.7%
74.1%
45.9%
60.0%
61.5%
70% 60% 50%
8.9%
10.3%
40%
20% 10% 0%
43.0%
18.5%
Surrounding Surrounding cellulitis oedema
20.0%
20.0%
14.0%
13.3%
20.0%
ltd
11.9%
11.9%
19.3%
5.9%
45.2%
20.0%
25.2%
Clan base
Slough
Granulation tissue
Pus/ discharge
Necrotic tissue
Pain/ tenderness
■ Not documented ■ Documented as absent ■ Present
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practice Fig 2. Days taken to change antibiotics 12 10 Number of patients
There was failure of documentation of wound characteristics ranging from 45.9% to 74.1% of cases. (Fig 1). The presence or absence of granulation tissue, surrounding oedema and a clean wound base, were among the least documented characteristics. The culture results were acknowledged in the clinical records of patients in 23.9% of cases (n=32). Empirical antibiotics were given to 23.9% (n=32) of patients. Antibiotics were changed in 23.1% (n=31) of all patients. When antibiotics were changed, this was usually done within the first 2 days of result authorisation (Fig 2). Ciprofloxacin was the most common antibiotic started empirically for a wound infection (35.8% of patients, n=48). This was followed by clindamycin in 43 patients (32.1%; Fig 3). Clindamycin and ciprofloxacin were given together empirically in 21.6% (n=29) of patients. More than one antibiotic was started in 54.5% (n=73) of patients before wound swabbing. Three empirical antibiotics or more were started in 6.7% of these (n=9). The most common organisms cultured were Enterococcus sp. (17.9%, n=24), Escherichia sp. (17.1%, n=23) and Pseudomonas sp. (16.4%, n=22; Fig 4). One organism was identified in 35.8% of patients (n=48). Multiple organisms (two or three) were identified (n=43) in 32.1% of patients. The ratio of Meticillin-resistant Staphylococcus aureus (MRSA) (8.0%) to that of Meticillin-sensitive Staphylococcus aureus (MSSA) (8.5%) cultured from wounds was 1:1 (Fig 4). The use of ciprofloxacin, clindamycin and gentamicin was 35.8%, 32.1% and 10.4% respectively. Flucloxacillin was used in 7.5%, co-trimoxazole was used in 4.5% and doxycycline was used in 3.0% of patients. Antibiotics were changed on 26.1% (n=35) of occasions in which one or more organisms were cultured. In highly mixed cultures only 1 patient (0.04%) received a change in treatment.
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for a wound swab was very rarely included in the management plan written by the patients’ caring firm (a consultant, a specialised registrar, a basic specialist trainee and a house officer). It was thus very hard to determine whether it was the caring firm or another health professional who felt the need to take a wound swab. This study identifies the need to increase awareness of this problem among medical professionals and the need to develop appropriate guidelines. The guidelines do not specify when wound swabs should be taken. This indicates a lack of an appropriate approach towards wound swabbing, which should start with a clear indication, clear documentation and a standard technique.
Discussion There was a high incidence of diabetes mellitus among the patients who had a wound swab taken. Diabetic patients have a higher incidence of cellulitis and complicated wound infections when compared to the general population.2 1 There was also a significant number of patients with underlying ischaemic heart disease and peripheral vascular disease. There was also a high mean age of the cohort studied (65 years). This suggests that patients with underlying comorbidities and the elderly are more prone to suffer from wounds and their complications. A lack of documentation of the type and characteristics of wounds was evident in both the nursing and doctors’ notes. Such poor wound documentation increases the difficulty of determining the indication for wound swabbing. The request J O U R N A L O F WO U N D C A R E V O L 2 3 , N O 1 2 , D E C E M B E R , 2 0 1 4
Fig 3. Empirical antibiotics targeted at wound infections. Ciprofloxacin Clindamycin Gentamicin Flucloxacillin -lactam/ -lactamase inhibitor combination Carbapenems Glycopeptides Metronidazole Co-trimoxazole Tigecycline Doxycycline 3rd generation cephalosporins 2nd generation cephalosporins Levofloxacin Polymixin Penicillin Fusidic acid Nitrofurantoin Amikacin
10.4% 7.5% 7.5% 6.7% 6.0% 5.2% 4.5% 3.7% 3.0% 2.2% 1.5% 1.5% 1.5% 0.7% 0.7% 0.7% 0.7%
35.8% 32.1%
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Highly mixed Enterococcus spp. Escherichia spp. Pseudomonas spp. No pathogenic bacteria MSSA MRSA Streptococcus spp. Morganella spp. Klebsiella spp. Serratia spp. Enterobacter spp. Proteus spp. Citrobacter spp. Candida spp. Bacteroides spp. Alcaligenes spp. Providencia spp.
18.7% 17.9% 17.1% 16.4% 13.4% 12.7% 11.9% 9.7% 8.2% 8.2% 5.2% 3.0% 3.0% 2.2% 0.7% 0.7% 0.7% 0.7%
There was a similar rate of consultation with the infectious diseases and microbiology team before swabbing when compared to that following result authorisation. CRP and WCC are recognised as important parameters in wound management.2,3 In this study CRP levels were not taken in 39.6% and no WCC taken in 10.4% of patients two days either side of swabbing the wound. Measurements of CRP and WCC are helpful indicators of whether a wound swab is required and for monitoring progress.4 The lack of these investigations makes it difficult to determine whether the wound swabs taken were actually indicated. Our local guidelines do not highlight the need to take a CRP and WCC except in systemic sepsis. To our knowledge this is the only study of its kind which assesses the note taking and acknowledgement of the swab results and sensitivities. Here, only 24% of wound swab results were acknowledged in patients’ notes. This approximately corresponds to the 23.1% of patients who had their antibiotics changed. This implies that acknowledgement of results led to an antibiotic change depending on sensitivities. The omission and overlooking of such information suggests that wound swab results were not used by the clinician in wound management. This could imply a waste of resources. The total cost per year would amount to approximately €376,000. Wound swabs were not acknowledged in 76% of cases. These would amount to €285,760 wasted resources as the tests were performed but the results not used. Interestingly, the ratio of MRSA (8.0%) to that of MSSA (8.5%) cultured from wounds is similar to the ratio of these organisms as isolated from blood cultures and other clinical samples in our hospital. In 640
the literature, only Portugal has a 1:1 ratio of MRSA to MMSA from blood cultures. The rest of the countries have a lower MRSA to MMSA ratio.5 According to the 2012 European antimicrobial surveillance report, Portugal and Romania had the highest incidence of MRSA (54%), with Malta ranking close behind at 47%.6 Highly mixed cultures were reported in 18.7% of cases, the most commonly reported result for all the wound swabs included in the audit. This implies incorrect wound swabbing technique7 or that bacteria were potentially colonising the wound rather than causing an infection. Colonisation itself can cause infection but, if the wound is not properly cleansed before swabbing, a wound swab can represent a colony of different bacteria rather than a specific type of bacteria-causing infection. This highlights the need to emphasise guidelines on wound swabbing technique. The presence of highly mixed cultures will inevitably lead to a lower pick-up rate of potentially pathogenic organisms. Hence this would delay starting the appropriate antibiotic treatment targeting these pathogens. The guidelines do not indicate when a wound swab should be taken but guide the physician in the antibiotic management of wound swabs by taking into consideration clinical features of sepsis. Also, only certain types of wounds are covered. These include lower limb ulcers and postoperative wounds. There are no dedicated guidelines for the management of diabetic ulcers, ischaemic ulcers and pressure ulcers. According to the guidelines, patients with nonsevere infections should be treated with doxycycline or flucloxacillin, and patients with severe infections should be given either clindamycin and ciprofloxacin or gentamicin. The presence of fever was necessary for the classification of a wound infection as severe. Due to lack of fever at the time of swabbing, 84.3% of patients had wound infections that were classified as not severe. Bearing in mind that the majority of wound swabs were taken from lower-limb ulcers and postoperative wounds, this study shows a lack of adherence to current guidelines on lower-limb wounds, where wounds characterised with a nonsevere infection were treated with the wrong antibiotics. Ciprofloxacin and clindamycin were used in 35.8% and 32.1% of cases respectively. They should have been used at most in the 15.7% of cases where they were classed as severely infected. There was overuse of clindamycin and ciprofloxacin and underuse of flucloxacillin, co-trimoxazole and doxycycline. Clindamycin and ciprofloxacin are higher risk antibiotics that predispose to Clostridium difficile infection.8
Wound swab form Here, we propose a wound swab form to help keep better track of a wound and its management (Fig 5)
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Fig 4. Organisms cultured from wound swabs
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practice Fig 5. Wound swab management form Name
Surname
ID number
Age (years)
Gender (M/F)
Wound site
Wound size (mm)
Date of wound
Wound type • Surgical wound • Trauma • Pressure ulcer • Diabetic ulcer • Ischaemic ulcer • Burn • Others
Wound history
DATE Temperature Wound characteristics Surrounding cellulitis Surrounding oedema Slough Granulation tissue Pus / discharge Necrotic tissue Pain / tenderness Smelly wound Erythema Clean base Investigations White cell count ESR CRP Choice of antibiotics Empirical antibiotics for wound infection
Antibiotics for other conditions
Date started
Date started
Date of sampling
Antibiotics according to C&S* result
Date of result authorisation
Date started
Debridement
Y/N
Plastic surgery input
Y/N
Incision and drainage
Y/N
Infectious Diseases input
Y/N
Amputation
Y/N
Microbiology input
Y/N
* C and S: Culture and Sensitivity
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practice This can be used both by doctors and nurses, it is easy to fill in and it will help improve documentation. Guidelines for antibiotic management of specific wound types such as diabetic ulcers and pressure ulcers should be developed. We also aim to raise awareness about the importance of documentation as this will enable better use of resources and better wound care. Health professionals across all specialities and at all levels will be made aware of the existence of this form and the ease of its use as part of the hospital resources. They will also be made aware of the results of this study including the extreme waste of resources implied by the lack of documentation and the inappropriate use of antibiotics if wounds are swabbed incorrectly. Following the implementation of this wound swab form, reauditing can then be carried out. The form itself will enable us to develop a scoring system that will guide health professionals further as to when a wound swab should be taken.
Limitations Limitations of our study include the fact that a significant number of patients (74%) had a coexist-
References 1. Falanga,V. Wound healing and its impairment in the diabetic foot. Lancet 2005; 366: 9498,1736–1743. 2. Dzieciuchowicz, Ł.1., Kruszyna, Ł., Krasinski, Z., Espinosa, G. Monitoring of systemic inflammatory response in diabetic patients with deep foot infection treated with negative pressure wound therapy. Foot Ankle Int 2012; 33: 10, 832–837.
3. Kahn, M.H., Smith, P.N., Rao, N., Donaldson, W.F. Serum C-reative protein levels correlate with clinical response in patients treated with antibiotics for wound infections after spinal surgery. Spine J 2006; 6: 3, 311–315. 4. Fujii, T., Tabe,Y.,Yajima, R. et al. Relationship between C-reactive protein levels and wound infections in elective colorectal surgery: C-reactive protein as a predictor for incisional SSI.
ing infective process or were in hospital following surgery. Therefore antibiotics might have been administered for reasons other than an infected wound. Lack of documentation of both wound description and acknowledgement of results, is another limitation of our study in itself, as we could not infer whether wound swabbing was indicated or not.
Conclusions Failure of documentation of wound characteristics and lack of acknowledgement of culture results were evident in this study. Overuse of clindamycin and ciprofloxacin was also apparent. Wound swabs that are not indicated, lack of documentation and untimely acknowledgement of culture results can lead to considerable waste of financial and laboratory resources. Our study clearly underlines the need for a more comprehensive guideline on wound swab taking and management of wounds. This should aid both doctors and nurses in the proper management of infected wounds. n
Hepatogastroenterology 2011; 58: 752–755. 5. MRSA Survivors network. www.mrsasurvivors.org/mrsa/ wp-content/uploads/2010/12/ EARSS-map-2006-2008.pdf; 2008. (assessed November 2014) 6. European Centre for Disease Prevention and Control. Annual Report of the European Antimicrobial Resistance Surveillance Network. Antimicrobial resistance www. ecdc.europa.eu/en/activities/
surveillance/EARS-Net/Pages/ index.aspx surveillance in Europe 2012 (assessed November 2014) 7 Starr, S,. MacLeod, T. Wound swabbing technique. Nurs Times 2003; 99: 5, 57–59. 8 Brown, K.A.1., Khanafer, N., Daneman, N., Fisman, D.N. Meta-analysis of antibiotics and the risk of community-associated Clostridium difficile infection. Antimicrob Agents Chemother. 2013; 57: 5, 2326–2332.
Geroult, S., Phillips, R.O, Demangel, C. Adhesion of the ulcerative pathogen Mycobacterium ulcerans to DACC-coated dressings. J Wound Care 2014; 23: 8, 417–424. In this original research article, the statement in the result section of the abstract: ‘Mycobacterium ulcerans bacteria bound DACC-coated dressings were better than untreated controls.’ is
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incorrect. It should be corrected to: Mycobacterium ulcerans bacteria bound to DACC-coated dressings better than untreated controls. In the discussion on page 422 the statement: ‘Given pivotal role wwplayed by mycolactone in the pathogenesis of Buruli ulcers, dressings that efficiently capture mycolactone may help to improve its elimination from the wounds and shorten the current eight-week daily
treatment with streptomyci nand rifampicin’ is incorrect. It should be corrected to: Given pivotal role played by mycolactone in the pathogenesis of Buruli ulcers, dressings that efficiently capture mycolactone may help to improve its elimination from the wounds and shorten the current eightweek daily treatment with streptomycin and rifampicin’ The Journal of Wound Care would like to apologise for these errors.
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